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Psychiatry ` Psychiatry—Pathology Psychiatry ` Psychiatry—Pathology sEctiON iii 567
Eating disorders Most common in young women.
Anorexia nervosa Intense fear of weight gain, overvaluation of thinness, and body image distortion leading to calorie
restriction and severe weight loss resulting in inappropriately low body weight.
Binge-eating/purging type—recurring purging behaviors (eg, laxative or diuretic abuse, self-
induced vomiting) or binge eating over the last 3 months.
Restricting type—primary disordered behaviors include dieting, fasting, and/or over-exercising. No
recurring purging behaviors or binge eating over the last 3 months.
Refeeding syndrome—often occurs in significantly malnourished patients with sudden calorie
intake insulin PO , K , Mg cardiac complications, rhabdomyolysis, seizures.
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2+
3−
4
Treatment: psychotherapy, nutritional rehabilitation, antidepressants (eg, SSRIs).
Bulimia nervosa Recurring episodes of binge eating with compensatory purging behaviors at least weekly over the
last 3 months. BMI often normal or slightly overweight (vs anorexia). Associated with parotid gland
hypertrophy (may see serum amylase), enamel erosion, Mallory-Weiss syndrome, electrolyte
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disturbances (eg, K , Cl ), metabolic alkalosis, dorsal hand calluses from induced vomiting
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(Russell sign).
Treatment: psychotherapy, nutritional rehabilitation, antidepressants (eg, SSRIs). Bupropion is
contraindicated due to seizure risk.
Binge-eating disorder Recurring episodes of binge eating without purging behaviors at least weekly over the last
3 months. diabetes risk. Most common eating disorder in adults.
Treatment: psychotherapy (first line); SSRIs; lisdexamfetamine.
Pica Recurring episodes of eating non-food substances (eg, dirt, hair, paint chips) over ≥ 1 month that
are not culturally or developmentally recognized as normal. May provide temporary emotional
relief. Common in children and during pregnancy. Associated with malnutrition, iron deficiency
anemia, developmental disabilities, emotional trauma.
Treatment: psychotherapy and nutritional rehabilitation (first line); SSRIs (second line).
Gender dysphoria Significant incongruence between one’s experienced gender and the gender assigned at birth,
lasting > 6 months and leading to persistent distress. Individuals may self-identify as another
gender, pursue surgery or hormone treatment to rid self of primary/secondary sex characteristics,
and/or live as another gender. Gender nonconformity itself is not a mental disorder.
Transgender—desiring and often making lifestyle changes to live as a different gender. Medical
interventions (eg, hormone therapy, sex reassignment surgery) may be utilized during the
transition to enable the individual’s appearance to match their gender identity.
Transvestism—deriving pleasure from wearing clothes (eg, a vest) of the opposite sex (cross-
dressing). Transvestic disorder—transvestism that causes significant distress/functional
impairment. It is a paraphilia (psychosexual disorder), not part of gender dysphoria.
Sexual dysfunction Includes sexual desire disorders (hypoactive sexual desire or sexual aversion), sexual arousal
disorders (erectile dysfunction), orgasmic disorders (anorgasmia, premature ejaculation), sexual
pain disorders (dyspareunia, vaginismus).
Differential diagnosis includes (PENIS):
Psychological (if nighttime erections still occur)
Endocrine (eg, diabetes, low testosterone)
Neurogenic (eg, postoperative, spinal cord injury)
Insufficient blood flow (eg, atherosclerosis)
Substances (eg, antihypertensives, antidepressants, ethanol)
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