# Infective endocarditis mimicking antineutrophil-cytoplasmic-antibody-associated vasculitis with glomerulonephritis: a case report

## TL;DR

A case report shows how infective endocarditis can mimic vasculitis, highlighting the importance of accurate diagnosis to avoid harmful treatments.

## Contribution

The novelty lies in presenting a case where infective endocarditis was misdiagnosed as vasculitis due to shared antibody positivity.

## Key findings

- Infective endocarditis can present with antineutrophil cytoplasmic antibody positivity, mimicking vasculitis.
- Misdiagnosis can lead to inappropriate immunosuppressive therapy, which is harmful in endocarditis.
- Accurate differentiation is essential for proper treatment and patient outcomes.

## Abstract

Infective endocarditis occasionally presents with antineutrophil cytoplasmic antibody positivity, leading to diagnostic challenges and confusion, as it can be mislabeled antineutrophil-cytoplasmic-antibody-associated vasculitis. Distinguishing between these two factors is crucial for appropriate management.

In this case report, we describe a 77-year-old White non-Hispanic male patient who initially presented with features suggestive of antineutrophil-cytoplasmic-antibody-associated vasculitis but was ultimately diagnosed with infective endocarditis.

Our findings emphasize the need to rule out infective endocarditis in patients with suspected antineutrophil-cytoplasmic-antibody-associated vasculitis, as it can be the same, and management relies on different lines of therapy. Immunosuppression therapy can lead to devastating effects in patients with infective endocarditis.