RESUMO
Kikuchi-Fujimoto disease is usually a self-limited cause of lymphadenitis. It is a prevalent disease amongst Asian individuals, but rare in other parts of the world. It affects especially young women, with limited cases described in children. Kikuchi-Fujimoto disease is characterized by focal and tender lymphadenopathy, mostly cervical, accompanied by fever and, less commonly, systemic manifestations. This disease is seldom associated with systemic lupus erythematosus. Herein we describe the case of a previously healthy 7-year-old male patient, who presented with prolonged fever, rash, polyarthritis, cervical lymphadenopathy, hepatosplenomegaly, leucocytosis and markedly elevated inflammatory markers. No changes were seen on the echocardiogram. Antinuclear antibodies were not identified and complement levels were normal. Differential diagnosis included systemic juvenile idiopathic arthritis, infectious diseases and malignancy. Bone marrow aspiration and biopsy were normal. The cervical node biopsy was diagnostic for Kikuchi-Fujimoto disease. Oral corticosteroids were started with notorious clinical response. After one year of follow up, the patient is without medication and remains asymptomatic. This case report shows the often-convoluted course of Kikuchi-Fujimoto disease and diagnostic dilemmas clinicians face when dealing with atypical presentations.