ADVERSE DRUG REACTION TO ALL PROTON PUMP INHIBITORS EXCEPT ESOMEPRAZOLE IN MEDICALLY COMPLEX PEDIATRIC PATIENT

Abstract

Introduction Proton-pump inhibitors (PPIs) are commonly used for treatment of gastroesophageal reflux disease (GERD). PPIs have a favourable safety profile; however, immediate and delayed hypersensitivity reactions have been described. Case Description A six-year-old male with hypomyelination with atrophy of the basal ganglia and cerebellum (HABC) and significant medical complexity including seizure disorder, tracheostomy ventilation, severe GERD, and gastro-jejunostomy feeding, developed a papular acneiform eruption 24 hours after administration of omeprazole, lansoprazole, and rabeprazole. The lesions were not evanescent, and did not respond to antihistamine therapy. Skin testing was negative to omeprazole, lansoprazole, rabeprazole, pantoprazole, and esomeprazole. Esomeprazole was started and tolerated well up to 10mg daily, but the patient developed an upper GI bleed due to duodenal ulcer. He was urgently started on pantoprazole infusion. 24 hours later, he developed generalized coalescent erythematous macules, that resolved within 15 minutes of antihistamine administration. Upon discharge, he was continued on pantoprazole with regular antihistamines. Discussion There are three general patterns of hypersensitivity reactions with PPIs: 1) hypersensitivity to one PPI cross-reacting with all other PPIs; 2) cross-reactivity based on structure analogues; and 3) hypersensitivity to single PPI. Other patterns of reactions have been reported; however, tolerance of esomeprazole alone, with clinical reactions to others is uncommon. This was a medically fragile pediatric patient who required PPIs in both acute and chronic settings. This case demonstrates different clinical reactions in the same patient to different PPIs, and the importance of systematically evaluating all PPI options for safe alternatives.