Kikuchi-Fujimoto disease: the great masquerader: a rare case report

Abstract

Clinical Presentation

Kikuchi disease (KD), also known as Kikuchi-Fujimoto disease or histiocytic necrotizing lymphadenitis, is a self-limiting cause of cervical lymphadenopathy. The prime cause may be infection, mostly being viral or autoimmune but the exact mechanism remains unclear. This case is challenging because of the misconception in view of the nonspecific clinical features leading to potential delay in diagnosis and irrelevant treatment costs.

A 49-year-old Asian woman reported fever, pain, and multiple swellings in the right side of her neck. Clinical findings of the case suggested further investigation through computed tomography evaluation. Multidetector computed tomography study with contrast revealed multiple pathologically enlarged lymph nodes in the right neck, with central low attenuation/necrosis, rim enhancement, and perinodal infiltration. Mild fat stranding and edema around the lymph nodes and in the fascial spaces of the right neck are present. Largest lymph nodes measured up to 14 mm in the right level 1B and level 2 regions.

Differential Diagnosis

Differential diagnosis included non-Hodgkin lymphoma, tuberculosis adenitis, systemic lupus erythematous, cat scratch disease, or toxoplasmosis.

Diagnosis and Management

Acid-fast bacilli and Grocott methenamine silver stains were negative for mycobacterial and fungal organisms respectively. Ultrasonography-guided right cervical lymph node biopsy revealed cylindrical cores of tissue predominantly consisting of necrosis with few viable lymphocytes. Focal histiocytes were present at the junction of necrosis. The features were consistent with necrotizing lymphadenitis/Kikuchi disease. The patient was managed supportively with nonsteroidal anti-inflammatory drugs and is currently being followed up.

Conclusion

This intriguing case of an uncommon cause of right tender lymphadenitis prompts investigation and recognition by physicians, radiologists, and pathologists for commonly misdiagnosing as lymphoma. Awareness of greater prevalence among East Asian populations and highlighting the self-limiting nature of Kikuchi disease may help for more accurate diagnosis and management of the disease.