How to manage a patient with anorexia and bulimia and a BMI of 17?

Management of a Patient with Anorexia, Bulimia, and BMI of 17

A patient with both anorexia and bulimia with a BMI of 17 requires immediate multidisciplinary treatment with consideration for a higher level of care, as this combination of eating disorders significantly increases mortality and morbidity risk. 1

Initial Assessment and Risk Stratification

Medical Evaluation

• Vital signs: Check for bradycardia, hypotension, hypothermia
• Laboratory tests: Complete blood count, comprehensive metabolic panel, electrolytes (particularly potassium due to purging behaviors)
• ECG: Assess for QT prolongation, arrhythmias
• Physical examination: Look for signs of malnutrition, lanugo, Russell's sign (calluses on knuckles from self-induced vomiting)

Psychiatric Evaluation

• Assess for:
  • Severity of food restriction and purging behaviors
  • Comorbid conditions (depression, anxiety, OCD)
  • Suicidal ideation
  • Understanding of illness and willingness to receive help

Treatment Approach Decision

Criteria for Inpatient Treatment

• BMI <16 kg/m² (patient's BMI of 17 is borderline)
• Moderate-to-severe bulimia nervosa with frequent purging
• Medical instability (abnormal vital signs, electrolyte disturbances)
• Failed outpatient treatment
• Suicidal ideation 1

Outpatient Treatment (if medically stable)

• Weekly weight monitoring with target weight goals
• Nutritional rehabilitation with structured meal planning
• Careful monitoring for refeeding syndrome
• Regular laboratory monitoring 2, 1

Specific Treatment Components

Nutritional Rehabilitation

• Set individualized weight goals based on height, age, and premorbid weight
• Target weekly weight gain of 0.5-1 kg in outpatient setting
• Gradual increase in caloric intake to avoid refeeding syndrome
• Monitor for complications: hypokalemia, hypochloremic alkalosis from purging 2

Psychotherapy

• First-line treatments:
  • Family-Based Treatment (FBT) for younger patients
  • Cognitive-Behavioral Therapy (CBT) for bulimia symptoms
  • Interpersonal Therapy (IPT) as an alternative 1

Pharmacotherapy

• For bulimia symptoms: Fluoxetine 60 mg daily (FDA-approved) 1, 3
  • Start at 20 mg/day and titrate up over several weeks
  • Maximum dose: 60-80 mg/day
  • Monitor for side effects: anxiety, insomnia, hyponatremia
• No FDA-approved medications for anorexia nervosa 4

Monitoring and Follow-up

• Regular weight checks (weekly initially)
• Frequent laboratory monitoring (electrolytes, renal function)
• Reassess need for higher level of care if:
  • Continued weight loss
  • Worsening purging behaviors
  • Development of medical complications
  • Suicidal ideation 2, 1

Common Pitfalls to Avoid

• Underestimating illness severity - eating disorders have the highest mortality rate among psychiatric disorders
• Focusing solely on weight rather than normalizing eating behaviors
• Inadequate monitoring for medical complications
• Premature discharge from treatment
• Not addressing underlying psychological issues 1

Long-term Management

• Regular reassessment of treatment needs every 3-6 months
• Ongoing psychotherapy to address body image disturbances and fear of weight gain
• Monitoring for relapse, particularly during stressful life transitions
• Addressing comorbid conditions (depression, anxiety, OCD) 2, 1

This patient's combination of anorexia and bulimia with a BMI of 17 represents a serious medical condition requiring careful assessment and comprehensive treatment. While outpatient management may be possible if the patient is medically stable, close monitoring is essential, and hospitalization should be strongly considered if there are any signs of medical instability or if outpatient treatment fails.