The incidence and clinical characteristics by gender differences in patients with Kikuchi-Fujimoto disease.

Kikuchi-Fujimoto disease (KFD) is a rare, self-limiting disorder that typically affects the cervical lymph nodes (LNs). Although initially described in young women, KFD also occurs in men. There are no reports on the clinical manifestations and characteristics of male KFD patients. Therefore, this study was conducted to assess the incidence of KFD among males, as well as the most frequent clinical characteristics of these patients. A retrospective, cross-sectional study was performed at a tertiary hospital of patients pathologically confirmed as having KFD from LN biopsy specimens. Clinical and laboratory data, and treatment outcomes of the enrolled patients, were analyzed by gender. A total of 254 patients diagnosed with KFD were enrolled. There were 189 females and 65 males (2.9:1). The mean age was 32.6 ± 11.3 years. Compared to the female patients, the males had more frequent manifestations of fever (48% vs 67%, P = 0.008), headache (9% vs 20%, P = 0.013), bilateral lymphadenopathy (31% vs 46%, P = 0.029), thrombocytopenia (14% vs 29%, P = 0.014), elevated C-reactive protein (CRP) (35% vs 78.4%, P < 0.001), elevated liver enzymes (15% vs 41%, P < 0.001), and elevated lactate dehydrogenase (LDH) (61% vs 80%, P = 0.021). Male patients had fewer autoimmune features (9% vs 2%, P = 0.043) and fewer positive antinuclear antibodies (32% vs 10%, P = 0.006). In this study, 25.6% of the enrolled patients were male, with a 2.9:1 female-to-male sex ratio. Male patients showed a distinctive profile characterized by a higher frequency of fever, headache, bilateral lymphadenopathy, and thrombocytopenia, as well as elevated liver enzymes, CRP, and LDH.