Evaluation of particle agglutination test for detection of HIV-I antibodies.

A commercially available particle agglutination test (PA) was evaluated for its specificity and sensitivity as compared to ELISA currently used in our laboratory to detect HIV-I antibodies. A total of 463 sera from blood donors and clinical referrals were screened by PA, 45 were found to be positive (9.7%). Out of 463, 258 sera were simultaneously screened by ELISA; 28 were found to be positive (10.8%). Twelve samples showing positive results by both ELISA & PA were tested by Western blot and were confirmed to be positive. We found sensitivity of PA as compared to ELISA as 100% and specificity to be 88.44%. Readings of PA taken at 2 hrs should be reconfirmed at 24 hrs as it eliminates a number of false positives. Overall, we feel PA is fairly comparable with ELISA. It can be used in the set up where equipment and trained personnel for ELISA are not available for primary screening purposes.

Differential identification of Mycobacterium tuberculosis from various clinical specimens from Sassoon General Hospital, Pune.

A total of 619 clinical specimens from cases of pulmonary and extrapulmonary tuberculosis were processed by smear, culture and biochemical tests. Acid fast bacilli could be demonstrated in 93 samples (15.02%) by Z.N. staining method. Culture yielded positive growth in 95 samples (15.35%) M. tuberculosis human type was the most predominient pathogen obtained from 82 cultures (13.40%) M tuberculosis bovine type was isolated from 2 cases of ascitic fluids (0.32%). Atypical Mycobacteria were isolated from 11 samples (1.73%). 5 turned out to be M. scrofulacium, 4 were M. Kansasii, 1 was M. phlei and 1 was M. smegmatis.

Anaerobic bacteria in brain abscess, a review; observation of 18 consecutive cases.

The aerobic and anaerobic bacterial flora of 18 consecutive cases of brain abscesses were studied. Two cases were sterile. In five cases there was a single bacterial isolate. In five cases there was a single bacterial isolate the organism being Staphylococcus aureus in two cases, Bacteroides fragilis in two cases and Peptostreptococcus anaerobius in one case. In the remaining eleven cases, more than one organism was isolated. A combination of anaerobe with an aerobe was observed in five cases and infections with more than one anaerobe in as many as six cases. Anaerobic organisms are the important pathogens in brain abscess and occurrence of infections by more than one organism is a common factor.

Raising monospecific antibodies by use of protein components prestained with Remazol Brilliant Blue and separated by disc electrophoresis on polyacrylamide gel.

We have reported (Clin Chem 29: 42-44, 1983) that prestaining with Remazol Brilliant Blue permits direct visualization of serum components on disc electrophoresis, and apparently purifies the proteins well. Here we have cut out the bands corresponding to the prestained albumin and transferrin after disc electrophoresis of normal human serum proteins, eluted some individual proteins into saline, and assessed their purity by immunoelectrophoresis and two-dimensional crossed immunoelectrophoresis against polyvalent antihuman serum. These two techniques indicated purity of these antigens. We inoculated rabbits with the eluates containing the pure antigens, and tested the resulting antibodies for monospecificity by immunoelectrophoresis, rocket electrophoresis, and single radial immunodiffusion. From the results we conclude that the antibodies raised against each component were monospecific, and that this is a simple, economical, rapid, and reliable method for obtaining a pure fraction of serum protein for use as an antigen.