Adenosine Deaminase Activity Levels Research Articles

Regulation of Hypoxic-Adenosinergic Signaling by Estrogen: Implications for Microvascular Injury.

Loss of estrogen, as occurs with normal aging, leads to increased inflammation, pathologic angiogenesis, impaired mitochondrial function, and microvascular disease. While the influence of estrogens on purinergic pathways is largely unknown, extracellular adenosine, generated at high levels by CD39 and CD73, is known to be anti-inflammatory in the vasculature. To further define the cellular mechanisms necessary for vascular protection, we investigated how estrogen modulates hypoxic-adenosinergic vascular signaling responses and angiogenesis. Expression of estrogen receptors, purinergic mediators inclusive of adenosine, adenosine deaminase (ADA), and ATP were measured in human endothelial cells. Standard tube formation and wound healing assays were performed to assess angiogenesis in vitro. The impacts on purinergic responses in vivo were modeled using cardiac tissue from ovariectomized mice. CD39 and estrogen receptor alpha (ERα) levels were markedly increased in presence of estradiol (E2). Suppression of ERα resulted in decreased CD39 expression. Expression of ENT1 was decreased in an ER-dependent manner. Extracellular ATP and ADA activity levels decreased following E2 exposure while levels of adenosine increased. Phosphorylation of ERK1/2 increased following E2 treatment and was attenuated by blocking adenosine receptor (AR) and ER activity. Estradiol boosted angiogenesis, while inhibition of estrogen decreased tube formation in vitro. Expression of CD39 and phospho-ERK1/2 decreased in cardiac tissues from ovariectomized mice, whereas ENT1 expression increased with expected decreases in blood adenosine levels. Estradiol-induced upregulation of CD39 substantially increases adenosine availability, while augmenting vascular protective signaling responses. Control of CD39 by ERα follows on transcriptional regulation. These data suggest novel therapeutic avenues to explore in the amelioration of post-menopausal cardiovascular disease, by modulation of adenosinergic mechanisms.

Evaluation of Inflammatory markers in different stages of Chronic Renal Disease

Background: Chronic kidney disease (CKD) refers to a long-term loss of kidney function. The progression of CKD leads to the damage of other organs including cardiovascular disease which increased the risk of mortality. Early detection of kidney failure can slow down the end-stage renal disease. Aims and Objectives: To estimate the inflammatory marker Adenosine deaminase (ADA) activity in different stages of CKD. To correlate the level of ADA activity with Serum Creatinine with different stages of CKD on the basis of estimated glomerular filtration rate (eGFR). Materials and Methods: The participants having age more than 18 and <60 years having CKD have been enrolled as a study group. CKD was confirmed by calculating eGFR using Cockcroft-Gault equation, plasma creatinine estimation done in all the patients. This study was approved by the Ethical Committee of TMMC and RC. Results: It is observed that the incidence of CKD reaches its maximum strength during middle age. 28% of the young patients, i.e., 45 years of age or younger at the time of CKD, had increased level of ADA. Serum levels of ADA, Creatinine were higher among participants with lower level of eGFR. Inflammation was higher among those with lower eGFR. All biochemical parameter (ADA, CRP, ESR) shows the negative correlation with eGFR. eGFR shows a negative highly significant correlation withESR with a correlation coefficient of r=−4.702 (P<0.001). Conclusion: With the progression of Kidney disease (CKD stages 1–5) it comes to significantly increase of inflammatory markers as decrease in the eGFR with statistical significance. Inflammatory Biomarkers were inversely associated with the measure of kidney function. It is clear that a single indicator of renal function is not sufficient in evaluating the kidney disease stage.

Autologous Ex Vivo Lentiviral Gene Therapy for Adenosine Deaminase Deficiency

BackgroundSevere combined immunodeficiency due to adenosine deaminase (ADA) deficiency (ADA-SCID) is a rare and life-threatening primary immunodeficiency.MethodsWe treated 50 patients with ADA-SCID (30 in the United States and 20 in the United Kingdom) with an investigational gene therapy composed of autologous CD34+ hematopoietic stem and progenitor cells (HSPCs) transduced ex vivo with a self-inactivating lentiviral vector encoding human ADA. Data from the two U.S. studies (in which fresh and cryopreserved formulations were used) at 24 months of follow-up were analyzed alongside data from the U.K. study (in which a fresh formulation was used) at 36 months of follow-up.ResultsOverall survival was 100% in all studies up to 24 and 36 months. Event-free survival (in the absence of reinitiation of enzyme-replacement therapy or rescue allogeneic hematopoietic stem-cell transplantation) was 97% (U.S. studies) and 100% (U.K. study) at 12 months; 97% and 95%, respectively, at 24 months; and 95% (U.K. study) at 36 months. Engraftment of genetically modified HSPCs persisted in 29 of 30 patients in the U.S. studies and in 19 of 20 patients in the U.K. study. Patients had sustained metabolic detoxification and normalization of ADA activity levels. Immune reconstitution was robust, with 90% of the patients in the U.S. studies and 100% of those in the U.K. study discontinuing immunoglobulin-replacement therapy by 24 months and 36 months, respectively. No evidence of monoclonal expansion, leukoproliferative complications, or emergence of replication-competent lentivirus was noted, and no events of autoimmunity or graft-versus-host disease occurred. Most adverse events were of low grade.ConclusionsTreatment of ADA-SCID with ex vivo lentiviral HSPC gene therapy resulted in high overall and event-free survival with sustained ADA expression, metabolic correction, and functional immune reconstitution. (Funded by the National Institutes of Health and others; ClinicalTrials.gov numbers, NCT01852071, NCT02999984, and NCT01380990.)

Role of pleural fluid adenosine deaminase activity and lymphocytosis in the etiological diagnosis

Background: Pleural effusion is a common medical condition with many possible underlying etiologies. However, Tuberculosis is the most common cause of pleural effusion especially in countries like Nepal. Pleural uid lymphocytosis is seen in tuberculosis, malignancy and few auto-immune diseases. Adenosine Deaminase activity (ADA) level in tubercular pleural effusion is markedly increased compared to non-tubercular effusions. ADA estimation being a simple colorimetric method is suitable for the rapid diagnosis of tubercular effusion. This study aims to correlate the diagnostic ef cacy of ADA with the value of differential count (lymphocytosis) in establishing different etiology of pleural effusion. Materials and Methods: This is a cross sectional study of 50 cases with pleural effusion carried out in the department of Pathology, Green city hospital for the duration of Twenty one month’s dating from October 2014 to July 2016 AD. Results: Of all, tubercular pleural effusion accounted for 26%. ADA level was raised (≥40U/L) in 92% of Tubercular pleural effusion. The sensitivity and speci city of ADA alone to diagnose tubercular pleural effusion was 92% each and when lymphocytosis alone was considered sensitivity was 85% with speci city of 32% whereas the combined effect of both ADA with lymphocytosis was 100% (sensitivity) and 87% (speci city), 83% (positive predictive value) and 100% (negative predictive value) respectively with statistically signi cant p value (<0.05). Conclusion: We can conclude that the combination of pleural uid differential count (lymphocytosis >50%) and ADA level >40U/L provides with much more positive result than each component alone in differentiating tubercular effusion from other etiologies.

Evaluation of adenosine deaminase (ADA) and ADA1 and ADA2 isoenzyme activities in patients with pulmonary tuberculosis and tuberculous pleurisy

ObjectivesTuberculosis (TB) still remains an important medical problem due to high levels of morbidity and mortality worldwide. Tuberculous pleurisy is the most common form of extrapulmonary TB. Since tuberculous pleural effusion usually contains a low number of mycobacteria, the diagnostic sensitivity of both direct microscopy and pleural fluid cultures is relatively low.Adenosine deaminase (ADA) is an essential enzyme in the metabolism of purine nucleosides. For an adequate interpretation of ADA, it is important to highlight the fact that ADA is represented by two isoenzymes: ADA1 and ADA2. The ADA1 isoenzymes are found in all cells, with the highest activity in lymphocytes, whereas ADA2 isoenzymes appear to be found only in antigen-presenting cells.The aim of this study is to evaluate the ADA and ADA1 and ADA2 isoenzyme activity in patients with pulmonary TB and tuberculous pleurisy. MethodsThis study included 25 patients with pleural effusions (11 with pleural TB and 14 with nontuberculous etiologies), 35 patients with pulmonary tuberculosis (PTB) and 42 healthy subjects.Total ADA activity level in pleural fluid and blood plasma was measured by the “ADA-test kit” developed in the Republican Scientific and Practical Center for Epidemiology & Microbiology (Minsk, Belarus). The principle “ADA-test” is a colorimetric method in which adenosine is deaminated by ADA and the free ammonia is estimated. Estimated ADA2 activity was calculated from the ADA and 2′-deoxyadenosine deaminase activities using the affinity of ADA2 for the two substrates. ResultsThe mean plasma ADA level in patients with PTB was 19.2±3.3U/L that was significantly higher than the control group (10.4±0.6U/L). The difference between patients with pleural TB and the controls is also significant (18.2±2.5U/L versus 10.4±0.6U/L, p<0.05). A significantly higher activity of ADA1 and ADA2 in the blood plasma was observed in patients with PTB and pleural TB than those of the corresponding controls (p<0.05).With diagnostic thresholds of 12.5 and 16U/L respectively, the sensitivities of plasma ADA for PTB and pleural TB were 54% and 64%; their specificities 68% and 78%; AUC – 0.67 and 0.73, respectively.The ADA level in the pleural fluid was significantly higher in patients with TB pleural effusion. It was found that the mean ADA level in the pleural fluid was 74.6±7.9U/L in cases of pleural TB, as compared with 21.9±4.3U/L in non-tuberculosis effusion (p<0.05). These results indicate that pleural fluid ADA1 and ADA2 levels were higher in patients with pleural TB as compared with non-tuberculosis effusion.An analysis of the ROC curve for pleural fluid ADA activity showed that at the most accurate cut-off level of 53.4U/L, the sensitivity of the test for tuberculous pleurisy was 91% and the specificity was 93%. ConclusionThis study concluded that pleural fluid ADA analysis could be an easy, cheap and highly sensitive and specific test for the diagnosis of pleural TB.

Diagnostic feature of tuberculous peritonitis in patients with cirrhosis: A matched case-control study

The aim of the present study was to compare the clinical characteristics of tuberculous peritonitis (TBP) and spontaneous bacterial peritonitis (SBP) in patients with cirrhosis. A retrospective, matched case-control study was conducted consisting of 12 patients with cirrhosis diagnosed with TBP between 2008 and 2011. Control subjects were patients with SBP. Clinical features and laboratory data were analyzed. Compared with SBP, TBP in patients with cirrhosis was frequently associated with extraperitoneal tuberculosis (25 vs. 0%), a more insidious onset (39.67±30.00 vs. 21.60±21.50 days; P<0.05), Child-Pugh classification B at onset (67 vs. 32%; P<0.05) and lymphopenia (0.67±0.22 vs. 1.19±0.41×109/l; P<0.01). Patients with TBP tended to have lymphocytic predominance in the peritoneal fluid (92%), while patients with SBP tended to have neutrophil predominance (68%). Compared with the SBP group, the TBP group had significantly higher ascitic protein, adenosine deaminase (ADA) and lactate dehydrogenase (LDH) levels. Ascitic protein levels were >25 g/l in 9 patients (75%) in the TBP group and in 2 patients (8%) in the SBP group; ascitic ADA activity levels were >27 U/l in 8 patients (67%) in the TBP group, but were not >27 U/l in any of the patients in the SBP group; ascitic LDH levels were >90 U/l in 10 patients (83%) in the TBP group and 5 patients (20%) in the SBP group. Therefore, the results of the present study indicate that TBP should be considered in cirrhotic patients with relevant clinical manifestations and characteristics of laboratory observations.

A Hospital Based Study on Estimation of Adenosine Deaminase Activity (ADA) in Cerebrospinal Fluid (CSF) in Various Types of Meningitis.

Tuberculosis kills 3.70 lakh patients in India every year,out of which 7-12 % are meningeal involvement. Delay in its diagnosis and initiation of treatment results in poor prognosis and squeal in up to 25% of cases. The aim of the present study is to look for a simple, rapid, cost effective, and fairly specific test in differentiating tubercular aetiology from other causes of meningitis. In the present study we measured the adenosine deaminase activity (ADA) in Cerebrospinal Fluid (CSF) of Tubercular Meningitis (TBM) and non-TBM patients. Fifty six patients attending hospital with symptoms and signs of meningitis were selected and divided into three groups: tubercular, pyogenic, and aseptic meningitis, depending upon the accepted criteria. CSF was drawn and ADA estimated. Out of 32 tubercular patients, 28 had CSF-ADA at or above the cut-off value while four had below. Out of 24 non-tuberculous patients (pyogenic and aseptic meningitis), two aseptic meningitis (AM) patient had ADA levels at or above the cut-off value while 22 had below this value. RESULTS of our study indicate that ADA level estimation in CSF is not only of considerable value in the diagnosis of TBM, CSF, and ADA level 10 U/L as a cut-off value with sensitivity 87.5% and specificity 83.33% and positive predictive value of the test was 87.5%.and 83.3% negative predictive value. It can be concluded that ADA estimation in CSF is not only simple, inexpensive and rapid but also fairly specific method for making a diagnosis of tuberculous aetiology in TBM, especially when there is a dilemma of differentiating the tuberculous aetiology from non-tuberculous ones. For this reason ADA estimation in TBM may find a place as a routine investigation.

Study of Adenosine Deaminase Levels Along With Alanine and Aspartate Aminotransferase, Total Proteins and A/G Ratio in Cirrhosis

Liver is the most bio-chemically complex organ. It plays a vital role in the metabolism and in the detoxification and elimination of toxic substances. Alcohol is the most common cause of hepatic injury terminating in cirrhosis. Acetaldehyde metabolite formed during the metabolism of ethanol is very reactive compound and is the mediator of tissue and organ damage. Many individuals with liver disease maintain normal function despite extensive liver damage. In such cases measurement of liver enzymes which are released into circulation as a result of liver cell injury, through non-specific may be helpful to assess the severity of liver damage. Main aim of the study is to evaluate the serum adenosine deaminase activity (ADA) along with other known markers of liver function such as alanine aminotransferase (ALT), aspartate aminotransferase (AST),, Total proteins and A/G ratio in patients with alcoholic cirrhosis, infective hepatitis and to assess the utility of these parameters as diagnostic and prognostic indicators of liver function. This study was done at Gandhi Hospital secunderabad; The patients included in the study were selected from out-patient and wards of Gastroenterology department of Gandhi hospital. Oral informed consent was taken from the persons who were included in the study. 12 individuals aged between 25-60 yrs were taken as controls. Most of them were males. 12 patients clinically diagnosed as alcoholic cirrhosis, confirmed by history, abdominal ultrasound scan and altered liver functions and 11 patients with viral hepatitis(serologically positive for HbsAg) were selected for study. In our study raised serum ADA levels are seen in cirrhosis patients when compared to normal individuals. Serum transaminases showed moderate raise when compared to normal individuals. Serum AST levels were greater than ALT. The serum AST: ALT ratio is >1. The total serum proteins showed marked reduction when compared to normal individuals. Serum albumin is reduced to greater extent. Serum globulins were increased when compared to normal individuals, resulting in reversal of normal A/G ratio. The reverse of A/G ratio indicates the severity of disease.

FRI0472 The level of adenosine deaminase activity in synovial fluid in patients with rheumatoid arthritis and osteoarthritis

BackgroundDuring last years, the great attention is paid to the identification of biomarkers which can help in differentiating the type of arthritis. The recent studies have shown Adenosine deaminase (ADA)...

The diagnostic efficiency of QuantiFERONTB®-Gold test in the diagnosis of tuberculous pleurisy

BackgroundDiagnosis of tuberculous pleurisy is difficult and better diagnostic tools are needed. Interferon gamma release assays (IGRAs) are in vitro immunologic diagnostic tests used to identify Mycobacterium TB infections. They cannot differentiate between latent and active infections. As IGRA tests have recently been approved for the differential diagnosis of active TB, the diagnostic accuracy of the latest generation of IGRA were assessed to detect tuberculous pleurisy in this study. MethodsThe QuantiFERONTB®-Gold (QFT-G) test was used in pleural fluid from 100 immunocompetent patients (23 patients for the tuberculous group and 77 patients for the non-tuberculous group). Clinical data were recorded. Adenosine deaminase activity (ADA) analysis and TB culture were performed on pleural fluid. ResultsThe QFT-G in pleural fluid was positive in 10 (43.5%) patients and indeterminate in 13(56.5%) patients in the tuberculous pleurisy group. There was not a single patient with a negative test result in the tuberculous pleurisy group. The ADA levels were detected as 46.2±12.6 in patients with tuberculous pleurisy and18.6±39.8 in patients with non-tuberculous pleurisy. The sensitivity, specificity, positive predictive value and negative predictive value of QFT-G in pleural fluid for tuberculous pleurisy were 43.5%, 54.5%, 30.3% and 100%; and of ADA in pleural fluid (>40IU/ml) for tuberculous pleurisy the results were 82.6%, 96.1%, 90.5% and 92.5% respectively. ConclusionWhile the value of the QFT-G test in exclusion of tuberculous pleurisy was found to be higher in this study, its other diagnostic efficiency values were detected to be low. It is recommended that a new cut-off value be established while diagnosing active TB in prospective clinical studies and that it is also essential to do the same for the studies in various regions with high and low prevalence of TB.

Evaluation of Cerebrospinal fluid adenosine deaminase activity as a complimentary tool in the early diagnosis of tuberculous meningitis in children

The diagnosis of tuberculous meningitis cannot be made or excluded on the basis of clinical findings. Definite laboratory diagnosis is cumbersome and time consuming. Delay in diagnosis and institution of proper treatment is directly related to poor outcome and sequalae. Adenosine deaminase activity (ADA) was estimated in cerebrospinal fluid (CSF) in addition to routine CSF analysis of 32 patients of tuberculous meningitis (TBM) and 7 patients of partially treated pyomeningitis (PTM), 10 patients aseptic meningitis (AM) and 13 patients pyogenic meningitis (PM). Mean ADA levels in CSF of TBM patients were higher (15.42 U/L) as compared to 7.21 U/L, 6.41 U/L and 7.50 U/L in PTM, AM and PM respectively. This difference of ADA values in CSF between TBM and other types of meningitis was statistically significant (p&lt;0.01). ADA values were also compared with other biochemical and cytological parameters of CSF &amp; a positive correlation was found with CSF protein level. Sensitivity and specificity of ADA levels in CSF of children to diagnose tuberculous meningitis was 75% and 90% respectively at 10 U/L cut off of ADA levels in CSF. Journal of College of Medical Sciences-Nepal,2012,Vol-8,No-2, 17-23 DOI: http://dx.doi.org/10.3126/jcmsn.v8i2.6833

ADA-SCID with ‘WAZA-ARI’ mutations that synergistically abolished ADA protein stability

ADA-SCID with ‘WAZA-ARI’ mutations that synergistically abolished ADA protein stability

La péricardite tuberculeuse : un diagnostic qui reste d’actualité

Vaccination against tuberculosis is not an obligation anymore in France, except for children at risk, but this disease remains not so rare, including its extrapulmonary forms. The authors report the case of a 27-year-old Madagascan HIV seronegative patient, who developed a pericardial effusion when coming back from a long stay in Madagascar. An anti-inflammatory treatment and then a probabilistic antibiotic treatment were ineffective, and at the same time echocardiographic signs of tamponade appeared. As a consequence, it was decided to perform a surgical pericardial drainage and a biopsy, and to introduce an antituberculosis chemotherapy, given the epidemiologic status. The course was then quickly favorable. The presence of granulomatous inflammation on the biopsy and an elevated pericardial adenosine deaminase activity level retrospectively supported the diagnosis of tuberculous pericarditis.

Adenosine deaminase activity, trypsin inhibitory capacity and total antioxidant capacity in psoriasis

Psoriasis is a chronic inflammatory skin disease characterized by pathological skin lesions because of various exogenous and endogenous factors and associated with a number of biochemical and immunological disturbances. The aim of the present study was to determine the level of adenosine deaminase activity, serum trypsin inhibitory capacity and total antioxidant capacity of plasma in psoriatic patients. The study was performed in controls (n = 46) and in psoriatic patients (n = 40). The patients were scored with PASI (psoriasis area and severity index). The serum ADA activity was determined using Aguisti and Galanti method and serum trypsin inhibitory capacity (sTIC) were measured by enzymatic assay. Besides, serum total antioxidant capacity was measured using ferric reducing ability of plasma. The serum ADA activity of the psoriatic patients was found to be significantly higher (P < 0.001) than that of the healthy control. We also found that the trypsin inhibitory capacity was significantly higher in patients than in control group (P < 0.001). Total antioxidant capacity of plasma was significantly lower in psoriatic patients than in healthy controls (P = 0.025). There were no significant correlations among ADA, TAC and TIC. Serum ADA activity and sTIC were increased in psoriatic patients. In parallel, serum total anti-oxidant activity was decreased in these patients.

Serum adenosine deaminase activity in gestational diabetes mellitus and normal pregnancy

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. The serum catalytic concentration of ADA was measured in samples of 20 GDM, 40 normal pregnant and 20 non-pregnant healthy women. 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). 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.

Comparison of Different Laboratory Routine Methods with Adenosine Deaminase Test for Diagnosis of Tuberculous Pericarditis in Two Iranian Teaching Hospitals, Tehran, Iran

In this study, laboratory routine tests were compared with adenosine deaminase (ADA) test for diagnosis of tuberculous pericarditis. Sampling was performed among 30 patients admitted to two Iranian teaching hospitals (Imam and Modarres). For each patient two specimens were obtained from the pericardial fluid and biopsy. Pericardial fluid was used for staining, culture and measuring of ADA activity. The biopsy specimens were homogenized and cultured on Lowenstein-jensen media too and examined by H & E stain for presence of caseous granulomas and tubercule bacilli. In this survey, the ADA activity level of less than 45 μL-1 in pericardial fluid were determined as negative, while more than 45 μL-1 were considered as positive reaction indicating of tuberculous pericarditis. In this study, from a total of 30 subjects, tuberculous pericarditis was diagnosed by routine laboratory tests in 13 patients who all had clinical symptoms of the disease. Tuberculous pericarditis was diagnosed by positive results of pericardial fluid cultures in 6 of 13 patients (46.2), by pericardial biopsy cultures in 6 patients (46.2), by pericardial fluid staining in 3 patients (23.1) and by tuberculin skin test in 10 patients (76.9). Finally we observed that all of 13 patients with tuberculous pericarditis had ADA levels of more than 45 μL-1 in their pericardial fluids. The results of the present study confirmed that high levels of ADA have a prognostic value and due to its high specificity and sensitivity and also being faster and easier than laboratory routine tests, so this test can utilized as effective diagnostic method for diagnosis of tuberculous pericarditis. © 2006 Asian Network for Scientific Information.

Adenosine Deaminase Activity in Tuberculous and Malignant Pleural Effusions

Measurement of pleural adenosine deaminase activity (ADA) is a useful diagnostic tool for tuberculous pleurisy, but false-positive findings from non-tuberculous effusions have been reported. In order to improve diagnostic value of ADA it is recommended to estimate activity of both ADA1 and ADA2 izoenzymes or 2'-deoxyadenosine/adenosine activity ratio. In order to evaluate ADA as a diagnostic parameter total ADA, with adenosine as a substrate, and 2'-deoxyadenosine/adenosine activity ratio were measured in tuberculous and malignant pleural effusions. Altogether, 26 pleural exudates (11 tuberculous and 15 malignant) were selected. ADA either with adenosine or 2'-deoxyadenosine was determined by colorimetric method of Giusti. Each pleural fluid sample was diluted prior to the assay (1:8) to avoid enzyme inhibition which was observed in nondiluted pleural effusions. The ADA level reached the diagnostic cut-off set for tuberculous effusions (40 U/L) in every 11 tuberculous exudates with the mean value of 85,3+/-47,1 U/L; in 9 of these the 2'-deoxyadenosine/adenosine ratio was less than 0,45. In the malignant group of patients, no one ADA level exceed 40 U/L, being estimated at 10,6+/-7,7 U/L (p<0,001). In 10 of these 15 exudates the 2'-deoxyadenosine/adenosine ratio was undetectable, in four it was less than 0,45 and only in one it was over 0,45. We concluded that ADA measured by the Giusti method proceeded by the dilution 1:8 of the pleural effusion samples very good differentiates tuberculous from malignant pleurisy, without the necessity to determine the 2'-deoxyadenosine/adenosine ratio. The investigation needs to be continued on the more numerous groups of patients.

Association of Adenosine Deaminase, Superoxide Dismutase, and Catalase Activities with Helicobacter pylori

Our purpose was to investigate associations between adenosine deaminase (ADA), superoxide dismutase (SOD), and catalase (CAT) activities and H. pylori.Ninety-nine patients were studied. Eight antral mucosal biopsies were taken for biochemical assessment of ADA, CAT, AND SOD activity and histological assessment. H. pylori density wAS evaluated according to the updated Sydney system. Patients were divided into three groups according to Sydney classification. ADA activity was found to be higher in patients having H. pylori in the present study. Also, ADA activity was higher in patients with a severe density of H. pylori. SOD level was found to be significantly higher with increased H. pylori density in our study (P < 0.05). In addition, SOD activity was higher in it H. Pylori-positive than H. pylori-negative patients. We did not find CAT activity in some antral tissue specimens. The significantly high levels of ADA activity in patients with H. pylori infection may reflect the regulator role of ADA in acid secretion. The higher ADA level with increased H. pylori density and H. pylori positivity indicate the probable malign lymphoid process of the stomach. But these findings must be confirmed with larger studies that include different gastric lesions.

The Utility of Pleural Fluid Cell IFN-γ Production Assay in the Diagnosis of Tuberculous Pleurisy

Background Diagnosis of tuberculous pleurisy is sometimes difficult using conventional diagnostic methods. We have investigated the utility of pleural fluid cell IFN-γ production assay in the diagnosis of tuberculous pleurisy. Methods We prospectively performed pleural fluid cell IFN-γ production assay in 39 patients with tuberculous pleural effusions (TPE) and in 26 patients with nontuberculous pleural effusions (NTPE) (13 malignant pleural effusions and 13 parapneumonic effusions). Pleural fluid cells were cultured in DMEM media and stimulated with purified protein derivatives (PPD), and phytohemagglutinin (PHA) for 24 hr. The amount of IFN-γ released in the culture supernatant was quantitated by IFN-γ ELISA assay. We have also measured adenosine deaminase (ADA) activities and IFN-γ concentrations in the pleural fluid. Results 1) The pleural fluid levels of ADA activity and IFN-γ concentrations were significantly higher in TPE than NTPE (p<0.01). 2) IFN-γ production in TPE cells stimulated by PPD (755,266±886,636 pg/ml) was significantly higher than NTPE cells (3,509±6,980 pg/ml) (p<0.01). By considering the fact that IFN-γ concentrations over 10,000 pg/ml is a criteria for the diagnosis of TBE, sensitivity and specificity of the test were 97.4 and 92.3%, respectively. 3) The ratios of IFN-γ production by the stimulation with PPD and PHA (PPD/PHA) were significantly higher in TPE cells (59±85) than NTPE cells (5±18)(p<0.01). Considering the criteria for the diagnosis of TBE as PPD/PHA ratio over 5, sensitivity and specificity of the test were 76.9 and 92.3%, respectively. Conclusion Pleural fluid cell IFN-γ production assay may be useful for the diagnosis of tuberculous pleurisy.

Adenosine deaminase levels in cerebrospinal fluid as a diagnostic test for tuberculous meningitis in children.

Adenosine deaminase activity (ADA) was estimated in cerebrospinal fluid (CSF) of 30 patients of tuberculous meningitis (TBM) and 10 patients each of partially treated pyomeningitis (PTM), aseptic meningitis (AM) and pyogenic meningitis (PM). Mean ADA levels in CSF of TBM patients were higher (18.22 U/L) as compared to 6.28 U/L, 3.43 U/L and 7.98 U/L in PTM, AM and PM respectively. This difference of ADA values in CSF between TBM and other types of meningitis was statistically significant (p<0.01) different. Sensitivity and specificity of ADA levels in CSF of children to diagnose tuberculous meningitis was 66.6% and 90% respectively at 10 U/L cut off of ADA levels in CSF. ADA levels in CSF could also differentiate PTM, AM and PM from TBM with a specificity of 90%, 100% and 80% respectively.