Young Female With Hypereosinophilia, Rash, and Gait Disturbance: A Case Report.

Eosinophilia is known to be associated with a multitude of co-morbidities. However, unexplained eosinophilia poses a diagnostic challenge, and the methods used to investigate unexplained eosinophilia vary from region to region. In this case report, we describe a unique case of a young female presenting with marked eosinophilia to a tertiary hospital in the northeastern United States. Our patient presented with a few weeks of lower extremity rash, gait instability, and new onset marked eosinophilia. We further report the investigations undertaken during the hospitalization to highlight the broad differential diagnoses. Later, we provide a consolidated diagnosis of eosinophilic granulomatosis with polyangiitis (EPGA) based on the clinical context. Our patient was eventually started on a high-dose steroid taper. In the following weeks, while we noted gait improvement, we observed biomarker (eosinophilia) relapse after steroid taper. Depending on symptom progression, we planned for future remission induction with immunomodulatory agents. The report further discusses the pleomorphic presentation of EPGA cases, the natural course of disease, and currently available prognostic indices.