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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A series of 35 strains of Candida glabrata isolated from 29 subjects (5 AIDS patients and 24 HIV-seronegative individuals) were typed by electrophoretic karyotyping and tested for their susceptibilities to both fluconazole and itraconazole. Almost every individual harboured his/her own specific isolate (DNA type). Neither the source of isolation nor the patient's HIV status was associated with a given DNA type. Recurrences were generally due to the persistence of the same DNA type over time. Only 9% of the isolates showed reduced susceptibility to fluconazole (MIC > or = 8.0 microg/ml), while 43% of the isolates showed reduced susceptibility to itraconazole (MIC > or = 0.25 microg/ml) (P = 0.02). These data show that electrophoretic karyotyping is a useful technique for DNA typing of isolates of Candida glabrata. Care must be taken prior to initiation of antifungal therapy with either of these drugs.
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PMID:Electrophoretic karyotyping and triazole susceptibility of Candida glabrata clinical isolates. 1035 51

The adherence of fluconazole-resistant and fluconazole-susceptible isolates of Candida albicans to explanted rabbit esophageal mucosa was examined in vivo. Among six Candida albicans isolates collected from HIV-infected patients, three fluconazole-resistant (MIC > 64 microg/ml) isolates attached more avidly than three fluconazole-susceptible strains (MIC < or = 0.5 microg/ml) to esophageal mucosa (P < or = 0.05). When three strains each of six different Candida spp. were compared, the more inherently fluconazole-resistant isolates adhered more avidly in the following order: Candida glabrata>Candida krusei>Candida albicans fluconazole-sensitive>Candida tropicalis>Candida parapsilosis. Nonetheless, fluconazole-resistant Candida albicans demonstrated the greatest degree of adherence in comparison to all fluconazole-susceptible Candida albicans (P<0.001) and to all Candida spp. tested (P<0.001). Thus, the refractoriness of esophageal candidiasis in patients infected with fluconazole-resistant isolates may be related to both in vitro drug resistance and increased mucosal adherence.
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PMID:Increased adherence of fluconazole-resistant isolates of Candida species to explanted esophageal mucosa. 1035 58

Positive pneumococcal cultures of specimens from adult inpatients at San Francisco General Hospital (SFGH) during the period of 11 August 1994 through 31 December 1996 were identified retrospectively. Of the isolates recovered, 15.5% were not penicillin-susceptible (MIC, > or =.1 microg/mL). A case-control study was performed to evaluate risk factors for colonization or infection with penicillin-nonsusceptible Streptococcus pneumoniae (PNSP) and outcomes. Cases (n = 65) were adult inpatients with a positive culture for PNSP, and controls (n = 411) were adult inpatients with a positive culture for penicillin-susceptible pneumococci (PSSP) and no evidence of PNSP. Cases were less likely to have pneumococcal bacteremia (15.4% versus 39.4%; P<.001) and less likely to have pneumonia (50.8% versus 68.9%; P = .006). In a multiple logistic regression model, recent hospital admission and absence of bacteremia were independent predictors of penicillin-nonsusceptibility. Human immunodeficiency virus infection, mortality, and length of hospitalization were not significantly different among cases and controls. These data suggest that PNSP may be less virulent (cause less pulmonary infection) and/or less invasive (cause fewer bloodstream infections) than PSSP at SFGH.
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PMID:Penicillin-nonsusceptible Streptococcus pneumoniae at San Francisco General Hospital. 1053 Apr 51

In this report we compare the activity of two new antifungal agents, voriconazole (UK-109,496) and LY303366 with the activities of other antifungals including fluconazole, itraconazole, 5-fluorocytosine (5FC) and amphotericin B against 219 oral Candida spp. isolates from HIV-infected patients. We used the broth microdilution method following the guidelines of the NCCLS. The in-vitro activity of voriconazole (UK-109,496) (MIC(90) 0.12 mg/L) and LY303366 (CMI(90) 0.25 mg/L) against clinical isolates of Candida spp. was excellent and comparable with that of amphotericin B (MIC(90) 0.5 mg/L), and better than those of fluconazole (MIC(90) > or = 64 mg/L), itraconazole (MIC(90) 4 mg/L) and 5FC (MIC(90) 1 mg/L).
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PMID:In-vitro activity of voriconazole (UK-109,496), LY303366 and other antifungal agents against oral Candida spp. isolates from HIV-infected patients. 1055 89

The effects of prolonged itraconazole exposure on the susceptibility of Candida albicans isolates to itraconazole and fluconazole have not been well characterized. A recent placebo-controlled study of long-term itraconazole antifungal prophylaxis in persons with advanced human immunodeficiency virus infection afforded the opportunity to address this question. Mucosal Candida sp. isolates were obtained from subjects who developed oropharyngeal or esophageal candidiasis, and in vitro susceptibilities of the last isolate obtained at removal from the study as a prophylaxis failure were compared in itraconazole and placebo recipients. More subjects in the placebo group (74 of 146 [51%]) than in the itraconazole group (51 of 149 [34%]) developed mucosal candidiasis (P = 0.004). A total of 112 isolates were recovered from 56 of the 74 (76%) subjects with mucosal candidiasis assigned to the placebo group, compared to 97 isolates from 45 of the 51 (88%) subjects in the itraconazole group. C. albicans accounted for 98% of isolates in the placebo group and 89% of isolates in the itraconazole group. The itraconazole MIC at which 50% of the isolates tested were inhibited (MIC(50)) for last-episode isolates from the itraconazole group was 0.125 microg/ml compared to 0.015 microg/ml for the placebo group subjects, P = 0.0001. The MIC(50) of fluconazole for the last isolates from the itraconazole group was 1.5 microg/ml compared to 0.5 microg/ml for the placebo subjects (P = 0.005). A lower proportion of isolates recovered from subjects on itraconazole therapy were classified as susceptible to itraconazole (63%) compared to isolates from the placebo group (96%) (P = 0.001). Similarly, a lower proportion of C. albicans isolates from subjects on itraconazole therapy were susceptible to fluconazole (78%) compared to isolates from the placebo group (96%) (P = 0.01). Also, the proportion of isolates that were not fully susceptible to itraconazole or fluconazole was greater in patients assigned to the itraconazole group than the placebo group (itraconazole susceptibility, 37 and 4%, respectively (P = 0.001); fluconazole susceptibility, 23 and 4%, respectively (P = 0.01). In conclusion, long-term itraconazole prophylaxis in patients with AIDS is associated with reduction in susceptibility to itraconazole and cross-resistance to fluconazole.
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PMID:Does long-term itraconazole prophylaxis result in in vitro azole resistance in mucosal Candida albicans isolates from persons with advanced human immunodeficiency virus infection? The National Institute of Allergy and Infectious Diseases Mycoses study group. 1081 13

Fungal opportunistic infections, and in particular those caused by the various Candida species, have gained considerable significance as a cause of morbidity and, often, mortality. The newly described species Candida dubliniensis phenotypically resembles Candida albicans so closely that it is easily misidentified as such. The present study was designed to determine the frequency at which this new species is not recognized in the clinical laboratory, to determine the patient populations with which C. dubliniensis is associated, to determine colonization versus infection frequency, and to assess fluconazole resistance. Over a 2-year period, 1,251 isolates that were initially identified as C. albicans by a hospital clinical laboratory were reevaluated for C. dubliniensis by inability to grow at 45 degrees C, colony color on CHROMagar Candida medium, coaggregation assay with Fusobacterium nucleatum, and sugar assimilation profiles (API 20C AUX yeast identification system). A total of 15 (1.2%) isolates from 12 patients were identified as C. dubliniensis. Ten of the patients were found to be immunocompromised (these included patients with human immunodeficiency virus infection or AIDS, cancer patients receiving chemotherapy, and patients awaiting transplantation). Thirteen isolates were highly susceptible to fluconazole (MIC, <0.5 microgram/ml). Three isolates from one patient, genotypically confirmed as the same strain, showed variable susceptibility to fluconazole. The first isolate was susceptible, whereas the other two isolates were dose-dependent susceptible (MIC, 16.0 microgram/ml). These data confirm the close association of C. dubliniensis with immunocompromised states and that increased fluconazole MICs may develop in vivo. This study emphasizes the importance of screening germ-tube-positive yeasts for the inability to grow at 45 degrees C followed by confirmatory tests in order to properly identify this species.
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PMID:Retrospective identification and characterization of Candida dubliniensis isolates among Candida albicans clinical laboratory isolates from human immunodeficiency virus (HIV)-infected and non-HIV-infected individuals. 1083 22

We studied the possible differences in the pattern of susceptibility to fluconazole and itraconazole in 393 isolates of Candida spp. from the oral cavity of HIV-positive patients and 102 isolates from HIV-negative patients with candidemia or candiduria. We used the broth microdilution method according to the NCCLS guidelines. We observed a decrease in the susceptibility to fluconazole in the group of HIV-positive patients in comparison to those who were HIV negative, especially in Candida albicans (MIC(90) 32 mg/l vs. 1 mg/l and Candida glabrata (MIC(90) 64 mg/l vs. 16 mg/l). Furthermore, we did not find any resistant strains in the HIV-negative group. For itraconazole, the MIC(90) was two dilutions greater in the HIV-positive patients, except for C. albicans, which had a much higher MIC(90) (4 mg/l vs. 0.12 mg/.). Therefore, the decrease in the susceptibility of Candida spp. in the HIV-positive patients must be taken into account when establishing a specific antifungal therapy.
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PMID:[Susceptibility to fluconazole and itraconazole in isolates of Candida spp. from HIV-positive and HIV-negative patients]. 1085 26

We studied the possible differences in the pattern of susceptibility to fluconazole and itraconazole in 393 isolates of Candida spp. from the oral cavity of HIV-positive patients and 102 isolates from HIV-negative patients with candidemia or candiduria. We used the broth microdilution method according to the NCCLS guidelines. We observed a decrease in the susceptibility to fluconazole in the group of HIV-positive patients in comparison to those who were HIV negative, especially in Candida albicans (MIC(90) 32 mg/l vs. 1 mg/l and Candida glabrata (MIC(90) 64 mg/l vs. 16 mg/l). Furthermore, we did not find any resistant strains in the HIV-negative group. For itraconazole, the MIC(90) was two dilutions greater in the HIV-positive patients, except for C. albicans, which had a much higher MIC(90) (4 mg/l vs. 0.12 mg/.). Therefore, the decrease in the susceptibility of Candida spp. in the HIV-positive patients must be taken into account when establishing a specific antifungal therapy.
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PMID:[Susceptibility to fluconazole and itraconazole in isolates of Candida spp. from HIV-positive and HIV-negative patients] 1087 39

A point prevalence study to document oral yeast carriage was undertaken. Risk factors for the development of oropharyngeal colonization or infection by fluconazole-resistant Candida strains in HIV-infected patients were investigated with a case-control design. Cases included all patients with fluconazole-resistant strains (MIC> or =64 microg/ml), and controls were those with susceptible (MIC< or =8 microg/ml) or susceptible-dependent-upon-dose (MIC 16-32 microg/ml) strains. One hundred sixty-eight Candida strains were isolated from 153 (88%) patients, 28 (16%) of whom had oropharyngeal candidiasis. Overall, 19 (12%) of the patients harbored at least one resistant organism (MIC > or = 64 microg/ml). Among patients with resistant strains, tuberculosis (P<0.001), esophageal candidiasis (P = 0.001), clinical thrush (P<0.001), and a CD4 + cell count < 200/mm3 (P = 0.03) were more frequent. These patients had also been treated more commonly with antituberculous drugs (adjusted odds ratio [OR] 6.13; 95% confidence interval [CI] 2.11-17.80), ciprofloxacin (OR 6.0; 95% CI 1.23-29.26), fluconazole (OR 4.59; 95% CI 1.55-13.52), and steroids (OR 4.13; 95% CI 1.11-15.39). Multivariate analysis showed that the determinants for fluconazole resistance were therapy with antituberculous drugs (OR 3.61; 95% CI 1.08-12.07; P=0.03) and one of the following: previous tuberculosis (OR 3.53; 95% CI 1.08-14.57; P=0.03) or fluconazole exposure (OR 3.41; 95% CI 1.10-10.54). Findings from this study indicate that treatment with antituberculous drugs, previous tuberculosis, and fluconazole exposure are the strongest determinants for development of oropharyngeal colonization or infection by fluconazole-resistant Candida strains in HIV-infected patients.
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PMID:Determinants for the development of oropharyngeal colonization or infection by fluconazole-resistant Candida strains in HIV-infected patients. 1101 21

The molecular mechanisms of azole resistance in Candida albicans include alterations in the target enzyme (lanosterol 14-demethylase) and overexpression of efflux transporters that decrease the intracellular concentration of the drug. Although the rate of azole resistance in systemic isolates of C. albicans remains very low, resistance to fluconazole appears as an important issue in the management of oropharyngeal candidiasis (OPC) in patients with AIDS. In order to establish the prevalence of resistance to azole antifungal agents in this setting, we investigated the molecular mechanisms of resistance to azoles in highly resistant C. albicans isolates (fluconazole MIC 64 mg/l) from HIV-infected patients with OPC. Antifungal susceptibility testing of serial C. albicans isolates was performed by NCCLS methodology. Strain identity was investigated by DNA-typing techniques. Overexpression of genes encoding lanosterol 14-demethylase (erg11) and efflux transporters (mdr1 and cdr) implicated in the development of resistance was monitored in matched sets of susceptible and resistant isolates. In addition, erg11 genes were PCR-amplified and their nucleotide sequences determined in order to detect point mutations. A combination of different mechanisms of resistance contributed to the development of resistance to fluconazole. The multifactorial character of the azole resistance in C. albicans makes necessary the development of approaches to overcome the problem. Accordingly, new triazoles have been developed; new classes of antifungals are being investigated; and combinations with inhibitors of efflux transporters are being studied.
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PMID:[Azole resistance in Candida albicans]. 1108 83


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