Ascitic Fluid Adenosine Deaminase Insensitivity in Detecting Tuberculous Peritonitis in the United States

Abstract

Tuberculous peritonitis, although common in Third World countries, remains an uncommon cause of ascites in the United States. Ascitic fluid adenosine deaminase (ADA) activity has been proposed as a useful diagnostic test. The aim of this retrospective study was to determine the clinical utility of ascitic fluid ADA activity in diagnosing tuberculous peritonitis in a U.S. patient population. A total of 368 ascitic fluid specimens from a well-characterized ascitic fluid bank, including tuberculous peritonitis (n = 7), tuberculous peritonitis in the setting of cirrhosis (n = 10), and consecutive specimens of widely varied etiologies (n = 351) were analyzed for ADA activity by ultraviolet spectrophotometry at 265 nm. The overall sensitivity of the ADA determination in diagnosing tuberculous peritonitis was only 58.8%, and the specificity was 95.4%. The accuracy of ADA determination (93.8%) compared favorably with that of the common ascitic fluid tests of white blood cell (WBC) count (>500/mm3), total protein (>2.5 g/dL), and combined WBC count and total protein (45.8%, 74.4%, and 81.3%, respectively). However, ADA was only 30% sensitive in detecting tuberculous peritonitis in the setting of cirrhosis, and cirrhosis was present in 59% of the tuberculous peritonitis patients in our population. In addition, malignancy-related ascites (13%) and bacterial peritonitis specimens (5.8%) occasionally yielded false-positive results. In conclusion, our results indicate that the ascitic fluid ADA activity has good accuracy but poor sensitivity and imperfect specificity in a U.S. patient population in which the prevalence of tuberculosis is low and underlying cirrhosis is common.

Use of adenosine deaminase measurements and QuantiFERON in the rapid diagnosis of tuberculous peritonitis

“…Previous studies reported that the ADA assay has a sensitivity of 100 % and specificities in the range of 92-100 % for the diagnosis of TB peritonitis (Voigt et al, 1989;Fernandez-Rodriguez et al, 1991;Gupta et al, 1992;Brant et al, 1995). In contrast, Martinez-Vazquez et al (1986) found that the ADA assay was not specific for the diagnosis of TB peritonitis, and other studies showed that the sensitivity of the ADA assay was significantly lower for patients with underlying liver cirrhosis (Sathar et al, 1995;Hillebrand et al, 1996), a finding not observed in our current study. Although ADA levels were elevated in other infectious or inflammatory disorders, definite cut-off values were associated only with TB peritonitis.…”

A prospective audit of the use of diagnostic laparoscopy to establish the diagnosis of abdominal tuberculosis

“…13 Studies from a tuberculosis endemic area like South Africa have reported sensitivity and specificity exceeding 92% for this non-invasive test, 35 whereas the study from the United States showed that the ascitic fluid ADA activity has good accuracy but poor sensitivity and imperfect specificity, where the prevalence of tuberculosis is low and underlying cirrhosis is common. 36 Gamma (γ) interferon, secreted by antigen-triggered CD4+ lymphocytes, is a key lymphokine that activates macrophages, increasing their bactericidal activity against Mycobacterium tuberculosis. 34 Although the sensitivity and specificity of ascitic fluid ADA and γ-interferon activity are high in tuberculous peritonitis, their activities have been reported to be significantly lower in patients with low ascitic fluid protein concentration and in patients with AIDS, explained by a low lymphocyte activity due to the CD4+ lymphocyte depletion in HIV infection.…”

A Guide to the Management of Tuberculosis in Patients with Chronic Liver Disease

“…6 Laparoscopic biopsies and ultrasound or CT-guided fine needle aspiration cytology provide definitive diagnosis of tuberculous peritonitis. 7,8 …”