Challenges in diagnosis: A case of Kikuchi-Fujimoto disease presenting with lymphadenopathy

Background: Kikuchi-Fujimoto disease (KFD) is a non-malignant and self-limiting condition, characterized by localized swelling of the cervical lymph nodes. It is typically accompanied by a mild increase in body temperature and excessive sweating during the night. Case Presentation: This case report presents a case of a 45-year-old male presented with a history of moderate, episodic fever with chills, body aches, fatigue, and myalgia for 6 weeks. The fever was unchanged in intensity. The patient denied respiratory or gastrointestinal symptoms, maintained a normal appetite, and did not experience weight loss. Notably, there were no exacerbating factors, and symptoms were relieved by medication. His medical history included smoking 20 cigarettes daily for 20 years, with no known chronic conditions or significant family history apart from maternal diabetes and hypertension. Physical examination revealed stable vital signs and multiple mobile, non-tender lymph nodes in the left lower cervical region. Imaging, including chest X-ray, abdominal ultrasound, and CT scan, indicated multiple enlarged lymph nodes and suspicious findings in the duodenum and liver. Esophagogastroduodenoscopy revealed grade B esophagitis, erosive antral gastritis, and mild duodenitis, with biopsies indicating reactive lymphadenitis consistent with KFD. The diagnosis of KFD was confirmed through lymph node biopsy, showing characteristic histopathological features and negative special stains for microorganisms. The patient was managed with prednisolone and fluconazole for esophageal candidiasis. Follow-up revealed resolution of fever and lymphadenopathy, with the patient being clinically stable. Conclusion: This case highlights the clinical presentation, diagnostic challenges, and effective management of Kikuchi-Fujimoto Disease in a middle-aged male. This emphasizes the need to consider KFD in the differential diagnosis of prolonged fever and lymphadenopathy, especially when systemic symptoms and positive markers for infections or autoimmune diseases are absent.