Metastatic Crohn's disease of the forehead

Metastatic Crohn's disease (CD) involves the presence of cutaneous granuloma distant from the intestinal lesions related to the disease, usually observed in colonic CD.

A 35-year-old female with a permanent ileostomy following proctocolectomy for CD presented in 1999 with a 2-month history of an unusual skin lesion of the forehead. A diagnosis of CD of the ileum, colon, and rectum had been made in 1994. In 1997, a proctocolectomy with ileostomy was performed due to fistulizing severe refractory disease. Microscopic aspects of the intestinal lesions showed deep and fissuring ulcers. After surgery, she went into remission, and a small bowel follow-up in 1999 showed no recurrence, when she presented with the skin lesion of the forehead. MICROSCOPIC DATA: Histological analysis of endoscopical and surgical intestinal specimens showed chronic granulomatous inflammation of the ileum, colon, and rectum, confirming the diagnosis of CD. The forehead skin biopsy was examined by three independent histopathologists. The lesion was composed of numerous small granulomas (Ziehl-Nielsen negative), with no foreign bodies, mainly composed of CD68-positive and periodic acid Schiff-negative monocytes. Despite the low number of lymphocytes, the macroscopical and microscopical aspect of the forehead lesion, together with the clinical history, led to a diagnosis of rare metastatic CD of the forehead.

This case report describes the development of an unusual granulomatous skin lesion of the forehead in a patient with established CD showing no postoperative recurrence.