Biological immune-modulator drugs, especially inhibitors of tumor necrosis factor-α, are frequently encountered in modern clinical practice and opportunistic infections are therefore a common concern. Infective pericarditis has been described as a complication of these treatments with possible life-threatening consequences. In similar cases cultures may isolate multiple opportunistic bacteria from the pericardial fluid without specific identification of the responsible germ, representing a problem for targeted antibiotic therapy. We present a case of acute pericarditis evolving in pericardial constriction and cardiac tamponade in a patient treated with adalimumab for psoriatic arthritis overlapping with recurrent polychondritis. Next-generation sequencing allowed the identification of a common oral pathogen as the aetiological agent confirming its role in the identification of species that can be overlooked by common microbiological techniques.
