Kikuchi-Fujimoto disease: A comprehensive review

Abstract

Kikuchi-Fujimoto disease, a rare form of necrotizing lymphadenitis, is an uncommon, benign, self-limiting disorder of obscure etiology. It affects mostly young adults of both genders. Clinically, it presents with fever and lymphadenopathy of a firm to rubbery consistency frequently involving cervical lymph nodes while weight loss, splenomegaly, leucopenia, and elevated erythrocyte sedimentation rate feature in severely affected patients. Cutaneous involvement occurs in about 30%-40% of cases as facial erythema and nonspecific erythematous papules, plaques, acneiform or morbilliform lesions of great histologic heterogeneity. Both Kikuchi-Fujimoto disease and systemic lupus erythematosus share an obscure and complex relationship as systemic lupus erythematosus may occasionally precede, develop subsequently, or sometimes be associated concurrently with Kikuchi-Fujimoto disease. It is often mistaken for non-Hodgkin lymphoma while lupus lymphadenitis, cat-scratch disease, Sweet's syndrome, Still's disease, drug eruptions, infectious mononucleosis, and viral or tubercular lymphadenitis are other common differentials. Fine needle aspiration cytology mostly has features of nonspecific reactive lymphadenitis and immunohistochemistry studies usually show variable features of uncertain diagnostic value. Since its diagnosis is exclusively from histopathology, it needs to be evaluated more carefully; an early lymph node biopsy will obviate the need for unnecessary investigations and therapeutic trials. Its treatment with systemic corticosteroids, hydroxychloroquine, or antimicrobial agents mostly remains empirical. The article reviews clinicoepidemiological, diagnostic, and management aspects of KFD from the perspective of practicing clinicians.

Keywords: Cervical lymphadenopathy; Histiocytic necrotizing lymphadenitis; Kikuchi’s disease; Lymphadenopathy; Lymphoma; Systemic lupus erythematosus.

Figure 1

Histopatholgy of a lymph node in Kikuchi-Fujimoto disease. A: Scanner power view of a lymph node in Kikuchi-Fujimoto disease: The pale foci located in between the benign germinal centers are due to the collection of histiocytes(Stain, H&E; × 4); B: Focal areas of the effaced architecture of the lymph node by necrotic foci. Necrosis and pink debris among histiocytes and lymphocytes are typically seen while well-formed granulomas are absent (Stain, H&E; × 10); C: Seen here are focal areas of necrosis without neutrophils and sheets of histiocytes with pale nuclei with a violaceous hue and pink cytoplasm (Stain, H&E; × 40); D: Histiocytes with round-to-sickle-shaped nuclei and typical pink necrotizing nodules mainly composed of histiocytic debris. Neutrophils or suppurative abscesses, a hallmark of suppurative granulomas, are conspicuously absent (Stain, H&E; × 100).

Figure 2

Immunohistochemical staining of lymph node inKikuchi-Fujimoto disease. A: Kikuchi-Fujimoto disease: CD8 immunostaining of lymph node biopsy showing predominantly CD8+ T (cytotoxic) cells highlighting lymphoid cells and large immunoblasts (× 10); B: Kikuchi-Fujimoto disease: Immunohistochemistry of lymph node biopsy showing CD68+ histiocytes in the necrotic areas (× 10).