Primary Immunodeficiency Diseases (PIDD) Quiz

False: Selective IgA deficiency, a type of primary immunodeficiency disease, is more common than cystic fibrosis and sickle cell disease in African-American individuals, two conditions that many more people recognize. The true incidence and prevalence of most primary immunodeficiency diseases are not known because very often the diagnosis is not considered.

D: One of the primary roles of the immune system is to defend the body against pathogens that cause infections. Immune deficiencies lead to weaknesses in that defense.

B: Recurrent ear and sinus infections are two warning signs of primary immunodeficiency. The other types of infections are not classic hallmarks of primary immunodeficiency diseases.

B: T lymphocytes are critical for protection, especially against a number of fungal and viral pathogens. These immune cells develop within the thymus gland, and absence of a thymus on a chest x-ray in a young infant can be a sign of missing T lymphocytes. Congenital absence of T lymphocytes is a medical emergency and must be treated immediately.

C: Neutrophils engulf and digest bacteria and other types of organisms. They also play an important role in wound healing. Patients with chronic granulomatous disease, for example, develop recurrent abscesses of the skin if they are not adequately treated.

C: Very high serum IgE levels can be seen in patients with allergic diseases, such as asthma and eczema. Hyper-IgE syndrome is marked by susceptibility to infections, resulting in recurrent skin abscesses. Low platelet counts and elevated IgE levels can be found in another primary immunodeficiency disease, Wiskott-Aldrich syndrome.

False: Patients with neutrophil defects typically have normal or sometimes even elevated levels of immunoglobulins. It is important to also note that having normal overall quantities of immunoglobulins does not necessarily mean that a person has normal antibody function.

A: B lymphocytes make antibodies, which are especially important for defending against infections at mucosal surfaces, such as the ones along the respiratory and gastrointestinal tracts. Patients who cannot make antibodies have a primary immunodeficiency disease. While newborn screening tests have been developed and approved to look for T lymphocyte deficiency, no newborn screening tests are available at this time to evaluate for B lymphocyte defects.

C: Skin tests to Candida and mumps can be used much in the same way as testing for tuberculosis is performed to assess for the presence of normal T lymphocyte function. The other tests do not evaluate T lymphocyte function. Elevated sweat chloride levels are found in cystic fibrosis, the respiratory burst assay is a test of neutrophil function, and ciliary biopsy is performed to assess for primary ciliary dyskinesia.

False: Patients with neutrophil defects do not require immunoglobulin replacement therapy unless they have defective antibody function. Some patients with antibody deficiencies can be managed simply with long-term courses of antibiotics.

False: A patient who is properly managed and treated should not require isolation from public activities.

False: Many primary immunodeficiency diseases can now be cured by stem cell transplantation. New therapies, such as gene therapy and thymus transplantation, are actively being developed as techniques to permanently treat other specific primary immunodeficiency diseases.