ABSTRACT INTRODUCTION By the end of 2017, there were more than 28,000 individuals living with HIV in Cuba, over 80% receiving antiretroviral therapy, which dramatically reduces viral replication, improves immune status and decreases risk of transmission. These results could be jeopardized by emergence of HIV-1 drug resistance. In 2009, a test for HIV-1 genotypic resistance was introduced in routine clinical practice in Cuba. OBJECTIVE Investigate antiretroviral resistance and its relation to subtype distribution in HIV-1 treatment-naïve and previously treated patients in Cuba. METHODS Resistance and HIV-1 subtype distribution were determined in 342 antiretroviral treatment-naïve patients and 584 previously treated for HIV-1 whose blood specimens were sent to the Pedro Kourí Tropical Medicine Institute during 2009–2014. Transmitted drug resistance was determined using the Calibrated Population Resistance Tool v.6. Drug resistance analysis was conducted using the algorithm Rega v9.1.0. RESULTS Prevalence of transmitted drug resistance was 11.4%, and 41% of mutated viruses exhibited dual-class resistance to nucleoside reverse transcriptase inhibitor and non-nucleoside reverse transcriptase inhibitor. Overall, 84.9% of patients had ≥1 resistance mutation, 80% had ≥1 nucleoside reverse transcriptase inhibitor mutation, 71.4% had ≥1 non-nucleoside reverse transcriptase inhibitor mutation and 31.7% had ≥1 protease inhibitor mutation. K65R and K101E mutations were significantly more frequent in subtype C, L210W in CRF19_cpx, and M47V/I in CRF BGs (20, 23, 24). Full class resistance to nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors and multidrug resistance were detected in 21.2%, 32.4%, 8% and 4.1% of patients, respectively. Average percentage resistance to nucleoside reverse transcriptase inhibitor, protease inhibitor, full class resistance to nucleoside reverse transcriptase inhibitor, protease inhibitor and multidrug resistance increased in patients failing two or more regimens. Nevertheless, after 2011, a declining trend was observed in the frequency of multidrug resistance and full class resistance to nucleoside reverse transcriptase inhibitors and protease inhibitors. CONCLUSIONS Detected levels of transmitted drug resistance highlight the need for a national surveillance study in treatment-naïve patients. Resistance prevalence is high in previously treated patients but appears to be decreasing over time. The frequency of resistance mutations in recombinant forms of HIV in Cuba needs further study.
Introduction: human leptospirosis is a communicable systemic zoonosis caused by the invasive bacteria Leptospira interrogans sensu lato complex. Numerous methods are used for serodiagnosis of this disease, including the ELISA tests. Objectives: to implement a new commercial serological ELISA test (SD Leptospira ELISA-IgM, SD Bioline, Korea) for screening of IgM antibodies and for identification of Leptospira serogroups in positive sera. Methods: twenty seven and sixty one sera, with/without IgM antibodies to leptospires, respectively, were studied. They had been taken from patients suspected of having leptospirosis. The microscopic agglutination test with live antigens (MAT) was the reference method. In addition, other commercial systems such as SD Leptospira IgM Lateral Flow and indirect hemagglutination (HAT) tests were comparatively used. Results: all the 27 sera with antibodies against Leptospira were positive according to SD Leptospira ELISA-IgM, 20 sera were found positive by SD Lateral Flow Igm test and 9 sera by the indirect HAT test. Of the 61 sera without antibodies to leptospires, 9 and 8 were positive by SD Leptospira ELISA-IgM and SD Leptospira IgM Lateral Flow test, respectively. Serogroups Canicola and Ballum were predominant in positive sera tested by the commercial system under evaluation. The agreement coefficient between SD Leptospira ELISA-IgM and MAT was 89.77 %. Conclusions: SD Leptospira ELISA-IgM showed higher positivity rate than the other systems in the studied sera; this aspect would support its possible introduction in Cuba. The great reactivity of the antigen used in the system was confirmed, which indicates that active laboratory surveillance of leptospiral serogroups should be kept nationwide.
Introducción: la leptospirosis humana es una zoonosis sistémica y transmisible producida por bacterias invasivas del complejo Leptospira interrogans sensu lato. Numerosos métodos se utilizan para el serodiagnóstico de esta entidad clínica, dentro de los cuales se encuentra ELISA. Objetivos: aplicar un nuevo sistema serológico comercial de ELISA, para la pesquisa de anticuerpos IgM contra leptospiras e identificar los serogrupos de leptospiras presentes en los sueros positivos por este sistema. Métodos: de pacientes sospechosos de leptospirosis se estudiaron 27 y 61 sueros con anticuerpos contra leptospiras y sin estos, respectivamente. La técnica de microaglutinación con antígenos vivos (MAT) se utilizó como método de referencia. Los sistemas comerciales de SD Leptospira ELISA-IgM, SD flujo lateral Leptospira IgM y la hemoaglutinación indirecta (HAT) fueron comparativamente empleados. Resultados: 27 sueros con anticuerpos contra leptospiras resultaron positivos por SD Leptospira ELISA-IgM, 20 por SD flujo lateral Leptospira IgM y 9 por hemoaglutinación indirecta. De 61 sueros sin anticuerpos contra leptospiras, 9 y 8 resultaron positivos, respectivamente, por SD Leptospira ELISA-IgM y por SD flujo lateral Leptospira IgM. Los serogrupos Ballum y Canicola predominaron en los sueros positivos por el sistema comercial. La coincidencia entre SD Leptospira ELISA-IgM y la técnica de microaglutinación con antígenos vivos fue de 89,77 %. Conclusiones: SD Leptospira ELISA-IgM muestra una mayor positividad en los sueros estudiados, lo que avalaría su posible introducción en Cuba. Se confirma la amplia reactividad del antígeno usado en SD Leptospira ELISA-IgM, lo cual sugiere mantener una activa vigilancia de laboratorio sobre los serogrupos de leptospiras, a nivel nacional.