National Registry of Interstitial Lung Disease from Pakistan.

Introduction Interstitial lung disease (ILD) is a heterogeneous group of over 200 parenchymal lung diseases with a myriad of etiologies. Interstitial lung disease registries from around the world show varying prevalence and incidence of these diseases. The aim of this study was to determine the epidemiology and characteristics of ILD in Pakistan. Methods This web-based registry, which is the first multicenter registry of ILD from Pakistan, recruited patients from 10 centers of five major cities between January 2016 and March 2019. Results A total of 744 patients were enrolled in the registry. The five most frequent ILDs were idiopathic pulmonary fibrosis (IPF) 34.4%, hypersensitivity pneumonitis (HP) - 17.7%, idiopathic nonspecific interstitial pneumonitis (iNSIP) - 16.8%, connective tissue disease-associated ILD (CTD-ILD) - 16.3%, and sarcoidosis - 9.1%. Conclusion Idiopathic pulmonary fibrosis is the most prevalent ILD in Pakistan, followed by HP and iNSIP. An ongoing prospective registry with longitudinal follow-up will help us further elaborate on the clinical characteristics, treatment, and survival outcome of patients with ILD.

Diagnostic Accuracy of Xpert MTB/RIF in Sputum Smear-Negative Pulmonary Tuberculosis.

Introduction Tuberculosis is a major health problem in Pakistan. The prevalence of pulmonary as well as extrapulmonary tuberculosis is quite high. Tuberculin skin test, radiological imaging, and sputum smear microscopy have limitations in the diagnosis of tuberculosis. Xpert MTB/RIF was recently approved for the diagnosis of pulmonary tuberculosis and has shown promising results. The aim of this study was to determine the diagnostic accuracy of Xpert MTB/RIF in sputum smear-negative pulmonary tuberculosis using acid-fast bacilli (AFB) culture as the gold standard. Materials and methods This cross-sectional study was conducted at Iqbal Yad Chest Clinic and Nazimabad Chest Clinic of Ojha Institute of Chest Diseases, Dow University of Health Sciences. Patients of either gender aged 18-65 years suspected to have pulmonary tuberculosis with at least two sputum samples negative for AFB underwent Xpert MTB/RIF testing. Early morning sputum samples were obtained and sent for AFB smear microscopy, Xpert testing and also for culture analysis. Results Mean age of the patients was 37.48 ±17.49 years. There were 84 (37.3%) females and 141 (62.7%) males. Positive findings on Xpert MTB/RIF were found in 147 (65.3%) patients whereas AFB culture showed positive findings in 174 (77.3%) patients. Sensitivity, specificity, positive predicted value, negative predicted value and overall diagnostic accuracy of Xpert MTB/RIF was found to be 84.48%, 100%, 100%, 65.38%, and 88%, respectively. Conclusion Xpert MTB/RIF has high sensitivity, specificity, and diagnostic accuracy in diagnosis of sputum smear-negative cases of pulmonary tuberculosis.

Differential Early Secreted Antigen Target (ESAT) 6 kDa-induced IFN-γ and SOCS1 expression distinguishes latent and active tuberculosis.

INTRODUCTION: Expression of Suppressor of cytokine signaling (SOCS)-1 molecules is increased in patients with tuberculosis (TB). Early Secreted Antigen Target (ESAT)-6 kDa - induced IFN-γ responses indicate Mycobacterium tuberculosis infection. The effect of ESAT6- stimulation on SOCS1 in the host is not known. METHODOLOGY: Healthy asymptomatic controls had a negative (n = 16) or a positive ( n = 13) tuberculin skin test (TST). ESAT6-induced IFN-γ responses classified these controls as positive (EC ESAT6 IFN-γ (+), n = 5) or negative (EC ESAT6 IFN-γ (-), n = 24) responders. Patients had pulmonary (n = 21) or extra-pulmonary (n = 30) tuberculosis. Peripheral blood cells were stimulated with ESAT6 and mRNA expression of IFN-γ and SOCS1 was determined. RESULTS: ESAT6-induced IFN-γ expression was raised in EC ESAT6 IFN-γ (+) as compared with EC ESAT6 IFN-γ (-), p = 0.019. ESAT6-induced SOCS1 mRNA expression was increased in both pulmonary TB and extra-pulmonary TB patients as compared with both EC groups. ESAT6-induced IFN-γ/SOCS1 mRNA expression ratio was decreased in TB patients as compared with both EC groups. CONCLUSION: M. tuberculosis infection induces increased ESAT6-induced IFN-γ responses in both latent and active TB. Our data shows down-regulation of IFN-γ / SOCS1 expression to be induced only in active TB cases, distinguishing them from healthy individuals likely to have latent TB. A decreasing IFN-γ /SOCS1 ratio may leads to reduced Th1 immunity which contributes to inability of the host to control clinical disease.

Six-minute walk test performance in healthy adult Pakistani volunteers.

OBJECTIVE: 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. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Two medical institutes of Karachi, from January to May 2011. METHODOLOGY: Subjects between 15 and 65 years were prospectively enrolled after screening. A standardized 6MWT was administered. SpO2, HR, BP and dyspnoea scores were determined pre- and post-test. RESULTS: 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*1) - (1.90*age in years) + (1.95*height in cms) 6MWD (m) for women = 164.08 - (1.90*age in years) + (1.95*height in cms). CONCLUSION: 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 naïve to the test when employing standardized protocol.

A randomized, double-blind, placebo-controlled trial of oral montelukast in acute asthma exacerbation.

BACKGROUND: Leukotriene receptor antagonists (LTRAs) are well established in the management of outpatient asthma. However, there is very little information as to their role in acute asthma exacerbations. We hypothesized that LTRAs may accelerate lung function recovery when given in an acute exacerbation. METHODS: A randomized, double blind, placebo-controlled trial was conducted at the Aga Khan University Hospital to assess the efficacy of oral montelukast on patients of 16 years of age and above who were hospitalized with acute asthma exacerbation. The patients were given either montelukast or placebo along with standard therapy throughout the hospital stay for acute asthma. Improvements in lung function and duration of hospital stay were monitored. RESULTS: 100 patients were randomized; their mean age was 52 years (SD +/- 18.50). The majority were females (79%) and non-smokers (89%). The mean hospital stay was 3.70 ± 1.93 days with 80% of patients discharged in 3 days. There was no significant difference in clinical symptoms, PEF over the course of hospital stay (p = 0.20 at day 2 and p = 0.47 at day 3) and discharge (p = 0.15), FEV1 at discharge (p = 0.29) or length of hospital stay (p = 0.90) between the two groups. No serious adverse effects were noted during the course of the study. CONCLUSION: Our study suggests that there is no benefit of addition of oral montelukast over conventional treatment in the management of acute asthma attack. TRIAL REGISTRATION NUMBER: 375-Med/ERC-04.

Vitamin D accelerates clinical recovery from tuberculosis: results of the SUCCINCT Study [Supplementary Cholecalciferol in recovery from tuberculosis]. A randomized, placebo-controlled, clinical trial of vitamin D supplementation in patients with pulmonary tuberculosis'.

BACKGROUND: Vitamin D enhances host protective immune responses to Mycobacterium tuberculosis by suppressing Interferon-gamma (IFN-g) and reducing disease associated inflammation in the host. The objectives of this study were to determine whether vitamin D supplementation to patients with tuberculosis (TB) could influence recovery. METHODS: Two hundred and fifty nine patients with pulmonary TB were randomized to receive either 600,000 IU of Intramuscular vitamin D3 or placebo for 2 doses. Assessments were performed at 4, 8 and 12 weeks. Early secreted and T cell activated 6 kDa (ESAT6) and Mycobacterium tuberculosis sonicate (MTBs) antigen induced whole blood stimulated IFN-g responses were measured at 0 and 12 weeks. Statistical comparisons between outcome variables at 0 and 12 weeks were performed using Student's t-test and Chi2 tests. RESULTS: After 12 weeks, the vitamin D supplemented arm demonstrated significantly greater mean weight gain (kg)+3.75, (3.16-4.34) versus+2.61 (95% CI 1.99-3.23) p 0.009 and lesser residual disease by chest radiograph; number of zones involved 1.35 v/s 1.82 p 0.004 (95% CI 0.15, 0.79) and 50% or greater reduction in cavity size 106 (89.8%) v/s 111 (94.8%), p 0.035. Vitamin D supplementation led to significant increase in MTBs-induced IFN-g secretion in patients with baseline 'Deficient' 25-hydroxyvitamin D serum levels (p 0.021). CONCLUSIONS: Supplementation with high doses of vitamin D accelerated clinical, radiographic improvement in all TB patients and increased host immune activation in patients with baseline 'Deficient' serum vitamin D levels. These results suggest a therapeutic role for vitamin D in the treatment of TB. TRIAL REGISTRATION: ClinicalTrials.gov; No. NCT01130311; URL: clinicaltrials.gov.

Expression of M. tuberculosis-induced suppressor of cytokine signaling (SOCS) 1, SOCS3, FoxP3 and secretion of IL-6 associates with differing clinical severity of tuberculosis.

BACKGROUND: Appropriate immune activation of T cells and macrophages is central for the control of Mycobacterium tuberculosis infections. IFN-γ stimulated responses are lowered in tuberculosis (TB), while expression of Suppressor of Cytokine Signaling (SOCS) molecules - 1 and 3 and CD4+CD25+FoxP3+T regulatory cells is increased. Here we investigated the association of these molecules in regard to clinical severity of TB. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from patients with pulmonary TB (PTB, n = 33), extra-pulmonary TB (ETB, n = 33) and healthy endemic controls (EC, n = 15). Cases were classified as moderately advanced or far advanced PTB, and less severe or severe disseminated ETB. M. tuberculosis -stimulated IFN-γ, SOCS1, SOCS3 and FoxP3 gene expression and secretion of Th1 and Th2 cytokines was measured. Statistical analysis was performed using Mann-Whitney U, Wilcoxon Rank and Kruskal Wallis non-parametric tests. RESULTS: In un-stimulated PBMCs, IL-6 (p = 0.018) and IL-10 (p = 0.013) secretion levels were increased in PTB while IL-10 was also increased in ETB (p = 0.003), all in comparison with EC. M. tuberculosis-stimulated IL-6 (p = 0.003) was lowered in ETB as compared with EC. SOCS1 mRNA expression in M. tuberculosis stimulated PBMCs levels in moderately advanced PTB (p = 0.022), far advanced (p = 0.014) PTB, and severe ETB (p = 0.009) were raised as compared with EC. On the other hand, SOCS1 mRNA titers were reduced in less severe ETB, in comparison with severe ETB (p = 0.027) and far advanced PTB (p = 0.016). SOCS3 mRNA accumulation was reduced in far advanced PTB (p = 0.007) and FoxP3 mRNA expression was increased in less severe ETB as compared with EC (p = 0.017). CONCLUSIONS: The lowered SOCS1 mRNA levels in patients with less severe extra-pulmonary TB as compared to those with more severe ETB and PTB may lead to elevated IFN-γ pathway gene expression in the latter group. As localized ETB has shown to be associated with more effective Th1 immunity and adaptive responses, this suggests a role for SOCS1 in determining disease outcome in extra-pulmonary TB.

Measurement of ESAT6-induced IFNγ responses adjunct with CXCL9 increases the rate of diagnosis of active tuberculosis in an endemic region.

Due to difficulties in direct diagnosis of Mycobacterium tuberculosis infection where site-specific specimens are not available, indirect methods of testing for infection are required. M. tuberculosis early secreted antigen target-6 (ESAT6) induced IFN-γ responses are specific, but do not differentiate between latent and active TB. The use of adjunct biomarkers for TB diagnosis has been proposed, such as the chemokines: CXCL9, CXCL10 and CCL2. ESAT6-induced IFN-γ CXCL9, CXCL10 and CCL2 was measured in whole blood cell supernatants of patients with pulmonary tuberculosis (PTB, n=36) and extrapulmonary TB (ETB, n=31) and compared with healthy endemic controls (EC, n=33). ESAT6-induced IFN-γ responses were positive in 32% of TB cases as compared with 15% of EC cases (p=0.048). ESAT6-induced CXCL9 responses were positive in 42% of TB cases and 15% of EC cases (p=0.006). ESAT6-induced-CXCL10 and -CCL2 responses did not discriminate between TB and EC groups. Measurement of IFN-γ or CXCL9 together diagnosed TB (53%) cases and was significant as compared with EC (p=0.014) cases. IFN-γ and CXCL10 together did not increase the number of TB cases diagnosed. Within TB groups, ESAT6-IFN-γ/CXCL9-based detection increased to 53% in PTB (p=0.031) and 54% in ETB (p=0.021), with comparable diagnosis in less severe extrapulmonary TB (L-ETB, 55%) and severe disseminated extrapulmonary TB (D-ETB, 50%). Given that 47% of TB cases remained undetected, this study shown that ESAT6-induced IFNγ and CXCL9 can support diagnosis, but must be supported by clinical correlation and other relevant investigations.

BCG vaccination is associated with decreased severity of tuberculosis in Pakistan.

Vaccination with Bacille Calmette-Guérin (BCG) is given at birth to protect against tuberculosis (TB) in Pakistan. The country ranks 6th amongst high-burden countries worldwide and has an incidence of 231/100,000 pyopulation. This was a cross-sectional multi-center hospital-based study. TB patients (n=218) with pulmonary (PTB, n=120) or extrapulmonary (ETB, 98) were recruited, and the presence of a BCG vaccination scar was documented. Cases were further classified into minimal, moderate and advanced PTB or less severe (L-ETB) or severe disseminated (D-ETB) disease. The association of age, gender and severity of TB infections with BCG vaccination of the individual TB cases was investigated. No difference was found of the BCG vaccination status of PTB and ETB cases, or in relation to age or gender. Patients under 29years of age comprised the largest group. There were more females with ETB than PTB. The largest group within ETB comprised those with tuberculous lymphadenitis (LNTB, 39%). A significantly greater number of LNTB cases had received BCG vaccinations than had those with pleural (unilateral) TB (p=0.004), and tuberculous meningitis (p=0.027) groups. Also, there were more immunized patients with pulmonary as compared with pleural disease (p=0.001). LNTB represents localized granulomatous disease and the observation of higher vaccination rates in this group suggests that BCG has protected against more severe forms of TB in this high-burden region.

Drug resistance pattern in multidrug resistance pulmonary tuberculosis patients.

OBJECTIVE: 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. STUDY DESIGN: An observational study. PLACE AND DURATION OF STUDY: The multidrug resistant tuberculosis (MDR-TB) ward of Ojha Institute of Chest Diseases (OICD), Karachi, from 1996 to 2006. METHODOLOGY: 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. RESULTS: 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. CONCLUSION: 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.

Variables predictive of outcome in patients with acute hypercapneic respiratory failure treated with noninvasive ventilation.

OBJECTIVE: To assess results with NIV in acute hypercapneic respiratory failure and to identify outcome predictors. METHODS: This was a retrospective observational study on consecutive patients presenting with acute type II respiratory failure and meeting criteria for NIV use over a 5 year period. Patients presenting with haemodynamic instability, inability to protect their airway, malignant arrhythmias and recent oesophageal surgery were excluded. Univariate and Multivariate regression analysis was used to determine the impact on survival. A p value of < 0.05 was considered statistically significant. Software used was SPSS 14. RESULTS: Total numbers of patients included were 119; 52.9% were males. Mean age was 63.4 +/- 11.9 years. Overall Survival to discharge rate was 76.5%, intubation rate was 12.6% and mean length of stay was 11.4 +/- 10.9 days. Statistically significant improvements were observed in the pH and PaCO2 at 24 hours and 48 hours compared to baseline (7.28 v/s 7.37, p < 0.001; 74.2 v/s 65, p < 0.001). On multivariate regression analysis, sepsis at admission predicted mortality (adjusted Odds ratio 26.4; 95% CI 2.3, 304, p < 0.009). A serum HCO3 > 35 Meq/L (adjusted Odds ratio 0.9; 95% CI 0.83, 0.98, p < 0.015) identified those less at risk for intubation. CONCLUSION: NIV was found to be both safe and effective in the management of acute hypercapneic respiratory failure. Sepsis and serum HCO3 at admission identified patients having poor outcomes.

Treatment outcome of multi-drug resistant tuberculosis in a tertiary care hospital in Karachi.

OBJECTIVE: To assess the outcomes of pulmonary multidrug-resistant tuberculosis (MDR-TB) patients treated at Ojha Institute of Chest Diseases (OICD), a reference hospital for TB in Karachi, Pakistan. METHODS: Clinical study for the period 1996-2006, with follow-up until June 2007 was performed. All the culture and sensitivity proven cases of MDR pulmonary TB were initially admitted for 3-6 months till the sputum converted negative. Treatment regimen was decided on individual basis, and included 4-6 drugs. Supervised treatment was given to all patients during the hospitalization. After discharge from the hospital, patients were followed at monthly interval at the outpatient department of OICD for 18 months total. RESULTS: Five hundred and seventy nine adult patients (59.93% male) with mean age of 32.44 +/- 12.63 years were studied. All patients had a history of treatment with first line anti-tuberculosis drugs. Treatment was successful in 227 (39.2%). The mortality rate was 27(4.6%) during hospitalization. During admission 83(14.3%) left treatment and 239 (41.2%) were lost to follow-up during treatment. Treatment failure was observed in three patients. CONCLUSION: The treatment success rate in this study is satisfactory but high default rate is a challenge in the management of MDR tuberculosis.

Magnitude of initial default in pulmonary tuberculosis.

OBJECTIVE: To assess the magnitude and reasons of initial default in pulmonary tuberculosis patients, diagnosed at Nazimabad Chest Clinic, Karachi. METHODS: This prospective study was conducted over five months from 1st December 2007 to 30th April 2008. Suspected tuberculosis patients were prescribed sputum AFB (Acid Fast Bacilli) smears for three samples. This study included the smear positive patients who did not collect their report and were therefore defaulters for initiation of anti-tuberculosis treatment. These patients were contacted on phone, reasons of defaults were enquired and they were offered free treatment. RESULTS: In the study period, out of 869 tuberculosis suspects, 224 were diagnosed as smear positive pulmonary tuberculosis. Of these 224, one hundred and sixty-two got themselves registered for treatment. The remaining 62/224 (27.67%) were initial defaulters. On telephonic contact, 55 (88.70%) were traceable while 07/62 (11.29%) were Untraceable-defaulters. Twenty-four patients (38.70%) reported to the clinic and were registered for treatment. The most common reason for default was 'dissatisfaction with services at the clinic'. CONCLUSION: A high initial default for initiating Anti-Tuberculosis Therapy is a serious issue that needs to be addressed.

Primary drug resistance against Mycobacterium tuberculosis in Karachi.

OBJECTIVE: To evaluate the primary drug resistance of new culture positive cases of pulmonary tuberculosis in Karachi. METHODS: All new suspected pulmonary tuberculosis patients were recruited initially. They were instructed to produce three-sputum samples for smear examination and on one of the specimen's culture was applied. Bronchoscopy and bronchial wash was done in patients who were not expectorating. Bronchial wash was then applied for both smear and culture for Mycobacterium tuberculosis. RESULTS: Out of 79 cases recruited initially, 52 were able to produce sputum while bronchoscopy was performed in the remaining. AFB direct smear was positive in 32/52 sputum and 12/27 bronchial wash samples. Later, 02 sputums and 04 bronchial washes became culture positive which were initially smear negative. All cultures were of Mycobacterium tuberculosis species. These fifty culture positive cases were then included in the final analysis. Pyrazinamide was the most sensitive drug i.e. 49 isolates (98%). The resistance pattern is as follows: Streptomycin 13(26%), Isoniazid 08 (16%), Ethambutol 08 (16%), Rifampicin 04 (08%) and Pyrazinamide one (02%). Multi-Drug Resistant tuberculosis was observed in 02 (04%) patients. CONCLUSION: In this small study, the high prevalence of primary resistance against streptomycin, INH and Ethambutol raises an urgent need of a proper nationwide survey to evaluate the true picture of primary resistance.

New drugs in resistant tuberculosis.

The World Health Organization estimates that up to 50 million persons worldwide may be infected with drug resistant strains of TB. The fatality rate of MDR-TB is 20-80%. Drug resistant tuberculosis cases are on the rise in Pakistan. The reasons for this menace are multiple including improper prescription, compliance and over the counter sale of anti-TB drugs. The treatment cost of drug-resistant TB is high, both to the individual patient and society. This article is written to create awareness about the available second line drugs and those in the pipeline. Considering the fact that resistant tuberculosis is difficult to manage, it is suggested that these drugs should only be used after consultation with a physician experienced in the treatment of drug resistant TB. The most frequent mistake made by treating physicians is addition of one drug in the failing regimen. At present, 27 potential anti-TB drugs are at various stages of development. The aim is that by 2010 at least one of these molecules completes the journey and should come in the market.