Food protein-induced enterocolitis and enteropathy — formative SAQs

SAQ 1 — The recurrent delayed vomiting collapse (10 marks, 15 minutes)

Prompt: A 7-month-old is brought to the emergency department pale, lethargic and vomiting repetitively. Two hours earlier the child ate rice cereal for the second time; the identical pattern occurred two weeks ago after rice. There is no urticaria, wheeze or swelling. Outline your diagnosis, the criteria that support it, the dangerous mimics to exclude, and your immediate management. ^[1]

Model answer

• Diagnosis: acute food protein-induced enterocolitis syndrome (FPIES) to rice, a non-IgE-mediated, cell-mediated food allergy. The clue is the delayed, repetitive vomiting one to four hours after a trigger food, recurring with the same food, with pallor and lethargy and no classic IgE-mediated skin or respiratory features. ^{[1] [2]}
• Criteria: the 2017 international consensus major criterion is vomiting one to four hours after ingestion without classic IgE features. Support with the minor criteria present here — a repeat reaction to the same food, lethargy, pallor, and an emergency presentation — of which three or more are required. ^[1]
• Mimics to exclude: sepsis (do a septic screen on a first or atypical presentation), intussusception and appendicitis, and, in the premature or very young infant, necrotising enterocolitis; the recurring food-timed pattern and the sterile cultures point to FPIES. ^{[1] [11]}
• Immediate management: assess airway, breathing and circulation; secure intravenous access; send a blood gas, full blood count, electrolytes and glucose; give repeated 20 mL/kg boluses of isotonic crystalloid until perfusion is restored; give intravenous ondansetron for ongoing vomiting and consider a single dose of methylprednisolone; correct acid-base and electrolyte disturbance; observe until the child is stable. ^{[1] [8]}
• Disposition: admit the dehydrated or acidotic child; provide strict avoidance of rice and its cross-reactive grains, a written FPIES action plan, and referral for a medically supervised oral food challenge to confirm and to test tolerance. ^[1]