**Core Concept**
Felty syndrome is a severe complication of rheumatoid arthritis (RA) characterized by the triad of RA, splenomegaly, and neutropenia. The presence of neutropenia significantly increases susceptibility to infections due to impaired neutrophil function.

**Why the Correct Answer is Right**
Felty syndrome involves persistent neutropenia, a condition where neutrophil counts are markedly reduced. Neutrophils are key first-line defenders against bacterial infections. This deficiency leads to recurrent and severe infections—especially respiratory and urinary tract infections—making infection frequency a hallmark feature. The syndrome is associated with RA and is linked to progressive immune dysregulation and splenic dysfunction.

**Why Each Wrong Option is Incorrect**
Option B: Rheumatoid vasculitis is a vascular complication of RA, causing skin lesions and organ involvement, but it does not directly cause increased infection risk.
Option C: Episcleritis is a benign, self-limiting inflammation of the eye's episclera, unrelated to infection susceptibility.
Option D: Sjögren syndrome is an autoimmune disorder with dry eyes and mouth, and while it can coexist with RA, it is not associated with increased infection frequency due to neutropenia.

**Clinical Pearl / High-Yield Fact**
In RA patients, the presence of splenomegaly and recurrent infections should raise suspicion of Felty syndrome—especially in those with neutropenia. Prompt evaluation for hematological involvement is critical to prevent life-threatening infections.

✓ Correct Answer: A. Felty syndrome