Serum adenosine deaminase levels in diagnosis of acute appendicitis

Adenosine deaminase inhibition

Adenosine deaminase is a critical enzyme in purine metabolism that regulates intra and extracellular adenosine concentrations by converting it to inosine. Adenosine is an important purine that regulates numerous physiological functions by interacting with its receptors. Adenosine and consequently adenosine deaminase can have pro or anti-inflammatory effects on tissues depending on how much time has passed from the start of the injury. In addition, an increase in adenosine deaminase activity has been reported for various diseases and the significant effect of deaminase inhibition on the clinical course of different diseases has been reported. However, the use of inhibitors is limited to only a few medical indications. Data on the increase of adenosine deaminase activity in different diseases and the impact of its inhibition in various cases have been collected and are discussed in this review. Overall, the evidence shows that many studies have been done to introduce inhibitors, however, in vivo studies have been much less than in vitro, and often have not been expanded for clinical use.

Correlation of serum C-reactive protein, white blood count and neutrophil percentage with histopathology findings in acute appendicitis

BACKGROUND

Acute appendicitis is one of the most common surgical emergencies. Accurate diagnosis of acute appendicitis is based on careful history, physical examination, laboratory and imaging investigation. The aim of the study is to analyze the role of C-reactive protein (CRP), white blood count (WBC) and Neutrophil percentage (NP) in improving the accuracy of diagnosis of acute appendicitis and to compare it with the intraoperative assessment and histopathology findings.

MATERIALS AND METHODS

This investigation was a prospective double blinded clinical study. The study was done on 173 patients surgically treated for acute appendicitis. The WBC, NP, and measurement of CRP were randomly collected pre-operatively from all involved patients. Macroscopic assessment was made from the operation. Appendectomy and a histopathology examination were performed on all patients. Gross description was compared with histopathology results and then correlated with CRP, WBC, and NP.

RESULTS

The observational accuracy was 87,3%, as compared to histopathological accuracy which was 85.5% with a total of 173 patients that were operated on. The histopathology showed 25 (14.5%) patients had normal appendices, and 148 (85.5%) patients had acutely inflamed, gangrenous, or perforated appendicitis. 52% were male and 48% were female, with the age ranging from 5 to 59 with a median of 19.7. The gangrenous type was the most frequent (52.6%). The WBC was altered in 77.5% of the cases, NP in 72.3%, and C-reactive protein in 76.9% cases. In those with positive appendicitis, the CRP and WBC values were elevated in 126 patients (72.8%), whereas NP was higher than 75% in 117 patients (67.6%). Out of 106 patients with triple positive tests, 101 (95.2%) had appendicitis. The sensitivity, specificity, and positive predictive values of the 3 tests in combination were 95.3%, 72.2%, and 95.3%, respectively.

CONCLUSION

The raised value of the CRP was directly related to the severity of inflammation (p-value <0.05). CRP monitoring enhances the diagnostic accuracy of acute appendicitis. The diagnostic accuracy of CRP is not significantly greater than WBC and NP. A combination of these three tests significantly increases the accuracy. We found that elevated serum CRP levels support the surgeon's clinical diagnosis.

Serum adenosine deaminase activity as a predictor of disease severity in ulcerative colitis

BACKGROUND AND AIM

Ulcerative colitis (UC) is a chronic inflammatory disease characterized by recurrent inflammation and ulcerations of colonic mucosa and an inappropriate and delayed healing. Adenosine deaminase (ADA) is a cytoplasmic enzyme involved in the catabolism of purine bases, capable of catalyzing the deamination of adenosine, forming inosine in the result process. Although ADA has been shown to increase in several inflammatory conditions, there are no literature data indicating an alteration in UC.

METHODS

This study evaluated the activity of total ADA in serum of 43 patients with UC and 18 healthy controls. Patients' age, disease duration, drug intake, and other medical history were all noted for each subject. Complete blood count, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were determined for both patients and controls. Correlation analysis was also performed between ADA and other inflammation markers of UC.

RESULTS

Serum mean ADA levels were 11.12 ± 2.03 and 7.99 ± 2.04 U/l for patients with UC in active state and in remission and 8.55 ± 2.26 U/l in the healthy control group. Mean serum ADA levels were significantly elevated in active UC patients compared with patients with UC in remission and control groups. Overall accuracy of ADA in determination of active UC was 83.7 with sensitivity 83.3%, specificity 84.2%.

CONCLUSIONS

Serum ADA levels were found to be elevated in UC patients in active state suggesting a partial role of activated T-cell response in the disease pathophysiology. Further randomized controlled studies are warranted to demonstrate the role of ADA in UC patients, with a special interest in specifically targeted therapies against ADA for achieving disease remission.

Elevated adenosine deaminase levels in celiac disease

Celiac disease (CD) is a genetically based chronic inflammatory disorder of the small bowel induced by the dietary gluten and possibly other environmental cofactors. The objective of this study was to investigate the relation of adenosine deaminase (ADA), a cytoplasmic enzyme involved in the catabolism of purine bases, as an index of altered immune response, with adult CD patients. ADA has been shown to increase in several inflammatory conditions, but there is no literature data indicating an alteration in CD. Serum levels of ADA were investigated in newly diagnosed 20 CD patients. ADA levels were compared in patients with CD and in healthy controls. Correlation analysis was also performed between ADA and other serum markers of CD (anti-gliadin and anti-endomysial antibodies) Mean serum ADA levels were significantly elevated in CD patients compared with control group. ROC curve analysis suggested that the optimum ADA level cut-off point for CD was 12.27 U/l. At a cut-off value of 12.27 U/l, the sensitivity was 80% and specificity was 100%. There was no statistically significant correlation between ADA and anti-gliadin and anti-endomisium antibodies. Serum ADA levels elevated significantly in CD patients, suggesting a partial role in activated T-cell response in the disease pathophysiology. ADA can be used as a supportive diagnostic marker in patients with CD.

An in vitro comparison of a new vinyl chalcogenide and sodium selenate on adenosine deaminase activity of human leukocytes

Selenium (Se) is a dietary essential trace element with important biological roles. Sodium selenate (Na(2)SeO(4)) is an inorganic Se compound used in human and animal nutrition that acts as precursor for selenoprotein synthesis. The organoselenium 3-methyl-1-phenyl-2-(phenylseleno)oct-2-en-1-one (C(21)H(2)HOSe) is an α,β-unsaturated ketone functionalized vinyl chalcogenide that has been found as a potential tool in organic synthesis. Adenosine deaminase (ADA) is an important enzyme in the degradation of adenine nucleotides. In this study, we investigated the in vitro effects of both Se compounds on ADA activity and cell viability in leukocyte suspension (LS) of healthy donors (n=12). We first observed an inhibition of ADA activity using 0.1 μM of 3-methyl-1-phenyl-2-(phenylseleno)oct-2-en-1-one, and an increase in cellular viability when 30 μM were used. However, we did not observe alterations in the presence of sodium selenate. Moreover, both Se compounds did not alter lactate dehydrogenase activity and thiobarbituric acid reactive substance levels. These results suggest that the inhibition of ADA activity caused by α,β-unsaturated ketone may affect the adenosine levels in LS and modulate cell viability, attenuating conditions that involve the activation of the immune system.