RESUMO
Chromoblastomycosis is a chronic subcutaneous disease caused by human contact with melanized fungi occurring mainly in tropical and subtropical zones worldwide. This study assessed 12 patients with chromoblastomycosis from Rondônia, Brazil, Amazon region. In sum, 83.3% were men, 41.6% were from Monte Negro city, median age was 52.9 years, and median time to disease progression was 12.2 years. Lesions were located on the lower limbs (75%), and verruciform was prevalent form (66.6%). After 3 years of treatment with itraconazole, two patients were considered cured. The etiological agents were identified by the molecular sequence of the ribosomal internal transcribed spacer ITS1, 5.8S, and ITS2 region and ß-tubulin genes. Eight strains were identified as Fonsecaea pedrosoi, two were F. nubica, and two were Rhinocladiella similis. The antifungal activity of five drugs was evaluated, and the most active drug was terbinafine (range minimal inhibitory concentration [MIC] 0.015-0.12 µg/ml), itraconazole (range MIC 0.03-0.5 µg/ml) and voriconazole (range MIC 0.06-0.5 µg/ml). The highest MIC was 5-fluorocytosine (range MIC 2-32 µg/ml), and amphotericin B (range MIC 0.25-2 µg/ml). In conclusion, the present study expanded the epidemiological disease database and described for the first time F. nubica and R. similis as chromoblastomycosis agents in the Brazilian Amazon region. Our results confirmed the importance of using molecular methods to identify the melanized fungi and stimulate the recognition of the disease in other places where no cases have been reported.
Assuntos
Antifúngicos/farmacologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Cromoblastomicose/epidemiologia , Fungos Mitospóricos/genética , Adulto , Idoso , Antifúngicos/uso terapêutico , Brasil/epidemiologia , Cromoblastomicose/diagnóstico , Cromoblastomicose/tratamento farmacológico , Cromoblastomicose/microbiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Feminino , Humanos , Itraconazol/farmacologia , Itraconazol/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Fungos Mitospóricos/efeitos dos fármacos , Filogenia , Análise de Sequência de DNARESUMO
Fusarium species have emerged as responsible for a broad spectrum of infections, including superficial, locally invasive and disseminated ones, especially in the hospital environment. Since there are few reports of invasive and disseminated fusariosis in children, the aim of this study was to report four cases of nosocomial infection caused by this microorganism in children with cancer hospitalized in a public children's hospital located in Brazil. Two of these patients were female and two were male. All patients presented febrile neutropenia, while three patients had acute lymphocytic leukemia and one patient had Wilms' tumor as underlying disease. In two cases, fungi were isolated from blood and identified as Fusarium oxysporum species complex after phenotypic and genotypic studies, while in two other cases fungi were isolated from skin biopsies and identified as Fusarium solani species complex. One patient died 12 days after the onset of cutaneous lesions. All isolates, after susceptibility testing, presented high levels of minimum inhibitory concentration for itraconazole, voriconazole and amphotericin B. Considering the emergence of filamentous fungi as etiologic agents of nosocomial infections, health professionals should be aware of the problems these infections, especially fungal ones, may cause to debilitated patients.
Assuntos
Infecção Hospitalar/diagnóstico , Infecção Hospitalar/patologia , Fusariose/diagnóstico , Fusariose/patologia , Fusarium/isolamento & purificação , Leucemia Linfoide/complicações , Tumor de Wilms/complicações , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Brasil , Criança , Infecção Hospitalar/tratamento farmacológico , Feminino , Fusariose/tratamento farmacológico , Fusarium/classificação , Fusarium/efeitos dos fármacos , Fusarium/genética , Genótipo , Hospitais Pediátricos , Humanos , Masculino , Testes de Sensibilidade MicrobianaRESUMO
Cryptococcosis is a classical systemic opportunistic mycosis, primarily occurring among patients with significant immunologic impairment. However, this disease could also affect patients without any recognized immunologic defects, that is, phenotypically normal patients. The medical records of 29 non-HIV/nontransplant patients with cryptococcal disease during the period 2007-2014 were retrospectively reviewed. The most common site of infection was the central nervous system (n = 25, 86.2%), followed by the pulmonary system (n = 11, 37.9%) and blood (n = 2, 6.8%). Thoracic- and brain-computed tomography demonstrated abnormalities of 81.2% (n = 13) and 62.5% (n = 15), respectively. In sum, 22% (n = 6) of the patients experienced a significant underlying condition. More than one therapeutic regimen was used in 77.8% (n = 21) of the patients. The isolates were identified as being Cryptococcus neoformans species complex (n = 4, 36.4%) and Cryptococcus gattii species complex (n = 7, 63.6%). The overall mortality was 20.7% (n = 6). Herein, we presented the first case series of cryptococcosis in this specific population in São Paulo City, Brazil. The incidence of cryptococcosis in our hospital has not increased in recent years, and 77.8% (n = 21) of cases had no obvious predisposing factor. However, this disease remains associated with high mortality.
Assuntos
Criptococose/patologia , Cryptococcus/isolamento & purificação , Adolescente , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Brasil/epidemiologia , Infecções Fúngicas do Sistema Nervoso Central/epidemiologia , Infecções Fúngicas do Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Criptococose/diagnóstico por imagem , Criptococose/epidemiologia , Criptococose/microbiologia , Cryptococcus/classificação , Feminino , Fungemia/epidemiologia , Fungemia/patologia , Humanos , Pneumopatias Fúngicas/epidemiologia , Pneumopatias Fúngicas/patologia , Masculino , Pessoa de Meia-Idade , Radiografia Torácica , Estudos Retrospectivos , Análise de Sobrevida , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
Disseminated fusariosis has emerged as a significant, usually fatal infection in immunocompromised hosts despite antifungal treatment. We describe here two patients with acute leukemia who developed disseminated amphotericin-resistant fusariosis, and review of six studies of cases series in the literature. Two Fusarium solani strains were isolated from blood and skin cultures of one patient, and one strain from the blood culture of the second patient. Both patients died despite antifungal treatment. Strains were identified by sequencing of ITS1 and ITS4 regions. Random amplified polymorphic DNA analysis of the three F. solani isolates showed a low degree of similarity. Screening for Fusarium spp. contaminants within our facility was negative. Using the CLSI M-38-A2 broth dilution method and E tests(®), we found that the MICs were low for voriconazole (0.12 and 0.5 mg/L, respectively), unexpectedly high for amphotericin B (≥8 and ≥32 µg/mL, respectively) and itraconazole (≥16 mg/ml). Patients with leukemia or persistent neutropenia should be assessed for disseminated fungal infections, including biopsy and skin cultures. Antifungal susceptibility tests are important due to the possibility of the strains being amphotericin resistant. Treatments must be aggressive, with high doses of antifungals or combined therapy.
Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Fusariose/diagnóstico , Fusariose/patologia , Fusarium/efeitos dos fármacos , Leucemia Aguda Bifenotípica/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Idoso , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Farmacorresistência Fúngica , Evolução Fatal , Fusariose/microbiologia , Fusarium/isolamento & purificação , Humanos , Masculino , Testes de Sensibilidade Microbiana , Análise de Sequência de DNARESUMO
Causative agent in majority of VVC is Candida albicans, but infection due to non-C. albicans is common. Use of empiric antifungal therapy in Brazil due to syndromic management of vulvovaginitis could act as risk factor for increase resistance among VVC causative agents. From Mato Grosso patients, 160 with culture-proved among 404 women who had clinical symptoms of VVC, were enrolled in this study. 70 non-pregnant women and 90 pregnant women were included. Candida albicans was the most prevalent, representing 72.9% in the non-pregnant group and 92.3% in the pregnant group. Differences in species distribution were noted between the two groups, being C. parapsilosis the second more prevalent species among non-pregnant women. Susceptibility testing revealed high susceptibility to fluconazole (except for C. krusei), itraconazole, ketoconazole, and amphotericin B regardless the species (C. albicans, C. parapsilosis, C. tropicalis, C. glabrata, C. krusei) analyzed.
RESUMO
This is a retrospective observational study of clinical and epidemiologic data from bloodstream yeast infections over 5 years (2004-2008) in a tertiary-care hospital. During this period, there were 52 such infections, at a rate of 2.4 per 1,000 hospital admissions. Non-C. albicans Candida species and other genera were responsible for 82% of infections, with C. tropicalis and C. parapsilosis being the most common. In 2008 no C. albicans infections occurred. Several uncommon fungal pathogens were observed, including Trichosporon asahii, Rhodotorula spp. and Candida zeylanoides. Of 16 isolates tested, 3 (19%) were resistant to fluconazole, including one C. zeylanoides (MIC 8 microg/ml) and one C. tropicalis (MIC 16 microg/ml) isolate, as well as intrinsically resistant C. krusei. All isolates tested were susceptible to itraconazole (n = 7) and amphotericin B (n = 8). Yeast infections were associated with severe underlying diseases, mainly hematological/solid cancers (71%), hospitalization in the ICU (41%), central venous catheters (80%), and use of antimicrobials (94%). The overall mortality rate was 50%. Our finding of a predominance of non-C. albicans Candida species infection with uncommon yeasts, and fluconazole resistance, suggests the need for continuous surveillance of fungemia and of antibiotic susceptibility trends, in order to adopt treatment strategies applicable to particular healthcare institutions.
Assuntos
Candida/classificação , Candida/isolamento & purificação , Candidíase/epidemiologia , Candidíase/microbiologia , Fungemia/epidemiologia , Fungemia/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candidíase/mortalidade , Criança , Pré-Escolar , Feminino , Fungemia/mortalidade , Hospitais , Humanos , Lactente , Itraconazol/farmacologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Rhodotorula/classificação , Rhodotorula/isolamento & purificação , Trichosporon/classificação , Trichosporon/isolamento & purificação , Adulto JovemRESUMO
BACKGROUND: We aimed to assess susceptibility pattern of Candida species isolated from horticulturists with onychomycosis to four antifungal drugs and to compare the effectiveness of conventional identification methods with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS). METHODS: This study was conducted in a community garden located in Teresina, State of Piauí, Brazil, in the year 2014. The samples were identified through phenotypic methods and per MALDI-TOF MS, being used PCR as definitive identification test. The susceptibility pattern to four antifungal drugs was determined according to Clinical and Laboratory Standards Institute (CLSI). RESULTS: Fourteen clinical isolates from seven different species were identified by the phenotypic method and by MALDI-TOF MS, with an observed concordance of 71.4% between the two methods. C. albicans (28.6%), C. parapsilosis (21.4%), C. guilliermondii and C. metapsilosis (both with 14.3%) were the most frequent species. With the exception of C. krusei, all species were sensitive to the tested antifungal. CONCLUSION: This is the first study of antifungal susceptibility of Candida in Piauí, Brazil. With the exception of C. krusei, no species showed resistance to the antifungal drugs used. This study suggests constants updates from the public databases used in MALDI-TOF MS to provide a rapid and accurate mycological diagnosis.
RESUMO
One hundred and forty-one Candida species isolated from clinical specimens of hospitalized patients in Rio de Janeiro, Brazil, during 2002 to 2007, were analized in order to evaluate the distribution and susceptibility of these species to fluconazole. Candida albicans was the most frequent species (45.4%), followed by C. parapsilosis sensu lato (28.4%), C. tropicalis (14.2%), C. guilliermondii (6.4%), C. famata (2.8%), C. glabrata (1.4%), C. krusei (0.7%) and C. lambica (0.7%). The sources of fungal isolates were blood (47.5%), respiratory tract (17.7%), urinary tract (16.3%), skin and mucous membrane (7.1%), catheter (5.6%), feces (2.1%) and mitral valve tissue (0.7%). The susceptibility test was performed using the methodology of disk-diffusion in agar as recommended in the M44-A2 Document of the Clinical and Laboratory Standards Institute (CLSI). The majority of the clinical isolates (97.2%) was susceptible (S) to fluconazole, although three isolates (2.1%) were susceptible-dose dependent (S-DD) and one of them (0.7%) was resistant (R). The S-DD isolates were C. albicans, C. parapsilosis sensu lato and C. tropicalis. One isolate of C. krusei was resistant to fluconazole. This work documents the high susceptibility to fluconazole by Candida species isolated in Rio de Janeiro, Brazil.
Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidíase/epidemiologia , Infecção Hospitalar/epidemiologia , Fluconazol/farmacologia , Brasil/epidemiologia , Candida/classificação , Candidíase/microbiologia , Infecção Hospitalar/microbiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Fúngica , HumanosRESUMO
We reported a cryptococcal meningitis Aids-patient infected with a mating type VNI isolate showing filamentous cells in direct examination of cerebrospinal fluid. Clinical data, outcome, treatment features and microbiological findings were discussed.
RESUMO
The VITEK 2 system was evaluated for the identification of 74 Trichosporon invasive and non-invasive clinical isolates, comparing its results with the IGS1 sequencing. The system correctly identified Trichosporon asahii but not non-T. asahii isolates, which represented nearly 50% of the invasive infections in our nosocomial setting.
Assuntos
Técnicas de Tipagem Micológica/métodos , Técnicas de Tipagem Micológica/normas , Trichosporon/classificação , Trichosporon/genética , Tricosporonose/microbiologia , DNA Fúngico/análise , DNA Fúngico/genética , Genótipo , Humanos , Filogenia , Reprodutibilidade dos Testes , Tricosporonose/diagnósticoRESUMO
Chromoblastomycosis is a chronic subcutaneous disease caused by human contact with melanized fungioccurring mainly in tropical and subtropical zones worldwide. This study assessed 12 patients with chro-moblastomycosis from RondËonia, Brazil, Amazon region. In sum, 83.3% were men, 41.6% were from MonteNegro city, median age was 52.9 years, and median time to disease progression was 12.2 years. Lesions werelocated on the lower limbs (75%), and verruciform was prevalent form (66.6%). After 3 years of treatmentwith itraconazole, two patients were considered cured. The etiological agents were identified by the molec-ular sequence of the ribosomal internal transcribed spacer ITS1, 5.8S, and ITS2 region andß-tubulin genes.Eight strains were identified asFonsecaea pedrosoi, two wereF. nubica,and two wereRhinocladiella similis.The antifungal activity of five drugs was evaluated, and the most active drug was terbinafine (range minimalinhibitory concentration [MIC] 0.0150.12µg/ml), itraconazole (range MIC 0.030.5µg/ml) and voriconazole(range MIC 0.060.5µg/ml). The highest MIC was 5-fluorocytosine (range MIC 232µg/ml), and ampho-tericin B (range MIC 0.252µg/ml). In conclusion, the present study expanded the epidemiological diseasedatabase and described for the first timeF. nubicaandR. similisas chromoblastomycosis agents in theBrazilian Amazon region. Our results confirmed the importance of using molecular methods to identify themelanized fungi and stimulate the recognition of the disease in other places where no cases have beenreported.
Assuntos
Humanos , Cromoblastomicose , Ecossistema AmazônicoRESUMO
There are few reports concerning the in vitro antifungal susceptibility of clinical and environmental Cryptococcus gattii isolates. In this study, we performed polymerase chain reaction-restriction fragment length polymorphism to investigate the molecular subtypes of 50 clinical and 4 environmental Brazilian isolates of C. gattii and assessed their antifungal susceptibility for fluconazole (FLU) and amphotericin B (Amb) according to recent recommendations proposed for antifungal susceptibility testing of nonfermentative yeasts. Time-kill curve studies were performed using RPMI 1640 medium to analyze the fungicidal effect of AmB. We found 47 VGII (94%) molecular types and 3 VGI (6%) types among the clinical isolates. The environmental isolates were VGII (75%) subtype and VGI (25%) subtype. The FLU-MIC ranged from 1 to 64 mg L(-1), and MIC(50)/MIC(90) values were, respectively, 8/16 mg L(-1). For AmB, the MICs were low and homogeneous, ranging from 0.12 to 0.5 mg L(-1), for VGI or VGII. The time required to reach the fungicidal end point (99.9% killing) was 6 h for the majority of strains (64%), but viable cells of VGII were still present after 48 h of exposition. We pointed out the occurrence of high FLU-MICs for C. gattii isolates with highest values for VGII. Our data also suggest that the rate of killing of C. gattii by AmB is strain dependent, and viable cells of VGII genotype strains were still observed after an extended incubation time, addressing future studies to determine whether the in vitro fungicidal activity could be clinically relevant.
Assuntos
Criptococose/microbiologia , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/genética , Microbiologia do Solo , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Brasil , Cryptococcus gattii/classificação , Cryptococcus gattii/isolamento & purificação , Farmacorresistência Fúngica , Fluconazol/farmacologia , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Tipagem Micológica , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores de TempoRESUMO
The Candida parapsilosis group encompasses three species: C. parapsilosis, Candida orthopsilosis and Candida metapsilosis. These species are phenotypically indistinguishable, and molecular methods are needed for their detection. We analysed 152 unique blood culture isolates of the C. parapsilosis group obtained during 1997-2011. The isolates were screened by PCR amplification of the gene encoding secondary alcohol dehydrogenase, followed by digestion with the restriction enzyme BanI. Isolates with RFLP patterns distinct from those of the C. parapsilosis group were characterized as C. parapsilosis sensu stricto (90.8â%), C. orthopsilosis (8.6â%) and C. metapsilosis (0.6â%). Antifungal susceptibility tests indicated that all isolates were susceptible to itraconazole, amphotericin B and caspofungin. Although C. orthopsilosis and C. metapsilosis isolates were susceptible to fluconazole, higher MICs (≥2 mg l(-1)) were observed for C. orthopsilosis. Three isolates (2.0â%) of C. parapsilosis sensu stricto were resistant to voriconazole. Five C. parapsilosis isolates (3.3â%) were intermediate, and a single isolate (0.7â%) was resistant (MIC 16 mg l(-1)) to fluconazole. These data were confirmed using reference strains. It was observed that C. parapsilosis isolates were less susceptible to all triazoles, and this finding deserves further attention to assess the appearance of cross-resistance phenomena. In conclusion, C. metapsilosis and C. orthopsilosis are involved in a small but significant number of invasive infections in Brazil.
Assuntos
Antifúngicos/farmacologia , Candida/classificação , Candida/efeitos dos fármacos , Candidemia/epidemiologia , Candidemia/microbiologia , Brasil , Candida/genética , Candida/isolamento & purificação , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Tipagem Molecular/métodos , Técnicas de Tipagem Micológica/métodos , Micologia/métodos , Polimorfismo de Fragmento de Restrição , PrevalênciaRESUMO
BACKGROUND: Pytiriasis versicolor is an infectious disease caused by several Malassezia species which has a tendency to become relapsing or chronic. OBJECTIVES: This study was conducted in an attempt to investigate the clinical course of pityriasis versicolor with regard to the number of relapses after a 12-month therapy and correlate this number with isolates of Malassezia species. MATERIAL AND METHODS: 102 patients with clinical and laboratory diagnosis of pityriasis versicolor were monitored for 12 months to investigate the number of relapsing episodes of the disease. RESULTS: After appropriate treatment, pityriasis versicolor presented three types of clinical course: pityriasis versicolor without relapsing episodes (32.35%), relapsing pityriasis versicolor with one to four relapsing episodes (52.94% ) due to associated predisposing factors, and chronic pityriasis versicolor with more than four relapsing episodes (14.70%) with no relation to predisposing factors. CONCLUSIONS: The clinical course of pityriasis versicolor varied according to the number of relapsing episodes of the disease analyzed over a period of 12 months and can be classified as follows: pityriasis versicolor with clinical and mycological clearing, relapsing pityriasis versicolor and chronic pityriasis versicolor.
Assuntos
Malassezia/isolamento & purificação , Tinha Versicolor/prevenção & controle , Adolescente , Adulto , Distribuição por Idade , Idoso , Antifúngicos/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Cetoconazol/uso terapêutico , Malassezia/classificação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Distribuição por Sexo , Tinha Versicolor/classificação , Tinha Versicolor/tratamento farmacológico , Adulto JovemRESUMO
The authors report a case of pityriasis versicolor circinata whose isolated etiologic agent was Malassezia sympodialis in a 34-year-old woman. The isolation and identification of Malassezia sympodialis were accomplished with modified Dixon's agar, and the molecular method used to confirm the species was polymerase chain reaction and restriction fragment length polymorphism analysis (PCR-RFLP).
Assuntos
Malassezia/isolamento & purificação , Tinha Versicolor/microbiologia , Adulto , Feminino , HumanosRESUMO
Species of the genus Malassezia isolated were: Malassezia sympodialis (16.66%), Malassezia furfur (12.50%), Malassezia globosa (11.45%), and Malassezia slooffiae (2.10%). Malassezia sympodialis predominated in the study. The species of Malassezia identified did not show correlation with clinical variants and with the distribution of pityriasis versicolor lesions in relation to areas of the body.
Assuntos
Malassezia/classificação , Malassezia/isolamento & purificação , Tinha Versicolor/microbiologia , HumanosRESUMO
We reported a cryptococcal meningitis Aids-patient infected with a mating type VNI isolate showing filamentous cells in direct examination of cerebrospinal fluid. Clinical data, outcome, treatment features and microbiological findings were discussed
Assuntos
Humanos , Masculino , Adulto , HIV , Criptococose , Cryptococcus neoformansRESUMO
One hundred and forty-one Candida species isolated from clinical specimens of hospitalized patients in Rio de Janeiro, Brazil, during 2002 to 2007, were analized in order to evaluate the distribution and susceptibility of these species to fluconazole. Candida albicans was the most frequent species (45.4%), followed by C. parapsilosis sensu lato (28.4%), C. tropicalis (14.2%), C. guilliermondii (6.4%), C. famata (2.8%), C. glabrata (1.4%), C. krusei (0.7%) and C. lambica (0.7%). The sources of fungal isolates were blood (47.5%), respiratory tract (17.7%), urinary tract (16.3%), skin and mucous membrane (7.1%), catheter (5.6%), feces (2.1%) and mitral valve tissue (0.7%). The susceptibility test was performed using the methodology of disk-diffusion in agar as recommended in the M44-A2 Document of the Clinical and Laboratory Standards Institute (CLSI). The majority of the clinical isolates (97.2%) was susceptible (S) to fluconazole, although three isolates (2.1%) were susceptible-dose dependent (S-DD) and one of them (0.7%) was resistant (R). The S-DD isolates were C. albicans, C. parapsilosis sensu lato and C. tropicalis. One isolate of C. krusei was resistant to fluconazole. This work documents the high susceptibility to fluconazole by Candida species isolated in Rio de Janeiro, Brazil.
Assuntos
Humanos , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candidíase/epidemiologia , Infecção Hospitalar/epidemiologia , Fluconazol/farmacologia , Brasil/epidemiologia , Candida/classificação , Candidíase/microbiologia , Infecção Hospitalar/microbiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência FúngicaRESUMO
The in vitro activities of amphotericin B (AmB) were evaluated against 40 isolates of Cryptococcus neoformans using time-kill curves. The isolates were obtained from 20 AIDS patients with cryptococcal meningitis submitted to AmB therapy. Isolates were exposed in vitro to 1 microg/mL of AmB that represents a serum concentration of AmB, and the viable colony counts were determined over time. AmB exhibited fungicidal activity at 6 and 12 h for 70.6% of isolates, at 24 h for 7.3%, and at 48 h for 22% of isolates, respectively. This effect was not maximized when the test drug concentration was up to 4 times the AmB MIC for the isolates. Regrowth was observed in 17.5% of the isolates after fungicidal endpoint. With standard in vitro susceptibility testing, this tolerance phenomenon could not be assessed, and thus, these tests may underestimate the resistance of C. neoformans to AmB in vivo. AmB is the first-choice drug for the treatment of cryptococcosis in Brazil, and future studies using time-kill methodology are needed to estimate the predictive value of this test in the clinical failure.
Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Criptococose/microbiologia , Cryptococcus neoformans/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Brasil , Contagem de Colônia Microbiana , Cryptococcus neoformans/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Fatores de TempoRESUMO
The emergence of less common fungal pathogens has been increasingly reported in the last decade. We describe 25 cases of Rhodotorula spp. isolated from blood cultures at a large Brazilian tertiary teaching hospital from 1996-2004. We also investigated the in vitro activity of four antifungal drugs, using a standardized method. The median age of patients was 43 years. The majority of patients (88%) had a central venous catheter (CVC) and 10 (40%) were recipients of a bone marrow transplant. The episode was classified as a bloodstream infection (BSI) in 80% of the patients. Amphotericin B deoxycholate was the most common antifungal used and CVC was removed in 89.5% of the patients. Death occurred in four patients (17.4%), all classified as BSI. All strains were identified as R. mucilaginosa by conventional methods. Misidentification of the species was observed in 20% and 5% of the strains with the Vitek Yeast Biochemical Card and API 20C AUX systems, respectively. Amphotericin B demonstrated good in vitro activity (MIC50/90, 0.5 microg/ml) and the MICs for fluconazole were high for all strains (MIC50/90, >64 microg/ml).