A rare disorder in an orphan disease: Kikuchi-Fujimoto disease in a young-adult patient with sickle cell anemia.

Kikuchi–Fujimoto disease (KFD) is a rare benign lymphadenopathy, also known as histiocytic necrotizing lymphadenitis [1]. KFD is a self-limited disease that predominantly affects young women and is generally associated with autoimmune pathologies [1]. In October 2013, a 22-year-old North-African female with sickle cell disease (SCD) under hydroxyurea treatment (HU; 20 mg/kg/d) presented with achy, enlarged, and tender left-side lateral cervical lymph nodes without fever and weight loss. The patient also described intense neck pain with head movements and ear-pain. Complete blood count (CBC) showed mild anemia (Hb 10.2 g/dL), normal leukocyte count (6,550/lL) with a relative reduction of total lymphocytes (2,560/lL). Immunophenotyping showed decreased T-lymphocyte count (1,515/lL), increased B-lymphocyte count (816/lL) with a decrease in the T4/T8 ratio (1.31). Erythrocyte sedimentation rate, C-reactive protein, beta-2 microglobulin levels liver, and kidney functional tests were normal. Serologic tests for Epstein–Barr and Citomegaloviruses, HIV, Toxoplasma gondii, Francisella tularensis, Bartonella henselae, Streptococcus pyogenes, and quantiferon-test were all negative. The antinuclear antibodies (ANA) and anti extractable nuclear antigens antibody (ENA) were negative. Ultrasonography of the neck revealed multiple enlarged laterocervical lymph nodes (Image 1A, upper panel) and computed tomograph demonstrated the presence of enlarged lymph nodes in the right axilla (Image 1A, lower panel). Image 1. (A) Upper panel: Color Doppler sonography of the neck. The sonographic scan shows multiple enlarged laterocervical lymph nodes. Lower panel: Contrast enhanced Computed Tomography (CT) of the chest. The CT scan shows enlarged lymph node in the right axilla. (B–E) Lymph node histological and immunohistochemical findings. (B) Typical KFD lesion with a central area of necrosis along with apoptotic bodies and karyorrhectic nuclear debris (HE, 2003 magnification); (C) T-lymphoid cells with cytotoxic CD81 phenotype surrounding necrotic area (2003 magnification); (D) accumulation of CD681 histiocytes (1003 magnification); and (E) CD1231 plasmocytoid dendritic cells at the periphery of the lesions (2003 magnification).