RESUMO
The overgrowth of normal flora escaping the action of sputum processing chemicals is the major problem in broth-based tuberculosis (TB) detection systems. The use of phages to control the overgrowth of normal flora in processed sputum samples has already been established. Phage lysin and its supplementation to phagebiotics for the effective control of normal flora in sputum specimens were evaluated. Crude lysin was prepared from phage host mixture using standard procedures. About 120 sputum samples processed with 4% NaOH were collected and used to evaluate the effect of lysin, phagebiotics and phagebiotics supplemented with lysin on the overgrowth of normal flora. The effect of phagebiotics and lysin on the growth and retrieval of Mycobacterium tuberculosis was studied by conventional methods and the luciferase reporter phage (LRP) assay. Lysin alone and phagebiotics supplemented with lysin arrested the growth of normal flora in a significantly greater number of samples than phagebiotics alone. Lysin and phagebiotics did not show any inhibitory activity on M. tuberculosis. The use of antibiotics can be replaced by lysin or phagebiotics supplemented with lysin to control the overgrowth of normal flora in processed sputum samples without hampering the viability of M. tuberculosis.
Assuntos
Fagos Bacilares/fisiologia , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Hidrolases/metabolismo , Mycobacterium tuberculosis/crescimento & desenvolvimento , Escarro/microbiologia , Tuberculose/diagnóstico , Fagos Bacilares/enzimologia , Técnicas Bacteriológicas , Descontaminação/métodos , Bactérias Gram-Negativas/virologia , Bactérias Gram-Positivas/virologia , Humanos , Luciferases , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Sensibilidade e Especificidade , Hidróxido de Sódio , Proteínas Virais/metabolismoRESUMO
BACKGROUND: The present study provides an estimate of the prevalence of bacteriologially positive pulmonary tuberculosis in Jabalpur, a district in central India. METHODOLOGY/PRINCIPAL FINDINGS: A community based cross-sectional survey was undertaken in Jabalpur District of the central Indian state of Madhya Pradesh. A stratified cluster sampling design was adopted to select the sample. All eligible individuals were questioned for pulmonary symptoms suggestive of TB disease. Two sputum samples were collected from all eligible individuals and were examined by Ziehl-Neelsen smear microscopy and solid media culture methods. Of the 99,918 individuals eligible for screening, 95,071 (95.1%) individuals were screened. Of these, 7,916 (8.3%) were found to have symptoms and sputum was collected from 7,533 (95.2%) individuals. Overall prevalence of bacteriologically positive PTB was found to be 255.3 per 100,000 population (95% C.I: 195.3-315.4). Prevalence was significantly higher (p<0.001) amongst males (355.8; 95% C.I: 304.4-413.4) compared with females (109.0; 95% C.I: 81.2-143.3). Prevalence was also significantly higher in rural areas (348.9; 95% C.I: 292.6-412.8) as compared to the urban (153.9; 95% C.I: 123.2-190.1). CONCLUSIONS/SIGNIFICANCE: The TB situation in Jabalpur district, central India, is observed to be comparable to the TB situation at the national level (255.3 versus 249). There is however, a need to maintain and further strengthen TB control measures on a sustained and long term basis in the area to have a significant impact on the disease prevalence in the community.