Humoral immune deficiencies are conditions which cause impairment of

humoral immunity Humoral immunity is the aspect of immunity that is mediated by macromolecules - including secreted antibodies, complement proteins, and certain antimicrobial peptides - located in extracellular fluids. Humoral immunity is named so because it ...

, which can lead to

immunodeficiency Immunodeficiency, also known as immunocompromisation, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that a ...

. It can be mediated by insufficient number or function of

B cell B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or ...

s, the

plasma cell Plasma cells, also called plasma B cells or effector B cells, are white blood cells that originate in the lymphoid organs as B lymphocytes and secrete large quantities of proteins called antibodies in response to being presented specific sub ...

s they differentiate into, or the

antibody An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and Viral disease, viruses. The antibody recognizes a unique m ...

secreted by the plasma cells. The most common such immunodeficiency is inherited

selective IgA deficiency Selective immunoglobulin A (IgA) deficiency (SIgAD) is a genetic immunodeficiency, a type of hypogammaglobulinemia. People with this deficiency lack immunoglobulin A (IgA), a type of antibody that protects against infections of the mucous membran ...

, 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: *

Sinusitis Sinusitis, also known as rhinosinusitis, is inflammation of the mucous membranes that line the sinuses resulting in symptoms that may include thick nasal mucus, a plugged nose, and facial pain. Other signs and symptoms may include fever, he ...

Sepsis Sepsis, formerly known as septicemia (septicaemia in British English) or blood poisoning, is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage is foll ...

* Skin infection *

Pneumonia Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severi ...

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: 170 px, Hyper-IgM syndromes(immunoglobulin M) :* Absent B cells with a resultant severe reduction of all types of antibody:

X-linked agammaglobulinemia X-linked agammaglobulinemia (XLA) is a rare genetic disorder discovered in 1952 that affects the body's ability to fight infection. As the form of agammaglobulinemia that is X-linked, it is much more common in males. In people with XLA, the whit ...

( btk deficiency, or Bruton's agammaglobulinemia), μ- Heavy chain deficiency, l 5 deficiency, Igα deficiency,

BLNK The B-cell linker protein is encoded by the ''BLNK'' gene and is an adaptor protein also known as SLP-65, BASH, and BCA. BLNK is expressed in B cells and macrophages and plays a large role in B cell receptor signalling, in a fashion analogous to ...

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 Common variable immunodeficiency (CVID) is an immune disorder characterized by recurrent infections and low antibody levels, specifically in immunoglobulin (Ig) types IgG, IgM and IgA. Symptoms generally include high susceptibility to foreign ...

(CVID), ICOS deficiency,

CD19 B-lymphocyte antigen CD19, also known as CD19 molecule ( Cluster of Differentiation 19), B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12 and CVID3 is a transmembrane protein that in humans is encoded by the gene ''CD19''. In humans, ...

deficiency,

TACI Transmembrane activator and CAML interactor (TACI), also known as tumor necrosis factor receptor superfamily member 13B (TNFRSF13B) is a protein that in humans is encoded by the TNFRSF13B gene. TNFRSF13B is a transmembrane protein of the TNF re ...

(TNFRSF13B) deficiency,

BAFF receptor BAFF receptor (B-cell activating factor receptor, BAFF-R), also known as tumor necrosis factor receptor superfamily member 13C (TNFRSF13C) and BLyS receptor 3 (BR3), is a membrane protein of the TNF receptor superfamily which recognizes BAFF, an ...

deficiency. :* Normal numbers of B cells with decreased IgG and

IgA Iga may refer to: Arts and entertainment * Ambush at Iga Pass, a 1958 Japanese film * Iga no Kagemaru, Japanese manga series * Iga, a set of characters from the Japanese novel '' The Kouga Ninja Scrolls'' Biology * ''Iga'' (beetle), a gen ...

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:Page 432
Chapter 22, Table 22.1 in: :*

Multiple myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibodies. Often, no symptoms are noticed initially. As it progresses, bone pain, ane ...

Chronic lymphoid leukemia Chronic lymphocytic leukemia (CLL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). Early on, there are typically no symptoms. Later, non-painful lymph node swelling, feeling tired, fever, nigh ...

:* AIDS

Diagnosis

In terms of diagnosis of ''humoral immune deficiency'' depends upon the following: * Measure ''serum immunoglobulin levels'' *

count * Family

medical history The medical history, case history, or anamnesis (from Greek: ἀνά, ''aná'', "open", and μνήσις, ''mnesis'', "memory") of a patient is information gained by a physician by asking specific questions, either to the patient or to other pe ...

Treatment

Treatment for ''B cell deficiency'' (humoral immune deficiency) depends on the cause, however generally the following applies: * Treatment of

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable d ...

(antibiotics) * Surveillance for malignancies *

Immunoglobulin An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...

replacement therapy

References

External links

PubMed
{{Medicine Predominantly antibody deficiencies