Evaluation of Fusarium solani hyphae and conidia susceptibility to amphotericin B and itraconazole: study of a clinical case.

Fusarium species are hyaline moulds belonging to the hyalohyphomycosis group that are usually found in the soil and plants. This organism has emerged as a cause of disseminated invasive disease. The correlation between in vitro value and clinical efficacy is low and many patients remain unresponsive to treatment despite in vitro susceptibility. We determined growth control for Fusarium solani using the BioCell-Tracer system that measures the growth rate of a single fungal hypha, and the effect of different concentrations of amphotericin B and itraconazole. The MIC for these two drugs was also determined by a broth microdilution technique, using RPMI 1640. Different MICs for amphotericin B were obtained by the two different methods. This paper describes a case of infection due to Fusarium solani in an allogeneic bone marrow transplanted patient, the microbiological diagnostic, antifungal susceptibility tests for conidia and hypha and clinical correlation.

Diagnostic investigation of ventilator-associated pneumonia using bronchoalveolar lavage: comparative study with a postmortem lung biopsy

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 percent) were diagnosed as having VAP and 17 (46 percent) as not having the condition. Quantitative culture of BAL effluent showed 90 percent sensitivity (18/20), 94.1 percent specificity (16/17), 94.7 percent positive predictive value and 88.8 percent negative predictive value. Fever and leukocytosis were useless for VAP diagnosis. Gram staining of BAL effluent was negative in 94.1 percent 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 percent (16/17), and a cut-off point of 50 percent of BAL neutrophils showed a sensitivity of 90 percent (19/20). In conclusion, BAL quantitative culture, Gram staining and cellularity might be useful in the diagnostic investigation of VAP

Diagnostic investigation of ventilator-associated pneumonia using bronchoalveolar lavage: comparative study with a postmortem lung biopsy.

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.

Reduction in colonization and nosocomial infection by multiresistant bacteria in a neonatal unit after institution of educational measures and restriction in the use of cephalosporins.

INTRODUCTION: Previous administration of third-generation cephalosporins predisposes to colonization and infections by multiresistant Enterobacter sp. The emergence of multiresistant bacteria infections in a neonatal unit during 1995, especially Enterobacter cloacae, stimulated this study. OBJECTIVE: To evaluate the efficacy of measures to control colonization and nosocomial infection by multiresistant bacteria in a neonatal unit. SETTING: A tertiary care university hospital. PATIENTS AND METHODS: This study was conducted from October 1995 through December 1999 in 4 phases: a cross-sectional study, a longitudinal study with intervention measures, monthly cross-sectional studies, and determination of nosocomial infections caused by multiresistant bacteria (oxacillin-resistant Staphylococcus aureus and gram-negative bacteria resistant to either aminoglycosides or third-generation cephalosporins). Specimens for surveillance culture were obtained through umbilical and rectal swabs, and tracheal aspirates from intubated babies. The intervention measures were as follows: (1) appropriated training of the whole health care team, emphasizing measures to reduce cross-colonization, and the importance of rational usage of antibiotics and (2) suppression of usage of third-generation cephalosporins. Risk factors were analyzed through univariate and multivariate logistic regression. RESULTS: In the first phase, 32% (10/31) of the patients were colonized by multiresistant bacteria (29% by multiresistant E cloacae ). In the second phase, 342 patients were evaluated; 33% of them were colonized by E cloacae, and a multiresistant strain was isolated in 10.8% (37/342) of the babies. A logistic regression model indicated parenteral nutrition and antibiotic usage as risk factors for colonization by multiresistant E cloacae. In the third phase, for 6 months, only 2 patients were colonized by multiresistant E cloacae. In the fourth phase, the analysis of bacterial resistance profile indicated a reduction of nosocomial infections due to multiresistant bacteria from 18 cases in 1995 to 2 cases per year until 1999. CONCLUSION: These results have shown that the measures adopted were effective.

Nasal MRSA colonization of AIDS Patients cared for in a Brazilian university hospital.

Weekly culture surveillance was conducted over a 2-year period to determine the incidence of methicillin-resistant Staphylococcus aureus nasal colonization among acquired immunodeficiency syndrome patients cared for in a day-care unit and in an infectious diseases unit. Analysis of genomic DNA profiles showed a predominant pattern in both units.

Nested-PCR using MPB64 fragment improves the diagnosis of pleural and meningeal tuberculosis.

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.

Enterobacter cloacae sepsis outbreak in a newborn unit caused by contaminated total parenteral nutrition solution.

OBJECTIVE: The study aimed to investigate an outbreak caused by Enterobacter cloacae in a neonate intensive care unit. DESIGN: A descriptive study of an outbreak of sepsis in high-risk neonates was used. SETTING: The study was set in a tertiary care university teaching hospital. PATIENTS: The patients were 11 neonates infected with Enterobacter cloacae whose symptoms and signs of sepsis developed during a 16-hour period. All but one neonate received parenteral nutrition. Isolates from blood cultures, in-use parenteral nutrition solutions, and control aliquots of parenteral nutrition solution were typed by pulsed-field gel electrophoresis. RESULTS: Enterobacter cloacae was found in the refrigerated aliquots of parenteral nutrition solution, in blood cultures from infected newborns, and from in-use parenteral nutrition solutions. All these strains of Enterobacter cloacae had the same antibiotic susceptibility pattern and the same genomic DNA profile. The strain isolated from the one patient who did not receive parenteral nutrition presented a different susceptibility profile and genotype. CONCLUSION: The source of the nosocomial sepsis was the parenteral nutrition solution in 10 neonates. This contamination apparently occurred during preparation of the parenteral solution.

Molecular epidemiology of a nosocomial outbreak due to Enterobacter cloacae and Enterobacter agglomerans in Campinas, São Paulo, Brazil.

A total of 73 isolates (57 Enterobacter cloacae and 16 Enterobacter agglomerans), recovered during an outbreak of bacteremia in the Campinas area, São Paulo, Brazil, were studied. Of these isolates, 61 were from parenteral nutrition solutions, 9 from blood cultures, 2 from a sealed bottle of parenteral nutrition solution, and one was of unknown origin. Of the 57 E. cloacae isolates, 54 were biotype 26, two were biotype 66 and one was non-typable. Of 39 E. cloacae isolates submitted to ribotyping, 87.2% showed the same banding pattern after cleavage with EcoRI and BamHI. No important differences were observed in the antimicrobial susceptibility patterns among E. cloacae isolates exhibiting the same biotype, serotype and ribotype. All E. agglomerans isolates, irrespective of their origin, showed same patterns when cleaved with EcoRI and BamHI. The results of this investigation suggest an intrinsic contamination of parenteral nutrition solutions and incriminate these products as a vehicle of infection in this outbreak.

Relative frequency of nosocomial microorganisms at UNICAMP University Hospital from 1987 to 1994.

The frequency of microorganisms identified in nosocomial infections at Unicamp University Hospital from 1987 to 1994 was analysed. The most common microorganism was S. aureus (20.9%), which was found in surgical wound, bloodstream and arterial-venous infections. In urinary tract infections (UTI), gram-negative rods (56.5%) and yeasts (9%) predominated. A. baumannii isolates were observed to have increased in the last three years. There was a gradual increase in the frequency of coagulase-negative staphylococci and A. baumannii in bloodstream infections but there wasn't any change in Candida sp.

Listeriosis and AIDS: case report and literature review.

Listeriosis is a not uncommon infection in humans, usually associated with immunodeficient states and with newborns. However, relatively few cases have been reported in HIV-infected patients. This scarcity of reported cases has aroused interest in the association of listeriosis and AIDS. In this paper we present a case of meningitis and septicemia caused by Listeria monocytogenes in a female patient with AIDS. A review of recent medical literature indicates that association of listeriosis and AIDS may be more common than it seems. Recent research in host-parasite interaction in listerial infection suggests an important role for tumor necrosis factor (TNF) and for integralin, a bacterial protein, in modulating listerial disease in AIDS patients. Inadequate diagnosis may be in part responsible for the scarcity of reports.

Semiquantitative culture in diagnosing venous catheter-related sepsis.

Since Aubaniac (1) described the puncture of the subclavian vein in 1952, and specially after the standardization of parenteral nutrition by Dudrick et al. (11) in 1968, much has been published about complications caused by percutaneous central venous catheterization. Among the various complications provoked by this procedure, a very important one is "primary sepsis" or "catheter-related sepsis", both because of its frequency and because of the morbidity and mortality it causes (18,19). It is, however, difficult to diagnose this complication. The main difficulty lies in differentiating catheters that are really causing sepsis from those that, though showing "positive culture" do not cause bacteremia and are not responsible for the occasional signs of infection that a patient may show (6,7). This difficulty in diagnosing has led to the recommendation that all catheters suspected of causing sepsis be systematically removed. This procedure has the effect of exposing patients in serious condition and with limited venous access to the risks of new punctures. Usually these risks are unnecessary, since 75 to 90% of the catheters removed for this reason are not the real source of infection (3, 17, 19, 21, 22). In 1977, Maki et al. (18) proposed a semiquantitative catheter tip culture that showed considerable correlation with positive hemoculture for the same microorganisms; that is, capable of identifying which "positive catheters" were really causing sepsis. Subsequent research confirmed these results, showing that the semiquantitative catheter tip culture had specificity and sensibility over 80% (10, 15).(ABSTRACT TRUNCATED AT 250 WORDS)