Victoria and Rusty were worried about their infant Bailey since his first trip to the hospital at 3 weeks of age. That time he had a temperature of 103'F and a runny nose. The emergency physician checked Bailey over but sent him home saying it was only a com- mon cold, probably brought home by his older sib- lings, and that all would be fine. But Bailey's health has not been fine as he has been having an unusual number of bacterial infections and he is not yet quite 1 year old. The antibiotics that Bailey's physician prescribed have cleared up his bacterial respiratory infections but another infection always follows. Now that Bailey is back at the hospital with pneumonia, his physician has ordered a number of other laboratory tests as he is now worried about Bailey's immune system. The studies showed that Bailey had normal levels of B cells and T cells, with his immu- noglobulin levels and hematology results listed in CASE STUDY TABLE 11-1.1. CASE STUDY TABLE 11-1.1 LABORATORY RESULTS BAILEY'S TEST VALUE REFERENCE RANGE 6 mo-2 y: 30.9-37.0% 6 mo-2 y: 10.3-12.4 g/dL 14.0 x 10/uL 6 mo-2 y: 6.2-14.5 x 10/uL Hct 35% Hgb 11.9 g/dL WBC IgG 153 mg/dL 1-3 y: 507-1,407 mg/dL 576 mg/dL 11 mg/dL O mg/dL IgM 1-3 y: 18-171 mg/dL IgA 1-3 y: 63-298 mg/dL IgD Newborn to adult: 0-8 mg/dL IgE 1 kIU/L 1-3 y: <90 klU/L 8.7 g/dl Total protein Albumin 3.8 g/dL 1 y: 5.4-7.5 g/dL 1-3 y: 3.4-4.2 g/dL Questions: 1. Why do Bailey's recurring bacterial infections cor- relate with these laboratory results? 2. What is immunoglobulin isotype switching? How does isotype switching explain the lack of IgG, IgA, and IgE in Bailey's blood? 3. List the immunoglobulin type and the age it appears in the blood of a baby from birth to 18 months. 4. What treatment can be given to Bailey? Immediately? In the future?
Victoria and Rusty were worried about their infant Bailey since his first trip to the hospital at 3 weeks of age. That time he had a temperature of 103'F and a runny nose. The emergency physician checked Bailey over but sent him home saying it was only a com- mon cold, probably brought home by his older sib- lings, and that all would be fine. But Bailey's health has not been fine as he has been having an unusual number of bacterial infections and he is not yet quite 1 year old. The antibiotics that Bailey's physician prescribed have cleared up his bacterial respiratory infections but another infection always follows. Now that Bailey is back at the hospital with pneumonia, his physician has ordered a number of other laboratory tests as he is now worried about Bailey's immune system. The studies showed that Bailey had normal levels of B cells and T cells, with his immu- noglobulin levels and hematology results listed in CASE STUDY TABLE 11-1.1.
CASE STUDY TABLE 11-1.1 LABORATORY RESULTS BAILEY'S TEST VALUE REFERENCE RANGE 6 mo-2 y: 30.9-37.0% 6 mo-2 y: 10.3-12.4 g/dL 14.0 x 10/uL 6 mo-2 y: 6.2-14.5 x 10/uL Hct 35% Hgb 11.9 g/dL WBC IgG 153 mg/dL 1-3 y: 507-1,407 mg/dL 576 mg/dL 11 mg/dL O mg/dL IgM 1-3 y: 18-171 mg/dL IgA 1-3 y: 63-298 mg/dL IgD Newborn to adult: 0-8 mg/dL IgE 1 kIU/L 1-3 y: <90 klU/L 8.7 g/dl Total protein Albumin 3.8 g/dL 1 y: 5.4-7.5 g/dL 1-3 y: 3.4-4.2 g/dL
Questions:
1. Why do Bailey's recurring bacterial infections cor- relate with these laboratory results?
2. What is immunoglobulin isotype switching? How does isotype switching explain the lack of IgG, IgA, and IgE in Bailey's blood?
3. List the immunoglobulin type and the age it appears in the blood of a baby from birth to 18 months.
4. What treatment can be given to Bailey? Immediately? In the future?
Step by step
Solved in 2 steps
