Anorexia nervosa is an eating disorder in which a person severely limits food because of an intense fear of gaining weight and a distorted body image. Starvation and fluid loss strain the heart and electrolytes, and restarting nutrition too fast can cause refeeding syndrome.
Key symptoms
- Major weight loss and strict control of food intake
- Dizziness or fainting, mostly on standing
- Fatigue, feeling cold and missed periods
- Overexercise, vomiting or laxative use
- Denial of being underweight and fear of weight gain
What you find on exam
- Slow heart rate, low blood pressure and low temperature
- Orthostatic vital signs: a big rise in pulse or drop in pressure
- Weight, height and BMI; dry mouth and poor skin turgor
- Fine body hair, dry skin, cold hands and feet
- Mood and safety screen, including suicide risk
Tests
- Electrolytes with potassium, phosphate and magnesium; glucose
- ECG: slow rate, prolonged QT, arrhythmia
- Kidney function, blood count and liver tests
- Repeat electrolytes daily during the first week of refeeding
Treatment basics
- Admit if very slow heart rate, low pressure, low temperature or abnormal electrolytes
- Careful IV or oral fluids to correct dehydration
- Start nutrition gradually and replace phosphate, potassium and magnesium
- Give thiamine before and during refeeding
- Team care: medical, nutrition and mental health treatment, with family-based therapy for teens
Red flags
- Heart rate under 50 at rest, fainting or arrhythmia
- Low potassium or phosphate, especially after refeeding begins
- Suicidal thoughts or refusal of all food and fluids
Practice it in Making Synapses
Making Synapses cases
Related guides
Sources: NCCPA PANCE Content Blueprint; AAMC Core Entrustable Professional Activities (Core EPAs); Open RN, Nursing Fundamentals 2e. Written by Making Synapses. Making Synapses is not affiliated with these organizations.