Final answer:
Primary T-Cell or CMI deficiencies are inherited immune disorders causing increased susceptibility to infections. Examples include severe combined immunodeficiency disease (SCID), which has severe impacts on both B-cell and T-cell mediated responses, often presenting dramatically in early life. These conditions are distinct from secondary immunodeficiencies, which are acquired and can also lead to vulnerability to infections.
Step-by-step explanation:
Understanding Primary T-Cell and CMI Deficiencies
Primary T-Cell or Cell-Mediated Immunity (CMI) deficiencies are a group of inherited disorders that impair the immune system's ability to fight off infections. Primary immunodeficiencies are predominantly caused by genetic abnormalities. Some examples include chronic granulomatous disease, X-linked agammaglobulinemia, selective IgA deficiency, and severe combined immunodeficiency disease (SCID). Each of these conditions results in an increased susceptibility to infection, often presenting in infancy or early childhood.
SCID is one of the more severe forms of Primary T-Cell/CMI deficiencies, affecting both B-cell and T-cell arms of the adaptive immune response. The presentation of patients with SCID is often dramatic; they may develop severe, life-threatening, opportunistic infections early in life. Vaccinations typically offer no protection due to the inability to develop immunological memory, and live vaccines can be harmful.
Secondary immunodeficiencies, on the other hand, are acquired and can be due to many factors including disease, diet, and environmental exposures. However, they can also impair B and T cells, leading to susceptibility to infections.
Immunodeficiencies, whether primary or secondary, have clinically significant impacts and require careful medical management to mitigate risks of infections and other related complications.