Comparative study of cerebrospinal fluid adenosine deaminase activity in patients with meningitis.

Cerebrospinal fluid (CSF) adenosine deaminase (ADA) activity in tubercular meningitis (TBM) patients (n=20), non-tubercular meningitis (NTBM) patients (n=10) and non-tubercular non-meningitis (NTBNM) cases (n=15) were measured by the method based on Berthlot's reaction. The mean CSF ADA activity in TBM (13.62 +/- 8.45 IU/L) was found to be significantly higher as compared to NTBM (6.51 +/- 2.41 IU/ L, p<0.001) and NTBNM (2.35 +/- 1.16 IU/L, p<0.0001) respectively. The sensitivity and specificity of CSF ADA activity was 85.0% and 88.0% respectively at cut-off value of 6.97 IU/L to diagnose tubercular meningitis. The specificity and sensitivity of CSF ADA for TBM was found to be 85.0% and 70.0% as compared to NTBM and 85.0% and 100.0% as compared to NTBNM. We propose that estimation of that ADA activity in CSF of TBM patients, using a cut off value 6.97 IU/L can diagnose differentially tubercular meningitis. Since, most developing countries have the dubious distinction of having higher prevalence and incidence of tubeculosis and lack of well equipped laboratory services for proper diagnosis of tubercular meningitis, measurement of CSF ADA activity can be a better and reliable approach for the rapid diagnosis and management of tubercular meningitis vis a vis other types of meningitis.

Antimicrobial susceptibility patterns of Salmonella enterica serotype typhi in eastern Nepal.

The aim of the present study was to evaluate antimicrobial susceptibility patterns with special reference to multidrug resistance, susceptibility to ciprofloxacin, and bacteriophage typing of Salmonella enterica serotype Typhi isolated from blood sent for culture in a tertiary-care teaching hospital in eastern Nepal during January 2000-December 2004. In total, 132 strains of S. enterica Typhi, isolated from 2,568 blood culture samples collected from cases of suspected enteric fever, were tested for susceptibility to commonly-used antimicrobials by the disc-diffusion method. There were 35 multidrug-resistant strains. None of the isolates were resistant to ciprofloxacin. Of 52 isolates tested for minimum inhibitory concentration (MIC) of ciprofloxacin, 36 (69.23%) showed reduced susceptibility (MIC >0.25 mg/L). Of 112 strains tested for nalidixic acid susceptibility, 86 (76%) were resistant. Strains with reduced susceptibility to ciprofloxacin and resistance to nalidixic acid could be correlated. The commonest phage type was El. Nalidixic acid susceptibility could be a useful screening test for the detection of decreased susceptibility of S. Typhi to ciprofloxacin, a drug which is commonly used even for minor ailments in this area.

Diagnostic utility of adenosine deaminase (ADA) activity in pleural fluid and serum of tuberculous and non-tuberculous respiratory disease patients.

Adenosine deaminase activity (ADA) was assayed in pleural fluid and serum of 42 subjects with pleural effusion. Twenty-nine of them had TB pleural effusion and the remaining 13 had pleural effusion due to non-TB respiratory diseases. Serum adenosine deaminase activity were also measured in 32 pulmonary tuberculosis patients without pleural effusion and equal numbers of healthy controls without systemic diseases for comparative analysis. The patients attending the medicine out-patient department (MOPD) of the B. P. Koirala Institute of Health Sciences, Dharan, Nepal were taken as study subjects. Serum and pleural fluid ADA activities were assayed spectrophotometrically by the method of Guisti and Gallanti. The mean serum ADA activity was significantly increased in patients with tubercular pleural effusion (34.53 +/- 10.27 IU/l) compared to pulmonary tuberculosis patients without pleural effusion (26.54 +/- 4.76 IU/l), (p = 0.004), those with non-TB respiratory disease (16.71 +/- 5.16 IU/l), (p = 0.0001) and healthy controls (15.53 +/- 4.4 IU/l) (p = 0.0001). The mean ADA in the pleural fluid of tubercular pleural effusion patients (90.29 +/- 54.80 IU/l) was significantly higher compared to those with non-TB respiratory disease (24.43 +/- 9.28 IU/l) (p = 0.0001). Using the lowest cutoff value for enzyme activity in the serum of patients with TB pleural effusion (25 IU/l), a test sensitivity of 72.41% and specificity of 81.53% were obtained. Using the lowest cutoff value for enzyme activity in pleural fluid of patients with TB pleural effusion (45 IU/l) the sensitivity and specificity for diagnosis were 76.10% and 100%, respectively. Therefore, the measurement of ADA in tubercular pleural effusion has a utility in the diagnosis of tuberculosis when other clinical and laboratory tests are negative.

Prevalence of Shigella species and their antimicrobial resistance patterns in Eastern Nepal.

The study was conducted to determine the prevalence of Shigella species and their antimicrobial resistance patterns in eastern Nepal. Stool samples submitted to the diagnostic laboratory of B.P. Koirala Institute of Health Sciences, Nepal, during August 2000-July 2004, were cultured for Shigella species and were confirmed by biochemical and serological tests. Of 53 Shigella species isolated, Shigella dysenteriae type 1 was the most predominant isolate (73.7%), followed by S. flexneri (23%) and S. boydii (4%). The majority (79%) of Shigella species were isolated from children aged less than five years. An overall high resistance was observed for trimethoprim-sulphamethoxazole, ampicillin, nalidixic acid, mecillinam, and ciprofloxacin. There was a statistically significant (p < 0.001) increasing trend in the prevalence of ciprofloxacin resistance in S. dysenteriae type 1. The results suggest reconsideration of the empiric use of these antimicrobial agents for shigellosis. A further study is required to evaluate additional antimicrobial agents.

Comparison of needle biopsy with pleural fluid analysis for the evaluation of pleural lesions.

A total of 60 pleural biopsies were received at Nidaan Clinic, Kathmandu during the period of two years from January 2000 to December 2002. The age of the patient ranged from 8 years to 82 years. Male: female ratio seen was 3:1. The most common lesion was found to be chronic nonspecific; pleuritis seen in 50.0% cases followed by tuberculous pleuritis in 36.7% cases, metastatic adenocarcinoma in 8.3% cases, metastatic small cell carcinoma in 3.3% cases and anaplastic large cell carcinoma in 1.7% cases. 63.3% cases of chronic nonspecific pleuritis showed transudative pleural fluid effusion. None of the cases of tuberculous pleuritis had transudative pleural effusion. 2 cases (40.0%) of metastatic adenocarcinoma had transudative pleural fluid effusion which suggests the need to perform pleural biopsy in all the cases of transudative pleural effusion whether encountered for malignancy or not.