# Wolf and the Dagger: A Rare Overlap

## TL;DR

A rare case of a man with both spondyloarthritis and systemic lupus erythematosus highlights the need for better understanding of overlapping autoimmune diseases.

## Contribution

This paper presents a rare clinical case of coexisting spondyloarthritis and systemic lupus erythematosus, emphasizing diagnostic challenges and potential shared mechanisms.

## Key findings

- A 28-year-old male was diagnosed with axial spondyloarthritis and later developed systemic lupus erythematosus symptoms.
- The patient tested positive for anti-nuclear antibodies with multiple specificities.
- Literature review revealed only a few reported cases of this rare overlap.

## Abstract

Systemic lupus erythematosus (SLE) and spondyloarthritis (SpA) are two distinct rheumatological disorders with different pathophysiology. The coexistence of SLE and SpA is very rare and presents unique diagnostic and therapeutic challenges. We present a case of a 28-year-old male who initially presented with inflammatory back pain and characteristic radiologic features, leading to a diagnosis of axial SpA. Subsequently, he developed malar rashes, discoid lupus erythematosus (DLE), and renal involvement. The anti-nuclear antibody (ANA) test by indirect immunofluorescence (IIF) was positive, with multiple antibody specificities on immunoblot. The overlap of SpA and SLE is rare, and a literature review identified only a few case reports. This case highlights the need for heightened clinical awareness and further research into the overlapping mechanisms of SLE and SpA, including potential genetic and immunological factors.