Kikuchi–Fujimoto disease presenting as cervical lymphadenopathy mimicking tuberculous lymphadenitis in a young woman with vitiligo: a case report

Kikuchi–Fujimoto disease (KFD) is a rare cause of cervical lymphadenopathy, predominantly seen in young Asian populations with a female preponderance. Although self-limiting in most cases, nonspecific symptoms often create diagnostic uncertainty, especially in countries, where tuberculosis is prevalent, with KFD closely mimicking tuberculous lymphadenitis. KFD has a proposed autoimmune basis and has been well-documented in the literature to be associated with systemic lupus erythematosus (SLE) and other autoimmune disorders. We report the case of a 26-year-old woman with a history of vitiligo who presented with cervical lymphadenopathy and fever, ultrasonically mimicking tuberculous lymphadenitis, and was eventually diagnosed with KFD. A 26-year-old Sri Lankan woman presented with gradually increasing, painless right-sided cervical lymphadenopathy of 1-month duration and fever with chills, night sweats, malaise, fatigue, headache, loss of appetite, and nausea of 1-week duration. On examination, right-sided cervical lymphadenopathy involving the posterior cervical group was observed. Initial investigations revealed mild neutropenia, relative lymphocytosis and elevated ESR, CRP, and LDH levels. Ultrasound revealed level 2–4 cervical lymph node enlargement, suggesting the possibility of tuberculous lymphadenitis. A wire-guided excisional biopsy of the right cervical lymph nodes was performed, and the histopathological findings favored necrotizing lymphadenitis, compatible with KFD, while tuberculosis was excluded. Given the patient’s history of vitiligo suggesting a possible autoimmune predisposition and the well-documented association between KFD and SLE, antinuclear antibody (ANA) testing was performed. The result was 1:80 with positive nuclear patterns, while the cytoplasmic and mitotic patterns were negative and anti-dsDNA antibody testing was also negative. The patient only required symptomatic treatment and she improved clinically on follow-up. Although KFD is self-limiting, it is an important differential diagnosis in patients presenting with cervical lymphadenopathy. Its nonspecific presentation can create diagnostic and treatment uncertainty, as it mimics the features of tuberculous lymphadenitis. In such situations, lymph node biopsy is warranted to arrive at a definitive diagnosis. Owing to its proposed autoimmune etiology, KFD should be suspected, particularly in patients with autoimmune conditions. It is important to screen patients for SLE at the time of presentation and during follow-up.