Six-minute walk test performance in healthy adult Pakistani volunteers

To determine the six-minute walking distance [6MWD] for healthy Pakistanis, identify factors affecting 6MWD, compare published equations with the local data and derive an equation. Cross-sectional study. Two medical institutes of Karachi, from January to May 2011. Subjects between 15 and 65 years were prospectively enrolled after screening. A standardized 6MWT was administered. SpO[2], HR, BP and dyspnoea scores were determined pre- and post-test. Two hundred and eleven [71%] men and 85 [29%] women participated. Mean 6MWD was 469.88 +/- 101.24 m: men walked 502.35 +/- 92.21 m and women walked 389.28 +/- 74.29 m. On univariate analysis, gender, height, weight and age showed a significant relationship with the 6MWD. Gender and age were identified as independent factors in multiple regression analysis, and together explained 33% of the variance. The gender-specific prediction equations were: 6MWD [m] for men = 164.08 + [78.06 [asterisk] 1] - [1.90 [asterisk] age in years] + [1.95 [asterisk] height in cms] 6MWD [m] for women = 164.08 - [1.90 [asterisk] age in years] + [1.95 [asterisk] height in cms]. 6MWDs among the volunteer subjects were shorter than predicted by reference equations in literature. Height, gender and weight combined explained 33% of the variance. The moderate over-estimation of the 6MWD in Pakistani subject. The proposed equation gives predicted [mean] 6MWDs for adult Pakistani naive to the test when employing standardized protocol

Drug resistance pattern in multidrug resistance pulmonary tuberculosis patients

To evaluate the frequency of drug resistance profiles of multidrug resistant tuberculosis [MDR-TB] isolates of pulmonary tuberculosis patients, against both the first and the second line drugs. An observational study. The multidrug resistant tuberculosis [MDR-TB] ward of Ojha Institute of Chest Diseases, Karachi, from 1996 to 2006. Culture proven MDR-TB cases [resistant to both isoniazid and Rifampicin] were retrospectively reviewed. Susceptibility testing was performed at the clinical laboratory of the Aga Khan University. Sensitivity against both first and second line anti-tuberculosis drugs was done. Susceptibility testing was performed using Agar proportion method on enriched middle brook 7H10 medium [BBL] for Rifampicin, Isoniazid, Streptomycin, Ethambutol, Ethionamide, Capreomycin and Ciprofloxacin. Pyrazinamide sensitivity was carried out using the BACTEC 7H12 medium. During the study period MTB H37Rv was used as control. Out of total 577 patients, all were resistant to both Rifampicin and Isoniazid [INH]. 56.5% isolates were resistant to all five first line drugs. Resistances against other first line drugs was 76.60% for Pyrazinamide, 73% for Ethambutol and 68.11% for Streptomycin. Five hundred and ten [88%] cases were MDR plus resistant to one more first line drug. Forty [07%] isolates were MDR plus Quinolone-resistant. They were sensitive to Capreomycin but sensitivity against Amikacin and Kanamycin were not tested. There were high resistance rates in MDR-TB to remaining first line and second line drugs. Continuous monitoring of drug resistance pattern especially of MDR isolates and treatment in specialized centers is a crucial need for future TB control in Pakistan

Pulmonary alveolar microlithiasis

Pulmonary alveolar microlithiasis [PAM] is a rare disorder. It is characterized by accumulation of calcium phosphate [microlith] within the alveoli. Knowledge of this condition is important because radiologically it mimics miliary tuberculosis that can lead to the wrong treatment