A rare case of latent syphilis-induced complete heart block without aortic root dilatation

SESSION TITLE: Cardiovascular Disease Case Report Posters 21 SESSION TYPE: Case Report Posters PRESENTED ON: 10/09/2023 02:10 pm - 02:55 pm INTRODUCTION: Syphilis is caused by the spirochete Treponema pallidum and can be classified into primary, secondary, tertiary, and latent stages. If left untreated, syphilis can lead to irreversible organ damage, most commonly of the cardiovascular and nervous systems. We present a rare case of latent syphilis induced heart block without aortic root dilatation. CASE PRESENTATION: A 69-year-old male with a history of multiple myeloma presented with bilateral lower extremity pain and cough. Physical exam revealed decreased breath sounds and tenderness of the thighs. Labs revealed pancytopenia and AKI while imaging was negative for acute pathology. Upon admission he became febrile; cultures and labs were redrawn. Respiratory panel was positive for Rhinovirus and procalcitonin began to uptrend so meropenem and doxycycline were started for broad-spectrum coverage. Fevers persisted despite antibiotics; cultures remained negative. Human immunodeficiency virus, urine legionella, and streptococcal, mycoplasma, and chlamydia antigens were negative. Fluorescent treponemal antibodies (FTA-ABS) were positive so intramuscular penicillin G 2.4 million units was given. Patient then reported lethargy and was found to have bradycardia on exam. Electrocardiogram revealed new complete atrioventricular (AV) block compared to previous sinus rhythm. Tick disease panel was negative. Echocardiogram revealed no significant findings. Patient received transvenous pacing and was transferred to a tertiary center for pacemaker placement. 24 hours after arrival, the patient went into cardiac arrest and expired. DISCUSSION: Literature demonstrates a rise in cases of latent syphilis with a reported 30% increase in 2020 compared to 2016 per the CDC. [1] Latent syphilis is classified as early latent (EL) or late latent (LL). Our patient met criteria for LL syphilis as he was asymptomatic with positive serology and no evidence of syphilis obtained within the year. [2] With persistent fevers and new AV block, several etiologies were ruled out with the infectious workup. In addition, the patient was not on AV nodal blockade, and metabolic and autoimmune disorders were ruled out. This led us to hypothesize syphilis was the etiology of the AV block, although latent syphilis traditionally affects the aortic root and coronary arteries predisposing to aneurysms and endocarditis(2). Penicillin once weekly was planned for three weeks however our patient received a single dose before passing away. Earlier detection and treatment of latent syphilis may have prevented complete AV block and subsequent arrest. CONCLUSIONS: In the absence of known conduction system disease, it is important to consider less common causes of new AV block. Syphilitic heart disease infrequently presents with complete heart block which can be lethal. With rising occurrence, vigilance for atypical presentations of syphilis is required to decrease hospitalizations and complications. REFERENCE #1: 1. "Table 19. Unknown Duration or Late Syphilis* - Reported Cases and Rates of Reported Cases by State/Territory and Region in Alphabetical Order, United States, 2016-2020." Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 12 Apr. 2022, https://www.cdc.gov/std/statistics/2020/tables/19.htm. REFERENCE #2: 2. "Syphilis: Treatment and Monitoring." UpToDate, https://www.uptodate.com/contents/syphilis-treatment-and-monitoring. REFERENCE #3: 3. United States Centers for Disease Control and Prevention. Sexually Transmitted Disease Surveillance 2020. https://www.cdc.gov/std/statistics/2020/tables/19.htm (Accessed on April 25, 2022).4. Complete Heart Block Due to Syphilis ALBERT WEINSTEIN, M.D.; R. H. KAMPMEIER, M.D., and T. R. HARWOOD, M.D., Nashville, Tenn https://jamanetwork.com/5. Cardiovascular syphilis-associated acute myocardial infarction: A case report. Medicine (Baltimore). 2021 Feb 19;100(7):e24788. doi: 10.1097/MD.0000000000024788. PMID: 33607833; PMCID: PMC7899849 DISCLOSURES: No relevant relationships by Usman Asif No relevant relationships by Andrew Grees No relevant relationships by Cassidy Guida No relevant relationships by Sukhjeet Kaur No relevant relationships by Elnaz Mahbub No disclosure on file for Aishwarya Ramesh No relevant relationships by Jagraj Singh No disclosure on file for Anthony Vacchio