Recurrent KCNN4 p.Ser314Pro variant in a child with Gardos channelopathy: a 6-year follow-up

Gardos channelopathy is a rare dehydrated hereditary stomatocytosis caused by gain-of-function KCNN4 mutations. We report a pediatric case due to a recurrent p.Ser314Pro variant, representing the first description outside the Italian population. Over a comprehensive 6-year clinical follow-up, the patient exhibited a stable baseline course punctuated by infection-triggered hemolytic crises, exacerbated by concomitant bronchial asthma. Prospective data demonstrated persistent iron redistribution without systemic overload under conservative management. This case expands the geographic spectrum of the p.Ser314Pro variant, highlights clinical lessons for conservative monitoring, and emphasizes the utility of early next-generation sequencing integration.