# An Atypical Pediatric Dermatologic Presentation Unmasking an Unexpected Systemic Diagnosis: A Diagnostic Challenge

## TL;DR

A 13-year-old boy with unusual skin and joint symptoms was found to have HIV and rare IgA vasculitis, highlighting the need for broad differential diagnosis in complex pediatric cases.

## Contribution

This case report highlights the diagnostic challenge of atypical pediatric presentations leading to an unexpected HIV diagnosis.

## Key findings

- A 13-year-old male presented with persistent bilateral pedal edema and bullous lesions resistant to antibiotics.
- HIV-1 was diagnosed via serologic testing, with non-perinatal transmission confirmed.
- Atypical IgA vasculitis was concurrently diagnosed, emphasizing the need for broad differential diagnosis in complex pediatric cases.

## Abstract

Dermatologic and musculoskeletal presentations in pediatric patients can pose significant diagnostic challenges, particularly when findings are atypical, persistent, and resistant to therapy. We present a diagnostically complex case of a 13-year-old male with a history of multiple psychiatric comorbidities who developed progressive bilateral pedal edema, bullous lower extremity lesions with excoriations, and severe pain, all symptoms seemingly refractory to antibiotics. Despite initial concern for skin and soft-tissue infection, symptoms persisted, prompting inpatient evaluation and an expanded serologic workup. Screening for immunologic and infectious causes, including human immunodeficiency virus (HIV) and sexually transmitted infections, revealed a new diagnosis of HIV-1 acquired through non-perinatal transmission. The patient was concurrently diagnosed with atypical IgA vasculitis, raising consideration of infectious versus drug-related triggers based on his medication regimen. Although vasculitis is uncommon in HIV-positive patients, and IgA vasculitis is even rarer, this case emphasizes the importance of a broad differential diagnosis in pediatric patients with multisystem involvement. Ultimately, close attention to atypical presentations can ensure timely diagnoses and better care for patients facing similarly complex conditions.