Erythema nodosum and pyoderma gangrenosum in 50 patients with Crohn's disease

Erythema nodosum and pyoderma gangrenosum may occur in Crohn's disease. In the present evaluation of consecutive patients with Crohn's disease spanning more than two decades, erythema nodosum was seen in 45 patients and pyoderma gangrenosum was seen in seven patients. Forty-one of 566 women (7.2%) and nine of 449 men (2.0%) were affected. Of these, 45 (4.4%) had erythema nodosum and seven (0.7%) had pyoderma gangrenosum, including two (0.2%) with both dermatological disorders at different times during their clinical courses. Recurrent erythema nodosum was also detected in nine patients (20%) including eight women, while recurrent pyoderma gangrenosum was seen in two patients (28.6%). There was an age-dependent effect on the appearance of erythema nodosum in women, with the highest percentages seen in those younger than 20 years of age. Detection rates for erythema nodosum in women only approached the low men's rates in Crohn's disease at older than 40 years of age. Most patients with these dermatological disorders had colonic disease with or without ileal involvement as well as complex disease, usually with penetrating complications. The present study documents a sex-based and age-dependent effect on the clinical expression of erythema nodosum in Crohn's disease. This suggests that some components of the inflammatory process in Crohn's disease may be modulated by estrogen-mediated events, particularly in adolescents and young adults.