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OBJECTIVE: Activation of nuclear factor kappaB by diverse bacteria regulates the secretion of chemokines and cytokines. Staphylococcus aureus (S. aureus)-infected osteoblasts can significantly increase the secretion of interleukin-6 and monocyte chemoattractant protein-1. The aim of this study was to investigate whether S. aureus can activate nuclear factor kappaB in human osteoblasts, and whether the activation of nuclear factor kappaB by S. aureus regulates the secretion of interleukin-6 and monocyte chemoattractant protein-1. METHODS: Immunoblot and electrophoretic mobility shift assay were used to detect the degradation of IκBa and activation of nuclear factor kappaB in human osteoblasts in response to S. aureus, respectively. Enzyme-linked immunosorbent assay was used to measure the secretion of interleukin-6 and monocyte chemoattractant protein-1 in the supernatants. Lastly, carbobenzoxyl-l-leucinyl-l-leucinyl-l-leucinal, an inhibitor of the nuclear factor kappaB, was used to determine if activation of nuclear factor kappaB by S. aureus in human osteoblasts regulates the secretions of interleukin-6 and monocyte chemoattractant protein-1. RESULTS: Our results for the first time demonstrated that S. aureus can induce the degradation of IκBa and activation of nuclear factor kappaB in human osteoblasts in a time and dose-dependent manner. In addition, inhibition of nuclear factor kappaB by carbobenzoxyl-l-leucinyl-l-leucinyl-l-leucinal suppressed the secretion of interleukin-6 and monocyte chemoattractant protein-1 in the supernatants of S. aureus-infected human osteoblasts in a dose-dependent manner. CONCLUSION: These findings suggest that S. aureus can activate nuclear factor kappaB in human osteoblasts, and subsequently regulate the secretion of interleukin-6 and monocyte chemoattractant protein-1. The nuclear factor kappaB transcription factor regulates a number of genes involved in a wide variety of biological processes. Further study of the effects of nuclear factor kappaB activation on S. aureus-infected human osteoblast may provide us new insights into discovery of the immune mechanisms in osteomyelitis.

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Infection by Pseudomonas aeruginosa has spread worldwide, with limited options for treatment. The purpose of this study was to investigate metallo-β-lactamase-producing P. aeruginosa strains and compare their genetic profile using samples collected from patients in intensive care units. Forty P. aeruginosa strains were isolated from two public hospitals in Campo Grande, Mato Grosso do Sul State, from January 1st, 2007 to June 31st, 2008. Profiles of antimicrobial susceptibility were determined using the agar diffusion method. Metallo-β-lactamase was investigated using the double-disk diffusion test and PCR. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE). Respiratory and urinary tracts were the most common isolation sites. Of the 40 samples tested, 72.5% (29/40) were resistant to ceftazidime and 92.5% (37/40) to imipenem, whereas 65% (26/40) were resistant to both antimicrobials. Fifteen pan-resistant samples were found. Five percent (2/40) of samples were positive for metallo-β-lactamase on the phenotype test. No metallo-β-lactamase subtype was detected by PCR. Macrorestriction analysis revealed 14 distinct genetic patterns. Based on the superior accuracy of PCR, it can be inferred that P. aeruginosa isolates from the investigated hospitals have alternative mechanisms of carbapenem resistance. The results also suggest clonal spread of P. aeruginosa between the studied hospitals.

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OBJECTIVE: The purpose of the present research was to compare the residual microbial load in Solo System microfiber mops with silver and in normal microfiber mops without silver to see whether those with the silver prevent bacterial proliferation and spread more effectively during normal cleaning operations. METHODS: Mops with and without silver were experimentally contaminated with suspension of Staphylococcus aureus ATCC 6538. The bioburden was evaluated by a filtering procedure according to UNI EN 1174 after contamination, after washing and after different times of impregnation in an alcohol-base detergent. RESULTS AND DISCUSSION: The results obtained lead to the conclusion that silver microfiber mop was significantly more effective in reducing bacterial load despite initial high level contamination (10(6)-10(7) CFU/50 cm²). Indeed, after low temperature washing, the bacterial load was already completely eliminated while the mop without silver still presented relatively high levels of the microorganism (approximately 10² CFU/50 cm²) even after being soaked for 8 hours in a detergent/disinfectant.

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OBJECTIVE: The objective of this study was to analyze different primers that are commonly used in epidemiological studies for the detection of Leishmania DNA by PCR, and to compare them to the conventional direct parasite search for American cutaneous leishmaniasis (ACL) diagnosis. MATERIAL AND METHODS: Five pairs of primers, four of them derived from Leishmania kDNA sequences (MP3H-MP1L; B1-B2; LBF1-LBR1; 13A-13B), and one derived from the SL RNA (mini-exon) gene repeat (LU5A-LB3C), reported previously, were used. RESULTS: The MP3H-MP1L primers were the best at amplifying the DNA, detecting 2 fg of Leishmania spp. DNA. The 13A-13B primers presented the worst performance, detecting 512 x 10³ fg of DNA. CONCLUSION: The wide variation in the analytical sensitivity of the primers used in the PCR, and the significant differences from the conventional method of ACL diagnosis found in this study, emphasize the importance of standardizing the PCR technique, analyzing sensitivity, and selecting suitable oligonucleotide primers.

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Diagnosis of herpes simplex encephalitis (HSE) is based on the detection of herpes simplex virus (HSV) DNA in patients' CSF samples. HSV DNA quantitation has the potential for estimating the effects of antiviral therapy. The aim of this study was to diagnose HSV DNA in HSE suspected patients and the quantitative analysis of its genome using real-time PCR to assess the value of the viral load in the course of antiviral treatment. The CSF samples were collected from 236 consecutive HSE suspected patients from November 2004 to May 2008. Upon DNA extraction, the samples were analyzed by Real-Time PCR assay. A set of primers amplified a common sequence of HSV glycoprotein B gene. The copy numbers of unknown samples were expressed via a standard curve drawn with a known amount of amplified cloned plasmid. Of the 236 samples, 137 (58%) came from males and 99 (42%) from females. The HSV genome was detected in 22 (9.3%) patients by PCR, 13 males/ 9 females. Serial CSF samples were available from 10 of the 22 patients. The range of the HSV DNA copy numbers in the clinical samples ranged from 2.5 × 10² to 1.7 × 10(6) copies/mL of CSF. Quantitative PCR results can be helpful in evaluating the efficacy of antiviral therapy in the above-mentioned patients. There is an association between the initial viral load and the duration of treatment course.

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BACKGROUND AND OBJECTIVES: Rotavirus (RV) is the main etiological agent of diarrhea in childhood; its laboratory diagnosis is crucial to guide the clinical management and prevention of its spread. RV immunization was introduced in Brazilian 6-month-old children in 2006. The present study was aimed to evaluate three methodologies used for human RV detection in stool samples obtained from patients hospitalized due to gastroenteritis in a teaching hospital and report the impact of RV immunization in hospitalization by diarrhea. METHODS: 293 stool samples collected in the 2001-2008 period were analyzed by enzyme immunoassay (EIA), latex agglutination (LA) and polyacrylamide gel electrophoresis (PAGE). RESULTS: Rotavirus was detected in 34.8% of samples by LA assay, 28.3% of samples by EIA assay and in 25.6% of samples by PAGE assay. Considering the PAGE method as gold standard, the sensitivity, specificity and accuracy of EIA were 94.6%, 94.4% and 94.5%, and to LA were 82.6%, 81.6% and 81.9%, respectively. CONCLUSION: These results indicate that antigen detection by EIA is a rapid, sensitive and specific method, and could be used in large-scale applications for screening stool samples suspected of RV infection. This study showed decreased incidence of RV infection in hospitalized children prior to the implementation of the national immunization program against RV.

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INTRODUCTION: During the first pandemic wave of the influenza A H1N1 2009 virus, morbidity was particularly high in Brazil. Hospitalizations resulting from severe respiratory disease due to suspected influenza-like illness created an opportunity to identify other respiratory viruses causing lower respiratory infections. OBJECTIVE: The purpose of this study was to assess viral etiologies among samples collected during the first pandemic wave of H1N1 2009 from hospitalized patients with suspected cases in a Brazilian Sentinel Hospital. PATIENTS AND METHODS: Viral etiologies were investigated in samples from 98 children and 61 adults with fever, cough and dyspnea who were admitted to São Paulo Sentinel Hospital with suspected H1N1 infection. RESULTS: From August to November 2009, in 19.5% (31/159) of the samples 2009 H1N1 virus was detected with 23% (14/61) in adults (median age 25 years, range: 14-55 years) and 18.4% (17/92) in children (median age 5 years, range: 4 months - 11 years). Among the negative samples, a wide range of causative etiologic agents was identified. Human rhinovirus was the most frequent virus (23.91%) in children and human metapneumovirus (11.48%) was the second most frequent in adults, following 2009 H1N1 virus (22.95%). CONCLUSION: These data highlight the need to diagnose other viral infections that can co-circulate with influenza and may have been neglected by physicians as causes of severe respiratory diseases.

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BACKGROUND AND AIM: Chronic hepatitis B is a highly prevalent disease worldwide, leading to serious consequences if not properly treated. Six treatment options for chronic hepatitis B are currently provided by the Brazilian public health system. Telbivudine is a nucleoside analogue that is neither included in the Brazilian clinical protocol nor in the therapeutic guidelines for chronic hepatitis B. OBJECTIVE: The aim of this study was to evaluate the cost-effectiveness of telbivudine for the viewpoint of the Brazilian public system, comparing it to lamivudine. METHODS: A Markov model was used to project lifetime complications and costs of treatment with lamivudine or telbivudine for chronic hepatitis B in both HBeAg-positive and HBeAg-negative patients. To evaluate disease progression, probabilities and utilities of virologic response, virologic resistance, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, treatment, interruption of treatment, death and seroconversion were collected in systematic reviews. Costs were collected in DATASUS, ABC da Saúde and scientific literature. RESULTS: Higher rate of virologic response and seroconversion was obtained with telbivudine, and also higher values of quality adjusted life years. However lamivudine is associated with lower costs and also lower cost-effectiveness values. The incremental cost-effectiveness ratios for telbivudine, when compared with lamivudine, were US$ 30,575 and US$ 40,457, respectively for HBeAg-positive and HBeAg-negative patients. CONCLUSION: In chronic hepatitis B lamivudine is a more cost-effective or even cost-saving strategy when compared with telbivudine.

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BACKGROUND: The susceptibility to adverse outcome from critical illness (occurrence of sepsis, septic shock, organ dysfunction/failure, and mortality) varies dramatically due to different degrees of inflammatory response. An over expression of tumor necrosis factor alpha (TNF-α) can lead to the progression of the inflammatory condition. OBJECTIVE: We assessed the relationship of the genotype distribution of -308G >A TNF-α polymorphism with regard to the development of sepsis, septic shock, higher organ dysfunction or mortality in critically ill patients. METHODS: Observational, hospital-based cohort study of 520 critically ill Caucasian patients from southern Brazil admitted to the general ICU of São Lucas Hospital, Porto Alegre, Brazil. Patients were monitored daily from the ICU admission day to hospital discharge or death, measuring SOFA score, sepsis, and septic shock occurrences. The -308G >A TNF-α SNP effect was analyzed in the entire patient group, in patients with sepsis (349/520), and in those who developed septic shock (248/520). RESULTS: The genotypic and allelic frequencies were -308GG = 0.72; -308GA = 0.27; -308AA = 0.01; -308G = 0.85; -308A = 0.15. No associations were found with sepsis, septic shock, organ dysfunction, and/or mortality rates among the TNF-α genotypes. Our results reveal that the -308G >A TNF-α SNP alone was not predictive of severe outcomes in critically ill patients. CONCLUSION: The principal novel input of this study was the larger sample size in an investigation with -308G > A TNF-α SNP. The presence of -308A allele is not associated with sepsis, septic shock, higher organ dysfunction or mortality in critically ill patients.

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BACKGROUND: Vulvovaginal candidiasis (VVC) is the second most common vaginal infection. HIV-infection is a risk factor for this infection. OBJECTIVE: To determine the frequency of VVC and to describe the main Candida species isolated and their susceptibility to antifungal drugs in HIV-infected patients, compared to HIV-uninfected women in Salvador, Brazil. METHODS: Cross-sectional study including a group of 64 HIV-infected women and 76 uninfected women, followed up at the AIDS reference center and at the Gynecological Clinic of Escola Bahiana de Medicina e Saúde Pública (Salvador, Bahia, Brazil). RESULTS: Frequency of Candida spp. was higher in HIV-infected women (29.7%) than in HIV-uninfected controls (14.5%) (p = 0.02). The odds ratio value for vulvovaginal candidiasis in HIV-infected patients was 2.6 (95% CI: 1.07 - 6.32 p = 0.03). Candida albicans was the most commonly isolated species in both HIV-infected (52.3%) and uninfected women (85.7%), followed by C. parapsolis in 17.6% and 14.3%, respectively. In HIV-infected women, C. glabrata, C. parapsilosis, and a coinfection of C. albicans and C. glabrata were also identified. There was no significant difference between Candida species isolated from the vaginal mucosa of women with VVC and colonization of the vaginal mucosa of HIV-infected and HIV-uninfected women. One C. glabrata isolate from an HIV-infected patient was resistant to fluconazole and other two isolates exhibited a dose-dependent susceptibility. CONCLUSION: Our results confirm a higher frequency of Candida spp. isolated from the vaginal mucosa of HIV-infected women and a broader spectrum of species involved. Only Candida glabrata isolates showed decreased susceptibility to fluconazole.

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Information about resistance profile of darunavir (DRV) is scarce in Brazil. Our objectives were to estimate the prevalence of DRV resistance mutations in patients failing protease inhibitors (PI) and to identify factors associated with having more DRV resistance mutations. All HIV-infected patients failing PI-based regimens with genotyping performed between 2007 and 2008 in a referral teaching center in São Paulo, Brazil, were included. DRV-specific resistance mutations listed by December 2008 IAS-USA panel update were considered. Two Poisson regression models were constructed to assess factors related to the presence of more DRV resistance mutations. A total of 171 HIV-infected patients with available genotyping were included. The number of patients with lopinavir, saquinavir, and amprenavir used in previous regimen were 130 (76%), 83 (49%), and 35 (20%), respectively. The prevalence of major DRV resistance mutations was 50V: 5%; 54M: 1%; 76V: 4%; 84V: 15%. For minor mutations, the rates were 11I: 3%; 32I: 7%; 33F: 23%; 47V: 6%; 54L: 6%; 74P: 3%; 89V: 6%. Only 11 (6%) of the genotypes had > 3 DRV resistance mutations. In the clinical model, time of HIV infection of > 10 years and use of amprenavir were independently associated with having more DRV resistance mutations. In the genotyping-based model, only total number of PI resistance mutations was associated with our outcome. In conclusion, the prevalence of DRV mutations was low. Time of HIV infection, use of amprenavir and total number of PI resistance mutations were associated with having more DRV mutations.

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BACKGROUND: Tuberculosis is the most common opportunistic infection among HIV-infected patients in Brazil. Brazil's national policy for HIV care recommends screening for latent tuberculosis (TB) and implementing isoniazid preventive therapy (IPT). OBJECTIVES: We compared physician adherence to TB screening and other prevention and care policies among HIV primary care clinics in Rio de Janeiro City. METHODS: Data on performance of CD4 counts, viral load testing, tuberculin skin testing (TST) and IPT were abstracted from patient charts at 29 HIV clinics in Rio de Janeiro as part of the TB/HIV in Rio (THRio) study. Data on use of pneumocystis jiroveci pneumonia (PCP) prophylaxis were also abstracted from a convenience sample of 150 patient charts at 10 HIV clinics. Comparisons were made between rates of adherence to TB guidelines and other HIV care guidelines. RESULTS: Among the subset of 150 patients with confirmed HIV infection in 2003, 96% had at least one reported CD4 counts result; 93% had at least one viral load result reported; and, PCP prophylaxis was prescribed for 97% of patients with CD4 counts < 200 cells/mm³ or when clinically indicated. In contrast, 67 patients (45%) had a TST performed (all eligible); and only 11% (17) of eligible patients started IPT. Among 12,027 THRio cohort participants between 2003 and 2005, the mean number of CD4 counts and viral load counts was 2.5 and 1.9, respectively, per patient per year. In contrast, 49% of 8,703 eligible patients in THRio had a TST ever performed and only 53% of eligible patients started IPT. CONCLUSION: Physicians are substantially more compliant with HIV monitoring and PCP prophylaxis than with TB prophylaxis guidelines. Efforts to improve TB control in HIV patients are badly needed.

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OBJECTIVES: To describe laboratory abnormalities among HIV-infected women and their infants with standard and increased lopinavir/ritonavir (LPV/r) dosing during the third trimester of pregnancy. METHODS: We evaluated data on pregnant women from NISDI cohorts (2002-2009) enrolled in Brazil, who received at least 28 days of LPV/r during the third pregnancy trimester and gave birth to singleton infants. RESULTS: 164 women received LPV/r standard dosing [(798/198 or 800/200 mg/day) (Group 1)] and 70 increased dosing [(> 800/200 mg/day) (Group 2)]. Group 1 was more likely to have advanced clinical disease and to use ARVs for treatment, and less likely to have CD4 counts > 500 cells/mm³. Mean plasma viral load was higher in Group 2. There were statistically significant, but not clinically meaningful, differences between groups in mean AST, ALT, cholesterol, and triglycerides. The proportion of women with Grade 3 or 4 adverse events was very low, with no statistically significant differences between groups in severe adverse events related to ALT, AST, total bilirubin, cholesterol, or triglycerides. There were statistically significant, but not clinically meaningful, differences between infant groups in ALT and creatinine. The proportion of infants with Grade 3 or 4 adverse events was very low, and there were no statistically significant differences in severe adverse events related to ALT, AST, BUN, or creatinine. CONCLUSION: The proportions of women and infants with severe laboratory adverse events were very low. Increased LPV/r dosing during the third trimester of pregnancy appears to be safe for HIV-infected women and their infants.

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BACKGROUND: Bacterial pneumonia is one of the main causes of morbidity and mortality in patients infected by the human immunodeficiency virus (HIV). The main objective of this study was to evaluate the effect of macrolide therapy in combination with a beta-lactam based empiric regimen for inpatients with community-acquired pneumonia and HIV. METHODS: This is a retrospective cohort study of hospitalized patients. Adult patients who had received treatment with ceftriaxone or ceftriaxone plus clarithromycin were included. RESULTS: 76 patients met the inclusion criteria. Among baseline characteristics analyzed, only respiratory rate showed significant difference: patients who had received clarithromycin were more likely to have a respiratory rate > 30/min than patients who received only ceftriaxone (64% versus 36%, p = 0.03). ICU admission was the only outcome that showed a significant difference, more frequent in the ceftriaxone plus clarithromycin group (45% versus 20%, p = 0.03). CONCLUSIONS: This study does not support the addition of a macrolide to a beta-lactam based regimen in HIV-infected patients. This is probably related to the patients' immunodeficiency status, which impairs the immunomodulatory properties of the macrolides.

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BACKGROUND: Patients with chronic liver disease have a higher risk of fulminant hepatitis when infected with hepatitis A virus, and vaccination of these patients against such infection is recommended. In Brazil, mainly in the South and Southeast regions, the epidemiology of hepatitis A (HA) has shifted from high to intermediate endemicity, which would have implication on policy of HA vaccination for these populations. OBJECTIVE: To verify the prevalence of HA immunity in adult patients with liver cirrhosis (LC), in Uberlândia MG, a city of Southeastern Brazil. METHODS: Between December 2005 and December 2006, 106 patients with LC were consecutively evaluated. In addition, 75 individuals without LC or alcoholism were evaluated (control group - CG). RESULTS: Total anti-HAV (ELISA methods) was positive in 104 (98.1%) patients with LC (82 men, 24 women; mean age, 53.3 ± 11.9 years) and in 74 (98.7%) individuals of the CG (55 men, 20 women; mean age, 47 ± 11.6 years), p > 0.05. CONCLUSIONS: For patients with chronic liver disease, in the geographic regions and age groups evaluated, routine vaccination against hepatitis A is not recommended. Moreover, the serum determination of total anti-HAV, used to assess immunity, is five times cheaper than vaccination against hepatitis A and, for this reason, should precede vaccination.

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A cross-sectional study was conducted in 151 (71.6%) of 211 male inmates of a regional Portuguese prison in order to establish the seroprevalence for viral hepatitis (HAV, HBV, HCV), human immunodeficiency virus (HIV), syphilis and herpes simplex virus (HSV-1 and HSV-2) and to analyze some psychosocial and criminal characteristics. Mean age was 34 years. Anti-HAV was positive in 69.5% (n = 105) and in 34.4% (n = 52) for anti-HCV. One (0.7%) person had HBsAg and 29 (19.2%) had laboratory markers of past HBV infection. Non-immune inmates for HBV were 40.4% (n = 61). Syphilis was diagnosed in 6.0% (n = 9). The rate of HIV infection was 6.6% (n = 10; all HIV-1). The seropositivity of HSV-2 was 19.9% (n = 30) and of HSV-1 was 82.1% (n = 124). Alcohol dependence was reported by 26.5% (n = 40). Excluding tobacco and prescription medication, 73.5% (n = 111) reported drug use in prison. The most commonly used drugs were: cannabis (100%; n = 111) followed by heroin (56.7%; n = 63). Anti-HCV rate was noteworthy. The HIV infection rate (6.6%) in this regional prison is at least 13 to 22 times greater than in general population. As the inmate return to the community increases the risk of disease exposure for the general population, early detection and counseling is urgently needed for prisoners.

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BK virus, a double-stranded DNA virus, is a member of the Polyomaviridae family which is known to infect humans. Clinical evidence of disease is mostly encountered in immunosuppressed individuals such as AIDS patients or those who undergo renal or bone marrow transplantation where complications associated with BKV infection manifest commonly as a polyomavirus nephropathy or hemorrhagic cystitis, respectively. Recent evidence suggests that in addition to the JC virus (the other member of the same family known to be strongly neurotropic and responsible for the progressive multifocal leukoencephalopathy), BK virus can infect and cause clinically relevant disease in the human central nervous system. In this mini-review, an analysis of the literature is made. A special focus is given to alert clinicians to the possibility of this association during the differential diagnosis of infections of the central nervous system in the immunocompromised host.

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We report a case of a 67 year-old-male patient admitted to the intensive care unit in the post-coronary bypass surgery period who presented cardiogenic shock, acute renal failure and three episodes of sepsis, the latter with pulmonary distress at the 30th post-operative day. The patient expired within five days in spite of treatment with vancomycin, imipenem, colistimethate and amphotericin B. At autopsy severe adenovirus pneumonia was found. Viral pulmonary infections following cardiovascular surgery are uncommon. We highlight the importance of etiological diagnosis to a correct treatment approach.

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Aureobasidium pullulans is a causal agent of phaeohyphomycosis, occasionally found in men and animals. As an agent of different opportunistic fungal processes, it may cause fungemia, systemic infections and abscesses in different viscera. This paper aims to report a case of a patient with infection of the lymphatic system by A. pullulans. A 23-year-old patient being treated for erythema nodosum leprosum presented a 60-day complaint of daily fever, hoarseness, odynophagia and weight loss. Laboratory tests showed pancytopenia with severe neutropenia, cervical adenomegaly and solid contrast uptake lesion in the oropharyngeal region. Due to neutropenia and sepsis the patient was initially treated with cefepime and vancomycin, but there was no clinical improvement. Lymph node puncture-aspiration showed yeast-form fungus identified as A. pullulans by sequencing ITS region. The patient was treated with amphotericin B deoxycholate, leading to complete recovery of bone marrow function and regression of adenomegaly and the oropharyngeal lesion.

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Staphylococcus lugdunensis is a rare cause of severe infections and clinical manifestations are similar to those related to S. aureus infection. We describe a hospital-acquired bacteremia due to methicillin-resistant Staphylococcus lugdunensis, misidentified as methicillin-resistant S. aureus. The oxacillin MIC was 16 µg/mL and the mecA gene and SCCmec type V were determined by PCR. Although treatment had been appropriated, the patient died after rapid progressive respiratory failure and another nosocomial sepsis. It is important not only to identify S. lugdunensis in view of its clinical course, but also to determine its susceptibility to oxacillin by detecting the mecA gene or its product.