[Histiocytic necrotizing lymphadenitis: report of three cases]

Histiocytic necrotizing lymphadenitis (HNL), also known as Kikuchi 5 disease is a rare condition of unknown etiology. Patients present with cervical lymph node enlargement, fever and malaise. The diagnosis is made by excision biopsy. However, this entity must be distinguished from both reactive processes and malignant tumors such as lymphoma. The clinical course is self limited with spontaneous resolution within a few months. We report three patients with the disease. A 37 year-old woman with a 4 months history of a painless submaxillary mass of 2.5 cm diameter, attached to the deep tissues of the neck. The mass was excised and the biopsy report was HNL. After 26 months of follow up, the patient is asymptomatic. A 30 year-old woman with a history of 2 months of a painless lateral cervical mass and aspiration biopsy was reported as suspicious for lymphoma. An excision biopsy was performed, that was reported as HNL. In both patients, lymphoma was ruled out by immunohistochemistry. A 33 year-old woman with a 3 weeks history of an asymptomatic lateral cervical mass. Biopsy was reported as HNL. This condition must be included in the differential diagnosis of cervical asymptomatic masses. The clinician must be aware of it to avoid long-term, costly treatments.