Differential Diagnosis for Eating Disorder and Related Conditions
- Single most likely diagnosis
- Other Specified Feeding or Eating Disorder (OSFED): This diagnosis is the most likely given the patient's symptoms, including a BMI of 17.90 kg/m2, avoidance of high-calorie foods, self-induced vomiting at least once a week, and body image disturbance. The patient's behavior does not meet the full criteria for bulimia nervosa due to the denial of binge eating, and while the fear of gaining weight and restrictive eating patterns are similar to anorexia nervosa, the presence of regular self-induced vomiting suggests OSFED.
- Other Likely diagnoses
- Anorexia Nervosa: Although the patient denies binge eating, the restrictive eating patterns, fear of gaining weight, and body image disturbance are all consistent with anorexia nervosa. The self-induced vomiting could be seen as a purging behavior, which is sometimes present in anorexia nervosa.
- Bulimia Nervosa: Despite the patient's denial of binge eating, the regular self-induced vomiting and fear of gaining weight could suggest bulimia nervosa. However, the absence of reported binge eating episodes makes this diagnosis less likely.
- Depressive Disorder: The patient's symptoms of depression, as evidenced by the recommendation for an SSRI, suggest a depressive disorder. Eating disorders often co-occur with mood disorders.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Purging Disorder: Similar to bulimia nervosa but without the binge eating, purging disorder involves regular self-induced vomiting or laxative use to purge, which can lead to severe electrolyte imbalances and other complications.
- Avoidant/Restrictive Food Intake Disorder (ARFID): Although less likely given the patient's fear of gaining weight and body image disturbance, ARFID involves a lack of interest in eating or a fear of eating due to concerns over the taste, texture, or nutritional content of food, which can lead to significant weight loss and nutritional deficiencies.
- Malnutrition and related conditions (e.g., refeeding syndrome): Given the patient's low BMI and restrictive eating, there is a risk of malnutrition and its complications, including refeeding syndrome when nutrition is reintroduced.
- Rare diagnoses
- Pica: Eating non-food substances, which can be associated with nutritional deficiencies.
- Rumination Disorder: Repeatedly regurgitating food, which can be voluntary or involuntary, and may lead to malnutrition and other complications.
- Other rare eating disorders: Such as night eating syndrome, which involves excessive eating at night, or orthorexia nervosa, an obsession with healthy eating that can lead to malnutrition.