<prompt> Which of the following is least likely to cause constrictive pericarditis?Tuberculous pericardial effusionStaphylococcal effusionPost cardiac surgeryAcute rheumatic fever  <response>: Ref Harrison 19 th ed pg 1575 When pericarditis occurs in the absence of any obvious underlying disorder, the diagnosis of SLE may be suggested by a rise in the titer of antinuclear antibodies. Acute pericarditis is an occasional complication of rheumatoid ahritis, scleroderma, and polyaeritis nodosa, and other evidence of these diseases is usually obvious. 