SCREENING FOR HEREDITARY ANGIOEDEMA IN INFANCY

Abstract

Introduction Hereditary angioedema (HAE) can be difficult to diagnose in infancy because C1 esterase inhibitor levels and function do not reach normal values until about one year of age. We describe a case of a 4-month-old boy who required screening for HAE. Case Description Patient is a 4-month-old boy who presented for screening for HAE because both father and grandfather have HAE. Patient has not had any symptoms of angioedema. No testing was done at the initial visit due to high rates of false positives in infancy. The patient was monitored regularly throughout his first year of life for any symptoms of HAE. At one year of age, testing was performed which showed C1 esterase level of 15 mg/dL (21-39) and function of 61% (normal >67, equivocal 41-67, abnormal Discussion Family members of those with HAE should be screened for HAE. C1 esterase inhibitor level and function is typically lower in infants than in adults, leading to false positive results in infancy. This makes it difficult to diagnose HAE in infants and no clear consensus exists on how to appropriately screen these individuals. For our patient, we chose to follow regularly until he was one year of age and advised his family to contact us if he had any symptoms or required any surgical procedure. At one year of age, testing revealed he had type 1 HAE. We prescribed plasma derived C1 inhibitor concentrate, which is the only approved medication for acute treatment of HAE in children under 12.