We have correlated the in vitro results of testing the susceptibility of Cryptococcus neoformans to fluconazole with the clinical outcome after fluconazole maintenance therapy in patients with AIDS-associated cryptococcal disease. A total of 28 isolates of C. neoformans from 25 patients (24 AIDS patients) were tested. The MICs were determined by the broth microdilution technique by following the modified guidelines described in National Committee for Clinical Standards (NCCLS) document M27-A, e.g., use of yeast nitrogen base medium and a final inoculum of 10 4 CFU/ml. The fluconazole MIC at which 50% of isolates are inhibited (MIC 50 ) and MIC 90 , obtained spectrophotometrically after 48 h of incubation, were 4 and 16 g/ml, respectively. Of the 25 patients studied, 4 died of active cryptococcal disease and 2 died of other causes. Therapeutic failure was observed in five patients who were infected with isolates for which fluconazole MICs were >16 g/ml. Four of these patients had previously had oropharyngeal candidiasis (OPC); three had previously had episodes of cryptococcal infection, and all five treatment failure patients had high cryptococcal antigen titers in either serum or cerebrospinal fluid (titers, >1:4,000). Although 14 of the 18 patients who responded to fluconazole therapy had previously had OPC infections, they each had only a single episode of cryptococcal infection. It appears that the clinical outcome after fluconazole maintenance therapy may be better when the infecting C. neoformans strain is inhibited by lower concentrations of fluconazole for eradication (MICs, <16 g/ml) than when the patients are infected with strains that require higher fluconazole concentrations (MICs, >16 g/ml). These findings also suggest that the MICs determined by the modified NCCLS microdilution method can be potential predictors of the clinical response to fluconazole therapy and may aid in the identification of patients who will not respond to fluconazole therapy.Cryptococcosis is an infection caused by the ubiquitous fungus Cryptococcus neoformans, an encapsulated yeast-like fungus. The most frequent clinical presentation of the disease is meningoencephalitis (5, 6, 12, 18, 19; M. S. Saag, Editorial Response, Clin. Infect. Dis. 21:35-36, 1995); 75 to 90% of AIDS patients infected with C. neoformans will develop meningitis (5). Cryptococcosis in AIDS patients is seldom cured, and fluconazole is the drug of choice for the necessary lifelong suppressive (maintenance) therapy (17). Use of fluconazole for long-term suppressive therapy may be associated with the development of azole resistance in cryptococcal infections in AIDS patients (21).Methods for testing the antifungal susceptibility of C. neoformans could become important tools in the selection and monitoring of an appropriate antifungal drug for the treatment and prophylaxis of cryptococcal infections. Ghannoum et al. (9) developed a broth microdilution method for measuring the susceptibility of cryptococci to fluconazole, which is described as an alternative a...

Staphylococcus aureus is the most prevalent pathogen causing mastitis of dairy ruminants. This study was developed to ascertain the genotypes and genealogical relationship among strains isolated from milk of bovines with mastitis in Argentina. Molecular epidemiological analysis of S. aureus was performed on 112 isolates from 21 districts. Clonality was assessed by SmaI pulsed-field gel electrophoresis (PFGE) typing, automated EcoRI ribotyping and restriction enzyme analysis of plasmid (REAP) DNA profiles. A total of 22 band patterns distributed in four clusters were found by SmaI PFGE analysis. The similarity of clusters 2, 3 and 4 with cluster 1 was 0.73, 0.69 and 0.33, respectively, and 101 of 112 isolates belonged in cluster 1. PFGE band patterns from 42 isolates within cluster I were indistinguishable from each other (type A). The second largest group of isolates with indistinguishable PFGE band patterns was subtype A11, which was composed of 19 isolates. Automated ribotyping assigned the 112 isolates into 13 ribotypes. Among these, the most prevalent ribotypes I and VI were composed of 49 and 35 isolates respectively. Although there was certain correspondence between PFGE genotypes and ribotypes, further discrimination was achieved by combining both methods. REAP DNA profile analysis was useful to provide even further discrimination between isolates with identical PFGE genotype and ribotype. The most prevalent S. aureus strains A/I and A11/VI were widely distributed in the country and were not restricted to individual nearby locations. Prevalence of these two strains varied consecutively within a period of 8 years. Whether the shift in type prevalence was due to selection of a phenotypic trait remains undisclosed.

The effect of fluconazole prophylaxis on the vaginal flora of 323 human immunodeficiency virusinfected women was evaluated in a multicenter, randomized, double-blind, placebo-controlled trial. Women with CD4 cell counts of £300/mm 3 received either 200 mg of fluconazole per week or placebo. Vaginal surveillance cultures were performed every 3 months. After a follow-up of 29 months, Candida albicans was recovered from 53% of patients receiving fluconazole and 68% of patients assigned placebo. Fluconazole was associated with a 50% reduction in the odds of being colonized with C. albicans but with higher rates for non-albicans Candida species. Candida glabrata was recovered from 40 women assigned fluconazole and 29 assigned placebo (relative odds, 1.96; 95% confidence interval, 0.98 -3.94). Fluconazole had an early and persistent effect on the vaginal mycoflora, with the emergence of C. glabrata vaginal colonization within the first 6 months. The effect of fluconazole prophylaxis can be attributed to the reduction in vaginal C. albicans colonization; however, C. glabrata colonization rapidly supervened. Fungal infections are among the most common opportunisticPreviously, only alterations in the gastrointestinal microbial flora of hospitalized neutropenic patients receiving long-term complications in persons infected with HIV type 1 (HIV) [1,2]. The most frequently encountered fungal infections are suantifungal therapy have been described [14, 15]. We recently reported the results of a double-blind, placeboperficial (mucosal) infections, produced by opportunistic fungal pathogens belonging to the Candida species [1 -4].controlled trial of fluconazole, in a weekly dose of 200 mg, in preventing mucosal candidiasis in HIV-infected women with Fluconazole, a broad-spectrum systemic antifungal, is highly effective for the treatment of acute mucocutaneous candidiasis CD4 / cell counts of õ300/mm 3 [12]. The main findings of the study carried out by the Terry Beirn Community Programs in patients with AIDS, producing a more rapid clinical and mycologic response than observed with other azoles [5 -7]. In for Clinical Research on AIDS (CPCRA) were that weekly fluconazole was effective in preventing symptomatic oropharaddition, daily or intermittent doses of fluconazole have been shown to be effective in preventing mucosal candidiasis in yngeal and vaginal candidiasis over a 29-month follow-up. In addition, rates of clinical and in vitro fluconazole resistance AIDS patients [8 -13]. Nevertheless, use of fluconazole as both primary and secondary prophylaxis for fungal infections is conwere low and did not vary by treatment group. In addition, preliminary analysis of vaginal surveillance specimens coltroversial and generally not recommended because of cost, drug interactions, and risk of antifungal resistance in Candida spelected every 3 months revealed reduced rates of colonization with C. albicans and increased isolation of Candida species cies [13].Despite the high prevalence rates of mucosal candidiasis and other than Candida...

The in vitro activities of LY333328 were compared with those of vancomycin, teicoplanin, and quinupristin-dalfopristin (Synercid) against 219 strains of enterococci and staphylococci, including vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus. MICs and MBCs were determined by a microtiter dilution protocol. LY333328 demonstrated superior activity against vancomycin-resistant enterococci and was the only antibiotic which was bactericidal. Its potency was comparable or superior to those of other antibiotics tested against methicillin-resistant staphylococci.

Staphylococcus aureus is an important cause of bovine mastitis worldwide, and effective preventive or therapeutic modalities are lacking. Although most human S. aureus isolates produce capsular polysaccharides (CPs), few reports have described the prevalence of capsules on bovine isolates. This information is important for the rational design of a vaccine for the prevention of staphylococcal mastitis. We serotyped 195 S. aureus strains isolated between 1989 and 1997 from the milk of mastitic cows in Argentina. Only 14 (7.1%) of the strains were serotype 5, and all were recovered between 1989 and 1992. Thirteen serotype 8 strains were identified, and 12 of these were isolated between 1991 and 1994. The remaining 168 isolates were nonreactive (NR) with CP serotype 5 (CP5)- or CP8-specific antibodies. Hybridization studies performed with genomic DNA from eight NR strains revealed that only three of them carried the capsule genes. Pulsed-field gel electrophoresis (PFGE) performed with 127 of the 195 S. aureus isolates revealed that most (86%) strains belonged to one of four major PFGE groups. Although 8 of 14 CP5 isolates showed a common PFGE pattern (arbitrarily defined as A1), 31 other A1 isolates from the same time period (1989 to 1992) were not CP5 positive. In contrast, only nine PFGE type B3 isolates were recovered between 1990 and 1994, and eight of these were positive for CP8 (P < 0.0003). The results of this study underscore the variability in capsule expression by S. aureus strains isolated from different geographical regions and cast doubt on the roles of CP5 and CP8 in the pathogenesis and immunoprophylaxis of bovine mastitis in Argentina.