Long-term prevention of hereditary angioedema in young children

We present a clinical case of early-onset and severe hereditary angioedema type 1, caused by a pathogenic variant in the SERPING1 gene, in a two-year-old girl. Hereditary angioedema onset occurred at 18 months, which is extremely early for this disorder. The disease onset was characterized by severe clinical manifestations: frequent, debilitating episodes of angioedema of the face, upper and lower extremities (over 8 months, the child experienced 14 episodes of angioedema: 5 in the face and 9 involving peripheral sites). Due to such an early onset and severe course of hereditary angioedema, long-term prophylaxis with lanadelumab was initiated. After more than 5 months of therapy, the child has not experienced a single episode of angioedema, despite exposure to provoking factors. No side effects were observed.

In the literature, only five clinical cases with onset and a definitive diagnosis of hereditary angioedema in children under 24 months of age, with only one of the five requiring long-term prophylaxis. Thus, we present a unique clinical example of the successful use of lanadelumab as long-term prophylaxis in early childhood.