Question

Case Studies Immunodeficiency

History and Physical Examination

J.J. is a 5-year-old boy who has suffered from repeated upper respiratory infections since he was 16 months old. At 4 years of age, he was diagnosed with allergic asthma. The following winter, at age 5, he was admitted to the hospital twice for acute asthma with a secondary bacterial pulmonary infection.

At the second admission, a complete blood count (CBC), sputum culture, and immune status workup were ordered.

Laboratory Data

Assay Patient Results Reference Range

Hemoglobin 13.5

Hematocrit 40%

Total WBC count 16.2 × 109/L  

Absolute lymphocyte count 4.3 × 109/L 2.7-5.4

T lymphocytes 2.4 × 109/L 2.7-5.3

B lymphocytes 1.0 × 109/L 0.6-1.4

Antibodies to normal childhood immunization: present

Serum immunoglobulin profile

IgM, IgG, and IgA bands: normal

IgE and IgD: no bands observed

Serum total protein

IgM 2.4 g/L 0.5-2.0

IgG 18.9 g/L 4.9-16.1

IgA 0.020 g/L 0.4-2.0

Questions

1. What abnormal laboratory data does the patient demonstrate?

a. Decreased T lymphocyte count

b. Decreased IgA level

c. Decreased total protein

d. Both a and b

2. What is the etiology of this patient’s recurring infections?

a. Neutropenia

b. Lymphocytosis

c. Impaired phagocytosis

d. IgA deficiency

3. What clinical conditions are associated with this patient’s immune problem?

a. Recurrent infections

b. Allergies

c. Increased incidence of inflammatory conditions

d. All the above

Answer 1

1. Decreased T lymphocyte - 2.4 × 10⁹/L and IgA level - 0.020 g/L. Option d is the correct answer.

2. IgA deficiency causes recurrent upper respiratory infections in children. Option d is the correct answer.

3. Recurrent infections are associated with this patient's immune problem. Option a is the correct answer.