A rare cause of axillary lymphadenopathy: Kikuchi's disease.

To cite: Mannu GS, Ahmed F, Cunnick G, et al. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/ bcr-2013-203100 DESCRIPTION A healthy 19-year-old woman presented to her general practitioner with a 2-month history of a right axillary lump. There were no breast lesions and a general clinical examination was unremarkable. The lump was thought to be an enlarged lymph node so the patient was given several courses of antibiotics with little benefit. Tests for lymphoma and systemic lupus erythematosis (SLE) were negative. The patient was subsequently referred to the breast clinic where an ultrasound scan showed two lymph nodes of indeterminate appearance. As fine needle aspiration of one of these demonstrated reactive changes, an excision biopsy was performed. This showed the necrotising histiocytic lymphadenitis (figure 1) seen in Kikuchi’s disease. The patient’s symptoms subsequently resolved with conservative management. Kikuchi’s disease, otherwise known as Kikuchi’s histiocytic necrotising lymphadenitis, is a rare selflimiting condition presenting with cervical lymphadenopathy and fever. It is unusual for it to present with axillary lymphadenopathy as in this case. It is more common in young women and in people of Asian ethnicity. Laboratory findings are usually unremarkable other than leukopenia or a raised erythrocyte sedimentation rate in some cases. Although it is a self-limiting condition, lymph node biopsy is required to exclude other causes of lymphadenopathy such as lymphoma or viral infections. Microscopically, the affected lymph nodes show a histiocytic infiltrate with discrete foci of paracortical necrosis and abundant karyorrhectic debris. Neutrophils and plasma cells are virtually absent (figure 2). The condition can be difficult to distinguish from SLE and so serological tests are helpful. The treatment is supportive and symptoms commonly resolve within a few months.