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Disease Profile

Specific antibody deficiency

Prevalence
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

Unknown

Age of onset

Childhood

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ICD-10

D80.8

Inheritance

Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease

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Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype

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X-linked
dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.

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X-linked
recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder

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Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

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Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.

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Not applicable

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Other names (AKA)

Immunodeficiency due to selective anti-polysaccharide antibody deficiency; Impaired polysaccharide responsiveness; Selective antibody deficiency with normal immunoglobulins;

Categories

Congenital and Genetic Diseases; Immune System Diseases

Summary

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
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Orpha Number: 70593

Definition
Immunodeficiency due to selective anti-polysaccharide antibody deficiency is characterized by normal immunoglobulin levels (including IgG sub-classes) but impaired polysaccharide responsiveness (IPR).

Epidemiology
Although the prevalence is not really known, around 100 cases have been reported in the literature, indicating that this syndrome is a rare primary immunodeficiency. Approximately 60% of patients are male.

Clinical description
The onset of the disease generally occurs during childhood, between 2 to 7 years of age. Patients suffer from recurrent bacterial infections, mostly of the respiratory tract. The offending bacteria are those with a polysaccharide capsule, such as pneumococci, Hemophilus influenzae, meningococci and group B streptococci. Sepsis and meningitis occur less frequently. Allergic manifestations are observed in half of the patients.

Etiology
This immunodeficiency is likely heterogeneous with multiple causes. Genetic factors may play a role, as indicated by the observation of a higher prevalence in certain ethnic populations and of some familial cases. Several hypotheses have been proposed concerning the cause of the disease, but the most likely is a defect in splenic marginal zone B cells. Indeed, polysaccharide antigens are concentrated and presented to B cells by the dendritic cells within the spleen marginal zone. In favour of this hypothesis is the observation of an impaired polysaccharide antibody response in splenectomized patients.

Diagnostic methods
The diagnosis is established by identifying deficient antibody response to polysaccharide antigens (usually Haemophilus influenzae b vaccine) contrasting with normal immunoglobulin (including the IgG subclasses) levels and unaffected antibody production to protein antigens (tetanus toxoid, diphtheria). As most children under 2 years of age have a physiological defect in response to polysaccharide antigens, the diagnosis cannot be assessed before this age.

Differential diagnosis
The differential diagnosis should exclude other primary immunodeficiencies also characterized by a defective response to polysaccharide antigens, essentially the IgG2-IgG4 deficiency. A defect in antibody production to polysaccharides may be associated with the Wiskott-Aldrich syndrome or Common Variable Immuno Deficiency (CVID). Recently, an adult patient with Btk-deficiency has been reported as only affected by impaired polysaccharide responsiveness.

Management and treatment
Besides their use for controlling infections, antibiotics should also be given as a prophylactic treatment. Immunoglobulin substitution could also be of benefit whenever prophylactic antibiotherapy fails. Vaccination with the conjugate antipneumococcal vaccine is also required.

Prognosis
Under treatment, infections are generally well controlled. However, patients should be carefully followed-up since this condition can evolve into a more severe immunodeficiency (IgG subclass deficiency or CVID).

Visit the Orphanet disease page for more resources.

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.