Kikuchi disease: 18F-FDG positron emission tomography/computed tomography of lymph node uptake

This study evaluated (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings in patients with Kikuchi disease (KD), or histiocytic necrotizing lymphadenitis.

We evaluated the (18)F-FDG PET/ CT findings of seven patients (one man, six women) with KD, ranging in age from 23 to 66 years (mean 36 years). All the patients had been diagnosed based on the pathological findings of a biopsy and clinical course.

The maximum standard uptake values (SUVmax) of FDG uptake in affected lymph nodes were 2.05-13.94 (mean +/- SD, 6.25 +/- 3.32). In all the patients but two, the lymph nodes with the SUVmax were located in the neck. All the lymph nodes had a diameter of <30 mm. In nonneck regions, the SUVs of the swollen lymph nodes tended to indicate lower uptake.

FDG-PET/CT was capable of visualizing general regions containing lymph nodes and was useful for making clinical decisions as to biopsy sites. Together with the physical findings, consideration of the distribution and size of the affected lymph nodes, as shown using FDG-PET/CT, may be useful for suggesting the possibility of KD. KD should be considered in the differential diagnosis of FDG-avid lymph node lesions.