Asunto(s)
Antituberculosos/uso terapéutico , Isoniazida/uso terapéutico , Mycobacterium tuberculosis/aislamiento & purificación , Rifampin/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Adulto , Anciano , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Estudios Prospectivos , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológicoRESUMEN
BACKGROUND: HIV-1 genotypic resistance test (GRT) has been widely used to monitor HIV infection but only few reports revealed the mutation patterns of non-B HIV-1 subtypes. OBJECTIVE: To evaluate the concordance of GRT and clinical treatment outcomes on different HIV-1 subtypes and monitor the mutation patterns and frequencies. STUDY DESIGN: Pre- and post-treatment plasma samples from 123 patients (39 treatment naïve and 84 treatment experienced) were tested by ViroSeq HIV-1 Genotyping System followed by analysis using the Stanford HIV database. The mutation patterns and frequencies developed in the pol gene were compared among subtypes. RESULTS: HIV-1 subtypes among patients in Hong Kong were mainly subtype B and CRF01_AE. Primary mutation was not detected among all pre-treatment samples. For post-treatment samples, primary mutations were only detected in the treatment failure group. The mutation patterns and frequencies were similar between CRF01_AE and subtype B viruses. However, the frequencies of L74V/I and K103N in the reverse transcriptase region were different between CRF01_AE and subtype B viruses. VirtualPhenotype was unable to analyze an in-frame insertion of arginine and isoleucine at protease codon 35 of one CRF01_AE isolate. CONCLUSIONS: This is the first report to demonstrate the high degree of concordance of longitudinal genotyping data and clinical treatment outcome in patients harboring different HIV-1 subtypes. Our findings shed light to the emergence of resistance mutations and its testing in CRF01_AE, which is relevant to other prevailing places in Asia.
Asunto(s)
Terapia Antirretroviral Altamente Activa , Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/clasificación , VIH-1/efectos de los fármacos , Mutación , Algoritmos , Infecciones por VIH/virología , VIH-1/genética , Hong Kong , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Juego de Reactivos para Diagnóstico , Insuficiencia del Tratamiento , Resultado del TratamientoRESUMEN
Four cases of bacteremia caused by Staphylococcus aureus with heteroresistance to vancomycin (hetero-VRSA) were described. In at least two of these four mortalities, the cause of death was temporally related to the hetero-VRSA bacteremia. The vancomycin and teicoplanin MICs of the resistant subpopulations of these four hetero-VRSA were 8 and 24 microg/ml, respectively. All isolates were producers of beta-lactamase, produced penicillin-binding protein PBP2a, and possessed the mecA gene accounting for methicillin resistance. Thickening of the peptidoglycan cell wall was observed by electron microscopy. When ampicillin was combined with vancomycin, in vitro synergism was detected using the checkerboard titration method (epsilonFIC = 0.13). The use of vancomycin plus ampicillin-sulbactam could be a viable option in treating severe hetero-VRSA infection in view of the higher affinity of ampicillin toward PBP2a.