No abstract

No abstract

The purpose of the present study was to validate the quantitative culture and cellularity of bronchoalveolar lavage (BAL) for the diagnosis of ventilator-associated pneumonia (VAP). A prospective validation test trial was carried out between 1992 and 1997 in a general adult intensive care unit of a teaching hospital. Thirty-seven patients on mechanical ventilation with suspected VAP who died at most three days after a BAL diagnostic procedure were submitted to a postmortem lung biopsy. BAL effluent was submitted to Gram staining, quantitative culture and cellularity count. Postmortem lung tissue quantitative culture and histopathological findings were considered to be the gold standard exams for VAP diagnosis. According to these criteria, 20 patients (54%) were diagnosed as having VAP and 17 (46%) as not having the condition. Quantitative culture of BAL effluent showed 90% sensitivity (18/20), 94.1% specificity (16/17), 94.7% positive predictive value and 88.8% negative predictive value. Fever and leukocytosis were useless for VAP diagnosis. Gram staining of BAL effluent was negative in 94.1% of the patients without VAP (16/17). Regarding the total cellularity of BAL, a cut-off point of 400,000 cells/ml showed a specificity of 94.1% (16/17), and a cut-off point of 50% of BAL neutrophils showed a sensitivity of 90% (19/20).In conclusion, BAL quantitative culture, Gram staining and cellularity might be useful in the diagnostic investigation of VAP. Correspondence

Fluids in which Mycobacterium tuberculosis are seldom found, such as pleural and cerebrospinal liquids, are good candidates to be studied using PCR techniques. We detail our experience with a PCR assay applied to pleural and cerebrospinal fluids using the primer MPB64. Seventy three specimens were analyzed: 30 pleural fluids (PF), 26 pleural biopsies (PB) and 17 cerebrospinal fluids (CSF). The gold standard for the diagnosis of tuberculous meningitis was the positive culture for M. tuberculosis in CSF. Tuberculous pleural effusion was diagnosed when cultures of PF and/or PB were positive for M. tuberculosis, or the PB histology showed granulomas. Our results, compared to the gold standards employed, showed a sensitivity of 70%, specificity of 88%, positive predictive value of 82% and negative predictive value of 80%. The high specificity of the MPB64 fragment while still retaining a good sensitivity makes it very well suited for pleural and cerebrospinal tuberculosis diagnosis. Key-words: Tuberculosis. Diagnosis. PCR technique. Central nervous system. Pleura.Resumo O Mycobacterium tuberculosis é raramente encontrado em fluidos como o líquido pleural e o cérebroespinhal, tornando estas localizações de difícil diagnóstico. Apresentamos nossa experiência com uma técnica de PCR aplicada a líquido pleural e cerebroespinhal com o uso do primer MPB64. Sessenta e três espécimes foram analisados: 30 líquidos pleurais (PF), 26 biópsias pleurais (PB) e 17 líquidos cerebroespinhais (CSF). O gold standard para o diagnóstico de meningite tuberculosa foi a cultura positiva para M. tuberculosis no CSF. Tuberculose pleural era diagnosticada quando culturas do PF e/ou PB eram positivas para M. tuberculosis, ou a histologia da PB mostrava granulomas. Nossos resultados, comparados aos gold standards empregados, mostram sensitividade de 70%, especificidade de 88%, valor preditivo positivo de 82% e valor preditivo negativo de 80%. A elevada especificidade e boa sensibilidade do fragmento MPB64 o transformam em um bom parâmetro para o diagnóstico de tuberculose pleural e do líquido cérebroespinhal. Palavras-chaves: Tuberculose. Diagnóstico. Técnica de PCR. Sistema nervoso central. Pleura.

No abstract

BackgroundMicrobiological characteristics of sepsis and antimicrobial resistance are well studied, although in State University of Campinas, no data has been published yet.MethodsThe main agents related to sepsis and antimicrobial resistance were analyzed. The blood culture records requested from 4,793 hospitalized patients were analyzed. The samples were processed using the Bact/Alert® system for agent identification and antimicrobial susceptibility.ResultsA total of 1,017 patients met the inclusion criteria for a sepsis diagnosis, with 2,309 samples tested (2.27 samples/patient). There were 489 positive samples (21% positive) isolated from 337 patients (33.13%), but more rigorous criteria excluding potential contaminants resulted in analysis being restricted to 266 patients (315 agents). The prevalent microorganisms were coagulase negative Staphylococcus (CNS) (15.87%), Escherichia coli (13.0%), Staphylococcus aureus (11.7%), Klebsiella pneumoniae (9.8%), Enterobacter sp (9.5%), Acinetobacter baumannii (9.2%), Pseudomonas aeruginosa (5.7%) and Candida sp (5.1%). Examining antimicrobial resistance in the agents revealed that 51% of the S. aureus isolates were methicillin-resistant S. aureus (MRSA) and 80% of the CNS isolates were oxacillin-resistant. For A. baumannii, the ideal profile drugs were ampicillin sulbactam and piperacillin/tazobactam, and for P. aeruginosa, they were piperacillin/tazobactam and ceftazidime. Enterobacteria showed on average 32.5% and 35.7% resistance to beta-lactams and ciprofloxacin, respectively. When all Gram-negative bacteria were considered, the resistance to beta-lactams rose to 40.5%, and the resistance to ciprofloxacin rose to 42.3%.ConclusionsEighty percent of the agents identified in blood cultures from patients with sepsis belonged to a group of eight different agents. For empirical treatment, carbapenems and vancomycin unfortunately still remain the best therapeutic choice, except for A. baumannii and P. aeruginosa, for which piperacillin/tazobactan is the best option.

No abstract

Vancomycin-resistant enterococci (VRE) are important pathogens involved in nosocomial infections. Colonization precedes infection and the number of colonized individuals is about 10 times higher than the number of infected patients. We examined VRE colonization in two intensive care units from October 2003 to June 2004. Perirectal swab specimens were obtained from all patients, starting on the 5th day after admission, and then weekly. A total of 249 swabs were obtained from 112 patients. Nine patients had VRE-positive swabs, giving a positive rate of 8.0%. The rate of patients colonized by V-R E. faecalis was 1.8% (n=2), 4.5% by V-R E. gallinarun (n=5) and 1.8% by V-R E. casseliflavus (n=2). No V-R E. faeciun was isolated. None of the patients that had been colonized by VRE were found to be infected by these pathogens. In summary, a low prevalence of colonization by VRE was found in our institution. Only a structured surveillance program, based on active searching, was able to detect this low number of cases.