Comparison of bacteriological conversion and treatment outcomes among MDR-TB patients with and without diabetes in Mexico: Preliminary data.

Diabetes mellitus (DM) is a well-known risk factor for tuberculosis (TB). However, it is not known to what extent DM affects the outcome in patients with multidrug-resistant (MDR-TB) and extensively drug-resistant TB (XDR-TB) treated with second-line anti-TB drugs. The objective of this study was to compare the microbiological evolution (sputum smear and culture conversion) and final outcomes of MDR/XDR-TB patients with and without DM, managed at the national TB reference centre in Mexico City. RESULTS: Ninety patients were enrolled between 2010 and 2015: 73 with MDR-TB (81.1%), 11 with pre-XDR-TB (e.g. MDR-TB with additional resistance to one injectable drug or a fluoroquinolone, 12.2%) and 6 (6.7%) with XDR-TB. Out of these, 49 (54.4%) had DM and 42 (86%) were undergoing insulin treatment. No statistically significant differences were found in treatment outcomes comparing DM vs. non-DM MDR-TB cases: 18/32 (56.3%) of DM cases and 19/24 (79.2%) non DM patients achieved treatment success (p=0.07). The time to sputum smear and culture conversion was longer (although not statistically) in patients without DM, as follows: the mean (±SD) time to sputum smear conversion was 53.9 (±31.4) days in DM patients and 65.2 (±34.8) days in non-DM ones (p=0.15), while the time to culture conversion was 66.2 (±27.6) days for DM and 81.4 (±37.7) days for non-DM MDR-TB cases (p=0.06). CONCLUSIONS: The study results support the Mexican National TB programme to strengthen its collaboration with the DM programme, as an entry point for TB (and latent TB infection) screening and management.

Diabetes modifies the male:female ratio in pulmonary tuberculosis.

SETTING: Socio-cultural factors have been invoked to explain the male predominance among patients with pulmonary tuberculosis, but there is no conclusive evidence of their role. OBJECTIVE: To assess male predominance in a group of diabetics with pulmonary tuberculosis compared with patients with pulmonary tuberculosis alone. DESIGN: Clinical records of in-patients with pulmonary tuberculosis and with (TBDM group, n = 202) or without (TB group, n = 226) diabetes mellitus were reviewed, and the male percentages in each of six age groups (15-29, 30-39, 40-49, 50-59, 60-69, > or = 70 years) calculated. RESULTS: In the TB group, no gender difference (51% males) was found in the first age period, followed by a male predominance thereafter (71%, 68%, 75%, 63% and 58%). The TBDM group showed a similar pattern in the first two age groups (56% and 74%), followed by a steadily decline (r(S) = -0.90, P = 0.04) in male percentage (60%, 44%, 45%, 27%), leading to a female predominance after age 50. The association of age and gender was also corroborated by logistic regression in TBDM (P = 0.02), but not in TB (P = 0.19) patients. CONCLUSIONS: Diabetes was associated with a progressive shift of male predominance in pulmonary tuberculosis. Because diabetes is a disease that affects social activities similarly in men and women, our results suggest that factors other than socio-cultural ones are also important for determining the male predominance in pulmonary tuberculosis.

Results of a 12-month regimen for drug-resistant pulmonary tuberculosis.

SETTING: Several therapeutic regimens for drug-resistant tuberculosis have been suggested, most of them with a total duration of 18-24 months. OBJECTIVE: To report our experience using a shorter regimen. DESIGN: Fifty patients with drug-resistant pulmonary tuberculosis were managed by withdrawing all anti-tuberculosis drugs until the results of a drug sensitivity test were obtained (approximately 3 months), and then a 12-month self-administered regimen with four to six anti-tuberculosis drugs at full daily doses was initiated, based primarily on the sensitivity test and secondarily on the history of previous treatment. RESULTS: In 31 patients treatment was completed as planned, in six it was irregular and 13 definitively abandoned it. In the best scenario, 90.3% (28/31) of patients with full treatment were cured; this outcome was similar for both multidrug-resistant (MDR, n = 18, 88.9%) and non-MDR (n = 13, 92.3%) patients. Six months later, the relapse rate was 4.8%, and after a 5-year follow-up 14 out of 18 cured patients who were located remained asymptomatic (77.8%). If the worst scenario was applied, a 62.0% cure rate (31/50) was obtained. CONCLUSIONS: A 12-month regimen with a minimum of four anti-tuberculosis agents at full dose, essentially selected on drug sensitivity testing, could be an alternative option for the treatment of drug-resistant pulmonary tuberculosis.

Cooking with biomass stoves and tuberculosis: a case control study.

OBJECTIVE: To search for an association between tuberculosis and use of biomass stoves found recently in a cross sectional study. DESIGN: In a case-control study based in a chest referral hospital, the cases were 288 patients with active smear-positive or culture-positive tuberculosis, and the controls were 545 patients with ear nose and throat ailments with no evidence of chest disease studied at the same time as the cases. Exposure to present or previous biomass smoke by history of cooking with traditional wood stoves was assessed by positive or negative response. RESULTS: Exposure to biomass smoke was significantly higher in cases than in controls. Crude odds ratios for tuberculosis and biomass smoke exposure were 5.2 (95%CI 3.1-8.9) for current exposure, 3.4 (95%CI 2.4-5.0) for past or present exposure and 1.8 (95%CI 1.1-3.0) for past exposure. The association was observed only for patients living in Metropolitan Mexico City and urban or suburban areas in the center of Mexico providing most cases and controls. For rural areas, the power of the study was low and the origin of the patients heterogeneous. Odds ratio for Mexico City Metropolitan area and the center of Mexico was 2.4 (95%CI 1.04-5.6), adjusted for age, sex, level of education, crowding, smoking, socio-economic level, zone of residence and state of birth. In the same model smoking had an OR of 1.5 (95%CI 1.0-2.3) for tuberculosis. CONCLUSION: Our results support a causal role of current domestic biomass smoke exposure in tuberculosis.

Atypical radiological images of pulmonary tuberculosis in 192 diabetic patients: a comparative study.

SETTING: Comparative studies of pulmonary tuberculosis images in diabetics have yielded conflicting results. OBJECTIVE: To assess radiological images of pulmonary tuberculosis in a large population of diabetic patients. DESIGN: Radiographs from in-patients admitted with pulmonary tuberculosis and diabetes (TBDM group, n = 192) were reviewed and compared with a control group of patients with pulmonary tuberculosis alone (TB group, n = 130). RESULTS: Both groups had a similar evolution time of tuberculosis (approximately 2 years). Statistical differences were observed as follows: TBDM patients were older (51.3+/-0.9 vs. TB group 44.9+/-1.8 years, mean +/- SEM), and had a decreased frequency of upper (17% vs. 56%), and an increased frequency of lower (19% vs. 7%) and upper + lower (64% vs. 36%) lung field lesions. More TBDM patients developed cavitations (82% vs. 59%) more often in the lower lung fields (29% vs. 3%). More multiple cavities were seen in TBDM patients (25% vs. 2%). TBDM group had a lower total leukocyte count (8836.7+/-219.5 vs. 10013.1+/-345.2 cells/mm3), mainly due to a lower number of non-lymphocyte cells (6815.8+/-221.8 vs. 8095.7+/-321.9 cells/mm3). Multiple logistic regression showed that being a diabetic patient was the most important factor determining lower lung field lesions and cavities. CONCLUSIONS: This study in a large number of diabetics with pulmonary tuberculosis confirmed that their chest X-ray images significantly depart from the typical presentation. Clinicians must keep this in mind to avoid misdiagnosis.

Progressive age-related changes in pulmonary tuberculosis images and the effect of diabetes.

Atypical radiologic images of pulmonary tuberculosis are common in elderly and in diabetic patients. To investigate the relationship of chest radiographic findings of tuberculosis to age in diabetic and nondiabetic patients, we compared the chest radiographic findings of 192 inpatients with pulmonary tuberculosis and diabetes with those of 130 patients with pulmonary tuberculosis alone. The proportion of patients with lower lung field lesions progressively increased with age (r(S) = 0.89, p < 0.01), whereas the frequency of cavitation steadily decreased with age (r(S) = -0.79, p < 0.05). In diabetic patients, a high frequency of lower lung lesions and cavitation was observed in all age groups. We speculated that, in older patients and in diabetics, the increased alveolar oxygen pressure in the lower lobes favors development of lower lobe disease in these groups.