INVASIVE FUNGAL INFECTION

INVASIVE FUNGAL INFECTION BUI THI VAN NGA Microbiology depaterment Invasive fungal infection  Invasive fungal infection are a significant cause of morbidity and mortality worldwide  Candida species are the most common fungal pathogens encountered  The term invasive candidiasis: candidemia, endocarditis, meningitis and other forms of deep organ involvement Fungal species  Candida species: C.albicans, C.tropicalis, C.krusei, C.glabrata…  Aspergillus  Cryptococcus.spp  Fusarium.spp  Zygomycetes (mucormycose) Risk factors for invasive candidiasis  Candida colonization  Broad- spectrum antimicrobials  Malignancy  Chemotherapy/immunosuppressive medications  Transplantation  Renal failure  … Invasive Candidiasis  The presence of candida in a blood culture should never be perceived simply as a contaminant and always investigation for possible soures  Blood culture are positive in only 50% to 70% of patients with invasive candidiasis Invasive Candidiasis  However, a positive culture from a nonsterile site often provides little evidence to distinguish between infection and colonization  Nonculture – based method has been vigorously sought: 1,3-β- D glucan,which is a major component of fungal cell wall, can be detected Invasive Candidiasis  This test has sensitivity of 75% to 100% and a specificity of 88% to 100%  It is s broad – spectrum assay that detects Aspergillus, candida, fusarium, and saccharomyces species, thus careful intepretation is needed  Early empiric therapy in high-risk patients pending culture results is justifiable Empiric treatment of candidemia  Fluconazole is an appropriate choice for nonneutropenic, hemodynamically stable patients  In patients who are neutropenic, hemodynemically unstable,or who are being treated in units with high rates of infection with fluconazole resistant specsies treatment with an echinocandin is preferred until species identification of the Candida isolate is made Invasive Aspergillosis  Although a much less common cause of invasive disease  But it is important for high risk patients? Risk factors for invasive aspergillus  Prolonged neutropenia (>10 days)  Heamatopoietic stem cell transplantation  Solid organ transplantation  Corticosteroid/other immunosuppressive therapy  Advanced HIV  Chronic granulomatous disease Invasive Aspergillosis  Sinopulmonary involvement is the most common manifestation  Computed tomography may suggest the diagnosis with findings such as the ‘ halo sign’ Invasive Aspergillosis  However, this feature can be seen with other angioinvasive infection, So it is far from diagnostic  Serological tests: galactomannan ( sensitivity 29% to 100%, specificity greater than 85%, false positive results may aslo occur in patients receiving Piperacillin-tazobactam), 1,3-β- D glucan  This assays can be used as a diagnostic adjunct but should not be used as sole criterion for diagnostic Therapy for invasive aspergillosis  Voriconazole is recommended as fist – line therapy  The comparing amphotericin B and voriconazole as initial therapy, voriconazole was associated with improved survival 71% and 58% with amphotericin B Activity of antifungal agents Fungus Fluconazole Voriconazole Echinocadin * Aphotericin B C.albicans + + + + C.parapsilosis + + +/- + + + + DD/- +/- + + C.krusei - + + + Aspergilus spp - + + + C.tropicalis C.glabrata (+) susceptibility, (-) resistance, DD dose dependent - susceptibility * Only caspofungin and anidulafungin approved for candidemia THANKS FOR ATTENTION .. .Invasive fungal infection  Invasive fungal infection are a significant cause of morbidity and mortality worldwide  Candida species are the most common fungal pathogens encountered... 70% of patients with invasive candidiasis Invasive Candidiasis  However, a positive culture from a nonsterile site often provides little evidence to distinguish between infection and colonization... factors for invasive candidiasis  Candida colonization  Broad- spectrum antimicrobials  Malignancy  Chemotherapy/immunosuppressive medications  Transplantation  Renal failure  … Invasive