RT Journal Article SR Electronic(1) A1 Colomba, Claudia A1 Saporito, Laura A1 Colletti, Pietro A1 Mazzola, Giovanni A1 Rubino, Raffaella A1 Pampinella, Diego A1 Titone, LucinaYR 2008 T1 Atrial fibrillation in Mediterranean spotted fever JF Journal of Medical Microbiology, VO 57 IS 11 SP 1424 OP 1426 DO https://doi.org/10.1099/jmm.0.2008/002162-0 PB Microbiology Society, SN 1473-5644, AB Mediterranean spotted fever (MSF) is a tick-borne acute febrile disease caused by Rickettsia conorii and characterized by fever, maculo-papular rash and a black eschar at the site of the tick bite (‘tache noir’). We describe the case of a 58-year-old man affected by MSF who developed atrial fibrillation. The patient presented himself to the hospital after 7 days of fever, malaise and severe headache. Cardiac auscultation revealed a chaotic heart rhythm and an electrocardiogram confirmed atrial fibrillation with a fast ventricular response. Diagnosis of MSF was made after the appearance of a maculo-papular skin rash, and treatment with oral doxycycline was started. An immunofluorescence antibody test confirmed R. conorii infection. The patient recovered after 7 days of treatment. Cardiac arrhythmia is a rare complication of MSF. Inflammation may play a role in the pathogenesis of atrial fibrillation. R. conorii is an intracellular bacterium which could trigger atrial fibrillation. Our patient was previously healthy and had no reported history of cardiac disease. This suggests that heart function should be monitored in MSF patients even in the absence of underlying risk factors., UL https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.2008/002162-0