A case of Kikuchi's disease with lymphadenopathy in the parotid gland

Abstract

Kikuchi's disease, also known as histiocytic necrotizing lymphadenitis, is an inflammatory disease. Typically, this disease affects young women, presenting with a fever and painful cervical lymphadenopathy as the main symptoms. We experienced a case of atypical Kikuchi's disease in the parotid gland and superior deep cervical lymph nodes of an elderly man. A 66-year-old man was admitted to our hospital complaining a mass in front of his ear and superior neck pain on the left side. Imaging studies showed a parotid tumor and multiple lymphadenopathy in the upper and middle inner deep cervical region on the left side. In all lesions, the ADC (apparent diffusion coefficient) value was low on magnetic resonance imaging. Malignant disease, such as lymph node metastasis of parotid carcinoma, malignant lymphoma, or a combination of parotid tumor and inflammatory lymphadenopathy, were considered as the differential diagnoses. Parotid gland superficial lobectomy and a cervical lymph node biopsy were performed. The tissue submitted as a parotid tumor was found to be a parotid lymph node on a histopathological examination, and all of the cervical and parotid lymph nodes were diagnosed with Kikuchi's disease. When diagnosing a parotid mass and/or cervical lymphadenopathy, it is important to consider Kikuchi's disease as a differential diagnosis even when the patient does not show the conventional typical features of Kikuchi's disease.