- Sho Fukuda: Fmaily Medicine, Unnan City Hospital, Unnan, JPN.
- Kasumi Nishikawa: Family Medicine, Unnan City Hospital, Unnan, JPN.
- Ryuichi Ohta: Community Care, Unnan City Hospital, Unnan, JPN.
Late-onset systemic lupus erythematosus (SLE), defined as SLE developing after age 50, presents distinct clinical features influenced by immunosenescence. Compared to early-onset SLE, it often manifests with nonspecific symptoms such as myositis-like weakness, serositis, and subtle systemic features, complicating timely diagnosis. Given the complexity of comorbidities in elderly patients, distinguishing late-onset SLE from other conditions is critical for appropriate management. We report a case of a 76-year-old man who presented with progressive lower limb weakness and dysphagia. Initial investigations, including laboratory tests, autoantibody profiling, imaging, and nerve conduction studies, led to the diagnosis of late-onset SLE with neuromuscular involvement. The patient exhibited significant systemic symptoms, including muscle weakness, hematologic abnormalities, and pulmonary involvement. Prompt initiation of methylprednisolone pulse therapy followed by intravenous immunoglobulin (IVIG) and oral corticosteroids led to a marked improvement in muscle strength and swallowing function. Within 36 days, he regained independence in activities of daily living (ADL) and was transferred for rehabilitation. This case highlights the diagnostic challenges and therapeutic considerations in late-onset SLE. Myositis and dysphagia, though uncommon, can be prominent in elderly patients, necessitating a high index of suspicion. Early recognition and a multidisciplinary approach are essential for optimizing treatment and functional recovery.