Resumo em Inglês:

The objective of this study was to characterize patterns of the Brazilian endemic clone of methicillin-resistant Staphylococcus aureus (MRSA) from hospitals throughout Brazil. We studied 83 MRSA strains isolated from patients hospitalized in 27 public and private hospitals in 19 cities located in 14 Brazilian states from September, 1995, to June, 1997. The MRSA strains were typed using antibiograms, bacteriophage typing and pulsed field gel electrophoresis (PFGE). The analysis of genomic DNA by PFGE showed that 65 isolates presented the same PFGE pattern. This pattern was present in all of the hospitals studied indicating the presence of an endemic MRSA clone widely disseminated throughout Brazilian hospitals (BEC). All isolates belonging to the BEC proved to be resistant to ciprofloxacin, erythromycin, lincomycin, trimethoprim-sulphamethoxazole, and tetracycline. Variable susceptibility to these drugs was found only in isolates belonging to clones other than the BEC. The results show that, among MRSA, the BEC is common in Brazil. The best method for mapping changes in the frequency of this clone among MRSA is pulsed field gel electrophoresis. Use of molecular mapping is an important tool for monitoring the spread of potentially dangerous microbes.

Resumo em Inglês:

The new oxazolidinone linezolid and other antimicrobial agents used to treat Gram-positive infections were tested against 1,585 Gram-positive cocci; 1,260 staphylococci and enterococci isolates from patients hospitalized in Brazilian hospitals, and 325 S. pneumoniae isolates for patients with community acquired infections. Susceptibility testing was performed using broth microdilution according to NCCLS procedures. Linezolid was the most active compound and the only drug that inhibited 100% of the isolates at the susceptible breakpoint (< 4 mg/mL). Resistance to vancomycin was very rare (99.9% susceptibility), and both quinupristin/dalfopristin and gatifloxacin were active against approximately 90% of the strains evaluated. All other compounds inhibited less than 65% of the isolates. The excellent in vitro Gram-positive activity by linezolid, in this study, indicate that this compound may represent an important therapeutic option for the treatment of infections caused by these pathogens in Brazil.

Resumo em Inglês:

We evaluated samples of peripheral blood mononuclear (PBMC) cells from 46 AIDS patients, before starting therapy with HIV-1 reverse transcriptase inhibitors (RTI), and after 6 months of drug use. PBMC were stored and tested by a Line Probe Assay (LiPA), in order to assess the frequency of RT mutations in this population. Six patients were taking AZT before initial blood collection (1 to 16 weeks of drug use) and 40 patients had no prior therapy. After baseline evaluation, 19 patients received AZT, 23 AZT plus DDI, 3 started AZT only with DDI added after 3 months, and 3 received a combination of AZT plus 3TC. Detection of at least one mutation was found in 33% (15/46) of patients at baseline, and 83% (38/46) had at least 1 mutation after 6 months of therapy. In the majority of cases, samples presented with the wild type and variants of HIV, simultaneously. Patients receiving monotherapy had a higher frequency of mutations (L41 and F214, Y215) than did patients receiving double-drug therapy (19 vs. 10). No specific mutation associated with DDI was identified in 26 patients so treated. Despite the finding of a mean increase in CD4 count and a mild decrease in viral load, patients tended to have an inverse correlation between the CD4 variation and number of mutations detected after 6 months, suggesting potential loss of drug efficacy in the presence of these genotypic changes.

Resumo em Inglês:

Two different procedures for inoculation of HSV on corneas of BALB/c mice were evaluated. The first was by the use of HSV suspensions directly on the corneas and the other was after corneal scarification. Animals by this later method presented greater morbidity and mortality than those of first group, suggesting that inoculation of HSV without scarification of the cornea should be the method of choice for the study of HSV ophthalmic infection. This model showed also be an efficient experimental system to testing antiviral drugs.

Resumo em Inglês:

Lipid and acute-phase protein alterations have been described in various infection diseases, and they have been recorded during the early stages of HIV infection. Lipid and acute-phase protein profiles also have been correlated with cellular immunological abnormalities. To document these correlations during HIV infection, we studied 75 HIV-infected patients and 26 HIV-negative controls. Patients were classified according to the criteria proposed by the Walter Reed Army Institute: as WR-1 (CD4 lymphocytes, 1154 ± 268/mm³), WR-2 (CD4, 793 ± 348/mm³) and WR3/4 (CD4, 287±75 mm³). Triglycerides, total cholesterol and HDL-cholesterol concentrations were measured by enzymatic methods. Immunoglobulins (IgA and IgG) and acute-phase proteins (haptoglobin, a1-acid glycoprotein, C-reactive protein and transferrin) were determined by immunonephelometry. Haptoglobin levels were significantly increased in HIV-positive patients and correlated with the progression of HIV-infection (control<WR1<WR2<WR3/4). WR-2 and WR-3/4 patients had lower total cholesterol, HDL-cholesterol, and albumin concentrations, however, a1-acid glycoprotein and IgA levels were higher, when compared to HIV-negative controls. Elevated triglyceride levels (1.51±0.75 mmol/L) were found only in WR3/4 patients, when compared to the control individuals (1.05±0.04 mmol/L). No differences were found in transferrin and C-reactive protein concentrations among the studied groups. CD4+ lymphocyte counts were inversely correlated with triglycerides, IgA, a1-acid glycoprotein and haptoglobin, and they were positively correlated with albumin, total cholesterol and HDL-cholesterol. Multiple linear regression analysis showed that increased haptoglobin and IgA levels were the best predictive variables of a decreasing CD4+ lymphocyte count. In conclusion, our data showed that: 1) a decrease in total cholesterol, HDL-cholesterol and albumin levels occurred earlier than hypertriglyceridemia in the course of HIV infection; 2) increased levels of haptoglobin occurred earlier than that of a1-acid glycoprotein and IgA; 3) haptoglobin and IgA were the best predictive variables of a decreasing CD4+ lymphocyte count. Decreases in HDL-cholesterol and albumin levels with increases in haptoglobin, a1-acid glycoprotein, IgA, and triglycerides levels are indications of disease progression in HIV-infected patients.

Resumo em Inglês:

BACKGROUND: Pathogen frequency and resistance patterns may vary significantly from country to country and also in different hospitals within a country. Thus, regional surveillance programs are essential to guide empirical therapy and infection control measures. METHODS: Rank order of occurrence and antimicrobial susceptibility of pathogenic species causing bloodstream infections (BSI), lower respiratory tract infections (LRTI), wound or skin and soft tissue infections (WSSTI), and urinary tract infections (UTI) in hospitalized patients were determined by collecting consecutive isolates over a specified period of time, as part of the SENTRY Antimicrobial Resistance Surveillance Program (SENTRY). All isolates were tested by reference broth microdilution. RESULTS AND CONCLUSIONS: A total of 3,728 bacterial strains were obtained from January, 1997, to December, 1999, from 12 Brazilian hospitals located in 4 states. The largest number of isolates were obtained from patients with BSI (2,008), followed by LRTI (822 cases), UTI (468 cases), and WSSTI (430 cases). Staphylococcus aureus was the most frequently isolated pathogen in general (22.8% - 852 isolates), followed by E. coli (13.8% - 516 cases) and Pseudomonas aeruginosa (13.3% - 496 cases). Staphylococcus aureus was also the most common species isolated from BSI (23.6%) and WSSTI (45.8%), and P. aeruginosa was the most frequent species isolated from patients with LRTI (29.4%). The main bacterial resistance problems found in this study were: imipenem resistance among P. aeruginosa (69.8% susceptibility) and Acinetobacter spp. (88.1% susceptibility); ESBL production among K. pneumoniae (48.4%) and E. coli (8.9%); resistance to third generation cephalosporins among Enterobacter spp. (68.1% susceptible to ceftazidime) and oxacillin resistance among S. aureus (34.0%) and coagulase negative staphylococci (80.1%). Only the carbapenems (88.1% to 89.3% susceptibility) showed reasonable activity against the Acinetobacter spp. isolates evaluated.

Resumo em Inglês:

In order to develop good polices regarding public health measures and vaccine use to prevent rotavirus induced gastroenteritis, the epidemiology of the illness in various regions of Brazil is necessary. Accordingly, this study was to detect the frequency and types of rotavirus in one city in a tropical part of Brazil. This is an epidemiological survey of pediatric gastroenteritis caused by rotavirus conducted in Juiz de Fora, Minas Gerais State, Brazil. We analyzed 656 in-patient (190) and out-patient (466) stool samples from children ages 0 to 5 years during 1998. Rotavirus detection was performed using polyacrylamide gel electrophoresis (PAGE). Rotavirus was isolated from 62/190 stool samples (32.6%) from hospitalized children and 16/466 (3.4%) from out-patients. The overall rotavirus frequency in this population was 11.9%. The highest rotavirus detection was found in hospitalized children ages 6 to 24 months. Rotaviruses were detected from March to September, with a peak incidence in June (33.3%), the coldest and driest month in the region. Electrophoretic analysis identified 10 different profiles, all long and compatible with group A rotavirus, termed L A through LJ. The L B and L D profiles circulated throughout most of the study period. However, in June, when the highest detection rate occurred, the vast majority (92.5%) of the positive samples displayed the L B profile, thus suggesting an outbreak caused by this rotavirus profile. Rotavirus induced gastroenteritis is common in one tropical region of Brazil, it is an important cause of diarrhea in hospitalized children ages 6 to 24 months, it is most common during dry, cold months of the year, and it may occur in electrophoretype restricted epidemics. Such analyses throughout Brazil will assist in developing sound guidelines regarding its prevention.

Resumo em Inglês:

Immunotherapy has been proposed as a method to treat mucosal leishmaniasis for many years, but the approach has been hampered by poor definition and variability of antigens used, and results have been inconclusive. We report here a case of antimonial-refractory mucosal leishmaniasis in a 45 year old male who was treated with three single injections (one per month) with a cocktail of four Leishmania recombinant antigens selected after documented hypo-responsiveness of the patient to these antigens, plus 50mg of GM-CSF as vaccine adjuvant. Three months after treatment, all lesions had resolved completely and the patient remains without relapse after two years. Side effects of the treatment included only moderate erythema and induration at the injection site after the second and third injections. We conclude that carefully selected microbial antigens and cytokine adjuvant can be successful as immunotherapy for patients with antimonial-refractory mucosal leishmaniasis.