Utility of Xpert MTB/RIF Assay for Diagnosis of Pediatric Tuberculosis Under Programmatic Conditions in India.

Tuberculosis (TB) diagnosis in children still remains a challenge in developing countries. We analyze the performance of Xpert MTB/RIF assay for the diagnosis of pediatric TB under programmatic conditions. We retrospectively analyzed the performance of Xpert MTB/RIF assay from February 2016 to March 2018. A total 2678 samples from TB suspects below 14 years were received in the laboratory and were frontline tested by Xpert MTB/RIF assay according to the manufacturer's instructions. If sample was sufficient, the smear microscopy and culture were performed as per standard World Health Organization's guidelines. The smears and cultures were performed in 2178 and 588 samples, respectively. Among 2678 samples, 68 were rejected, Xpert MTB/RIF assay was positive in 357/2610 (13.6%) cases, while the smear was positive in 81/2178 (3.3%) cases. The sensitivity of smear and Xpert MTB/RIF when compared with culture was 24.6% (14.1-37.8%) and 81% (68.6-90.1%), respectively. The diagnostic accuracy of Xpert MTB/RIF and smear was 97.1% and 92.2%, respectively. Thirty samples (8.5%) were detected as rifampicin resistance by Xpert MTB/RIF assay. The Xpert MTB/RIF increased the detection rate up to fourfold when compared with smear microscopy. Xpert MTB/RIF assay is the most rapid, sensitive, and specific method for microbiological confirmation and rifampicin resistance detection in pediatric tuberculosis.

Second-line Drug Resistance Characterization in Mycobacterium tuberculosis by Genotype MTBDRsl Assay.

Tuberculosis (TB) remains a main hurdle for national programs due to increase in drug resistance to antitubercular drugs. World Health Organization (WHO)-endorsed Line Probe Assay, Genotype MTBDRsl Ver 2.0, gives opportunity for rapid diagnosis and molecular characterization of different mutations in drug targets of fluoroquinolone (FQ) and second-line injectable drugs (SLID). We, retrospectively, analyzed the data of Genotype MTBDRsl Ver 2.0 from January 2018 to June 2018. A total of 863 isolates of Mycobacterium tuberculosis, 687 rifampicin resistant and 176 isoniazid resistant only, were screened for drug resistance in FQ and SLID. All the isolates were tested for Genotype MTBDRsl Ver 2.0 according to the manufacturer's instructions. The FQ and SLID resistance were detected in 295 (34.2%) and 70 (8.1%) isolates, respectively. Among newly diagnosed and follow-up rifampicin-resistant TB (RR TB) patients, the FQ resistance was 25.8% and 44.5%, respectively. The most common mutation (42.7%) in FQ-resistant isolates was MUT3C in gyrA gene. Both SLID and FQ resistance were detected in 59 (6.8%) RR TB isolates. The mono SLID resistance was detected in 12 (1.7%) isolates of RR TB. Genotype MTBDRsl Ver 2.0 assay is a rapid and important tool for the diagnosis and molecular characterization of second-line drug resistance under programmatic conditions.

Impact of introducing light-emitting diode fluorescence microscopy services for diagnosis of pulmonary tuberculosis under Revised National Tuberculosis Control Program India.

CONTEXT: Light-emitting diode fluorescence microscopy (LED-FM) has been recommended by the WHO and the Government of India over the conventional bright-field microscopy using Ziehl-Neelsen (ZN) staining for the diagnosis of sputum smear-positive tuberculosis (TB) suspects. AIM: The aim of this study was to assess the effectiveness of LED-FM in detecting TB cases. SETTING AND DESIGN: This retrospective cohort study was carried out in December 2016 using secondary data of the years 2011-2012 from designated microscopy centers (DMCs) at Chandigarh, India. METHODOLOGY: Two peripheral DMCs where conventional ZN microscopy was used were taken as controls comparable to two peripheral DMCs which used LED-FM services in programmatic settings. The record of all suspected TB patients who underwent sputum smear examination pre- and post-LED-FM introduction was compared for measuring smear-positive cases, conformational grading, and time taken to read per slide examined. Chi-square was applied to access the statistical significance. RESULTS: Out of total 8850 cases registered after the inception of LED-FM microscopy services, case detection rate was 13.3%, with significant decrease in case detection rate at tertiary level DMCs, there was significant increase in case detection rate at peripheral DMCs operating with LED-FM in contrast to ZN microscopy which was used previously. Scanty grade smear increased significantly by 9.0%. The time taken per slide examination decreased by 57.1% (from 7 min on an average to 3 min on an average) after LED-FM was used. CONCLUSION: LED-FM is easy to use, takes lesser time to examine slides, and has longer self-life. It also eases laboatory technician's task in reporting scanty grade positives which use to be challenging previously. The results of this study provide enough evidences to scale up the installation process and usage of LED-FM at DMCs for TB diagnosis in Indian settings.

Genetic Characterization of Second-Line Drug-Resistant and Extensively Drug-Resistant Mycobacterium tuberculosis from the Northern Region of India.

Rapid detection of drug resistance in Mycobacterium tuberculosis is important for the successful treatment of tuberculosis. Fluoroquinolone and aminoglycoside resistance detection by molecular methods becomes more complex due to cross resistance among them. Thus, we aimed to determine cross-resistance and mutations in resistance genes for these drugs. A total of 336 multidrug-resistant tuberculosis (MDR-TB) cases received in Mycobacteriology laboratory were screened for phenotypic drug sensitivity testing for second-line drugs, i.e., ofloxacin, amikacin, kanamycin, and capreomycin. Molecular characterization of resistance was done by DNA sequencing of gyrA gene for fluoroquinolones (FQ), and multiplex allele-specific polymerase chain reaction (PCR) and PCR restriction fragment length polymorphism (RFLP) of rrs gene for aminoglycosides. Of 336 MDR-TB isolates, 12 were extensively drug-resistant tuberculosis and 219 were sensitive to all the drugs tested. Ofloxacin, amikacin, kanamycin, and capreomycin resistance was detected in 101 (30.1%), 23 (6.8%), 27 (8.1%), and 19 (5.6%) cases, respectively. Eight different mutations were detected in gyrA gene in ofloxacin-resistant isolates and A1401G nucleotide change in rrs gene were seen in 55.6% (15/27), 65.2% (15/23), and 68.4% (13/29) for kanamycin-, amikacin-, and capreomycin-resistant isolates, respectively. Information on second-line drug resistance-associated mutations could potentially be used for development of newer rapid diagnostic tests.

Prevalence of Diabetes Mellitus and its Predictors among Tuberculosis Patients Currently on Treatment.

BACKGROUND: Tuberculosis (TB) and diabetes are the world's leading public health issues. They are the cause of morbidity, mortality, and pose a burden on the healthcare system. AIMS AND OBJECTIVES: The aim and objective of this study were to study the prevalence of diabetes and its predictors among TB patients currently on treatment. The secondary objective was to examine the self-reported blood glucose monitoring and antidiabetic drug adherence practice among diabetic TB patients. METHODOLOGY: This cross-sectional study was undertaken on 275 TB cases enrolled from selected designated microscopy centers. Self-reported information on diabetes, tobacco usage, and family history of TB was collected by trained investigators. In addition, for diabetic tubercular patients, the study investigators inquired about the type of treatment taken (allopathic/traditional), frequency of getting blood sugar tested, and daily drug adherence. For comparison between the "diabetes TB comorbidity" and "TB only group," Chi-square test of significance was used, and odds ratios were reported. Data were analyzed using Epi Info software (CDC Atlanta). RESULTS: The prevalence of diabetes among TB patients was found to be 13.1% (known diabetics -9.1% and new diabetics -4.0%). There were 25.5% of current/former smokers (70/275) and 13.1% of current/former smokeless tobacco users (36/275). In logistic regression analysis, age 50 years and above emerged as a significant predictor for diabetes TB comorbidity (adjusted odds ratio = 9.8 [4.3-22.3]). CONCLUSION: Diabetes is prevalent comorbidity in TB patients. Age more than 50 years significantly increases the odds of this twin morbidity.