Kikuchi-Fujimoto Disease, “You probably don’t know me, but you should!”

Learning Objective 1: Recognize the typical presenting features and diagnostic criteria of Kikuchi disease

Learning Objective 2: Understand the treatment and follow up necessary in a diagnosis of Kikuchi disease

Case: The patient is a 32 year old female without significant medical history who presented with right-sided neck swelling and fever for 2 weeks. Two weeks ago, she developed body aches and had a fever of 103.7°F. Patient went to an urgent care and was given clindamycin, naproxen and flexeril for a non-specific throat infection. However, the patient’s symptoms persisted after completion of her antibiotics course and thus, she came to the emergency department. At the time of admission, patient endorsed neck pain with swelling and a headache, but denied any current fever, chills, dysphagia or difficulty breathing. Patient’s physical exam was significant for limited ability to open her mouth, right-sided neck swelling without overlying erythema and right-sided cervical lymphadenopathy and supraclavicular lymphadenopathy. Admission labs, including CBC and BMP, were within normal limits except for non-specific anemia. HIV, QuantiFERON gold, blood cultures and Group A Streptococcus cultures were all negative. CT scan of the neck showed necrotic right-sided lymphadenopathy. Our differential diagnosis included cellulitis, deep tissue neck infection, malignancy, Lemierre’s disease, tuberculosis and Kikuchi’s Disease. She was started on broad spectrum antibiotics, but did not improve after several days. An ultrasound guided fine needle aspiration was performed and cytology demonstrated cells with necrosis, consistent with necrotizing lymphadenitis. She was diagnosed with Kikuchi disease and began treatment with antibiotics and prednisone, with improvement in symptoms at the time of discharge.

Discussion: Kikuchi’s disease is a rare condition that typically presents in young women with localized cervical lymphadenopathy. The enlarged lymph nodes can be tender or firm and painful. Lymphadenopathy is often accompanied by fever and occasionally with upper respiratory symptoms. Up to 40% of patients will develop skin manifestations, most commonly a rash or erythematous macules. Diagnosing Kikuchi’s disease can be challenging and misdiagnosis occurs in up to 40% of patients. Blood work shows non-specific findings such as mild leukopenia, elevated erythrocyte sedimentation rate, anemia, lymphocytosis and thrombocytopenia. Accurate diagnosis of Kikuchi’s disease requires histopathologic examination of the affected lymph node via open excisional lymph node biopsy. The histopathology will exhibit patchy paracortical and cortical necrosis with abundant karyorrhectic debris. Before making the diagnosis of Kikuchi’s disease, it is important to exclude infection and malignancies, including lymphoma, leukemia and adenocarcinoma. Kikuchi’s disease is a self-limiting condition that typically resolves within 6 months. Furthermore, only a 3-4% recurrence rate has been reported. The treatment of Kikuchi’s disease is supportive and aims to alleviate symptoms with the use of analgesics, antipyretics and rest. In the most severe cases, a short duration of oral corticosteroid therapy is recommended. Additionally, while the precise pathophysiology of Kikuchi’s disease is unknown, it has shown to be associated with SLE in up to 25% of cases. Thus, patients diagnosed with Kikuchi’s disease should be monitored and closely followed for the development of SLE or recurrences.