Kikuchi-Fujimoto Disease as the Initial Presentation of Dermatomyositis

BACKGROUND: Kikuchi-Fujimoto Disease (KD) is a rare necrotizing lymphadenitis that is often self-limiting but occasionally associated with autoimmune conditions. Dermatomyositis is an autoimmune inflammatory myopathy that typically presents with proximal muscle weakness and a characteristic skin rash. In this report, we present a unique case of KD, the first documented association worldwide as the initial manifestation of dermatomyositis, highlighting the rarity and novelty of this case. CASE PRESENTATION: A 30-year-old Saudi female presented with a persistent fever, cervical lymphadenopathy, and significant weight loss. A lymph node biopsy confirmed the diagnosis of KD. Despite the initial steroid therapy, her symptoms recurred, prompting further investigation, which revealed elevated muscle enzyme levels, myopathic changes on electromyography, and MRI evidence of inflammatory myositis. The clinical presentation, combined with a heliotrope rash, confirmed the diagnosis of dermatomyositis. The patient responded well to pulse steroids, intravenous immunoglobulin, and rituximab, achieving remission and successfully tapering off corticosteroids. She is currently under regular follow-up care at a rheumatology clinic and has been in remission for the past eighteen months. CONCLUSION: This case highlights the importance of considering underlying autoimmune diseases, such as dermatomyositis, in atypical refractory KD. Early recognition and tailored immunosuppressive therapy are crucial to achieve optimal outcomes.