Sub-Acute Cutaneous Lupus Erythematosus Following Nitrofurantoin: Causative or Coincidental?

A 70-year-old woman developed sub-acute cutaneous lupus erythematosus (SCLE) after taking nitrofurantoin for recurrent urinary tract infections, presenting with a rash and alopecia. Treatment with topical steroids and hydroxychloroquine was effective, and immunological tests and a skin biopsy confirmed the SCLE diagnosis. This case suggested a potential causal link between nitrofurantoin and SCLE, emphasizing the importance of monitoring patients on long-term nitrofurantoin for serious adverse effects like drug-induced lupus. After one year, the patient did not develop systemic lupus erythematosus.