ABSTRACT
With a wide variety of associated diseases, proper diagnosis and treatment of annular rashes can prove clinically challenging. It is essential to remain vigilant of atypical presentations of disease and to complete a comprehensive history, physical, and workup to ensure optimal patient care.
Keywords: annular rash, IgA-vasculitis, cat scratch disease, DRESS syndrome, Henoch Schönlein purpura
INTRODUCTION
Annular lesions—plaques, macules, nodules, or pustules with a ring-like morphology—have been documented in over 30 distinct diseases and disorders. With a wide differential inclusive of both isolated cutaneous disease and systemic disease, proper diagnosis and treatment of an annular rash can prove challenging for clinicians. Extreme variability in symptomology further complicates the diagnostic process [1]. In this report we describe the unique case of a 53-year-old gentleman who presented with a progressing annular rash in the setting of multiple risk factors for systemic diseases. While his initial presentation was concerning for cat scratch disease (Bartonella henselae infection) or drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, thorough evaluation suggested a nonclassical presentation of IgA vasculitis (IgAV). This report will discuss the difficulty in diagnosing and treating annular eruptions and review current literature regarding the epidemiology and presentation of associated disorders.
CASE PRESENTATION