603. Misdiagnosis of Lyme Disease in Patients Referred to an Academic Lyme Center

Abstract

Abstract Background Confusion and controversy surround various aspects of Lyme Disease (LD) including diagnosis. Typically, the diagnosis of LD is based on tick exposure, clinical history, exam, and laboratory testing. Laboratory testing and interpretation can be confusing, difficult, and a source of misdiagnosis. Methods One hundred and fifteen records of patients referred to the Integrated Lyme Program at University of Maryland for evaluation of LD were analyzed. All patients underwent initial evaluation by Infectious Disease (ID) physician who made a determination regarding Lyme diagnosis based on history, exam, epidemiologic risk factors and laboratory test results. Pt were determined to have one of the following diagnoses: 1) Acute LD 2) Past LD 3) Post Treatment Lyme Disease Syndrome (PTLDS) 4) Misdiagnosed LD. Data was also collected on reasons for misdiagnosis based on record review, referral information and patient reported information. Results We evaluated 115 patient records from our Lyme Program Registry. There were 78 female (68%) and 37 males (32%). The mean age was 46 years (range 19 to 83). Of the 115 records analyzed, there were 8 (7%) patients with acute Lyme disease; 38 (33%) patients with past Lyme disease , 3 (2.6%) patients with PTLDS and 93 (81%) of patients who were misdiagnosed with LD. Patients were misdiagnosed for multiple reasons and by different people. Twenty three percent (21/93) were misdiagnosed based on false positive IGM Western Blot; 16% (15/93) were misdiagnosed based on misread IGG Western Blot and 14% (13/93) were misdiagnosed based on unconventional Lyme test. The remainder were misdiagnosed based on symptoms. Forty two percent (39/93) were misdiagnosed by PCP; 4.3%(3/93) were misdiagnosed by Urgent/Emergent care physician and 31% (29/93) were misdiagnosed by physicians’ self-referred as Lyme Literate Medical Doctor. The remainder were incorrectly self-diagnosed by patients based on symptoms. Conclusion Misdiagnosis of patients referred to Lyme Center is common and due to various reasons including misinterpretation of laboratory Lyme testing by healthcare providers and misinterpretation of symptoms by patients. Disclosures All Authors: No reported disclosures