Humoral immune deficiency explained

Humoral immune deficiencies are conditions which cause impairment of humoral immunity, which can lead to immunodeficiency. It can be mediated by insufficient number or function of B cells, the plasma cells they differentiate into, or the antibody secreted by the plasma cells.^[1] The most common such immunodeficiency is inherited selective IgA deficiency, occurring between 1 in 100 and 1 in 1000 persons, depending on population. They are associated with increased vulnerability to infection, but can be difficult to detect (or asymptomatic) in the absence of infection.

Signs and symptoms

Signs/symptoms of humoral immune deficiency depend on the cause, but generally include signs of infection such as:^[2]

• Sinusitis
• Sepsis
• Skin infection
• Pneumonia

Causes

Cause of this deficiency is divided into primary and secondary:

• Primary the International Union of Immunological Societies classifies primary immune deficiencies of the humoral system as follows:^{[3] [4]}

• Absent B cells with a resultant severe reduction of all types of antibody: X-linked agammaglobulinemia (btk deficiency, or Bruton's agammaglobulinemia), μ-Heavy chain deficiency, l 5 deficiency, Igα deficiency, BLNK deficiency, thymoma with immunodeficiency

• B cells low but present, but with reduction in 2 or more isotypes (usually IgG & IgA, sometimes IgM): common variable immunodeficiency (CVID), ICOS deficiency, CD19 deficiency, TACI (TNFRSF13B) deficiency, BAFF receptor deficiency.

• Normal numbers of B cells with decreased IgG and IgA and increased IgM: Hyper-IgM syndromes

• Normal numbers of B cells with isotype or light chain deficiencies: heavy chain deletions, kappa chain deficiency, isolated IgG subclass deficiency, IgA with IgG subsclass deficiency, selective immunoglobulin A deficiency

• Transient hypogammaglobulinemia of infancy (THI)
• Secondary secondary (or acquired) forms of humoral immune deficiency are mainly due to hematopoietic malignancies and infections that disrupt the immune system:^[5]

• Multiple myeloma

• Chronic lymphoid leukemia

• AIDS

Diagnosis

In terms of diagnosis of humoral immune deficiency depends upon the following:^{[6] [7]}

• Measure serum immunoglobulin levels
• B cell count
• Family medical history

Treatment

Treatment for B cell deficiency (humoral immune deficiency) depends on the cause, however generally the following applies:^[6]

• Treatment of infection (antibiotics)
• Surveillance for malignancies
• Immunoglobulin replacement therapy

See also

• Immunodeficiency
• T cell deficiency

Further reading

• Ahn . Sam . Cunningham-Rundles . Charlotte . Charlotte Cunningham-Rundles . 2017-05-11 . Role of B cells in common variable immune deficiency . Expert Review of Clinical Immunology . 5 . 5 . 557–564 . 10.1586/eci.09.43 . 1744-666X . 2922984 . 20477641.
• Book: Honjo, Tasuku . Molecular Biology of B Cells . Reth . Michael . Radbruch . Andreas . Alt . Frederick . 2014-10-09 . Elsevier . 9780123984906 . en.

External links

• PubMed

Notes and References

1. Pieper . Kathrin . Grimbacher . Bodo . Eibel . Hermann . 2013-04-01 . B-cell biology and development . Journal of Allergy and Clinical Immunology . en . 131 . 4 . 959–971 . 10.1016/j.jaci.2013.01.046 . 0091-6749 . 23465663 . free.
2. Book: N. Franklin Adkinson Jr. . Middleton's Allergy: Principles and Practice . Bochner . Bruce S. . Burks . Wesley . Busse . William W. . Holgate . Stephen T. . 2013-11-01 . Elsevier Health Sciences . 9780323085939 . 1134 . en.
3. Notarangelo L, Casanova JL, Conley ME, etal . 2006 . Primary immunodeficiency diseases: an update from the International Union of Immunological Societies Primary Immunodeficiency Diseases Classification Committee Meeting in Budapest, 2005 . J. Allergy Clin. Immunol. . 117 . 4 . 883–96 . 10.1016/j.jaci.2005.12.1347 . 16680902 . free.
4. 2017-01-06 . Pure B-Cell Disorders: Background, Pathophysiology, Epidemiology .
5. https://books.google.com/books?id=iPuvQDcqW88C&pg=PA432 Page 432
6. Fried . Ari J. . Bonilla . Francisco A. . 2009-07-01 . Pathogenesis, Diagnosis, and Management of Primary Antibody Deficiencies and Infections . Clinical Microbiology Reviews . en . 22 . 3 . 396–414 . 10.1128/CMR.00001-09 . 0893-8512 . 2708392 . 19597006.
7. Book: Cecil, Russell La Fayette . Goldman's Cecil Medicine, Expert Consult Premium Edition -- Enhanced Online Features and Print, Single Volume,24: Goldman's Cecil Medicine . Goldman . Lee . Schafer . Andrew I. . 2012-01-01 . Elsevier Health Sciences . 978-1437716047 . 1618 . en.