Tuberculosis in the tropics

Screening outcomes of household contacts of multidrug-resistant tuberculosis patients in Peshawar, Pakistan

OBJECTIVE

To assess the profile of TB/multidrug-resistant TB (MDR-TB) among household contacts of MDR-TB patients.

METHODS

Close contacts of MDR-TB patients were traced in the cross-sectional study. Different clinical, radiological and bacteriological were performed to rule out the evidence of TB/MDR-TB.

RESULTS

Between January 2012 and December 2012, a total of 200 index MDR-TB patients were initiated on MDR-TB treatment, out of which home visit and contacts screening were conducted for 154 index cases. Of 610 contacts who could be studied, 41 (17.4%) were diagnosed with MDR-TB and 10 (4.2%) had TB. The most common symptoms observed were cough, chest pain and fever.

CONCLUSIONS

The high incidence of MDR-TB among close contacts emphasize the need for effective contact screening programme of index MDR-TB cases in order to cut the chain of transmission of this disease.

Increased levels of both Th1 and Th2 cytokines in subjects with metabolic syndrome (CURES-103)

OBJECTIVE

Metabolic syndrome (MS) is a cluster of metabolic abnormalities associated with obesity, insulin resistance (IR), dyslipidemia, and hypertension in which inflammation plays an important role. Few studies have addressed the role played by T cell-derived cytokines in MS. The aim of the study was to look at the T-helper (Th) 1 (interleukin [IL]-12, IL-2, and interferon-γ [IFN-γ]) and Th2 (IL-4, IL-5, and IL-13) cytokines in MS in the high-risk Asian Indian population.

RESEARCH DESIGN AND METHODS

Study subjects were recruited from the Chennai Urban Rural Epidemiology Study. MS was defined using National Cholesterol Education Program-Adult Treatment Panel III criteria modified for waist according to World Health Organization Asia Pacific guidelines. Serum cytokine profile was determined by multiplex cytokine assay in subjects with (n = 21) and without (n = 33) MS.

RESULTS

Both Th1 and Th2 cytokines showed up-regulation in MS. IL-12 (5.40 pg/mL in MS vs. 3.24 pg/mL in non-MS; P < 0.01), IFN-γ (6.8 pg/mL in MS vs. 4.7 pg/mL in non-MS; P < 0.05), IL-4 (0.61 pg/mL in MS vs. 0.34 pg/mL in non-MS; P < 0.001), IL-5 (4.39 pg/mL in MS vs. 2.36 pg/mL in non-MS; P < 0.001), and IL-13 (3.42 pg in MS vs. 2.72 pg/mL in non-MS; P < 0.01) were significantly increased in subjects with MS compared with those without. Both Th1 and Th2 cytokines showed a significant association with fasting plasma glucose level even after adjusting for age and gender. The Th1 and Th2 cytokines also showed a negative association with adiponectin and a positive association with the homeostasis model of assessment of IR and high-sensitivity C-reactive protein.

CONCLUSIONS

Apart from pro-inflammatory cytokines, Th cytokines might play an important role in inflammation, IR, and MS.

Expanding tuberculosis case detection by screening household contacts

OBJECTIVES

Tuberculosis (TB) case detection remains low in many countries, compromising the efficacy of TB control efforts. Current global TB control policy emphasizes case finding through sputum smear microscopy for patients who self-report to primary health centers. Our objective was to assess the feasibility and yield of a simple active case finding strategy in a high incidence population in northern Lima, Peru.

METHODS

We implemented this pilot strategy in one health center's catchment area. Health workers visited household contacts of new TB case subjects to identify symptomatic individuals and collect sputum for screening. Neighboring households were screened in the same manner. Secondary analyses measured risk of TB by (1) sputum smear status of the index case subject, (2) compliance with testing, and (3) risk factors for disease detected through active contact tracing in contrast to self-report.

RESULTS

The TB prevalence detected through combined active and passive case finding among 1,094 household contacts was 0.91% (914 per 100,000), much higher than with passive case finding alone (0.18%; 183 per 100,000; p=0.02). Among 2,258 neighbors, the combined strategy detected a TB prevalence of 0.22% (221 per 100,000) in contrast to 0.08% (80 per 100,000) detected through passive case finding alone (p=0.25). Risk factors for being diagnosed through active case finding in contrast with self-report included age >55 years (odds ratio [OR]=5.5; 95% confidence interval [CI] 1.2, 22.8) and female gender (OR=3.9; 95% CI 0.99, 22.3).

CONCLUSIONS

Risk of active TB among symptomatic household contacts of active case subjects in this community is very high. Results suggest that contact tracing in such settings may be a powerful means of improving case detection rates for active TB disease.