Primary Immunodeficiency Disorders and Inborn Errors of Immunity in Saudi Arabia: Current Evidence on Epidemiology, Clinical Impact, and Healthcare System Challenges

The term inborn errors of immunity (IEI) is now widely used to describe many conditions historically known as primary immunodeficiency disorders (PIDs), comprising a heterogeneous group of rare diseases that affect immune system development and/or function and increase the risk of inflammation, infection, immune dysregulation, and malignancy. In Saudi Arabia, the clinical impact of PID/IEI is particularly significant owing to the high consanguinity rates, delayed diagnosis, variable access to specialized immunology services, and limited national records. This narrative review summarizes the available literature on PID/IEI in Saudi Arabia, emphasizing the epidemiology, clinical impact, diagnostic delay, treatment access, healthcare system challenges, and evidence gaps. Relevant literature was identified through searches of PubMed, Scopus, Web of Science, and Google Scholar, supplemented by regional and grey literature, where applicable. The available evidence suggests that PID/IEI remains underrecognized in Saudi Arabia, with published data largely derived from single-center studies, selected cohorts, and hospital-based registries. The current literature highlights important recurring themes, including the significance of consanguinity, the high reported incidence of severe combined immunodeficiency (SCID) in selected studies, timely diagnosis, registry data, and the value of strengthening screening and referral pathways. However, evidence regarding treatment costs, long-term morbidity, quality of life, and regional disparities in access to care remains scarce. Establishing national PID/IEI registries, expanding newborn screening, enhancing primary-care physicians’ awareness, improving genetic diagnostic capacity, and developing clearer referral pathways are important priorities to improve early diagnosis, patient outcomes, and healthcare system preparedness in Saudi Arabia, prioritized by healthcare authorities under Saudi Vision 2030.