How I Treat: STAT3 hyper IgE syndrome.

STAT3 hyper IgE syndrome (STAT3-HIES) is a rare inborn error of immunity characterized by chronic eczema, recurrent bacterial and fungal infections, markedly elevated serum IgE levels, and a broad spectrum of skeletal, dental, vascular, and gastrointestinal manifestations. Despite increasing insight into the genetic and immunologic basis of STAT3-HIES, detailed, treatment-oriented guidance for clinical practice remains limited. This article provides a pragmatic management guideline for STAT3-HIES. Clinical and laboratory criteria that should prompt suspicion and select patients for genetic testing are discussed. The therapeutic sections cover acute and prophylactic antibacterial treatment, antimicrobial eradication strategies, antifungal therapy, and immunoglobulin replacement therapy. The treatment of severe eczema, organ-specific care for lung, skeletal, vascular, and dental involvement, vaccinations, and supportive measures including physiotherapy and psychosocial support, as well as approaches to pregnancy management, family planning, and genetic counseling are outlined. Furthermore, hematopoietic stem cell transplantation is discussed. This management-focused approach complements existing reviews and aims to standardize care for patients with STAT3-HIES across centers and disciplines.