Multidrug-resistant tuberculosis in Port-au-Prince, Haiti / Tuberculosis multirresistente en Puerto Príncipe, Haití

OBJECTIVE: To determine the prevalence of multidrug-resistant tuberculosis (MDR-TB) among patients with new smear-positive pulmonary TB in Port-au-Prince, Haiti. METHODS: Sputum samples were cultured from 1 006 patients newly diagnosed with TB in 2008. The core region of the rpoB gene that is associated with resistance to rifampin was sequenced. All isolates with rpoB mutations were sent to the New York State reference laboratory for conventional drug susceptibility testing (DST). All isolates were also tested with the GenoType MTBDRplus line-probe assay. RESULTS: Mycobacterium tuberculosis was isolated from 906 patients. Twenty-six (2.9 percent) of the isolates had missense mutations or deletions in rpoB and were resistant to rifampin by DST. All 26 were also resistant to isoniazid and classified as MDR-TB. Forty-six control isolates without rpoB mutations were found to be rifampin sensitive by DST. The GenoType MTBDRplus line-probe assay correctly identified 26 MDR-TB strains. It misclassified one pansusceptible isolate as rifampin resistant. CONCLUSIONS: This study shows an MDR-TB prevalence of 2.9 percent in newly diagnosed TB patients in Haiti and suggests that rpoB sequencing and hybridization assays are good screening tools for early detection of MDR-TB.

OBJETIVO: Determinar la prevalencia de tuberculosis (TB) multirresistente en pacientes con TB pulmonar nueva con baciloscopia positiva en Puerto Príncipe, Haití. MÉTODOS: Se cultivaron muestras de esputo de 1 006 pacientes con diagnóstico reciente de tuberculosis efectuado durante el 2008. Se secuenció la región nuclear del gen rpoB, que se asocia con la resistencia a la rifampicina. Todos los aislados con mutaciones de rpoB se enviaron al laboratorio de referencia del estado de Nueva York para llevar a cabo un antibiograma convencional. Todos los aislados se estudiaron también con el ensayo de sonda lineal GenoType MTBDRplus. RESULTADOS: Se aisló Mycobacterium tuberculosis de 906 pacientes. Veintiséis (2,9 por ciento) de los aislados presentaban mutaciones de sentido erróneo o deleciones en rpoB y fueron resistentes a la rifampicina en el antibiograma. Los 26 aislados fueron resistentes también a la isoniacida y se clasificaron como TB multirresistente. Cuarenta y seis aislados de control sin mutaciones de rpoB resultaron sensibles a la rifampicina en el antibiograma. El ensayo de sonda lineal GenoType MTBDRplus identificó correctamente a las 26 cepas de TB multirresistente y clasificó de manera errónea un aislado sensible a múltiples fármacos como resistente a la rifampicina. CONCLUSIONES: Este estudio revela una prevalencia de TB multirresistente de 2,9 por ciento en los pacientes con TB recién diagnosticada en Haití e indica que los ensayos de secuenciación e hibridación de rpoB son estudios de detección sistemática adecuados para la detección temprana de la TB multirresistente.

Prevention of mother-to-child transmission of HIV in Haiti / Prevención de la transmisión del VIH de madre a hijo en Haití

OBJECTIVES: To describe the effectiveness of a program designed to reduce the rate of mother-to-child transmission (MTCT) of HIV at the primary HIV testing and treatment center in Haiti between 1999 and 2004. METHODS: All pregnant, HIV-positive women who attended the major HIV testing and treatment clinic in Port-au-Prince, Haiti, between March 1999 and December 2004 were asked to participate in an MTCT prevention program. Of the 650 women who participated, 73.3 percent received zidovudine (AZT), 2.9 percent received nevirapine (NVP), and 10.1 percent received triple-drug therapy when it became available in 2003 and if clinical/laboratory indications were met. Approximately 13.8 percent received no antiretroviral medication. All participants received cotrimoxazole prophylaxis and infant formula for their children. Kaplan-Meier survival analysis and the log rank test were used to evaluate program impact on child survival. RESULTS: Complete data were available for 348 mother-infant pairs who completed the program to prevent MTCT of HIV. The rate of MTCT in the study was 9.2 percent (95 percent CI: 6.14-12.24), in contrast to the historical mother-to-child transmission rate of 27 percent in Haiti. HIV-positive infants were less likely to survive than HIV-negative infants at 18 months of follow-up (χ2 = 19.06, P < .001, log rank test). Infant survival improved with early pediatric diagnosis and antiretroviral treatment. CONCLUSIONS: The MTCT prevention program described proved to be feasible and effective in reducing vertical HIV transmission in Haiti. The authors emphasize the need to expand testing, extend services to rural areas, and implement early HIV diagnosis to reduce infant mortality.

OBJETIVOS: Describir la eficacia de un programa diseñado para reducir la tasa de transmisión del VIH de madre a hijo (TMH) en el principal centro de diagnóstico y tratamiento de esa infección en Haití entre 1999 y 2004. MÉTODOS: Se invitó a participar en un programa para la prevención de la TMH a todas las embarazadas positivas al VIH que asistían a la clínica principal de diagnóstico y tratamiento de la infección por el VIH en Puerto Príncipe, Haití, entre marzo de 1999 y diciembre de 2004. De las 650 mujeres que participaron, 73,3 por ciento recibieron zidovudina (AZT), 2,9 por ciento nervirapine (NVP) y 10,1 por ciento tripleterapia cuando esta se hizo disponible en 2003 y cumplían los indicadores clínicos y de laboratorio requeridos. Aproximadamente 13,8 por ciento no recibió medicamentos antirretrovirales. Todas las participantes recibieron el tratamiento profiláctico con cotrimoxazole y fórmula infantil para sus hijos. Para evaluar el impacto del programa sobre la supervivencia infantil se aplicó el análisis de supervivencia de Kaplan-Meier y la prueba de rangos logarítmicos. RESULTADOS: Se obtuvieron los datos completos de 348 parejas madre-hijo que terminaron el programa de prevención de la TMH del VIH. La tasa de TMH en el estudio fue de 9,2 por ciento (intervalo de confianza de 95 por ciento: 6,14 a 12,24), frente a una tasa de TMH histórica en Haití de 27 por ciento. A los 18 meses de seguimiento, los niños positivos al VIH presentaron una menor probabilidad de supervivencia que los negativos (χ2 = 19,06; P < 0,001; prueba de rangos logarítmicos). La supervivencia de los niños aumentó con el diagnóstico y el tratamiento antirretroviral pediátricos tempranos. CONCLUSIONES: El programa de prevención de la TMH descrito demostró su factibilidad y eficacia para reducir la transmisión vertical del VIH en Haití. Los autores sub rayan la necesidad de extender el tamizaje y los servicios a áreas rurales, así como de implementar...

Transmision perinatal del virus de la inmunodeficiencia humana / Perinatal transmission of the human immunodeficiency virus

Transmission of human immunodeficiency virus (HIV) from an infected mother to her fetus or infant occurs in utero and probably during labor and delivery. Athough the risk seems low, transmission via breast milk can also occur; breast-feeding during the pediod of seroconversión of the mother may carry relatively more risk. Because of the limitations of conventional HIV testing in infants, it is difficult to determine the rate of transmission from an infected mother to her fetus of infant. The transmission rate is probably between 20 percent and 60 percent, depending on the mother's health status. (the rate is higher in women who have more advanced disease.) As HIV spreads worlwide and more women get infected, a growing number of children are acquiring the infection perinatally. Although the actual numbers of pediatric AIDS cases and HIV-infected children are unknown, perinatal HIV infection is a significant problem, particularly in pattern 2 countries where HIV is spread primarily by heterosexual contac. Children in these countries may account for up to 35 percent of all AIDS cases, even though a large proportion of HIV infected children die of common childhood diseases before they develop clinical AIDS. In pattern 1 countries, where HIV is prdominantly affecting homosexual and bisexual men, children are being infected by mothers who have acquired the infection through intravenous drug abuse or