Interstitial Granulomatous Dermatitis: Another Clinical Variant

A 70-year-old female patient presented with an eruption consisting of symmetrically distributed erythematous papules around the umbilicus 1 month after the cessation of adalimumab for the treatment of rheumatoid arthritis. Biopsy of a papule showed an interstitial granulomatous infiltrate in the dermis, without deposition of mucin. The lesions cleared only after re-initiation of treatment 2 months later. Interstitial granulomatous dermatitis is thought to be a distinct histopathological pattern, either drug induced or associated with rheumatoid arthritis or autoimmune collagen diseases. In our case, there was a distinct clinical presentation of interstitial granulomatous dermatitis, composed of symmetrically distributed indurated papules around the umbilicus as well as a mild granulomatous reaction pattern