Constrictive pericarditis: Detection of mycobacterium tuberculosis in paraffin-embedded pericardial tissues by polymerase chain reaction

Background: Although the utility of polymerase chain reaction (PCR) for diagnosis of acute pleuro-pericardial tuberculosis has been well established, its use for chronic constrictive pericarditis is yet to be reported. Aims: To define the sensitivity and specificity of PCR for diagnosis of tuberculosis (TB) in patients with constrictive pericarditis. Methods: The medical records of 30 consecutive patients with constrictive pericarditis were reviewed. In addition their historical paraffin-embedded pericardial tissues were used for new histopathologic examination and PCR amplification for Mycobacterium tuberculosis genome. Results: There were 23 males and 7 females with a mean age of 35 ± 19.5 years. The anticipated causes of constriction included idiopathic (n = 21), tuberculosis (n = 5), cardiac surgery (n = 2) and post traumatic (n = 2). PCR became positive in nine patients. Four out of 5 patients with tuberculous granuloma had a positive test result. In addition all 4 patients with non-tuberculous constrictive pericarditis had a negative test result. Therefore considering the presence or absence of granuloma as a diagnostic criteria, the sensitivity and specificity of PCR were 4/5 (80%) and 20/25 (80%), respectively.