Kikuchi-Fujimoto disease in the etiology of fever of unknown origin.

The aim of this study was to emphasize the importance of considering a rare entity, Kikuchi-Fujimoto disease (KFD) in cases presenting with fever of unknown origin to the infectious diseases clinics. A thirty-five year-old woman presented to the Department of Infectious Diseases and Clinical Microbiology, Faculty of Medicine, Ege University with complaints of chills and fever, severe fatigue, weight loss, generalized arthralgia and right axillary swelling. Her medical history revealed that her attacks of fever, severe fatigue and generalized arthralgia had started 2.5 months ago and recurred three times with intervals of 2-3 weeks. Her body temperature was 38 degrees C and a painful lymphadenopathy (LAP) in 1x1 cm size was detected in the right axillary region with deep palpation in her physical examination. The laboratory analysis revealed anemia, leukopenia, a moderate elevation in erythrocyte sedimentation rate, elevated CRP and LDH and a positivity of granular ANA with a titer of 1/80. Multiple lymphadenopathies were detected in the right axillary and right anterior cervical chain by ultrasonographic assessment. The histological examination of the excisional biopsy of the axillary LAP revealed diffuse necrotic areas in the parenchyma of the lymph node. Many macrophages with phagocytic activity with a few immature cells in immunoblast appearance around the necrotic areas with debris were seen. The diagnosis of Kikuchi lymphadenitis (necrotizing lymphadenitis) was made according to these findings. The patient whose complaints recovered without any treatment as in her previous attacks had no recurrence in one-year follow-up. The diseases that should be considered in the differential diagnosis of KFD include all other diseases associated with fever of unknown origin. We conclude that the consideration of KFD particularly in cases of fever of unknown origin presenting with LAP may lead to an earlier biopsy of the reactive appearing lymph node and ultimately a quick and easy diagnosis may be made.