Antibiotics for the empirical treatment of acute infectious diarrhea in children

REVIEW ARTICLES

Antibiotics for the empirical treatment of acute infectious diarrhea in children

Daniel R. Diniz-Santos; Luciana R. Silva; Nanci Silva

Division of Pediatric Gastroenterology and Hepatology, Professor Hosannah Oliveira Pediatric Center, Federal University of Bahia; Salvador, BA, Brazil

^{Address for correspondence}

ABSTRACT

While the routine use of antibiotics for infectious diarrhea in children must be avoided, because it brings little benefit in most cases and is associated with the risk of increasing antimicrobial resistance, selected cases may require antimicrobial therapy, and the choice of the antimicrobial agent often has to be made empirically. Physicians prescribing antimicrobials in such a setting have not only to be aware of the most likely pathogens, but also of their characteristic antimicrobial susceptibility pattern and the safety profile of the various drugs. We reviewed the literature on the use of ampicillin, beta-lactamase inhibitors, trimethoprim-sulfamethoxazole, chloramphenicol, tetracyclines, nalidixic acid, fluoroquinolones, third-generation cephalosporins, macrolides, metronidazole and malabsorbed agents in the setting of acute infectious diarrhea, and we evaluated the available information, seeking to apply it to empirical use, highlighting clinically-useful pharmacological information and patients' and pathogens' characteristics that must be taken into account for decisions about antimicrobial therapy.

Key Words: Diarrhea, antibiotics, children, treatment.

Acute diarrhea remains one of the most important health issues worldwide, with high morbidity and mortality rates, accounting for more than two million deaths annually [1,2]. Acute diarrhea is the commonest infectious disease in developing countries, mostly affecting children younger than five years old. Whereas most cases of acute diarrhea are caused by virus, such as rotavirus and enteric adenovirus, and tend to present in a mild and self-limiting fashion, with the optimal treatment consisting solely of oral rehydration and nutritional support, practitioners in ambulatories or emergency rooms, especially in developing countries, are frequently faced with life-threatening presentations, characterized by signs of severe dehydration, toxemia, marked leucocytosis with high percentages of immature forms, high-grade fever, severe welfare depression, tenesmus, gross fecal blood loss and dissemination of infection. Supportive anti-dehydration therapy, associated with adequate nutritional support, is the cornerstone of therapy, regardless of the etiology and the severity of the process, and its prompt and early adoption is associated with a favorable outcome. Moreover, dehydration can simulate toxemia and mislead the clinical assessment of severity. As a consequence, volumetric expansion, electrolyte corrections and nutritional support should always be performed before any other therapeutic measure.

A few cases, however, may require antimicrobial therapy, because of the severity of the clinical picture or a patient's increased potential to develop complications, such as dissemination of the disease, sepsis or disseminated intravascular coagulation. Among those patients more prone to an unfavorable evolution are those receiving chemotherapy, HIV-positive, cirrhotics, diabetics, neonates, very young infants, the elderly, patients who have undergone organ transplantation or who have a lymphoproliferative disease, patients with sickle cell disease, or those with articular or cardiac valve prostheses. Additionally, the use of antibiotics is mandatory in severe cases of cholera, shigellosis and typhoid fever. Antimicrobial treatment tends to quicken the clinical resolution of diarrhea, prevent the progression of disease and reduce the severity of associated symptoms, such as fever, abdominal pain and vomiting. Furthermore, antimicrobial therapy decreases secondary cases, by halting person-to-person spread of most pathogens, which warrants special consideration for the use of antibiotics in the treatment of child-care workers, health professionals and workers in the catering industry or services. Prompt adoption of empirical antimicrobial therapy is also useful in the setting of febrile acute bloody diarrhea in young children and is currently recommended by the World Health Organization [3].

On the other hand, there are several arguments against the empirical use of antibiotics for acute infectious diarrhea. The most compelling of them is the fact that acute infectious diarrhea is typically a self-limiting disease, regardless of its etiology, with most cases resolving in less than three days [4]. Moreover, one must consider the low incidence of treatable pathogens among the causative agents of acute diarrhea (which are viruses in most cases), the possible occurrence of side effects, the potential development of resistant strains, the cost of treatment, and a possible noxious effects on the disease itself, as seen with enterohemorrhagic E. coli (EHEC) and non-typhoidal Salmonella. Additionally, virtually all oral antimicrobials are able to cause, or worsen, diarrhea because of their effect on gut microflora. Oral antimicrobials may also have their efficacy reduced by impaired intestinal absorption and enhanced intestinal motility.

The most severe drawback of widespread use of antimicrobials for the treatment of infectious diarrhea is the consequently rising rates of antimicrobial resistance, fostered by the unselected use of these drugs in patients with a mild presentation, with low risk for complications or who would recover well without antibiotics. This finding demonstrates the important role of doctors when they prescribe these drugs, especially to outpatients. Every case should be evaluated individually, considering the patient's age, nutritional status, risk for complications, characteristics of diarrhea with possible etiological agents, and the risks and benefits intrinsic to antimicrobial therapy. Laboratory information is particularly useful to help distinguish invasive enteropathogens (which may require antimicrobial therapy) from non-invasive agents, such as viruses (rotavirus, adenovirus, calicivirus, and astrovirus) and parasites (Giardia lamblia, Entamoeba histolytica and Criptosporium sp.).

Given the self-limiting nature of the disease, most patients with acute diarrhea do not require laboratorial evaluation and can be safely managed as outpatients. Severely ill patients may need hospitalization and further investigation, including complete blood counts, electrolyte dosing and stool culture. Rotavirus-associated diarrhea should always be excluded in such cases, given its propensity to cause severe and dehydrating pictures [5,6]. Blood culture may also be indicated in a few cases, depending on the severity and risk of hematogenic dissemination. Because of the low yield and extreme dependence on laboratory methods, the results of stool cultures should be carefully interpreted along with clinical findings. A negative culture by no means excludes the possibility of bacterial etiology in a patient with clinical signs of bacterial diarrhea. Additionally, a mixed infection may occur as well.

While stool cultures and antimicrobial testing of the isolates are the best way to select the most adequate antimicrobial regimen, the results are only available after 72 hours or more. In some instances, it is possible to wait for the result; often cases improve substantially during this interval and the use of antibiotics is no longer required when the results become available, even if enteropathogenic bacteria are identified. In severe cases, however, it is advisable to start antimicrobials empirically as soon as stools are collected for culture.

Since the use of antibiotics is associated with higher response rates if it is adopted early in the course of the disease, one is often not able to wait for the results of the stool culture before initiating antimicrobial therapy. Therefore, the decision to start antimicrobial therapy for acute diarrhea must be made solely on clinical grounds, and the choice of the antimicrobial agent has to be made empirically; it should consist of the narrowest antimicrobial spectrum possible that covers the most likely pathogens in each case. As soon as the results of the stool culture become available, the therapy may be altered according to the antimicrobial susceptibility pattern, favoring the use of narrower-spectrum, cheaper and/or safer drugs, if antimicrobial therapy remains necessary.

In order to decrease costs, as well as to reduce the possibility of increasing antimicrobial resistance among circulating strains, clinicians should choose the narrowest antibiotic regimen that adequately covers the predicted organisms for each case. Therefore, up-to-date knowledge of locally circulating strains and their antimicrobial susceptibility patterns is crucial. Clinicians must be wary of adopting antimicrobial susceptibility patterns reported by published studies from other countries, no matter how extensive and well designed they are, because the frequency of pathogens and their susceptibility patterns are highly variable from one part of the world to another. Certain clinical features may suggest specific etiological agents or help narrow the list of possible agents implicated, such as intense tenesmus with uncountable dejections, suggesting Shigella, right lower quadrant pain, suggesting Yersinia, or painless voluminous watery diarrhea without abdominal pain or fever, suggesting Vibrio cholerae. Severe bloody diarrhea in afebrile patients strongly suggests an EHEC-associated picture, especially if there is clustering of cases or a report of consumption of undercooked meat; the use of antibiotics should be avoided in such cases, because it increases toxin production and increases the risk of hemolytic-uremic syndrome [7,8]. In the case of patients who report the use of antibiotics during the weeks preceding an episode of diarrhea, one should examine the possibility of pseudomembranous colitis, caused by Clostridium difficile.

Despite the intrinsic limitations of stool cultures, laboratory investigation may also be helpful in judging the need for antibiotics for diarrheal patients. The detection of blood in the stools is a reliable indicator of invasive diarrhea, favoring the use of antibiotics if it is associated with other clinical or laboratorial hallmarks of invasive diarrhea. A simple enzyme-linked immunoabsorbent assay (ELISA) may identify rotavirus-associated cases of diarrhea and preclude the use of antibiotics. Also, the development of effective polymerase chain reaction-based techniques for stool analysis is expected to allow reliable early etiological diagnosis, guiding antimicrobial therapy, even in the absence of antimicrobial susceptibility testing, thus favoring the rational use of drugs. However, most clinical laboratories remain unable to identify enteropathogens, as the most sensitive methods remain restricted to a few research laboratories. Additionally, clinical laboratories are also unable to identify viral diarrheal pathogens other than rotavirus, and they normally cannot perform bacterial serotyping.

Ampicillin and Trimethoprim-Sulfamethoxazole

Ampicillin and trimethoprim-sulfamethoxazole (TMP-SMX) once were the drugs of choice for the empirical treatment of outpatients with acute infectious diarrhea, because of their efficacy, safety and affordability. With the passing of years, outbreaks of infectious diarrhea caused by Shigella or Salmonella strains resistant to one or both of them have been reported from all continents [9-18]. Even though these drugs may still be useful against some bacteria infecting outpatients or inpatients in various parts of the world, and though they have the obvious advantages of oral administration, the resistance of many pathogens has reached such high rates that their widespread empirical use can no longer be recommended [19-24], except when supported by detailed local knowledge of the sensibility pattern of circulating strains.

The association of ampicillin with the beta-lactamase inhibitor sulbactam provides enhanced antimicrobial activity, but increasing antimicrobial resistance to that association has also been documented, chiefly among Shigella spp. [20-25]. Additionally, ampicillin may fail clinically despite confirmed in vitro microbial susceptibility, because of its poor intracellular penetration. Amoxicillin is rapidly absorbed from the gastrointestinal tract, and therefore it is less effective than ampicillin for the treatment of infectious diarrhea.

TMP-SMX remains the drug of choice for the treatment of prolonged Aeromonas infections in most regions, though a 48% resistance rate has been reported from Taiwan [26]. That association may also remain an adequate choice for treating Yersinia infections, as no evidence of increasing resistance has been shown so far. However, one placebo-controlled study of TMP-SMX for the treatment of Yersinia infections showed no reduction in the duration of illness [27], though it decreased the duration of fecal shedding of the pathogen [28]. TMP-SMX may also remain an effective choice for the treatment of enterotoxigenic and enteropathogenic E. coli (ETEC and EPEC, respectively), in spite of growing resistance in several areas, chiefly among ETEC, which is a very common causative agent of travelers' diarrhea, especially in Latin America [29]. It may also remain a good choice for the treatment of cholera in children less than eight years old.

Chloramphenicol

Rising resistance rates, uncomfortable posology, and the risk of side effects, have contributed to the displacement of chloramphenicol as a good drug for the empirical treatment of acute diarrhea. Nevertheless, it still may be used empirically if typhoid fever is strongly suspected on clinical grounds, as long as it is supported by up-to-date knowledge of antimicrobial susceptibility pattern of locally circulating strains. The use of chloramphenicol for the treatment of typhoid fever is associated with reduced mortality and decreased incidence of life-threatening complications, but the need for a long two - three week regimen to prevent relapse and prolonged fecal shedding of pathogens is a significant drawback. Widespread plasmid-mediated resistance to chloramphenicol among typhoid Salmonella species became a clinical problem in the early 1970s [30,31], and both ampicillin and TMP-SMX were shown to be effective drugs to replace it until the late 1980s, when plasmid-mediated resistance to chloramphenicol, ampicillin and TMP-SMX was reported [32-34]. On the other hand, the re-emergence of chloramphenicol-susceptible strains has been reported from areas where the use of chloramphenicol had been avoided due to high resistance rates, possibly as a result of decreased selective pressure [35,36]. The occurrence of aplastic anemia is a very rare complication associated with the use of chloramphenicol, but it should always be kept in mind due to its potentially life-threatening severity [37,38].

Tetracyclines

In spite of their low cost and broad antimicrobial spectrum, the use of tetracyclines in pediatric patients is limited by permanent dental discoloration in children younger than eight years of age. The total dosage received appears to be the most important factor influencing the degree of staining, which has also been shown to depend upon the dosage and duration of therapy. Additionally, tetracyclines have been shown to cause enamel hypoplasia and reversibly impair bone growth. Because of these important side effects, tetracyclines have been progressively displaced by safer, equally effective drugs, for the treatment of most conditions in which they are likely to be effective. However, the benefits of therapy with a tetracycline can exceed the risks if alternative drugs are less efficacious or are associated with more significant side effects.

This is the case for cholera, for which the current standard antimicrobial therapy in adults is a single dose of fluoroquinolone, the use of which in children remains restricted. Oral tetracycline for three days or a single dose of doxycycline are the drugs of choice for the treatment of moderate to severe cases of cholera in patients older than eight years. Younger children may also profit from that therapy, in spite of the risk of dental staining, which has to be weighed against the benefits, i.e. decreases in the duration of diarrhea and in fluid replacement requirements. Whenever possible, the preferred tetracycline is doxycycline, because the risk of dental staining is less with this drug than with the other tetracyclines; in addition, it is given only twice a day. In the treatment of tetracycline-resistant strains, TMP-SMX has been used for children less than eight years of age who have cholera; ampicillin and macrolides may be reasonable alternatives.

Nalidixic Acid

Nalidixic acid, the only non-fluorinated quinolone available, was initially considered the best option to replace ampicillin and TMP-SMX [39,40]; but its widespread use was followed by increasing resistance in several countries, chiefly among Shigella spp. and, to a lesser extent, Salmonella [19,22,41-47]. However, in some regions there are still low rates of resistance, so it may still be a good option, especially because of its low cost and the possibility of oral use [23,48-51].

Besides increasing microbial resistance, two major problems for therapy with nalidixic acid are the regimen that should be used (four times a day for five days), which compromises compliance, and the fact that clinical and microbiological failure has been reported in 30% of patients infected with nalidixic acid-susceptible strains, possibly because of its poor cellular penetration when compared to fluorinated quinolones [39,52]. Nalidixic acid has been reported to damage juvenile weight-bearing joints in animal studies [53,54], but clinical studies have failed to demonstrate an association between the use of nalidixic acid and growth impairment or joint symptoms in humans, even with prolonged treatment [55,56].

Recently, resistance to nalidixic acid among Shigella and both typhoidal and non-typhoidal Salmonella has been shown to be a reliable predictive factor of clinically relevant decreased susceptibility to fluoroquinolones, which, on the other hand, cannot be considered fluoroquinolone resistance according to current guidelines [57-64].

Fluoroquinolones

The fluoroquinolones have become the drugs of choice for the empirical treatment of acute diarrhea in adults, because they are active against most of the common treatable enteropathogens, have excellent tissue and intracellular penetration, achieve high fecal concentrations, are suitable for oral administration, and have a favorable safety profile in adults [65,66]. The use of 500 mg ciprofloxacin twice a day for five days in the empirical therapy of acute diarrhea has been shown to decrease the duration of diarrhea, fecal shedding of pathogens, duration of fever and of other symptoms as well as total duration of illness, based on several randomized, placebo-controlled trials of various types of adult populations [67-71]. This decrease appears to be independent of the predominant pathogens that are isolated and of the rate of negative cultures from the study population, reflecting both the broad spectrum of activity of this drug and the low yield of stool cultures. Shorter three-day or even single-dose regimens of fluoroquinolones have been suggested to be effective for the treatment of shigellosis in adults and children [72-74]. Nevertheless, it is essential that clinicians be very selective in the cases in which they use fluoroquinolones, because the widespread unnecessary use of those drugs brings the risk of increasing microbial resistance to one of the few highly effective oral antimicrobial drugs currently available, as has been recently reported for some strains of Shigella, Salmonella and Campylobacter [75-80].

In children, though, there are several restrictions to the use of fluoroquinolones. Joint disorders observed in young experimental animals during experimental toxicity trials made pharmaceutical companies decide not to seek to extend fluoroquinolone indications to Pediatrics. Such side effects have also been noted in children participating on clinical trials [81-83] and, indeed, among all possible adverse effects of the use of fluoroquinolones, only musculoskeletal events are more common in children than in adults [84-87]. Based on the potential risks and benefits of prescribing fluoroquinolones to children, the American Academy of Pediatrics, as well as several experts, have suggested that fluoroquinolones only be prescribed for specific infections or as a second-line antibiotic, in the case of severe bacterial infections with proven resistance to safer drugs [88-92]. Therefore, it is not advisable to use fluoroquinolones for the empirical treatment of diarrhea in small children, though it may have a role in culture-oriented therapy. Further studies to precisely assess the cut-off age beyond which children may use fluoroquinolones safely are warranted.

Third Generation Cephalosporins

Since third generation cephalosporins have equally wide antimicrobial activity spectrum and fewer adverse effects than the fluoroquinolones, they have been considered by many the best drugs for the empirical treatment of severe acute infectious diarrhea in children; this is especially true for ceftriaxone, given the success rates similar to those achieved with the fluoroquinolones [83]. Ceftriaxone may be administered both intravenously and intramuscularly, typically for five days; but a two-day course has also been shown to be effective for shigellosis [93], but not for typhoid fever, which needs longer regimens [94]. Additionally, the clinical resolution of symptoms is typically slower with ceftriaxone than with ciprofloxacin, and more severe cases may require courses longer than five days. The effectiveness of ceftriaxone has been demonstrated in the treatment of both typhoid [95] and non-typhoid salmonellosis [96] and shigellosis [83,97], even with strains resistant to fluoroquinolones [98,99]. Besides the need for parenteral administration and the high cost, the major drawback of the widespread empirical use of ceftriaxone for the treatment of acute infectious diarrhea is the immediate danger of increasing microbial resistance to this useful drug. For all of these reasons, this drug should be reserved for very severe cases.

Cefixime is a third-generation cephalosporin that is administered orally; therefore, it may be an adequate drug for the treatment of outpatients. It is typically administered once or twice daily for five days, but it has been found that a two-day course is associated with rates of clinical cure similar to those achieved with a five-day course [100]. While a small trial found that therapy with cefixime failed in 47% of adults with shigellosis [101], others have reported high success rates with the use of cefixime for the treatment of childhood shigellosis and typhoid fever [95,102,103].

Azithromycin and Erythromycin

Oral azithromycin has been found to be a safe and effective alternative for the treatment of acute diarrhea due to a variety of etiologic agents, and it may be an interesting empirical choice due to its safety, comfortable once-daily posology and high cellular penetration. A five-day course of azithromycin has achieved similar cure rates and lower relapse rates than a five-day course of ceftriaxone in the treatment of uncomplicated typhoid fever in children and adolescents [104,105], and similar success rates have been found in a seven-day course comparison with chloramphenicol for the treatment of infections caused by chloramphenicol-susceptible strains [106]. Azithromycin, however, has the advantage of lower overall resistance rates. Azithromycin has also been compared with fluoroquinolones, and the results have indicated similar clinical and bacteriological effectiveness in cure and relapse rates and in defervescence in the treatment of typhoid fever caused by both sensitive and multidrug-resistant organisms [107,108]. It has also been observed that azithromycin can be more suitable than ofloxacin for the treatment of infections caused by nalidixic acid-resistant strains [108]. A single oral dose of 1 g has been shown to be as effective as a single 500 mg dose of levofloxacin in adults with traveler's diarrhea, achieving similarly high success rates [109].

While most cases of Campylobacter-associated diarrhea are self-limiting and do not require the use of antibiotics, patients with high fever, with bloody diarrhea, prolonged disease, pregnancy or those who are HIV-positive should be treated. Azithromycin has also been shown to be effective against Campylobacter-associated diarrhea in a region where fluoroquinolone-resistance is endemic [110], while erythromycin stearate is still considered the drug of choice for the treatment of Campylobacter enteritis in children, because of low overall resistance rates and lower cost. Erythromycin is also a good option for the treatment of severe cases of cholera in young children who should not take tetracyclines or fluoroquinolones. Additionally, resistance rates of Vibrio cholerae strains to tetracyclines, TMP-SMZ and ampicillin are high in several areas [111,112]. Azithromycin has been shown to be more effective for the treatment of shigellosis, than nalidixic acid [113] and cefixime [103] in children, and roughly as effective as ciprofloxacin in adults [114].

Metronidazole

Oral metronidazole is the first choice for the treatment of Clostridium difficile colitis, which is responsible for over 80% of antibiotic-associated cases of diarrhea, especially the most severe [115]. Such cases, however, account for only a small part of all cases of nosocomial diarrhea, which should not be empirically treated with metronidazole [116]. Several studies have found that the usual doses of metronidazole or vancomycin are equally efficacious against C. difficile-associated diarrhea, whereas some experts advocate the use of vancomycin for more severe cases [117,118]. As intravenous vancomycin is not satisfactorily efficacious against C. difficile, cases complicated by paralytic ileum or intestinal obstruction can be successfully treated with intravenous metronidazole, plus a vancomycin enema; but surgical evaluation is usually warranted. Therefore, the use of vancomycin may be avoided in order to prevent the selection of vancomycin-resistant strains, especially among enterococci.

Withdrawing the inciting antibiotic (generally a beta-lactam or a second or third generation cephalosporin) is a very important measure for the treatment of C. difficile colitis. Discontinuation of therapy is often enough to resolve mild presentations and must be accomplished as soon as possible in severe cases. Antimicrobial therapy is reserved for cases with increased severity or that persist after withdrawal of the inciting agent. Relapse is common a few weeks after clinical remission and frequently represents reinfection rather than therapeutic failure, so that the same antibiotic regimen can be used again. In spite of the efficacy of vancomycin, its use must be discouraged because of the ominous possibility of provoking the appearance of vancomycin-resistant strains.

Malabsorbed Agents

Because of concerns about growing resistance and side effects, great expectations have been raised for the use of antimicrobial agents that are not absorbed from the gastrointestinal tract and, therefore, tend to be associated with fairly low resistance rates and few adverse effects. Bicozamycin and oral aztreonam, albeit proven effective both in vitro and in vivo, have not become popular choices for the treatment of acute infectious diarrhea for a number of reasons [119-122].

The development of a broad-spectrum agent with such a favorable safety profile and a low tendency for increasing resistance would have a very positive impact, not only on the empirical treatment of severe diarrhea, but also on the therapy and prevention of travelers' diarrhea. Currently, rifaximin has been the focus of intense investigation, with exciting results. The effectiveness of rifaximin for the treatment of traveler's diarrhea has already been demonstrated in comparison with a placebo [123], with TMP-SMX [124] and with ciprofloxacin [125]. More data are needed to properly evaluate the efficacy of rifaximin for the treatment of severe invasive diarrhea.

Probiotics

Probiotics have been defined as living microorganisms that exert beneficial effects beyond their nutritional value upon ingestion in certain quantities [126]. Acid-lactic and non-pathogenic bacteria have been extensively used as probiotics, as has the non-pathogenic yeast Saccharomyces boulardii. Probiotic agents may be beneficial for the treatment of diarrhea through several mechanisms. These mechanisms vary from one agent to another; they include competition with enteropathogens for nutrition and adhesion, modification of bacterial toxins and/or their receptors and modulation of the host's immune response [127-131]. Several systematic reviews have addressed the role of probiotics in the treatment of acute diarrhea; generally it is agreed that probiotics reduce the duration of diarrhea when compared with a placebo, even though this may not be true for bacterial diarrhea [132-134]. There have been no reports of side effects so far. Further studies are warranted to determine exactly which probiotics are effective for each type of acute diarrhea. Additionally, several studies have investigated the role of probiotics for the prevention of community- and nosocomial-acquired diarrhea, antibiotic-associated diarrhea and travellers' diarrhea [135-138], but a discussion on those topics goes beyond the scope of this article.

Conclusion

There are plenty of antibiotics currently available for the treatment of acute infectious diarrhea in children (Table 1). While antibiotics are effective against most bacteria and may help shorten the duration of symptoms, it must always be kept in mind that antimicrobial therapy should be reserved for severe, prolonged or potentially complicated cases, as most patients respond fairly well to supportive therapy, and their indiscriminate use carries the danger of increasing antimicrobial resistance and brings no benefit to patients with mild presentations, as has been shown for uncomplicated salmonellosis [139]. Additionally, most diarrheal episodes affecting children are due to viruses, parasites, chemical agents and food intolerance, none of which requires antimicrobial therapy.

We reinforce the need for careful consideration of the use of antibiotics in the setting of acute diarrhea in children. The decision to start antimicrobial therapy should always be taken after adequate hydration and individual evaluation of various factors, including the likelihood of extra-intestinal dissemination of the infection and its severity. The empirical choice of the antimicrobial agent must be made individually for each case, considering the safety and the cost of the drugs, the pathogens most likely to be infecting the patient and up-to-date knowledge of the susceptibility pattern of locally circulating strains. In that context, large multicentric studies, such as SENTRY and RESISTNET [140,141], certainly play a role, but they do not replace smaller studies that more faithfully depict the situation in a given city or service.

We emphasize that most cases of acute diarrhea involve a self-limiting condition, requiring no more than supportive treatment with adequate hydration and nutrition that can be accomplished at home. The physician should make the patient's parents aware of warning signs that depict aggravation of the picture and the need for returning to the hospital for re-evaluation. The parents should also be informed about the routes of transmission of enteropathogens and about preventive measures.

While antibiotics may play a major part in reducing mortality among severely-ill patients, the ultimate approach against diarrhea in developing countries rests on the need for improving sanitary conditions, maintaining exclusive breastfeeding until the sixth month of life and developing safe and effective vaccines for immune prophylaxis, along with systematic parental education.

Received on 19 November 2005; revised 12 April 2006.

• 1. Kosek M., Bern C., Guerrant R.L. The global burden of diarrhoeal disease, as estimated from studies published between 1992 and 2000. Bull World Health Organ 2003;81:197-204.
• 2. Bern C., Martines J., de Zoysa I., Glass R.I. The magnitude of the global problem of diarrhoeal disease: A ten-year update. Bull World Health Organ 1992;70:705-14.
• ³
  World Health Organization. The management of bloody diarrhoea in young children. WHO, Geneva, Swizterland, 1994 (WHO/CDD/94.49).
• 4. Goodman L, Segreti J. Infectious diarrhea. Dis Mon 1999;45:268-99.
• 5. Carneiro N.B., Diniz-Santos D.R., Fagundes S.Q., et al. Clinical and epidemiological aspects of children hospitalized with severe rotavirus-associated gastroenteritis in Salvador, BA, Brazil. Braz J Infect Dis 2005;9:525-8.
• 6. Karadag A., Acikgoz Z.C., Avci Z., et al. Childhood diarrhoea in Ankara, Turkey: epidemiological and clinical features of rotavirus-positive versus rotavirus-negative cases. Scand J Infect Dis 2005;37:269-75.
• 7. Zhang X., McDaniel A., Wolf L., et al. Quinolone antibiotics induce shiga toxin-encoding bacteriophages, toxin production, and death in mice. J Infect Dis 2000;181:664-70.
• 8. Wong C.S., Jelacic S., Habeeb R.L., et al. The risk of hemolytic-uremic syndrome after antibiotic treatment of Escherichia coli O157:H7 infections. N Engl J Med 2000;342:1930-6.
• 9. Pal SC. Epidemic bacillary dysentery in West Bengal, India, 1984. Lancet 1984;1:1462.
• 10. Bennish M., Eusof A., Kay B., Wierzba T. Multiresistant Shigella infections in Bangladesh. Lancet 1985;2:441.
• 11. Sen D., Sengupta P.G., Bhattacharya S.K., et al. Epidemic Shiga bacillus dysentery in Port Blair, Andaman and Nicobar Islands, India. J Diarrhoeal Dis Res 1986;4:161-2.
• 12. Lolekha S., Vibulbandhitkit S., Poonyarit P. Response to antimicrobial therapy for shigellosis in Tahiland. Rev Infect Dis 1991;13(suppl 4):S342-6.
• 13. Frost J.A., Willshaw G.A., Berclay E.A., et al. Plasmid characterization of drug-resistant Shigella dysenteriae 1 from an epidemic in Central Africa. J Hyg 1985;94:163-72.
• 14. Mates A., Eyny D., Philo S. Antimicrobial resistance trends in Shigella serogroups isolated in Israel, 1990-1995. Eur J Clin Microbiol Infect Dis 2000;19:108-11.
• 15. Centers for Disease Control. Multiply resistant shigellosis in a day-care center _ Texas. MMWR 1986;35:753-5.
• 16. Centers for Disease Control. Nationwide dissemination of multiply resistant Shigella sonnei following a common-source outbreak. MMWR 1987;36:633-4.
• 17. Centers for Disease Control. Shigella dysenteriae type 1 - Guatemala, 1991. MMWR 1991;40:421-8.
• 18. Bratoeva M.P., John J.F., Jr. Dissemination of trimethoprim-resistant clones of Shigella sonnei in Bulgaria. J Infect Dis 1989;159:648-53.
• 19. Bennish M.L., Salam M.A., Hossain H.A., et al. Antimicrobial resistance to Shigella isolates in Bangladesh, 1983-1990: increasing frequency of strains multiply resistant to ampicillin, trimethoprim-sulphametoxazole and nalidixic acid. Clin Infect Dis 1992;14:1055-60.
• 20. Diniz-Santos D.R., Santana J.S., Barretto J.R., et al. Epidemiological and microbiological aspects of acute bacterial diarrhea in children from Salvador, Bahia, Brazil. Braz J Infect Dis 2005;9:75-81.
• 21. Aysev A.D., Guriz H. Drug resistance of Shigella strains isolated in Ankara, Turkey, 1993-1996. Scand J Infect Dis 1998;30:351-3.
• 22. Egah D.Z., Banwat E.B., Audu E.S., et al. Multiple drug resistant strains of Shigella isolated in Jos, central Nigeria. Niger Postgrad Med J 2003;10:154-6.
• 23. Anh N.T., Cam P.D., Dalsgaard A. Antimicrobial resistance of Shigella spp. isolated from diarrheal patients between 1989 and 1998 in Vietnam. Southeast Asian J Trop Med Public Health 2001;32:856-62.
• 24. Lima A.A., Lima N.L., Pinho M.C., et al. High frequency of strains multiply resistant to ampicillin, trimethoprim-sulfamethoxazole, streptomycin, chloramphenicol, and tetracycline isolated from patients with shigellosis in northeastern Brazil during the period 1988 to 1993. Antimicrob Agents Chemother 1995;39:256-9.
• 25. Putnam S.D., Riddle M.S., Wierzba T.A., et al. Antimicrobial susceptibility trends among Escherichia coli and Shigella spp. isolated from rural Egyptian paediatric populations with diarrhoea between 1995 and 2000. Clin Microbiol Infect 2004;10: 804_10.
• 26. Ko W.C., Yu K.W., Liu C.Y., et al. Increasing antibiotic resistance in clinical isolates of Aeromonas strains in Taiwan. Antimicrob Agents Chemother 1996;40:1260-2.
• 27. Pai C., Gillis F., Tuomanen E., Marks M.I. Placebo controlled double-blind evaluation of trimethoprim-sulfamethoxazole treatment of Yersinia enterocolitica gastroenteritis. J Pediatr 1984;104:308-11.
• 28. Marks M.I., Pai C.H., Lafleur L., et al. Yersinia enterocolitica gastroenteritis: a prospective study of clinical, bacteriologic, and epidemiologic features. J Pediatr 1980;96:26-31.
• 29. Black R.E. Epidemiology of travelers' diarrhea and relative importance of various pathogens. Rev Infect Dis 1990;12(Suppl1):S73-9.
• 30. Gangarosa E.J., Bennett J.V., Wyatt C., et al. An epidemic-associated episome? J Infect Dis 1972;126:215-8.
• 31. Butler T., Linh N.N., Arnold K., Pollack M. Chloramphenicol-resistant typhoid fever in Vietnam associated with R factor. Lancet 1973;2:983-5.
• 32. Kamili M.A., Ali G., Shah S.Y., et al. Multiple drug resistant typhoid fever outbreak in Kashmir Valley. Indian J Med Sci 1993;47:147-51.
• 33. Anand A.C. The anatomy of an epidemic (the final report on an epidemic of multidrug resistant enteric fever in eastern India). Trop Gastroenterol 1993;14:21-7.
• 34. Uwaydah A.K., Matar I., Chacko K.C., Davidson J.C. The emergence of antimicrobial resistant Salmonella typhi in Qatar: epidemiology and therapeutic implications. Trans R Soc Trop Med Hyg 1991;85:790-2.
• 35. Sood S., Kapil A., Das B., et al. Re-emergence of chloramphenicol-sensitive Salmonella typhi Lancet 1999;353:1241-2.
• 36. Chandra J., Marwaha R.K., Sachdeva S. Chloramphenicol-resistant Salmonella typhi: therapeutic considerations. Indian J Pediatr 1984;51:567-70.
• 37. West B.C., DeVault G.A. Jr., Clement J.C., Williams D.M. Aplastic anemia associated with parenteral chloramphenicol: review of 10 cases, including the second case of possible increased risk with cimetidine. Rev Infect Dis 1988;10:1048-51.
• 38. Abbas Z., Malik I., Khan A. Sequential induction of aplastic anemia and acute leukemia by chloramphenicol. J Pak Med Assoc 1993;43:58-9.
• 39. Salam M.A., Bennish M.L. Therapy for shigellosis. I. Randomized, double-blind trial of nalidixic-acid in childhood shigellosis. J Pediatr 1988;113:901-7.
• 40. Bhattacharya S.K., Datta P., Datta D., et al. Relative efficacy of trimethoprim-sulfamethoxazole and nalidixic acid for acute invasive diarrhea. Antimicrob Agents Chemother 1987;31:837.
• 41. Munshi M.H., Sack D.A., Haider K., et al. Plasmid-mediated resistance to nalidixic-acid in Shigella dysenteriae type 1. Lancet 1987;2:419-21.
• 42. Dagan D., Orr N., Yavzori M., et al. Retrospective analysis of the first clonal outbreak of nalidixic acid-resistant Shigella sonnei shigellosis in Israel. Eur J Clin Microbiol Infect Dis 2002;21:887-9.
• 43. Ghosh A.R., Sugunan A.P., Sehgal S.C., Bharadwaj A.P. Emergence of nalidixic acid-resistant Shigella sonnei in acute-diarrhea patients on Andaman and Nicobar Islands, India. Antimicrob Agents Chemother 2003;47:1483.
• 44. Cheasty T., Day M., Threlfall E.J. Increasing incidence of resistance to nalidixic acid in shigellas from humans in England and Wales: implications for therapy. Clin Microbiol Infect 2004;10:1033-5.
• 45. Panhotra B.R., Saxena A.K., Al-Mulhim K. Emergence of nalidixic acid resistance in Shigella sonnei isolated from patients having acute diarrheal disease: report from Eastern Province of Saudi Arabia. Jpn J Infect Dis 2004;57:116-8.
• 46. Panhotra B.R., Saxena A.K., Al-Ghamdi A.M. Emerging nalidixic acid and ciprofloxacin resistance in non-typhoidal Salmonella isolated from patients having acute diarrhoeal disease. Ann Saudi Med 2004;24:332-6.
• 47. Parry C.M., Wain J., Chinh N.T., et al. Quinolone-resistant Salmonella typhi in Vietnam. Lancet 1998;351:1289.
• 48. Murphy T.M., McNamara E., Hill M., et al. Epidemiological studies of human and animal Salmonella typhimurium DT104 and DT104b isolated in Ireland. Epidemiol Infect 2001;126:3-9.
• 49. Gorman R., Adley C.C. Nalidixic acid-resistant strains of Salmonella showing decreased susceptibility to fluoroquinolones in the mid-west region of the Republic of Ireland. J Antimicrob Chemother 2003;51:1047-9.
• 50. Mahmood A. Nalidixic acid is still the drug of choice for shigellosis in Pakistan. J Pak Med Assoc 2001;51:101.
• 51. MoezArdalan K., Zali M.R., Dallal M.M., et al. Prevalence and pattern of antimicrobial resistance of Shigella species among patients with acute diarrhoea in Karaj, Tehran, Iran. J Health Popul Nutr 2003;21:96-102.
• 52. Alam A.N., Islam M.R., Hossain M.S., et al. Comparison of pivmecillinam and nalidixic acid in the treatment of acute shigellosis in children. Scand J Gastroenterol 1994;29:313-7.
• 53. Bouissou H., Caujolle D., Caujolle F., Milhaud G. Tissus cartilagineux et acide nalidixique. C R Acad Sc Paris 1978;23:1743-6.
• 54. Brand H.S., van Kampen G.P., van der Korst J.K. Effect of nalidixic acid, pipemidic acid and cinoxacin on chondrocyte metabolism in explants of articular cartilage. Clin Exp Rheumatol 1990;8:393-5.
• 55. Nuutinen M., Turtinen J., Uhari M. Growth and joint symptoms in children treated with nalidixic acid. Pediatr Infect Dis J 1994;13:798-800.
• 56. Schaad U.B., Wedgwood-Krucko J. Nalidixic acid in children: retrospective matched controlled study for cartilage toxicity. Infection 1987;15:165-8.
• 57. Hirose K, Terajima J, Izumiya H, et al. Antimicrobial susceptibility of Shigella sonnei isolates in Japan and molecular analysis of S. sonnei isolates with reduced susceptibility to fluoroquinolones. Antimicrob Agents Chemother 2005;49:1203-5.
• 58. Albayrak F., Cokca F., Erdem B., Aysev A.D. Predictive value of nalidixic acid resistance for detecting salmonellae with decreased ciprofloxacin susceptibility. Int J Antimicrob Agents 2004;23:332-6.
• 59. Anjum P., Qureshi A.H., Rafi S. Fluoroquinolone resistance in typhoidal Salmonella and its detection by nalidixic acid disc diffusion. J Pak Med Assoc 2004;54:295-301.
• 60. Asna S.M., Haq J.A., Rahman M.M. Nalidixic acid-resistant Salmonella enterica serovar Typhi with decreased susceptibility to ciprofloxacin caused treatment failure: a report from Bangladesh. Jpn J Infect Dis 2003;56:32-3.
• 61. Kapil A., Das B. Nalidixic acid susceptibility test to screen ciprofloxacin resistance in Salmonella typhi Indian J Med Res 2002;115:49-54.
• 62. Oteo J., Aracil B., Alos J.I., Gomes-Garcez J.L. High rate of resistance to nalidixic acid in Salmonella enterica: its role as a marker of resistance to fluoroquinolones. Clin Microbiol Infect 2000;6:273-6.
• 63. Hakanen A., Kotilainen P., Jalava J., et al. Detection of decreased fluoroquinolone susceptibility in salmonellas and validation of nalidixic acid screening test. J Clin Microbiol 1999;37:3572-7.
• ⁶⁴
  National Committee for Clinical Laboratory Standards. Performance standards for antimicrobial susceptibility testing: ninth informational (suppl.). Approved Standard M100-S9. Villanova, PA: National Committee for Clinical Laboratory Standards, 1999
• 65. Hopper D.C., Wolfson J.S. Fluoroquinolone antimicrobial agents. N Engl J Med 1991;324:384-94.
• 66. Akalin H.E. Quinolones in the treatment of acute bacterial diarrhoeal diseases. Drugs 1993;45(Suppl 3):114-8.
• 67. Pichler H.E., Diridl G., Stickler K., Wolf D. Clinical efficacy of ciprofloxacin compared with placebo in bacterial diarrhea. Am J Med 1987;82:329-32.
• 68. Pichler H.E., Diridl G., Wolf D. Ciprofloxacin in the treatment of acute bacterial diarrhea: a double-blind study. Eur J Clin Microbiol 1986;5:241-3.
• 69. Goodman L.J., Trenholme G.M., Kaplan R.L., et al. Empiric antimicrobial therapy of domestically acquired acute diarrhea in urban adults. Arch Intern Med 1990;150:541-6.
• 70. Dryden M.S., Gabb R.J., Wright S.K. Empirical treatment of severe acute community-acquired gastroenteritis with ciprofloxacin. Clin Infect Dis 1996;22:1019-25.
• 71. Wistrom J., Jertborn M., Ekwall E., et al. Empiric treatment of acute diarrheal disease with norfloxacin: a randomized, placebo-controlled study. Swedish Study Group. Ann Intern Med 1992;117:202-8.
• 72. Bennish M.L., Salam M.A., Kahn W.A., et al. Treatment of shigellosis: III. Comparison of one and two dose ciprofloxacin with standard 5 day treatment. A randomized, blinded trial. Ann Inter Med 1992;117:727-34.
• 73. Guyon P., Cassel-Beraud A.M., Rakotonirina G., Gendrel D. Short treatment with pefloxacin in Madagascan children with shigellosis due to multiresistant organisms. Clin Infect Dis 1994;19:1172-3.
• 74. Gendrel D., Moreno J.L., Nduwimana M., et al. One-dose treatment with pefloxacin for infection with multidrug-resistant Shigella dysenteriae type 1 in Burundi. Clin Infect Dis 1997;24:83.
• 75. Hakanen A., Siitonen A., Kotilainen P., Huovinen P. Increasing fluoroquinolone resistance in salmonella serotypes in Finland during 1995-1997. J Antimicrob Chemother 1999;43:145-8.
• 76. Molbak K., Baggesen D.L., Aarestrup F.M., et al. An outbreak of multidrug-resistant, quinolone-resistant Salmonella enterica serotype typhimurium DT104. N Engl J Med 1999;349:1420-5.
• 77. Dutta S., Dutta P., Matsushita S., et al. Shigella dysenteriae serotype 1, Kolkata, India. Emerg Infect Dis 2003;9:1471-4.
• 78. Nakaya H., Yasuhara A., Yoshimura K., et al. Life-threatening infantile diarrhea from fluoroquinolone-resistant Salmonella enterica typhimurium with mutations in both gyrA and parC. Emerg Infect Dis 2003;9:255-7.
• 79. Hoge C.W., Gambel J.M., Srijan A., et al. Trends in antibiotic resistance among diarrheal pathogens isolated in Thailand over 15 years. Clin Infect Dis 1998;26:341-5.
• 80. Hakanen A., Jousimies-Somer H., Siitonen A., et al. Fluoroquinolone resistance in Campylobacter jejuni isolates in travelers returning to Finland: association of ciprofloxacin resistance to travel destination. Emerg Infect Dis 2003;9:267-70.
• 81. Black A., Redmond A.O., Steen H.I., Oborska I.T. Tolerance and safety of ciprofloxacin in pediatric patients. J Antimicrob Chemother 1990;26:25-9.
• 82. Hampel B., Hullmann R., Schmidt H. Ciprofloxacin in paediatrics: worldwide clinical experience based on compassionate use _ safety report. Pediatr Infect Dis J 1997;16:127-9.
• 83. Leibovitz E., Janco J., Piglanski L., et al. Oral ciprofloxacin versus intramuscular ceftriaxone as empiric treatment of acute invasive diarrhea in children. Pediatr Infect Dis J 2000;19:1060-7.
• 84. Ball P., Tillotson G. Tolerability of fluoroquinolone antibiotics. Past, present and future. Drug Saf 1995;13:343-58.
• 85. Rahm V., Schacht P. Safety of ciprofloxacin. A review. Scand J Infect Dis Suppl 1989;60:120-8.
• 86. Chysky V., Kapila K., Hullmann R., et al. Safety of ciprofloxacin in children: worldwide clinical experience based on compassionate use. Emphasis on joint evaluation. Infection 1991;19:289-96.
• 87. Chalumeau M., Tonnelier S., d'Athis P., et al. Fluoroquinolone safety in pediatric patients: a prospective, multicenter comparative cohort study in France. Pediatrics 2003;111:714-9.
• 88. American Academy of Pediatrics. Fluoroquinolones. In: Pickering LK, ed. Red Book: 2003 Report of the Committee on Infectious Diseases. 26^th ed. Elk Groove Village, IL: American Academy of Pediatrics 2003:693-4.
• 89. Gendrel D., Chalumeau M., Moulin F., Raymond J. Fluoroquinolones in paediatrics: a risk for the patient or for the community? Lancet Infect Dis 2003;3:537-46.
• 90. Schaad U.B., Abdus-Salam M., Aujard Y., et al. Use of fluoroquinolones in pediatrics: consensus report of an International Society of Chemotherapy Commission. Pediatr Infect Dis J 1995;14:1-9.
• 91. Schaad UB. Pediatric use of quinolones. Pediatr Infect Dis J 1999;18:469-70.
• 92. Aradottir E., Yogev R. the use of fluoroquinolones in pediatrics _ a reassessment. Semin Pediatr Infect Dis 1999;10:31-37.
• 93. Eidlitz-Marcus T., Cohen Y.H., Nussinovitch M., et al. Comparative efficacy of two- and five-day courses of ceftriaxone for treatment of severe shigellosis in children. J Pediatr 1993;123:822-4.
• 94. Bhutta Z.A., Khan I.A., Shadmani M. Failure of short-course ceftriaxone chemotherapy for multidrug-resistant typhoid fever in children: a randomized controlled trial in Pakistan. Antimicrob Agents Chemother 2000;44:450-2.
• 95. Girgis N.I., Sultan Y., Hammad O., Farid Z. Comparison of the efficacy, safety and cost of cefixime, ceftriaxone and aztreonam in the treatment of multidrug-resistant Salmonella typhi septicemia in children. Pediatr Infect Dis J 1995;14:603-5.
• 96. Lin T.Y., Chiu C.H., Lin P.Y., et al. Short-term ceftriaxone therapy for treatment of severe non-typhoidal Salmonella enterocolitis Acta Paediatr 2003;92:537-40.
• 97. Varsano I., Eidlitz-Marcus T., Nussinovitch M., Elian I. Comparative efficacy of ceftriaxone and ampicillin for treatment of severe shigellosis in children. J Pediatr 1991;118:627-32.
• 98. Dutta P., Mitra U., Dutta S., et al. Ceftriaxone therapy in ciprofloxacin treatment failure typhoid fever in children. Indian J Med Res 2001;113:210-3.
• 99. Butt T., Ahmad R.N., Mahmood A., Zaidi S. Ciprofloxacin treatment failure in typhoid fever case, Pakistan. Emerg Infect Dis 2003;9:1621-2.
• 100. Martin J.M., Pitetti R., Maffei F., et al. Treatment of shigellosis with cefixime: two days versus five days. Pediatr Infect Dis J 2000;19:522-6.
• 101. Salam M.A., Seas C., Khan W.A., Bennish M.L. Treatment of shigellosis: IV. Cefixime is ineffective in shigellosis in adults. Ann Intern Med 1995;123:505-8.
• 102. Ashkenazi S., Amir J., Waisman Y., et al. A randomized, double-blind study comparing cefixime and trimethoprim-sulfamethoxazole in the treatment of childhood shigellosis. J Pediatr 1993;123:817-21.
• 103. Basualdo W., Arbo A. Randomized comparison of azithromycin versus cefixime for treatment of shigellosis in children. Pediatr Infect Dis J 2003;22:374-7.
• 104. Frenck R.W. Jr., Mansour A., Nakhla I., et al. Short-course azithromycin for the treatment of uncomplicated typhoid fever in children and adolescents. Clin Infect Dis 2004;38:951-7.
• 105. Frenck R.W. Jr., Nakhla I., Sultan Y., et al. Azithromycin versus ceftriaxone for the treatment of uncomplicated typhoid fever in children. Clin Infect Dis 2000;31:1134-8.
• 106. Butler T., Sridhar C.B., Daga M.K., et al. Treatment of typhoid fever with azithromycin versus chloramphenicol in a randomized multicentre trial in India. J Antimicrob Chemother 1999;44:243-50.
• 107. Girgis N.I., Butler T., Frenck R.W., et al. Azithromycin versus ciprofloxacin for treatment of uncomplicated typhoid fever in a randomized trial in Egypt that included patients with multidrug resistance. Antimicrob Agents Chemother 1999;43:1441-4.
• 108. Chinh N.T., Parry C.M., Ly N.T., et al. A randomized controlled comparison of azithromycin and ofloxacin for treatment of multidrug-resistant or nalidixic acid-resistant enteric fever. Antimicrob Agents Chemother 2000;44:1855-9.
• 109. Adachi J.A., Ericsson C.D., Jiang Z.D., et al. Azithromycin found to be comparable to levofloxacin for the treatment of US travelers with acute diarrhea acquired in Mexico. Clin Infect Dis 2003;37:1165-71.
• 110. Kuschner R.A., Trofa A.F., Thomas R.J., et al. Use of azithromycin for the treatment of Campylobacter enteritis in travelers to Thailand, an area where ciprofloxacin resistance is prevalent. Clin Infect Dis 1995;21:536-41.
• 111. Anand V., Arora S., Patwari A., et al. Multidrug resistance in Vibrio cholerae Indian Pediatr 1996;33:774-7.
• 112. Siddique A.K., Salam M., Islam M.S., et al. Why treatment centers failed to prevent cholera deaths among Rwandan refugees in Goma, Zaire. Lancet 1995;345:359-61
• 113. Miron D., Torem M., Merom R., Colodner R. Azithromycin as an alternative to nalidixic acid in the therapy of childhood shigellosis. Pediatr Infect Dis J 2003;23:367-8.
• 114. Khan W.A., Seas C., Dhar U., et al. Treatment of shigellosis: V. Comparison of azithromycin and ciprofloxacin: a double-blind, randomized, controlled trial. Ann Inter Med 1997;126:697-703.
• 115. Hogenauer C., Hammer H.F., Krejs G.J., Reisinger E.C. Mechanisms and management of antibiotic-associated diarrhea. Clin Infect Dis 1998;27:702-10.
• 116. Vasa C.V., Glatt A.E. Effectiveness and appropriateness of empiric metronidazole for Clostridium difficile-associated diarrhea. Am J Gastroenterol 2003;98:354-8.
• 117. Wenisch C., Parschalk B., Hasenhundl M., et al. Comparison of vancomycin, teicoplanin, metronidazole and fusidic acid for the treatment of Clostridium difficile diarrhea. Clin Infect Dis 1996;23:813-8.
• 118. Fekety R. Guidelines for the diagnosis and treatment of Clostridium difficile-associated diarrhea and colitis American College of Gastroenterology, Practice Parameters Committee. Am J Gastroenterol 1997;92:739-50.
• 119. Vanhoof R., Coignau H., Stas G., et al. Activity of bicozamycin (CGP 3543/E) on different enteropathogenic micro-organisms: comparison with other antimicrobial agents. J Antimicrob Chemother 1982;10:343-6.
• 120. Ericsson C.D., DuPont H.L., Sullivan P., et al. Bicozamycin, a poorly absorbable antibiotic, effectively treats travelers' diarrhea. Ann Intern Med 1983;98:20-5.
• 121. Goossens H., DeMol P., Coignau H., et al. Comparative in vitro activities of aztreonam, ciprofloxacin, norfloxacin, ofloxacin, HR 810 (a new cephalosporin), RU 28965 (a new macrolide) and other agents against enteropathogens. Antimicrob Agents Chemother 1985;27:388-92.
• 122. DuPont H.L., Ericsson C.D., Mathewson J.J., et al. Oral aztreonam, a poorly absorbed yet effective therapy for bacterial diarrhea in US travelers to Mexico. JAMA 1992;267:1932-5.
• 123. Steffen R., Sack D.A., Riopel L., et al. Therapy of travelers' diarrhea with rifaximin on various continents. Am J Gastroenterol 2003;98:1073-8.
• 124. DuPont H.L., Ericsson C.D., Matthewson J.J., et al. Rifaximin: a nonabsorbed antimicrobial in the therapy of travelers' diarrhea. Digestion 1998;59:708-14.
• 125. DuPont H.L., Jiang Z.D., Ericsson C.D., et al. Rifaximin versus ciprofloxacin for the treatment of travelers' diarrhea: a randomized, double-blind clinical trial. Clin Infect Dis 2001;33:1807-15.
• 126. Guarner F., Schaafsma G.J. Probiotics. Int J Food Microbiol 1998;39:237-8.
• 127. Wilson K.H., Perini I. Role of competition for nutrients in suppression of Clostridium difficile by the colonic microflora. Infect Immunol 1988;56:2610-4.
• 128. Walker W.A. Role of nutrients and bacterial colonization in the development of intestinal host defense. J Pediatr Gastroenterol Nutr 2000;30(suppl):S2-7.
• 129. Bernet M.F., Brassart D., Neeser J.R., et al. Lactobacillus acidophilus LA 1 binds to cultured human intestinal cell lines and inhibits cell attachment and cell invasion by enterovirulent bactéria. Gut 1994;35:483-9.
• 130. Michail S., Abernathy F. Lactobacillus plantarum inhibits the intestinal epithelial migration of neutrophils induced by enteropathogenic Escherichia coli J Pediatr Gastroenterol Nutr 2003;36:385-91.
• 131. Michail S., Abernathy F. Lactobacillus plantarum reduces the in vitro secretory response of intestinal epithelial cells to enteropathogenic Escherichia coli infection. J Pediatr Gastroenterol Nutr 2003;35:350-5
• 132. Szajewska H., Mrukowicz J.Z. Probiotics in the treatment and prevention of acute infectious diarrhea in infants and children: a systematic review of published randomized, double-blind, placebo-controlled trials. J Pediatr Gastroenterol Nutr 2001;33(Suppl 2):S17-25.
• 133. Van Niel C., Feudtner C., Garrison M.M., Christakis D.A. Lactobacillus therapy for acute infectious diarrhea in children: a meta-analysis. Pediatrics 2002;109:678-84.
• 134. Huang J.S., Bousvaros A., Lee J.W., et al. Efficacy of probiotic use in acute diarrhea in children. A meta-analysis. Dis Dis Sci 2002;47:2625-34.
• 135. Hatakka K., Savilahti R., Ponka A., et al. Effect of long term consumption of probiotic milk on infections in children attending day care centers: double-blind randomized trial. BMJ 2001;322:1-5.
• 136. Szajewska H., Kotowska M., Mrukowicz J.Z., et al. Efficacy of Lactobacillus GG in prevention of nosocomial diarrhea in infants. J Pediatr 2001;138:361-5.
• 137. Szajewska H., Mrukowicz J. Meta-analysis: non-pathogenic yeast Saccharomyces boulardii in the prevention of antibiotic-associated diarrhoea. Aliment Pharmacol Ther 2005;22:365-72.
• 138. Marteau P.R., de Vrese M., Cellier C.J., et al. Protection from gastrointestinal diseases with the use of probiotics. Am J Clin Nutr 2001;73(suppl):430-6.
• 139. Chiu C.H., Lin T.Y., Ou J.T. A clinical trial comparing oral azithromycin, cefixime and no antibiotics in the treatment of acute uncomplicated Salmonella enteritis in children. Paediatr Child Health 1999;35:372-4.
• 140. Sader H.S., Jones R.N., Gales A.C., et al. SENTRY antimicrobial surveillance program report: Latin American and Brazilian results for 1997 through 2001. Braz J Infect Dis 2004;8:25-79.
• 141. Oplustil C.P., Nunes R., Mendes C., RESISTNET Group. Multicenter evaluation of resistance patterns of Klebsiella pneumoniae, Escherichia coli, Salmonella spp., and Shigella spp. isolated from clinical specimens in Brazil: RESISTNET surveillance program. Braz J Infect Dis 2001;5:8-12.

Publication Dates

• Publication in this collection
  18 Sept 2006
• Date of issue
  June 2006

History

• Reviewed
  12 Apr 2006
• Received
  19 Nov 2005