Which of the following clinical manifestations is a common symptom of primary immunodeficiency disorders?

Explanation: The correct answer is b. Recurrent skin infections. Recurrent skin infections are common clinical manifestations of immunodeficiency disorders in the elderly. The weakened immune system makes the skin more susceptible to infections and delays wound healing.

Incorrect choices:

a. Impaired balance and coordination are more commonly associated with neurological disorders or conditions affecting the musculoskeletal system, not immunodeficiency disorders.

c. Vision changes and blindness may be seen in conditions affecting the eyes or the visual system but are not typical clinical manifestations of immunodeficiency disorders.

d. Hearing loss is more commonly associated with conditions affecting the ears or the auditory system and is not a typical clinical manifestation of immunodeficiency disorders.

Explanation: The correct answer is d. Flow cytometry for lymphocyte subsets. Flow cytometry is a diagnostic test used to analyze the quantity and types of lymphocytes in the blood, which helps identify abnormalities in the immune system and diagnose immunodeficiency disorders.

Incorrect choices:

a. A complete blood count (CBC) provides general information about the client's overall blood cell counts, but it does not specifically diagnose immunodeficiency disorders.

b. Urinalysis is used to assess kidney function and identify urinary tract infections but is not a specific test for diagnosing immunodeficiency disorders.

c. Skin testing for allergies is performed to identify allergic reactions to specific allergens and is not used to diagnose immunodeficiency disorders.