Expanding The Phenotype Of Hyper-IgE Syndrome: Heterozygous Variant In IL6ST With Elevated Serum IgE And Isolated Abscesses

This case study presents a 15-year-old male with persistent skin abscesses and elevated serum IgE levels, suggesting a diagnosis of hyper-IgE syndrome (HIES) due to a heterozygous variant in the extracellular domain of IL6ST. This variant, c.1405G>C (p.Asp469His), is not found in population databases and represents a potential expansion of the known phenotype for autosomal dominant HIES, as isolated abscesses without other common HIES symptoms have not been previously reported. The study highlights the need for further research to understand the implications of extracellular IL6ST variants in HIES.