Case Report: A Pediatric Case of Autosomal Dominant HAE

A new case has been reported of a child determined to have a new deleterious serine protease inhibitor 1 (SERPING1) gene variant, ultimately leading to hereditary angioedema (HAE).

The case, published in the Annals of Allergy, Asthma, & Immunology, had a successful outcome with prophylactic plasma-derived concentrate of C1 esterase inhibitor.

“Type I hereditary angioedema (HAE) is characterized by recurrent episodes of swelling of the skin, gastrointestinal tract, and upper airway,” the authors wrote. “Here we present a child with chronic abdominal pain who was found to have a novel deleterious variant in the serine protease inhibitor 1 [SERPING1] gene resulting in autosomal dominant [AD] HAE.”

The patient was a 9-year-old boy who had a history of pediatric acute onset neuropsychiatric syndrome, febrile illnesses, and immunoglobulin (Ig) A deficiency who presented with chronic pain in the abdomen and headaches. He had no family history of angioedema, but blood tests revealed low C4 complement levels of 7 mg/dL; therefore, he underwent a workup for HAE.

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Genetic analyses showed a “likely pathogenetic” SERPING1 variant c.1481G>A (p.Arg494Gln) and low C1 esterase inhibitor protein. Immunohistochemistry showed partial IgA deficiency and he was negative for anti-IgA antibodies.

The patient was administered prophylactic plasma-derived concentrate of C1 esterase inhibitor with an excellent response and his symptoms resolved.

The authors recommend that even in the absence of a personal or family history of HAE clinicians consider the disease in the differential diagnosis of patients with chronic abdominal pain. They also note the deleterious effect of the c.1481G>A SERPING1 gene variant, as confirmed by the combination of low levels of C4 complement and reduced C1 esterase inhibitor.

Reference

Hauk S, Fowler S, Hannett K, Trotto N, McGoey B, Ravell J. Type I hereditary angioedema associated with SERPING1 gene mutation. Ann Allergy Asthma Immunol. Published online November 8, 2022. doi:10.1016/j.anai.2022.08.919