A 17 year old girl was brought to the psychiatrist by her mother with history that she was repeatedly found vomiting in the bathroom after taking meals, and that her meal size was extremely small. On examination the BMI of patient was 15 kg/m2 and her knuckles showed callous formation. What is the likely diagnosis?

Anorexia nervosa (DSM-IV-TR specifies two subtypes) Restricting type: during the current episode of anorexia nervosa, the person has not regularly engaged in binge eating or purging behavior (that is, self-induced vomiting, over-exercise, or the misuse of laxatives, diuretics, or enemas). Binge-eating type or purging type: during the current episode of anorexia nervosa, the person has regularly engaged in binge-eating or purging behavior (that is, self-induced vomiting, over-exercise, or the misuse of laxatives, diuretics, or enemas).