Russel's sign: Unilateral hand callosities in bulimia nervosa.

A dermatology consult was sought for a 34-year-old female who presented with repeated vomiting and loss of weight, quantified to be around 13 kgs over the preceding 4 months. Examination revealed strictly unilateral callosities and few superficial erosions over the right distal hand, third and fourth metacarpophalangeal joints, and interphalangeal joints of the second digit, consistent with Russell's sign in bulimia nervosa. History of binge eating followed by purging by forced vomiting was found on dietary history.