Kikuchi's disease of lymph nodes.

OBJECTIVE

To observe and document the clinical features, mode of presentation, histopathological and immunohistochemical features of Kikuchi's disease.

DESIGN

An observational and descriptive study.

PLACE AND DURATION OF STUDY

Histopathology department, Armed Forces Institute of Pathology, Rawalpindi from January, 1997 to December, 2001. SUBJECTS AND METHODS Thirty-one cases of Kikuchi's disease of lymph node were diagnosed during the study period. Hematoxylin and Eosin stained slides were examined and histological features including extent of architectural effacement, zonation, extent of necrosis, and cellular composition were recorded. Special stains and immunohistochemistry was done.

RESULTS

Kikuchi's disease was diagnosed in 31 cases (1.9%) out of 5762 lymph node biopsies received. There were 10 male and 21 female patients. Ten patients were aged between 21 and 25 years (33%). Eight (25.8%) patients were from pediatric age group. Thirty patients (96.4%) presented with cervical lymphadenopathy. Thirteen (41.9%) lymph nodes showed fragmentation, while 8 (25.8%) revealed perinodal spill. Seventeen cases (54.7%) showed more than 50% necrosis. Zonation was seen in 13 (41.9%) cases. Immunohistochemistry showed majority of cells to be histiocytes and T-lymphocytes. Eight cases were followed-up, all of which showed regression of symptoms over 4-8 months.

CONCLUSION

Kikuchi's disease is an uncommon cause of cervical lymphadenopathy in young females. Necrotic areas, karyorrhexis, zonation, absence of neutrophils and predominance of histiocytes with many plasmacytoid monocytes are features that aid in diagnosis. Immunohistochemistry can be used to differentiate it from malignant lymphoma. It is important for clinicians and pathologists to be aware of this entity as it is a benign disorder with a self-limiting course.