Diagnostic value of serum adenosine deaminase levels in sputum smear negative pulmonary tuberculosis patients in Nepalese population

Role of serum adenosine deaminase in pulmonary tuberculosis

BACKGROUND

Definitive laboratory diagnosis and confirmation of tuberculosis remains a major challenge because of lack of specificity and sensitivity of diagnostic methods especially in sputum smear negative tuberculosis. Many studies have proved the role of ADA in diagnosis of tuberculosis in effusion fluids and a decrease in ADA activity after treatment. This study was aimed to investigate the role of serum ADA level as an early diagnostic and prognostic marker for pulmonary tuberculosis (PTB).

MATERIAL AND METHODS

This was a cohort study done on patients visiting the OPD Clinics of the department of Pulmonary Medicine at GMCH, Chandigarh. 50 sputum positive and 50 sputum negative tuberculosis patients and 100 controls were recruited. Serum ADA levels were measured at the start of treatment and again after two months of treatment. Its correlation with severity of disease was seen.

RESULTS

Mean serum ADA (IU/L) was found to be 35.293±30.941 in PTB patients and 11.819±8.023 in control groups and the difference was found to be highly significant (P<0.00). Mean ADA was 31.107±29.32 in sputum positive patients, 39.478±32.22 in sputum negative and 11.819±8.0235 in control groups. No statistically significant difference was observed amongst sputum positive and sputum negative patients. The levels decreased significantly after intensive phase of treatment. At the cut off values of 14.6IU/L, serum ADA had 78% sensitivity and 76% specificity (AUC=0.801, P value<0.00) to differentiate between PTB from healthy controls.

CONCLUSION

Serum ADA levels may be used as a biomarker for diagnosis of PTB and to evaluate the response to treatment at follow up.

Evaluation of Serum Adenosine Deaminase in Cystic Fibrosis Patients in an Iranian Referral Hospital

BACKGROUND

Adenosine, a signaling nucleoside, is controlled in part by the enzyme adenosine deaminase (ADA). There are rare reports on the role of adenosine levels and ADA in cystic fibrosis (CF) patients.

OBJECTIVES

The aim of this study was to assess serum ADA in CF patients in order to find whether the severity of lung disease in CF is related to significant changes of ADA or not.

PATIENTS AND METHODS

Venous blood serum ADA was measured in CF patients (3-15 years) and 49 healthy children (3-15 years) referred to Children's Medical Center. Classification of respiratory and gastrointestinal disease severity in CF patients as well as Body Mass Index (BMI) was performed. The results were compared with values obtained from healthy children matched for age and gender.

RESULTS

This study included 49 children of both genders (20 females and 29 males) with CF (mean age: 6.36 ± 2.22 years). Mean serum ADA in CF patients group and control group was 9.38 ± 2.72 and 16.04 ± 1.27, respectively (P value = 0.001). Mean serum ADA in CF patients with normal BMI was higher than in patients with low BMI (P value = 0.002).

CONCLUSIONS

In this study the lower serum level of ADA was seen in CF patients compared to control group. The clinical symptoms, especially respiratory symptoms, in CF patients might be associated with reduction of serum ADA and rising serum adenosine; therefore, further studies on the use of ADA enzyme therapy in CF patients are highly recommended.