CASE SERIES OF INFANTS WITH CHRONIC FPIES

Abstract

Introduction Acute and chronic FPIES are two phenotypes that may occur in the same patient. Due to the heterogeneous presentation and lack of specific biomarkers, the FPIES diagnosis may prove elusive. At our practice, we recently saw three infants with chronic FPIES. Case Description Patient A developed watery/mucousy stools and frequent spit-up on day 3 of life. She was switched from cow's milk formula (CMF) to extensively hydrolyzed formula. Symptoms returned within 3 weeks, and she was hospitalized with dehydration, leukocytosis, thrombocytosis, and metabolic acidosis. Sepsis work-up was negative. Her symptoms resolved with an elemental formula, suggesting FPIES to milk. Patients B and C are twins who presented at 3 weeks. They were fed CMF and had chronic diarrhea, with Patient B requiring intensive care unit admission for dehydration. Symptoms resolved on elemental formula, and FPIES to milk was suspected. They remained asymptomatic until age 11 months, when they were fed cow's milk yogurt and within 3 hours developed repetitive vomiting, followed by diarrhea and dehydration requiring intravenous fluids, confirming the FPIES diagnosis. They similarly developed vomiting and diarrhea one week after introducing soy yogurt, suggesting concomitant FPIES to soy. Discussion Diagnosis of FPIES requires recognition of a constellation of symptoms. In these infants, the diagnosis of FPIES to milk was suggested by chronic diarrhea that resolved with dietary elimination. An acute FPIES reaction in the twins confirmed the diagnosis. The diagnosis of FPIES continues to require a detailed history and keen clinical acumen.