Chronic Infective Endocarditis Linked to Staphylococcus epidermidis Infection of a Pacemaker Lead: A Case Report

The diagnosis and management of pacemaker-related infective endocarditis present significant challenges, with limited available data. Accurately attributing a systemic infection to pacemaker endocarditis can be difficult, particularly in identifying vegetations and obtaining positive blood cultures from patients who have undergone non-specific antibiotic therapy. Moreover, such infections may manifest long after pacemaker implantation. Herein, we present a male patient in his 70s, with a history of pacemaker placement, who was admitted with a three-month history of fever and chills, having already completed two courses of empirical antibiotics prior to admission. Upon hospital admission, he was treated for an infection of unknown origin with intravenous antibiotics. Initial laboratory evaluations indicated leucocytosis and elevated C-reactive protein levels; however, blood cultures and infectious serologies returned normal results. A CT scan of the abdomen and pelvis was deemed unremarkable, and transthoracic echocardiography (TTE) also yielded normal findings. The empirical antibiotic regimen was discontinued, leading to three sets of blood cultures being subsequently positive for coagulase-negative Staphylococcus epidermidis. A transoesophageal echocardiography (TOE) was performed, revealing vegetation on the pacemaker lead. The patient received a triple antibiotic therapy and underwent device removal; subsequent blood cultures were negative following a four-week antibiotic course. A new pacemaker was implanted, and the patient has since remained asymptomatic. This case illustrates that coagulase-negative Staphylococcus epidermidis can infect pacemaker leads even long after installation, potentially leading to an indolent course of infective endocarditis that is difficult to diagnose and manage. Consequently, clinicians should maintain a high index of suspicion for pacemaker infective endocarditis in patients presenting with prolonged fever.