The role of histopathology in establishing the diagnosis of tuberculous pericardial effusions in the presence of HIV

AIMS: To establish the influence of human immunodeficiency virus (HIV) infection on the histopathological features of patients presenting with tuberculous pericarditis. METHODS AND RESULTS: A prospective study was carried out at Tygerberg Academic Hospital, South Africa; 36 patients with large pericardial effusions had open pericardial biopsies under general anaesthesia and were included in the study. Patients underwent pericardiocentesis, followed by daily intermittent catheter drainage; a comprehensive diagnostic work-up (including histopathology of the pericardial tissue) was also performed. Histological tuberculous pericarditis was diagnosed according to predetermined criteria. Tuberculous pericarditis was identified in 25 patients, five of whom were HIV+. The presence of granulomatous inflammation (with or without necrosis) and/or Ziehl-Neelsen positivity yielded the best test results (sensitivity 64%, specificity 100% and diagnostic efficiency 75%). CONCLUSIONS: Co-infection with HIV impacts on the histopathological features of pericardial tuberculosis and leads to a decrease in the sensitivity of the test. In areas which have a high prevalence of tuberculosis, the combination of a sensitive test such as adenosine deaminase, chest X-ray and clinical features has a higher diagnostic efficiency than pericardial biopsy in diagnosing tuberculous pericarditis.