Primary immunodeficiency for the primary care provider

Primary immunodeficiencies are a group of heterogeneous disorders resulting from defects affecting the function of ≥1 parts of the immune system. Current estimates of the prevalence of primary immunodeficiency disease are one in 1200 patients. In Ontario, where the average general practitioner follows 1300 to 2000 patients, an estimated two patients will have primary immunodeficiency. With new primary immunodeficiencies being described at an exponential rate, and those previously described becoming better understood, it is challenging for health care providers to stay up to date. Knowledge gaps delay diagnosis and treatment, leading to increased morbidity and mortality. The present review aims to provide the primary care provider with the tools necessary to recognize primary immunodeficiency and assist in establishing diagnoses.