10
Diagnosis
Section 4. Immunologic Diagnosis of Predominantly
Antibody Deficiencies
Recommendation 4.1
➤ We recommend that patients with suspected antibody deficiencies
be evaluated with immunoglobulin measurement, antigen-specific
antibody responses, and lymphocyte phenotyping and exclusion of
secondary causes. (S-H)
Recommendation 4.2
➤ We recommend the diagnosis of agammaglobulinemia for patients
with low or undetectable serum immunoglobulin concentrations and
low or undetectable circulating B lymphocytes and normal total CD3+
T cell numbers. (S-H)
Recommendation 4.3
➤ We recommend the diagnosis of CVID for patients with low serum IgG
and low serum IgA and/or low IgM levels and demonstrated impaired
antibody response to infection or immunization and other causes of
hypogammaglobulinemia have been excluded. (S-H)
Table 3A. Detection Capabilities of Genetic Testing Platforms
for Various Genomic Findings
Genetic
defect
Sanger
sequencing
IEI targeted
gene panel
sequencing
Exome
sequencing
Whole
genome
sequencing
Chromosomal
microarray
analysis
Coding
single
nucleotide
variant
(SNV)
Yes
a
Yes Yes Yes No
Noncoding
SNV
Yes
a
Yes
b
Yes
b
Yes No
CNV No
Yes
b
Yes
b
Yes
Yes
b
Mosaicism Yes Yes
Yes
b
Yes
b
No
High
genomic
homolog y
Yes No No Yes No
Non-IEI
gene defects
No No Yes Yes Yes
a
If SNV is known.
b
Sensitivity varies with test protocol design.
