Genetic profile of Mycobacterium tuberculosis and treatment outcomes in human pulmonary tuberculosis in Tanzania.

Information on the different spoligotype families of Mycobacterium tuberculosis in Tanzania is limited, and where available, restricted to small geographical areas. This article describes the genetic profile of M tuberculosis across Tanzania and suggests how spoligotype families might affect drug resistance and treatment outcomes for smear positive pulmonary tuberculosis patients in Tanzania. We conducted the study from 2006 to 2008, and the isolates were obtained from samples collected under the routine drug resistance surveillance system. The isolates were from specimens collected from 2001 to 2007, and stored at the Central and Reference Tuberculosis Laboratory. A total of 487 isolates from 23 regions in the country were spoligotyped. We were able to retrieve clinical information for 446 isolates only. Out of the 487 isolates spoligotyped, 195(40.0%) belonged to the Central Asian (CAS) family, 84 (17.5%) to the Latin American Mediterranean (LAM) family, 49 (10.1%) to the East-African Indian (EAI) family, and 33 (6.8%) to the Beijing family. Other isolates included 1 (0.2%) for H37Rv, 10 (2.1%) for Haarlem, 4 (0.8%) for S family, 58 (11.9%) for T family and 52 (10.7%) for unclassified. No spoligotype patterns were consistent with M bovis. Regarding treatment outcomes, the cure rate was 80% with no significant variation among the spoligotype families. The overall level of MDR TB was 2.5% (3/12 1), with no significant difference among the spoligotype families. All Beijing strains (11.8%, 30/254) originated from the Eastern and Southern zones of the country, of which 80% were from Dar es Salaam. Isolates from the CAS and T families were reported disproportionately from the Eastern-Southern zone, and EAI and LAM families from the Northern-Lake zones but the difference was not statistically significant. Five isolates were identified as non-tuberculous Mycobacteria. In conclusion, M. tuberculosis isolates from pulmonary tuberculosis cases in Tanzania were classified mostly within the CAS, LAM, and EAI and T families, while the Beijing family comprised about 7% isolates only. Consistently good treatment outcomes were recorded across these spoligotype families. The proportion of drug resistance strains was low. The findings also suggest variation of spoligotype families with varying geographical localities within the country, and identify this area for further research to confirm this finding.

Genetic profile of Mycobacterium Tuberculosis and Treatment Outcomes in Human Pulmonary Tuberculosis in Tanzania

Information on the different spoligotype families of Mycobacterium tuberculosis in Tanzania is limited; and where available; restricted to small geographical areas. This article describes the genetic profile of M. tuberculosis across Tanzania and suggests how spoligotype families might affect drug resistance and treatment outcomes for smear positive pulmonary tuberculosis patients in Tanzania. We conducted the study from 2006 to 2008; and the isolates were obtained from samples collected under the routine drug resistance surveillance system. The isolates were from specimens collected from 2001 to 2007; and stored at the Central and Reference Tuberculosis Laboratory. A total of 487 isolates from 23 regions in the country were spoligotyped. We were able to retrieve clinical information for 446 isolates only. Out of the 487 isolates spoligotyped; 195(40.0) belonged to the Central Asian (CAS) family; 84 (17.5) to the Latin American Mediterranean (LAM) family; 49 (10.1) to the Latin American Mediterranean (LAM) family; 49 (10.1) to the East-African Indian (EAI) family; and 33 (6.8) to the Beijing family. Other isolates included 1 (0.2) for H37Rv; 10 (2.1) for Haarlem; 4 (0.8) for S family; 58 (11.9) for T family and 52 (10.7) for unclassified. No spoligotype patterns were consistent with M. bovis. Regarding treatment outcomes; the cure rate was 80 with no significant variation among the spoligotype families. The overall level of MDR TB was 2.5 (3/121); with no significant difference among the spoligotype families. All Beijing strains (11.8; 30/254) originated from the Eastern and Southern zones of the country; of which 80 were from Dar es Salaam. Isolates from the CAS and T families were reported disproportionately from the Eastern-Southern zone; and EAI and LAM families from the Northern-Lake zones but the difference was not statistically significant. Five isolates were identified as non-tuberculous Mycobacteria. In conclusion; M. tuberculosis isolates from pulmonary tuberculosis cases in Tanzania were classified mostly within the CAS; LAM; and EAI and T families; while the Beijing family comprised about 7 isolates only. Consistently good treatment outcomes were recorded across these spoligotype families. The proportion of drug resistance strains was low. The findings also suggest variation of spoligotype families with varying geographical localities within the country; and identify this area for further research to confirm this finding

Anti-tuberculosis drug resistance pattern among pulmonary tuberculosis patients with or without HIV infection in Mwanza, Tanzania.

Anti-tuberculosis drug resistance is a major problem in tuberculosis (TB) control, particularly multi-drug resistance TB (MDR-TB). The objective of this study was to determine the prevalence of primary and acquired anti-TB drug resistance among newly diagnosed pulmonary TB (PTB) and relapse cases. Sputa were collected from newly diagnosed and relapse PTB patients. Drug susceptibility tests (DST) were performed on sputum culture positive isolates of Mycobacterium tuberculosis using resistance ratio method on four first-line anti-TB drugs: rifampicin, isoniazid, ethambutol and streptomycin. Demographic and anthropometric information was collected and HIV status was determined. Of the 523 culture positive isolates, DST results were available for 503 (96%), 455 were new and 48 were relapse cases. Resistance to at least one of the four drugs was observed in 7.8% (39/503) of the isolates, 7.3% (33/455) were new and 12.5% (6/48) were from relapse cases. Mono resistance to isoniazid was higher in both among new 45.5% (15/33) and relapse 50.0% (3/6) cases. Resistance to rifampicin and streptomycin alone was equal 4/33 (12.1%) and only among new cases. Resistance to ethambutol alone was only one among new cases. Overall MDR-TB prevalence was 2.4% (12/503), nine were new and three were relapse cases. MDR-TB was 17.9% (7/39) for rifampicin and isoniazid. Prevalence of HIV was 43.3% and was similar among new and relapse cases and not risk factor for drug resistance. Majority of PTB patients (52%) had BMI below 18 kg/m2. Those with BMI greater than 18 kg/m2 were more likely to develop drug resistance than those with BMI below 18 kg/m2 (P=0.004). With the resurgence of TB and the high prevalence of HIV among TB patients, prevalence of drug resistance is still low both among new and relapses cases. Despite the current low drug resistance, there is a need for continuous monitoring of the resistance.