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Background: Monitoring of hepatitis B virus (HBV) viral load has become an essential phase in the treatment of HBV. There are many commercial assays available for HBV viral load quantification. In this study, we have evaluated the performance characteristics of Amplisure® HBV Kit in comparison with the Qiagen artus HBV QS-RGQ kit for HBV DNA quantitation. Methods: Comparison of 2 methods was carried out on 200 clinical samples, 150 HBV DNA positive and 50 HBV DNA negative, by a reference method. Results obtained with Amplisure® HBV Kit (Amplisure HBV) were compared using the Qiagen artus HBV QS-RGQ assay results as the comparator method. Result: The overall performance of the Amplisure HBV compared with the comparator method shows positive and negative clinical agreement of 100 and 76%, respectively. Among the 12 qualitative discrepant samples, all positive with Amplisure HBV were sequenced and 10 were below comparator method’s LOD. For 5 weak positives (−0.22 to 0.98 log IU/mL), the sequencing failed. The 7 other positives (0.48 to 1.89 log IU/mL) were confirmed positive by sequencing. Quantitative comparison gave an r2 of 0.967 with a mean log difference of 0.09 log10 IU/mL. Conclusion: This study shows that Amplisure® HBV Quantitative Kit shows comparable performance with artus HBV QS-RGQ assays and can be useful in management and therapeutic monitoring of HBV in a clinical practice.

A total of 400 serum samples collected from patients, clinically suspected of leptospirosis, were evaluated for antibodies by LEPTO dipstick and microscopic agglutination test (MAT). Twenty of these patients (5%) had serological evidence of leptospirosis. Leptospira interrogans serovars Autumnalis and Icterohaemorrhagiae, Canicola and Javanica were serogroups recorded serologically. Fever and jaundice were the most common clinical presentations. Male preponderance was seen in the leptospirosis cases. Outdoor activities, agricultural activities, contact with animals were significantly associated with seropositivity for Leptospira. This study highlights that leptospirosis is a significant health problem in northern India, though grossly under reported due to the absence of routine laboratory diagnostic facilities for this disease.

Antistreptolysin O (ASO) levels vary with age group of the study population and geographical locations. The present study was undertaken to determine the upper limit of normal of ASO in 200 normal children of 5-15 years of age with no history of recent sore throat infection. The standard tube dilution method (WHO) was used for estimating ASO titers. It was found that 239 IU was the upper limit of normal in the study population, which can be considered as the baseline ASO titer. This can provide useful guidelines for physicians in the interpretation of elevated ASO titers in cases of suspected acute rheumatic fever.

Sputum smear microscopy is the most efficient and rapid technique for detection of acid-fast bacilli (AFB). Fluorochrome method of staining is preferred for Mycobacteria in the overburdened laboratories as the fluorescing bacilli are more readily detected than the fuchsin stained bacilli in shorter period of time. A total of 300 sputum samples obtained from suspected cases of Tuberculosis were collected and were subjected to staining by rhodamine auramine at 37 degrees C and also at room temperature (conventional method). The smears were then blindly evaluated. Fifty-eight samples were positive by both methods and 5 were positive at 37 degrees C only. Staining at 37 degrees C increased the smear positivity by 8.6% over conventional staining at room temperature. No smears were positive only with staining at room temperature alone. Out of 58 smears positive by both methods, 25 had equal number of AFB in both smears, 22 had more AFB in smear stained at 37 degrees C and 11 had greater number of AFB in smears stained at room temperature. Our study, therefore, indicates that rhodamine auramine staining at 37 degrees C is superior to conventional auramine method at room temperature for detecting AFB in sputum smears.

Background & Objectives: Multidrug resistant (MDR) tuberculosis (TB) is a problem of increasing importance in the world due to limited treatment options. Resistance to rifampicin results from nucleotide changes in the gene encoding the beta subunit of the RNA polymerase (rpoB) of Mycobacterium tuberculosis. Rifampicin resistance is considered as a marker for MDR TB. The nature and frequency of mutations in the rpoB gene of rifampicin resistant clinical isolates vary considerably according to the geographical location and very little information is available on specific mutational patterns in India. This study was undertaken to detect and characterize the rpoB gene mutation associated with rifampicin resistance in M. tuberculosis by line probe assay., Methods: A total of 36 strains of M. tuberculosis were analysed by INNO-LiPA Rif TB and compared with the results of conventional susceptibility testing method. After PCR amplification of the region of RNA polymerase involved in rifampicin resistance, the amplified product was hybridized with a set of 10 oligonucleotides immobilized onto a membrane strip. From the pattern obtained, the presence or absence of rifampicin resistance in the M. tuberculosis strains was assessed., Results: It was found that the M. tuberculosis probe was 100 per cent specific; the most frequently observed mutation was His-526-Tyr in the rpoB gene; and correlation between the results of the LiPA and those obtained by the classical susceptibility testing was excellent (100%)., Interpretation & Conclusion: INNO LiPA was found to be a reliable, simple, rapid and informative tool for the early detection and characterization of rpoB mutation associated with rifampicin resistance in M. tuberculosis in the clinical laboratory setting and may constitute an important molecular method for the control of tuberculosis.