Revista Peruana de Medicina Experimental y Salud Publica
versión impresa ISSN 1726-4634
BALDEVIANO V, Christian et al. Perfiles genéticos (RFLP-IS6110) y resistencia a drogas en aislamientos de M. tuberculosis de pacientes internados en un hospital referencial del Callao, Perú. Rev. perú. med. exp. salud publica [online]. 2003, vol.20, n.2, pp. 72-77. ISSN 1726-4634.
Objective: To assess the frequency and clustering of DNA fingerprinting (RFLP-IS6110), and to determine levels of drug-resistance among M. tuberculosis isolates from smear-positive pulmonary tuberculosis patients (SP-PTB) from a general hospital in Callao. Materials and methods: Patients with SP-PTB hospitalized in the Hospital Nacional Daniel A Carrión from August 2000 to February 2001were included in the study. Drug-susceptibilty testing to the four first-line drugs (INH, RIF, SM, EMB) was performed using the proportion method, and DNA fingerprinting analysis was performed using the standard IS6110-RFLP technique. Patient information was collected from clinical and laboratory records. Results: From 74 isolates, the number of IS6110-bands varied from 2 to 16, 4 isolates (5,5%) showed less than 5 bands. Overall, 50 DNA fingerprinting profiles were observed in 70 patients. 34 isolates (48,6 %) were grouped in 14 clusters and 36 isolates were isolated ocurrences. Drug resistance in never treated and previoulsy treated patients was 45,2% and 71,1%, respectively. Multidrug-resistance was 16,1% and 36,8%, respectively. 10 out of 14 clusters had at least one drug-resistant isolate. One cluster involved 6 drug-resistant isolates. Conclusion: No evidence of clonal spread of a particular strain was observed. However, we found clusters grouping drug-resistant and drug-susceptible patients. Our results suggests that there are genotypes associated with drug resistance, which could indicates ongoing transmission of drug-resistant M. tuberculosis strains in Callao. A population-based study is necessary to confirm our results.
Palabras llave : Tuberculosis; M. Tuberculosis; Drug resistanse; Genetic code; polymorphism; restriction fragment length; Callao; Perú.