Interstitial Granulomatous Dermatitis Associated With Ulcerative Colitis: A Rare Cutaneous Manifestation

Interstitial granulomatous dermatitis (IGD) is a rare inflammatory dermatosis that has been associated with several autoimmune conditions, including inflammatory bowel disease. Although cutaneous manifestations are well-recognised in ulcerative colitis, IGD remains an uncommon and under-recognised extraintestinal manifestation that can mimic other inflammatory skin disorders, leading to diagnostic uncertainty. This case discusses a 36-year-old woman with a background of ulcerative colitis who presented with erythematous lesions affecting both forearms. Due to the clinical appearance of the lesions and the patient's underlying inflammatory condition, Sweet's syndrome was suspected. However, after further investigations from the dermatology department, histopathological examination demonstrated features consistent with IGD. The patient was treated with topical corticosteroids, resulting in the resolution of the lesions without recurrence. This case underscores the importance of considering IGD as a differential in patients with inflammatory bowel disease who present with atypical cutaneous lesions and emphasises the role of histopathological examination in establishing the diagnosis and guiding appropriate management.