You are correct. Russell sign, named after psychiatrist and eating disorders clinic founder Gerald Russell, is seen in pts w/ bulimia nervosa and the bulimic subtype of anorexia nervosa. The presence of abrasions or calluses on the dorsum of the hand (usually the knuckle) results from pts using their fingers to irritate the back of the mouth to induce vomiting; the incisor teeth and mouth acids cause skin irritation. Hypokalemia is virtually pathognomonic of vomiting in pts w/ eating disorders and may be reflected as flattened T waves on ECG. Bulimia nervosa responds to a version of cognitive-behavioral therapy specifically adapted for this dz.

BMJ 2009;338:b980