First case of Arcobacter species isolated in pericardial fluid in an HIV and COVID-19 patient with worsening cardiac tamponade

Arcobacter spp. is an emerging pathogen that is increasingly recognized as a cause of human infections. Gastrointestinal manifestations are most described in the case report literature. We present a case of the first documented case of Arcobacter spp. isolated in pericardial fluid in an immunocompromised patient with worsening cardiac tamponade that was successfully managed with an urgent pericardiocentesis and ensuing steroids, antibiotics, and a pericardial drain. The patient had a past medical history of HIV, latent syphilis, PCP pneumonia, ESRD, and hypertension, and presented with worsening dyspnea, subjective fever, myalgias, cough, pleuritic chest pain, and pericardial rub. Diagnostic workup revealed a positive COVID-19 PCR test, elevated high-sensitive cardiac troponins, elevated CRP, elevated D-dimer, and elevated creatinine. An ECG revealed diffuse ST-segment elevation, and imaging showed cardiomegaly with pulmonary vascular congestion and diffuse interstitial edema. Urgent TTE showed a large circumferential pericardial effusion with tamponade physiology present. Culture on aerobic blood agar grew Arcobacter spp. of unknown specific species, and blood cultures were also positive for Arcobacter spp. Treatment involved intravenous meropenem for five days, followed by oral ciprofloxacin, low-dose colchicine, and a tapered dose of ibuprofen. Repeat laboratory data and TTE showed complete resolution of the pericardial effusion and improved left ventricular function. This case highlights the potential for Arcobacter spp. to cause severe infections and the importance of considering it as a possible pathogen in patients with atypical presentations.