Comparative analysis of cerebrospinal fluid adenosine deaminase in tuberculous and non-tuberculous meningitis.

OBJECTIVE: To calculate cut-off point for the adenosine deaminase (ADA) activity in the CSF of patients with tuberculous meningitis (TBM). PATIENTS AND METHODS: The ADA assay was based on the automatic indirect method in which ADA catalyzes adenosine to inosine. ADA activity in the CSF was calculated based on ammonia liberated from adenosine and quantified spectrophotometrically. Arithmetic mean values and standard deviation of each variable were measured. Mann-Whitney U and Fisher exact tests were applied to compare continuous and dichotomous variables between tuberculous and non-tuberculous groups. A receiver operating characteristic curve was plotted to identify various cut-off points to determine the best level for ADA activity. RESULTS: Totally 42 patients were enrolled into the study. The median of ADA activity in the TBM group was 22 and in the non-TBM group was 8.0. The mean CSF-ADA activity was found to be significantly higher in TBM group (23.05+/-13.1IU/L) than in the CSF from non-TBM patients (9.39+/-5.18IU/L). The highest accuracy is at the cut-off value of 10.5IU/L. The sensitivity and specificity of the test at this cut-off to differentiate TBM from non-tuberculous meningitis is 81% and 86% respectively. CONCLUSION: Considering that a high positive value of ADA activity cannot confirm TBM, however, in suspected patients it may lead the physician to treat patient earlier before the confirmatory diagnostic reports will be received. The suggested cut-off value in this pilot study is 10.5IU/L with high sensitivity and specificity.

Serum adenosine deaminase activity in gestational diabetes mellitus and normal pregnancy.

PURPOSE: To our knowledge, there is no report regarding adenosine deaminase activity (ADA) in gestational diabetes mellitus (GDM). The aim of the present study was to investigate the level of serum ADA activity in normal pregnancy, GDM and normal non-pregnant women. METHODS: The serum catalytic concentration of ADA was measured in samples of 20 GDM, 40 normal pregnant and 20 non-pregnant healthy women. RESULTS: Adenosine deaminase activity was significantly higher in GDM (24.30 +/- 8.04 IU/L) and pregnant women (23.88 +/- 8.66 IU/L) than those of normal non-pregnant individuals (11.85 +/- 3.23 IU/L) (P < 0.0001), but the ADA level was not significantly different from GDM and normal pregnant women (P = 0.97). CONCLUSIONS: Adenosine deaminase activity was significantly higher in GDM and pregnant individuals than normal group in this study. Previous reports in this field are contentious; therefore, ADA activity could be regulated in different population by immunologic and genetic factors.

Serum trypsin inhibitory capacity in normal pregnancy and gestational diabetes mellitus.

BACKGROUND: Alpha-1-antitrpsin (AAT) is the main antiprotease of plasma. Concentration of serum alpha-1-antitrypsin (AAT) may not be delegate of the functional capacity of this antiprotease. To our knowledge there is not any report regarding the functional level of AAT in gestational diabetes mellitus (GDM). The aim of the present study was to determine serum trypsin inhibitory capacity (sTIC) in gestational diabetes mellitus. METHODS: This case-control study was performed in 41 GDM and 40 healthy pregnant women. sTIC was measured by enzymatic assay. RESULTS: The serum trypsin inhibitory capacity was significantly lower (p<0.001) in GDM (5.84+/-2.27 micromol/min/ml) than healthy pregnant women (7.24+/-1.91 micromol/min/ml). CONCLUSION: In gestational diabetes mellitus reduction of serum trypsin inhibitory capacity may be due to non-enzymatic glycosylation of alpha-1-antitrypsin or oxidation of methionin in the active site of alpha-1-antitrypsin which remains to be cleared.