Review Of Related Disease (RRD) 4 Practice Exam

The main idea is that immunodeficiency is classified by which part of the immune system is defective: humoral (B-cell) immunity, cell-mediated (T-cell) immunity, or both (combined B- and T-cell deficiency). Congenital means the deficiency is present at birth, usually due to inherited genetic mutations. Acquired means it develops after birth, often as a result of infections (like HIV), treatments (chemotherapy or immunosuppressants), malnutrition, or other illnesses. Clinically, humoral defects tend to cause recurrent bacterial infections, especially with encapsulated organisms; T-cell defects lead to viral, fungal, and intracellular infections; combined defects affect multiple arms and are typically more severe. Other terms like autoimmune, autoinflammatory, or allergy describe different kinds of immune dysregulation and don’t fit the mechanism-by-immune-component framework.