[Metastatic Crohn's disease in childhood]

Crohn's disease (CD) is an intestinal inflammatory disease of unknown origin that is sometimes associated with cutaneous manifestations. These skin lesions are usually nonspecific (erythema nodosum, erythema multiforme and pyoderma gangrenosum) and should be differentiated from the cutaneous lesions corresponding to the typical histological pattern of CD; most of these extend directly from the involved bowel. Noncaseating granulomatous infiltration in skin anatomically distant from areas of gastrointestinal CD and separated by normal skin is extremely rare. This entity, known as metastatic Crohn's disease, can be the first symptom of CD or even more unusually can appear during the course of the disease.We report the case of a 9-year-old boy, previously diagnosed with ileocolic and perianal CD, who had been receiving treatment with mesalazine, prednisone and 6-mercaptopurine for 3 years. He presented with swelling of the penis and scrotum of 2 weeks' evolution, without any other symptoms. Testicular ultrasound showed thickening of the scrotal wall and increased flux at this site. Skin biopsy showed noncaseating granulomas. Results of special staining techniques were negative for the presence of microorganisms. The prednisone dose was increased and metronidazole was added, with noticeable improvement in the lesions. Due to reappearance of cutaneous lesions when the prednisone dose was reduced, the patient currently receives maintenance treatment.