Kikuchi Disease With Marfanoid Features in a Background of Fever of Unknown Origin.

Kikuchi-Fujimoto disease (KFD) is a self‑limiting necrotizing lymphadenitis that usually affects young women. It can mimic infection, malignancy, or autoimmune disease, which often leads to diagnostic delays. Marfanoid habitus encompasses a constellation of physical traits associated with Marfan syndrome: tall stature, disproportionate limbs, arachnodactyly, joint hypermobility, and chest wall deformities. Co-existence of KFD and prominent marfanoid features has not previously been reported. Based on a structured PubMed/MEDLINE search from database inception through January 2026 using MeSH terms and keyword combinations for "Kikuchi disease," "Marfan syndrome," and "marfanoid habitus," no prior cases describing this overlap were identified. This co-occurrence is clinically relevant because the presence of connective-tissue features may broaden the differential diagnosis, particularly toward autoimmune or heritable syndromes, thereby complicating the evaluation of fever of unknown origin. We describe a Middle Eastern adolescent who presented with fever of unknown origin and necrotic cervical lymphadenopathy. A remittent fever pattern was documented via a fever diary, and physical examination revealed numerous features of marfanoid habitus. Laboratory and imaging investigations excluded infectious, autoimmune, and malignant causes. Excisional lymph‑node biopsy confirmed necrotizing lymphadenitis consistent with KFD. Careful avoidance of empiric antimicrobial therapy in clinically stable patients undergoing evaluation for fever of unknown origin, particularly when atypical physical findings complicate the clinical picture.