Mean Adenosine Deaminase Level Research Articles

Serum Adenosine Deaminase Levels in Tubercular Lymphadenitis: Correlation and Cutoff

Objectives: Tubercular lymphadenitis accounts for the large majority of extrapulmonary tuberculosis (TB) worldwide. The available means for their diagnosis are often time-consuming, tedious, and costly. Adenosine deaminase (ADA) level estimation in body fluids has emerged as a popular method of diagnosing tuberculous infection. Very few studies have examined serum ADA levels in TB lymphadenitis and fewer such studies have used controls. The objective of the present study was to find any correlation between serum ADA and fine-needle aspiration cytology-confirmed tubercular lymphadenitis and, if a correlation existed, whether there existed any diagnostic cutoff for clinical utility. Material and Methods: This prospective study was done over 2 years. The patients were grouped into tubercular lymphadenitis (group 1, cases) and non-tubercular lymphadenitis (group 2, controls). Serum ADA level was estimated using the spectrophotometric method. Statistical methods were employed to examine the intergroup differences in serum ADA levels. The receiver operating characteristic curve (ROC curve) was used to assess the overall accuracy and corresponding diagnostic accuracy at different cutoff values of serum ADA. Results: Tubercular lymphadenitis (Group I) has a strong female predilection (M: F = 0.56:1, P = 0.017), a significantly late clinical presentation (P = 0.002), and a significantly higher incidence of cervical lymph node involvement (P = 0.019). A positive treatment history was significantly and more commonly found in patients of group 1 (P < 0.001) than patients of group 2. The mean serum ADA level was 43.14 IU/L. A significantly higher serum ADA level was detected in group 1 patients than in group 2 (56.81 ± 12.42 vs. 32.07 ± 6.84, P < 0.001). On ROC, the area under the curve was 97.2%, indicating a very good discriminating capability of serum ADA levels between groups 1 and 2. A cutoff value of 41.90 IU/L had the best sensitivity and specificity (93.15% and 92.1%, respectively) for detecting a tubercular etiology. Conclusion: Serum ADA level of 41.90 U/L can differentiate tubercular from non-tubercular lymphadenitis with a very high sensitivity and specificity. Therefore, serum ADA estimation can facilitate an early clinical diagnosis and institution of treatment.

Diagnostic and prognostic utility of serum adenosine deaminase in tuberculosis: Worth a revisit or are we flogging a dead horse?

Background Measurement of adenosine deaminase (ADA) activity in body fluids is one of the biochemical methods for the diagnosis of tuberculosis (TB). While the role of ADA levels in pleural fluid and cerebrospinal fluid for diagnosis of TB has been established, the role of serum ADA is yet to be established. Aims To study the role of serum ADA levels in diagnosis and prognosis of TB. Settings and Design This prospective observational study was carried out at a hospital in central India. All TB patients managed at the center in 2021 were included in the study. Materials and Methods Two hundred and thirty-three TB patients who met the inclusion criteria were recruited for the study. The subjects were divided into various study groups on the basis of TB subtypes. The study subjects were treated with first-line DOTS antitubercular therapy (ATT). The subjects underwent analysis of serum ADA levels at 0, 2, and 5 months of ATT initiation. Various factors affecting serum ADA levels were studied. Results There was no statistically significant difference in mean serum ADA levels among all study groups (I–IV) at month 0 (treatment initiation). The mean serum ADA levels of TB patients in all study groups (17.8 ± 5.1) were significantly higher than in the control group (10.1 ± 1.2). Mean serum ADA levels showed a sustained fall from month 0 to month 5 of treatment in all study groups. Low vitamin D levels (below 20 ng/mL), Mantoux negativity, and sputum smear status were not found to affect serum ADA levels. Conclusion Serum ADA levels can be used to evaluate response to ATT and for disease prognostication.

Role of thoracoscopy in diagnosis of tubercular pleural effusion in low ADA setting- A prospective, observational study

BackgroundTubercular Pleural effusion (TBPE) is one of most common extrapulmonary tuberculosis. It can be difficult to diagnose due to low sensitivity of pleural fluid smear, culture and CBNAAT. Diagnosis of TBPE is then dependent on the level of pleural fluid Adenosine Deaminase (ADA). Thoracoscopic pleural biopsy gives definite diagnosis specially in Low Pleural fluid ADA setting. Aims and objectiveThis study was planned to find out the prevalence of tubercular etiology in patients of exudative pleural effusion with low ADA (ADA <40 IU/L). Material and methodsA Prospective, observational study was carried out in a tertiary teaching institute in north India. Total 142 patients of pleural effusion with low ADA were enrolled. All patients underwent rigid thoracoscopy for confirmation of their diagnosis. ResultsOut of 142 patients, male were 78 (55%) and female were 64 (45%). Mean age of patients were 57.4 years. Tuberculosis was diagnosed as a cause of effusion in 22 (15.5%) out of 142 patients. Majority of TBPE patients had pleural thickening as thoracoscopic finding. Mean ADA level in TBPE was 27.36 ± 11.6 as compared to 18.55 ± 9.02 in non tubercular pleural effusion patients and this difference was significant statistically (P- 0.002). ConclusionThe diagnosis of patients having exudative, low ADA pleural effusion can be very easily confirmed by thoracoscopy guided pleural biopsy which has a very high diagnostic yield.

Diagnostic Value of Pleural Fluid Adenosine Deaminase In Patients With Pleural Tuberculosis

Background and Objectives Extra-pulmonary tuberculosis occurs in about 10-20% of patients with tuberculosis. It most commonly manifests as tuberculous lymphadenitis or pleural effusion. Pleural fluid Adenosine deaminase (ADA) activity considered as a useful biomarker for detecting pleural tuberculosis. The purpose of this study was to evaluate the diagnostic accuracy of pleural fluid adenosine deaminase level in patients with pleural tuberculosis. Methods In this study, 113 patients with exudative pleural effusion with unknown underlying diagnosis, were enrolled. Physical examination, chest CT, ADA level of pleural fluid, direct thoracoscopic examination, and biopsy of pleura were obtained for all individuals. ADA level and thoracoscipoc appearance of the lesions was then compaierd among the patients with regard to the pleural biopsy report as the diagnostic goldstandard. Results The diagnosis of tuberculous pleurisy was established in 40 individuals based on the pathology reports. The mean ADA level of the TB and the non-TB group was 39.90±22.93 IU/L and 30.74±38.27 IU/L, respectively (P-value=0.167). Sensitivity, specificity, positive predictive value, and negative predictive value of ADA test were 35%, 86.30%, 58.33%, and 70.79%, respectively. Conclusion Based insuffiecient sensitivity and specificity of ADA, in patients with unexplained exudative pleural effusion especially in those with a high suspicion of tuberculous pleurisy, despite the low level of ADA, direct thoracoscopic pleural evaluation with obtaining multiple biopsies of pleura is highly recommended.

Diagnostic utility of adenosine deaminase in bronchoalveolar lavage (BAL) in pulmonary tuberculosis from a tertiary care hospital in North India

Adenosine Deaminase (ADA) has been acclaimed as a biochemical marker in numerous studies in the diagnosis of tuberculosis of pleura, peritoneum, meninges etc because of its high sensitivity and specificity. As a diagnostic test, ADA offers several advantages; it is rapid, simple, low cost, non-invasive and can be performed easily in most clinical laboratories. The current retrospective study was carried out on a total of 91 specimens of bronchoalveolar lavage collected on bronchoscopy. The samples were collected and sediments were confirmed for presence of tubercular bacilli through Lowenstein Jensen(LJ) media (Gold standard), GeneXpert(CBNAAT).Simultaneously the ADA estimation was done from supernatant fluid obtained after centrifugation of sample.The Mean ADA level for Culture Positive samples in BAL was 5.899± 1.723 and from Culture Negative Samples the Mean ADA was1.217 ± 1.439. The ADA cut off levels of &amp;#62;4.0 IU/L in BAL when compared with LJ culture media (gold standard) showed a sensitivity of 90.0% and a specificity of 97.2%. Upon ROC analysis a high rate of accuracy was recorded in diagnosis of TB through ADA estimation with sensitivity and specificity reaching 100% and 97.2% at a ADA cut off 3.76 IU/L when compared with LJ culture media (gold standard). However, the sensitivity and specificity achieved was slightly lower when ADA results were compared with GeneXpert results.The determination of ADA levels may help in early diagnosis, improve the prognosis and reduce the spread of disease and thereby the test should be included in routine investigations in patients suspected of tuberculosis.

A prospective study for assessment of Serum Adenosine Deaminase, Erythrocyte Sedimentation Rate and C-Reactive Protein levels in patients with Psoriasis

The aim of this paper is to assess Serum Adenosine Deaminase (ADA), Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) levels in patients with Psoriasis. Sixty- four patients with psoriasis were divided into three groups (mild, moderate, and severe) based on PASI scores. PASI score &lt;10 defined psoriasis as mild, between 10 and 20 as moderate, and &gt;20 as severe. The hsCRP was assayed by an enzyme-linked immunosorbent assay BIOS kit. ADA was measured through kinetic method. ESR was calculated using Westergren method. Group I patients had 8 males (mild), 9 males (moderate) and 10 males (severe) and group II had 20 males. There were 12 females (mild), 14 females (moderate) and 11 females (severe) and group II had 30 females. A non- significant difference was observed (P&gt; 0.05). The mean hSCRP level in group I patients was 54.2 ng/ml and in group II was 19.6 ng/ml. The mean ADA level in group I patients was 22.5 U/L and in group II was 8.1 U/L. The mean ESR was 28.4 mm/h in group I and 13.2 mm/h in group II. A significant difference was observed (P&lt; 0.05). This study demonstrated higher hSCRP, ESR and ADA level among patients suffering from psoriasis compared to healthy control.

The value of adenosine deaminase level in assessing activation of inflammatory bowel disease

Aim: There is still a need for an ideal laboratory test that can determine the type of disease, the degree of its activity, predict its course, and monitor treatment response in patients with inflammatory bowel disease (IBD). This study aims to investigate the relationship between disease types and activity with Adenosine deaminase (ADA) levels in patients with IBD. Methods: A total of 92 patients with IBD [43 with Crohn’s disease (CD) and 49 with ulcerative colitis (UC)] and 31 healthy control (HC) volunteers were included in this case-control study. Patients’ age, gender, body mass index, location and severity of the disease, medication, endoscopic examination, hemogram, C-reactive Protein (CRP), and ADA results were evaluated. Results: The mean ADA level was 24.87 (9.6 - 74.9) IU/L in the IBD group and 20.8 (13.7 - 38.9) IU/L in the HC group. The difference between the IBD and HC groups was statistically significant (P<0.013), while that between UC and CD groups was not (P=0.76). Mean ADA level was significantly higher in active UC patients than in inactive ones (P<0.001). To distinguish active UC patients from those in remission, a cut-off level of 21.64 U/L was determined for ADA with 77.6% confidence interval, 89% sensitivity and 60% specificity. Mean ADA level was significantly higher in the CD group compared to the HC group. Conclusion: ADA level may be used as an alternative marker to distinguish active UC patients from those in remission, regardless of the disease location and the extent of the affected area.

Cerebrospinal fluid adenosine deaminase level as a diagnostic marker in adult tuberculous meningitis: a study conducted in a tertiary care hospital of Eastern India

Background: Tubercular meningitis is one of the highly prevalent form of meningitis in the world and is a significant cause of morbidity and mortality in developing countries like India. Lack of early and timely diagnosis and subsequent initiation of treatment makes the fatality rate even higher. Cerebrospinal fluid (CSF) analysis is most important aspect of lab diagnosis in tuberculous meningitis (TBM) worldwide. The objective of this study was to study the cerebrospinal fluid CSF adenosine deaminase (ADA) levels in TBM and non-TBM meningitis cases and to determine its diagnostic significance as a biochemical marker of TBM infection.Methods: The study population comprised three different patient groups. TBM (n=36), pyogenic meningitis (n=17) and aseptic meningitis group (n=12). Total 75 subjects were enrolled consecutively in the study and CSF specimens were collected from them. ADA and other cytological and biochemical estimation were carried out using standard protocol.Results: ADA level in TBM in compare to non-TBM was more and mean ADA level of TBM, AM and PM are 26.423±3.8, 2.602±0.5 and 6.29±0.3 respectively. There are highly significant differences between the TBM and non-TBM groups and also in compare with individual groups.Conclusions: CSF ADA levels are elevated in the TBM cases as compared to the non-TBM - meningitis cases. Results are statistically significant. It is a simple and inexpensive diagnostic adjunctive test in the rapid and early diagnosis of TBM.

EP28 Adenosine deaminase-genetic polymorphism and baseline serum level as a biomarker of treatment response to methotrexate in rheumatoid arthritis

Abstract Background Despite methotrexate (MTX) being the first line therapy for RA,30% of patients do not respond to MTX. Methotrexate acts by increasing adenosine levels which lead to anti-inflammatory effects. Adenosine deaminase (ADA) enzyme converts adenosine to inosine thus reduces levels of adenosine. Thus, ADA levels and single nucleotide polymorphism (SNP) in ADA gene may affect the treatment effect of MTX. Our objective was to study if genetic polymorphism in ADA gene and baseline serum ADA levels in patients with RA is associated with methotrexate response. Methods 207 DMARD naïve active RA (DAS28 ESR ≥3.2) patients satisfying EULAR/ACR 2010 criteria were enrolled. Genotyping was done in all patients (n = 207) by TaqMan 5' nuclease assay. In a subset of patients(n = 59) blood sample was collected at baseline and 2 months for ADA estimation by ELISA. Ethical approval and written informed consent was taken. Oral MTX was initiated at dose of 15mg/week, escalated 5mg every month till the patients had DAS28 &amp;lt; 2.6 or a maximum dose of 25 mg/week was reached. At 4 months based on EULAR response patients were classified as responders or non-responders. Using a Chi-squared test, SNPs were associated with response to methotrexate therapy. Baseline clinical parameters and serum ADA levels were correlated with EULAR response. Results Among 207 patients (177females) mean age was 41.49± 12.14 years and median disease duration 24 (40) months.172 patients (83.1%) were responders and 35 (16.9%) non-responders. 197 (95.16%) patients were seropositive (RF and/or ACCP+). With regard to SNP in ADA gene,47.8% were AA,42.5% AG and 9.7% were GG genotype. Mean DAS 28 CRP was 4.76 ± 1.05 and median DAS 28 ESR was 6.00 (1.38). Mean serum baseline ADA was 10.82 ±5.33 pg/dl. Except DAS28ESR (p = 0.02), other baseline parameters like age, disease duration, ESR, CRP, DAS 28 CRP were similar between responders and non-responders. SNPs in ADA gene were not associated with EULAR response (p = 0.475). Baseline ADA levels (10.52 ± 5.37 vs 12.28 ± 5.14; p = 0.34) 2 month ADA levels (p = 0.34) and change in ADA level from baseline at 2 months, i.e. delta ADA (p = 0.55) did not show any association with MTX response. Mean ADA level was similar between the 3 genotypes of ADA(p = 0.736) Comparison of parameters between methotrexate responders and non-responders Conclusion ADA gene polymorphism and serum ADA levels do not affect response to methotrexate. Disclosures H. Gangadharan Nair: Grants/research support; Indian Rheumatology Association Research grant. A. Singh: None. S. Majumder None. A. Aggarwal None.

Role of Adenosine Deaminase in Patients with Erythematotelangiectatic Rosacea and Demodex folliculorum Positivity.

Background:Adenosine deaminase (ADA) is an aminohydrolase involved in the catabolism of purine nucleotides and irreversibly deaminizes adenosine and deoxyadenosine to inosine and deoxyinosine. ADA enzyme deficiency results in the loss of functional properties of B and T lymphocytes. Demodex species have been reported to be transmitted between humans through close contact and to play a role in the pathogenesis of rosacea, acne vulgaris, perioral dermatitis, seborrhoeic dermatitis, micropapillary-pruritic dermatitis and blepharitis. The present study aimed to compare serum ADA levels in D. folliculorum positive patients with the healthy control individuals.Methods:Serum ADA levels were examined for 30 patients diagnosed with erythematotelangiectatic rosacea and 40 healthy individuals in Malatya Inonu University in 2017. Standardized skin surface biopsy (SSSB) method was used to diagnose D. folliculorum. A significant decrease was found in the ADA levels of Demodex-positive rosacea patients when compared to the control group.Results:ADA levels were decreased in the Demodex-positive group. The mean ADA level in patient group was significantly lower than the mean in the control group (P<0.001). There was no significant difference between the patient and control groups in terms of age and gender.Conclusion:During and after treatment of Demodex-positive rosacea patients, determination of ADA levels may give more detailed information on the immune mechanisms.

Diagnostic Value of Serum Adenosine Deaminase Level in Extrapulmonary Tuberculosis

Background: Although tuberculosis is a known disease, still on occasion, the tuberculosis patients remain undiagnosed and hence not treated appropriately. In some cases, the patient is not able to give a proper sputum sample. In some other cases, expert laboratory technician to examine the patient’s sputum smear is not available. Furthermore, and in most cases of extrapulmonary tuberculosis, invasive diagnostic procedures such as biopsy might be followed. The aim of this study was to investigate the diagnostic value of serum level of adenosine deaminase (ADA) in extra pulmonary tuberculosis. Methods: In this analytical study, pulmonary tuberculosis patients were compared with two other groups of patients including lung cancer patients and healthy controls, based on national tuberculosis protocol. In each group, 40 patients who almost matched for age and sex were included. Blood samples were taken from the participants to measure serum ADA levels. Data were analyzed using SPSS software version 15.0. Results: Based on the data analyzed in this study, the mean ADA level in the patients with extra pulmonary tuberculosis was 23.8 IU/L which was significantly higher than that in the other groups (P<0.001). Mean ADA levels in lung cancer patients and in healthy subjects were 15.8 IU/L and 10.7 IU/L, respectively. Conclusions: According to the results of this study, higher cut-off value for ADA would increase the specificity up to 100%. Moreover, serum ADA level can be a valuable additional index in diagnosis of extra pulmonary tuberculosis.

Pooled analysis of 163 published tuberculous peritonitis cases from Turkey

Background/aim: Tuberculous peritonitis may be difficult to diagnose due to its insidious and variable clinical manifestations as well as characteristics similar to malignancy. In this study, case reports from Turkey over the last 10 years were reviewed systematically using pooled analysis. Materials and methods: Thirty-four suitable articles were found and 163 tuberculous peritonitis cases were included in the study. Results: The mean age was 34.1 years (17–79 years), and 146 (98.6%) of the patients were female and 17 (10.4%) were male. The most common complaints of these patients were abdominal pain (77.4%) and abdominal distention (73.5%). Ascites in the abdomen (75%), fever (42%), abdominal tenderness (33%), and abdominal distention (30.7%) were the most common physical examination findings. The mean adenosine deaminase level was 120.3 IU/L. In the subsets of patients with relevant data, acid-fast bacilli were found in 23.3%, culture was positive in 22.2%, and Mycobacterium tuberculosis polymerase chain reaction was positive in 20%. In abdominal imaging, ascites was reported in 92%. Elevated serum CA-125 was reported in 96.7% of the patients. Of 105 patients with data available following the antituberculous therapy prognosis, four (3.8%) died and the other 101 (96.2%) showed good treatment response. Conclusion: Tuberculous peritonitis should be kept in mind during the differential diagnosis of patients admitted with the triad of ascites, fever, and abdominal distention.

Study of adenosine deaminase levels in Tb meningitis and its comparision with other types of meningitis

Tubercular meningitis is a type of septic meningitis and is a significant cause of morbidity and mortality in developing countries like India due to lack of early and timely diagnosis and so the case of fatality remains higher. Cerebrospinal fluid (CSF) evaluation is single most important aspect of lab diagnosis in meningitis. Aims: 1. To evaluate the diagnostic significance of CSF adenosine deaminase (ADA) activity in tuberculous meningitis. 2. To compare the values of CSF ADA in different types of meningitis and with that of controls. Materials and Methods: It was clinical cross-sectional study of 25 cases of tuberculosis, 25 cases of pyogenic meningitis, and 25 cases of aseptic meningitis. Twenty five controls with age and sex matched individuals without evidence of any neurological diseases served as control for CSF ADA. Results: In this study of 100 patients, 25 (100%) patients of the tubercular group had CSF ADA levels of more than 10 IU/dL with a mean of 13.68 IU/dL with 80% of the patients having ADA levels between 11 and 15 IU/dL. Mean ADA levels of aseptic meningitis was 8.00 IU/dL, pyogenic was 5.76 IU/dL, and control group had mean ADA of 2.12 IU/dL. Conclusion: All patients with tuberculous meningitis had elevated CSF ADA activity. CSF ADA activity in tuberculous meningitis was significantly higher when compared with pyogenic meningitis, aseptic meningitis, and controls.

Raised adenosine deaminase in the cerebrospinal fluid: A tool for the diagnosis of tuberculous meningitis in developing countries.

The rapid diagnosis followed by the early treatment of tuberculous meningitis (TBM) is important in preventing fatal outcomes. The mainstay of diagnosis lies in cerebrospinal fluid (CSF) analysis, radiological investigations, and clinical findings. The present study was conducted to determine the efficacy, sensitivity, and specificity of raised adenosine deaminase (ADA) level in CSF to differentiate TBM from non-TBM cases as a rapid, cost-effective, and noninvasive test. This was a retrospective study conducted over a 1-year period in a tertiary teaching institute of Malwa region, India. A total of 143 patients presented with symptoms and signs of meningitis were included and divided into TBM and non-TBM groups on the basis of the diagnostic criteria. CSF ADA estimation was drafted and analyzed by using ≥10 U/L as a cutoff value. A statistical comparison of the ADA levels between the study groups was made by using unpaired Student's t-test. Out of the 143 cases, 40 were TBM, and 103 were non-TBM. The mean ADA level in TBM and non-TBM cases was 17.18 ± 9.59 and 6.33 ± 2.48, respectively, and the difference was statistically significant. Using a cutoff level ≥10 U/L, CSF ADA had a sensitivity of 92.5% and a specificity of 89.32%. Positive and negative likelihood ratios of the test were 8.66 and 0.08, respectively, and positive and negative predictive values, were 77.08 and 96.84%, respectively. The present study reflects the importance of a CSF ADA level ≥10 U/L in the diagnosis of TBM. Thus, it can be used as an adjunctive diagnostic tool to differentiate TBM from other non-TBM cases, when there is a diagnostic dilemma.

Relationship between serum adenosine deaminase levels and liver histology in autoimmune hepatitis.

AIMTo evaluate the relationship between serum adenosine deaminase (ADA) levels and histological features in patients with autoimmune hepatitis (AIH).METHODSA total of 80 subjects (52 AIH cases and 28 healthy controls) were included in the study. Patients were diagnosed according to the simplified criteria suggested by the International Autoimmune Hepatitis Group. All of the cases had been diagnosed with AIH between 2010-2015 at Hacettepe University, Department of Gastroenterology. Serum blood samples were collected and stored at -80 °C until the biochemical estimation of ADA activity. The diagnosis of patients was confirmed by liver biopsy. Serum ADA > 20 U/L was considered to be high level.RESULTSMean serum ADA levels were significantly higher in AIH patients than those in healthy controls (25.4 ± 9.6 U/L vs 12.8 ± 2.2 U/L, P < 0.001). Serum ADA levels > 20 U/L were found in 63.5% AIH patients and in 0% healthy controls (P < 0.001). Mean serum ADA levels were significantly increased in each stage of histological activity: 15.2 ± 3.5 U/L for patients with mild interface hepatitis, 23.1 ± 10.0 U/L for patients with moderate interface hepatitis and 30.9 ± 7.0 U/L for patients with severe interface hepatitis (P < 0.001). Correlation analysis showed that there was a positive association between serum ADA levels and histological activity (r = 0.71, P < 0.001). Receiver operating characteristic analysis suggested that 24.5 U/L was the optimum cut-off point of ADA level for severe interface hepatitis (sensitivity 88%, specificity 85.2%, area under the curve: 0.88).CONCLUSIONBecause of the positive correlation with inflammatory activity, serum ADA level may be a potential biomarker for predicting or monitoring histological activity in patients with AIH.

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Does adenosine deaminase activity play a role in the early diagnosis of ectopic pregnancy?

Early diagnosis of ectopic pregnancy (EP) is important due to life-threatening consequences in the first trimester of pregnancy. In this study we aimed to investigate the role of adenosine deaminase (ADA) activity in the prediction of EP. Forty-one patients with unruptured ectopic pregnancy comprised the case group and forty-two first trimester pregnant women with shown foetal heart beating in ultrasound comprised the control group. The mean ADA level in EP (10.9 ± 3.0 IU/L) was higher than that in control group (9.2 ± 3.6 IU/L) (p = 0.018). Receiver operating characteristics or ROC curve identified ADA value of 10.95 IU/L as optimal threshold for the prediction of EP with 56% sensitivity and 67% specificity. High ADA levels are valuable in the early diagnosis of EP. However more comprehensive studies are required.

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.

Serum Adenosine Deaminase Level is High But Not Related with Disease Activity Parameters in Patients with Rheumatoid Arthritis

Serum adenosine deaminase (ADA) has been previously proposed to predict disease activity in patients with rheumatoid arthritis (RA). The aim of this study was to investigate the level of serum ADA, and the relationship between ADA and disease activity markers, in a group of patients with RA.A hundred and 10 patients with a diagnosis of RA were recruited from outpatient clinic of Rheumatology Unit. Demographic properties comprising age, gender, disease duration and drugs were recorded. Disease activity based on disease activity score (DAS)28-erythrocyte sedimentation rate (ESR) and DAS28- C reactive protein (CRP,) ESR, CRP levels, as well as pain by visual analog scale and rheumatoid factor (RF) were recorded. Serum ADA levels (IU/L) were determined in all RA patients and in 55 age and sex similar healthy control subjects.Ninety-six female and 14 male RA patients with a mean age of 54.32±11.51, and with a mean disease duration of 11.5±9.13 years were included to the study. The control group comprised of 48 female and 7 male healthy subjects. 35.5% of the patients were on methotrexate (MTX) and 64.5% of patients were on combined DMARDs or combined MTX and anti-TNF therapies. The mean serum ADA level was statistically higher in RA patients than in control subjects (27.01±10.6 IU/L vs 21.8 ±9.9 IU/L). The mean values of ESR (23.2±14.8 mm/h), CRP (1.71±1.11mg/dL), pain by VAS (37.2±27.1), DAS28-ESR (2.72±0.77), DAS28 CRP (1.37±0.5) were not correlated with ADA levels (p>0.05).Our results have shown that serum ADA levels are higher in RA patients than in controls but were not related with any of the disease activity markers. We conclude that ADA in the serum may not be a reliable biochemical marker to predict disease activity in patients with RA.

Clinical analysis of nontuberculous mycobacterial infection complicated by pleurisy

There are few reports describing pleurisy caused by nontuberculous pulmonary mycobacteriosis; in addition, there are few reports describing the frequency of cases. We retrospectively studied 116 consecutive cases of nontuberculous mycobacteriosis occurring between January 2009 and January 2014. Of these, 7 patients (6.0%) were diagnosed with pleuritis caused by nontuberculous pulmonary mycobacteriosis. One patient each had a history of ulcerative colitis, rheumatoid arthritis treated with steroids, and retinitis pigmentosa. Pleural effusion was examined in all 7 cases. In addition, nontuberculous mycobacteria were cultured from pleural effusion in 4 of the 7 cases; all were cases of Mycobacterium avium complex infection. The mean adenosine deaminase level in pleural effusion was 86 U/mL, and in 5 out of 7 cases, the adenosine deaminase level was greater than 50 U/mL. Pneumothorax occurred with pleuritis in 5 cases. Pleuritis was treated with NTM therapy in 5 cases, and pleural effusion decreased or cleared completely in all cases. To reveal pleurisy accompanied by nontuberculous mycobacteriosis, further consideration is needed.