In the Lymelight: A Mysterious Case of Heart Block (original) (raw)

Background: We present a case of complete heart block secondary to early disseminated Lyme disease with negative serologies on presentation & positive myocardial biopsy. Case: 62-year-old male presented with a 1 week history of diffuse myalgias, drenching sweats, fever, & chills. Physical exam was unremarkable, EKG showed complete heart block (CHB). Lab work was remarkable for elevated cardiac enzymes. Decision-making: Lyme and tick-borne panels were ordered, & he was empirically started on Ceftriaxone. Initial & subsequent Lyme serologies were negative. Transthoracic Echocardiogram showed diffuse wall motion abnormality concerning for myocarditis, confirmed with a cardiac MRI & unremarkable cardiac catheterization. A myocardial biopsy was performed showing spirochetes within the myocardium. Continued antibiotic therapy reversed his CHB & he was safely discharged on IV antibiotics. Conclusion: This case presents a common disease with atypical serological findings resulting in more advanced diagnostic testing with myocardial tissue biopsy demonstrating spirochetes. While those with early localized disease can be seronegative, it is rare for those with early disseminated disease & organ involvement to have negative serologies. It is reasonable to investigate for Lyme carditis with biopsies in a patient with new onset high grade heart block in the appropriate clinical setting despite negative serologies to help establish a diagnosis and appropriate therapy .