Which condition is characterized by the body's inability to fight infections due to low immune function?

The condition characterized by the body's inability to fight infections due to low immune function is immunodeficiency. This term specifically refers to situations where the immune system is not functioning optimally, leading to an increased susceptibility to infections. Immunodeficiency can be congenital (present at birth) or acquired (developing later in life due to factors such as viral infections like HIV, malnutrition, or certain medications that suppress the immune response).

In contrast, autoimmunity involves the immune system mistakenly attacking the body’s own tissues, which does not directly relate to an inability to fight infections but rather a misdirected immune response. Genetic disorders may influence immune function, but not all genetic disorders naturally lead to immunodeficiency. Cancer can impact immune function, particularly when therapies like chemotherapy or radiation are involved, but not all cancers result in a consistent state of low immune function. Therefore, immunodeficiency specifically and directly addresses the issue of low immune function leading to increased vulnerability to infections.