Bacteriological study of pyogenic meningitis with special reference to latex agglutination.

Bacterial meningitis is an important and frequent devastating disease. The present study was carried out to determine the prevalence of pyogenic meningitis in our hospital in children and to find out the sensitivity of Gram stain, CRP and latex agglutination tests for the diagnosis of pyogenic meningitis from CSF sample. Out of 150 CSF samples studied, 40 were diagnosed as pyogenic meningitis. H. influenzae was the commonest organism (22.5%), followed by Streptococcus pneumoniae 15%, Staphylococcus aureus--10%, Acinetobacter species and coagulase negative Stapylococci 7.5% each, E-coli 5%, and a case each of Klebsiella species, Group B streptococci, Proteus, Pseudomonas and Enterococci. The sensitivity of Gram stain and Latex agglutination test was 90% and that of CRP test was 62.5%. As most of the cases included in our study were treated earlier, the culture positivity was only 62.5%. Hence, Gram stain and/or latex agglutination tests, if done properly are most rapid and reliable tests for the diagnosis of pyogenic meningitis.

Prevalence of methicillin resistant Staphylococcus aureus in Karnataka.

This study was undertaken to find out the prevalence of methicillin resistant Staphylococcus aureus (MRSA) infection in our hospital and to compare their antibiotic susceptibility pattern with methicillin sensitive Staphylococcus aureus (MSSA). 100 strains of Staphylococcus aureus isolated from various clinical samples were screened for MRSA by disc diffusion method using 1 gm oxacillin disc. Antibiotic sensitivity testing was done by Kirby-Bauer's disc diffusion method. Out of these, 43% were identified as MRSA and the remaining 57% were MSSA. There was a marked difference in antibiotic sensitivity pattern of these M RSA versus the MSSA isolates. None of the MRSA isolate was found to be sensitive to amoxycillin while 36.8% of MSSA were sensitive to this antibiotic. 9.3%, 18.6%, 34.9% and 95.3% of MRSA were sensitive to cotrimoxazole, cloxacillin, ciprofloxacin and chloramphenicol, while 75.4%, 92.9%, 91.2% and 94.7% of MSSA were sensitive to these antibiotics respectively. Sensitivity to macrolide group of antibiotics like erythromycin and roxithromycin were seen in 7% and 14% of MRSA in comparison to 85.9% and 91.2% of MSSA respectively. Amongst the aminoglycosides like gentamicin and amikacin, the sensitivity of MRSA was found to be 18.6% and 46.5% and that of MSSA was 98.2% and 94.7% respectively. Sensitivity to cephalosporins like cephalexin and cefotaxime was seen in 23% and 25.5% of MRSA, whereas 100% of MSSA were sensitive to these antibiotics. All Staphylococcus aureus isolates were found to be uniformly sensitive to vancomycin. Majority of the isolates belonged to phage group III and the common phage types were 54, 54/75 and 54/75/85.

Rapid diagnosis of cholera by coagglutination test.

In this study the coagglutination test for the rapid diagnosis of cholera is evaluated in comparison with the conventional culture method. A total of 553 stool specimens were processed from cases of acute gastro-enteritis. The sensitivity and specificity of coagglutination test was 92.77% and 95.65% respectively. The coagglutination test is found to be simple, reliable and rapid method for the diagnosis of cholera.

Serotypes and phage types of Vibrio cholerae in Mysore.

A total of 565 samples of acute diarrhoeal stools from children received over a period of twelve months from November 1996 to October 1997, yielded 289 (51.15%) isolates of V. cholerae. Out of these, 277 (95.85%) were V. cholerae 01 serotype Ogawa, 7 (2.42%) were V. cholerae 0139 and 5 (1.73%) were V. cholerae non-O1 non-0139. Phage typing of the isolates was carried out by NICED Calcutta. Out of 78 isolates, 69 (88.46%) belong to phage type T27. Of the remaining, 3 (3.85%), 3(3.85%), 2(2.56%) and 1(1.28%) belong to the phage types T26, T13, T8 and T4 respectively.