An Unusual Presentation of Systemic Lupus Erythematosus in a 70-Year-Old Female: A Case Report

Systemic lupus erythematosus (SLE) is uncommon in the elderly and often presents with subtle or atypical features that mimic malignancy, chronic infection, or other autoimmune disorders. We report a 70-year-old previously healthy woman with six months history of constitutional symptoms followed by photosensitive macular and malar rashes, generalized non-tender lymphadenopathy, and pancytopenia. Extensive infectious and malignant workup was negative. Autoimmune evaluation revealed ANA positivity (1:320, homogeneous), low complement levels, and positive anti-Ro and anti-Smith antibodies, confirming late-onset SLE despite negative anti-dsDNA. Her skin biopsy was also highly suggestive of subacute cutaneous lupus erythematosus. Treatment with prednisolone and hydroxychloroquine led to clinical and hematologic improvement with imaging evidence of marked resolution of lymphadenopathy. This case illustrates the diagnostic complexity of late-onset SLE and highlights the importance of considering SLE in elderly patients presenting with unexplained constitutional symptoms, lymphadenopathy, cutaneous manifestations and cytopenia.