Eating disorders: recognition and medical instability — branching viva

Stem

The examiner will test whether you can recognise an eating disorder under pressure and decide who is medically unstable. [3] [4]

Branch 1 — Recognition

Examiner: A 15-year-old runner fainted at school. She eats only salad and runs before dawn. What is going on, and what do you do first? [3]

Strong answer: Recognise an eating disorder — restriction, driven exercise, syncope and (likely) amenorrhoea — with atypical-anorexia features if the weight is in a non-low band. See her alone, apply SCOFF (two or more positive supports the diagnosis) and a HEEADSSS frame, then immediately quantify instability with weight, vital signs including a standing test, temperature, a 12-lead ECG and bedside glucose. [1] [3]

Branch 2 — Screening

Examiner: Tell me exactly what SCOFF is and when it is useful. [1]

Strong answer: Five questions: do you make yourself Sick?; do you worry you have lost Control over how much you eat?; have you lost more than One stone, about six kilograms, recently?; do you believe you are Fat when others say you are thin?; does Food dominate your life? Two or more is a positive screen and warrants full assessment. It is a primary-care screening tool — a positive screen is not a diagnosis, and a negative screen does not override clinical concern in a clearly unwell adolescent. [1]

Branch 3 — Instability

Examiner: Her resting heart rate is 38 and rises sharply on standing. Is she medically unstable? [4]

Strong answer: Yes. Severe resting bradycardia (under about 40 beats per minute) and a marked postural heart-rate rise are red flags (Junior MARSIPAN framing). The standing test is the most informative and most often omitted sign. She needs admission, continuous cardiac monitoring, a 12-lead ECG for QTc, and electrolyte and glucose assessment before cautious refeeding. [4] [5]

Branch 4 — Red flags and admission

Examiner: List the red flags that mandate admission. [4]

Strong answer: Severe bradycardia, hypotension (under about 80/50), a marked postural heart-rate rise or systolic blood-pressure drop, a prolonged QTc, hypothermia, syncope, hypoglycaemia, and rapid weight loss with food refusal. Any one in a restricting or purging adolescent is a medical admission, not a clinic follow-up. [4] [6]

Branch 5 — Pitfall

Examiner: Her mother says her weight is healthy, so surely she is not that sick? [3]

Strong answer: That is the classic lethal pitfall. Atypical anorexia meets full anorexia criteria at a non-low weight and carries the same bradycardia, prolonged QTc, amenorrhoea, bone loss and refeeding risk. Assess on behaviour and physiology, not size. [3] [6]

Branch 6 — Management and multidisciplinary care

Examiner: You admit her. Talk me through stabilisation and who is involved. [5]

Strong answer: Cardiac monitoring, correct potassium and magnesium to shorten repolarisation, treat hypoglycaemia and give careful fluids to avoid precipitating heart failure in a starved myocardium, then begin cautious refeeding because feeding triggers refeeding syndrome (monitor phosphate). Treatment is multidisciplinary — paediatric medicine for stabilisation, child and adolescent mental health, dietetics, and a therapist trained in family-based treatment, which is first-line for adolescent anorexia. Engage the family as allies. [5] [3]

Examiner extras

• Mortality in anorexia is one of the highest in psychiatry — quote the Arcelus meta-analysis; death from cardiac causes and suicide. [2]
• Always stand the patient up; an ECG is mandatory in any restricting or purging adolescent. [6]
• Atypical anorexia is not milder; family-based treatment is first-line. [3]