Selective immunoglobulin A deficiency

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Classification according to ICD-10
D80.2 Selective immunoglobulin A deficiency
ICD-10 online (WHO version 2019)

The selective immunoglobulin A deficiency (engl. Selective IgA deficiency; SIGAD ) is occurring in humans most often congenital immunodeficiency . It is characterized by the absence of a certain class of antibodies , the immunoglobulin A . Affected patients may be symptom-free or suffer from a mostly relatively mild accumulation of respiratory infections . A causal treatment is not available. A prominent patient was the artist Niki de Saint Phalle .

causes

The exact cause of the selective IgA deficiency is only known for a rare subtype. Most cases remain unsolved in this regard. They occur sporadically; familial accumulation is only observed relatively rarely (around 20% of cases). The inheritance can then be autosomal dominant or autosomal recessive. The disease is associated with certain types of the major histocompatibility complex on the short arm of chromosome 6 (IGAD1 locus).

Frequency and occurrence (epidemiology)

The frequency of selective IgA deficiency is given in the literature as 1: 160 to 1: 18,500. Recent work suggests that the frequency in western industrialized countries is around 1: 600. This means that the prevalence is just over 1 ‰ (more than every thousandth person is affected). In regions with a different genetic background, the frequency is sometimes much lower (e.g. in Japan with 1: 18,500).

Clinic and Symptoms

The clinical manifestation of the disease is very variable. More than half of the patients are completely symptom-free (because IgM occurring in the mucous membranes takes over the functions of the missing IgA), around 30% suffer from recurrent (recurring) infections , especially of the respiratory tract. Less common complaints concern the digestive system, autoimmune diseases , allergies and tumor diseases . The following associations should be mentioned in detail:

diagnosis

The diagnosis is made by repeatedly determining the concentration of immunoglobulin A (IgA) in the blood serum . In patients with selective IgA deficiency, IgA is usually not detectable or is greatly reduced (close to the lower detection limit, always <0.3 g / l). Usually both subclasses (IgA 1 and IgA 2 ) are affected. IgG and IgM are normal. Other immunodeficiencies (see differential diagnosis) and secondary IgA deficiency due to medication or other diseases must be ruled out.

Selective IgA deficiency must be differentiated from the differential diagnosis

therapy

There is no treatment that addresses the cause of the disease. Patients who are symptom-free also do not need therapy, which is the majority of all patients. If infections occur, these must be treated according to the location of the infection and the pathogen, e.g. B. with antibiotics . Prophylactic antibiotic therapy is also required in some patients. Treatment with intravenous infusion of immunoglobulins (IVIG for iv immunoglobulin) comes i. d. Usually not considered, since in patients with selective IgA deficiency antibodies against IgA are formed, which can then lead to severe allergic reactions (IgA is "unknown" to the body until then, which is why a defense reaction is initiated). The selective IgA deficiency is thus the most important contraindication for IVIG therapy. This mechanism can also lead to allergic reactions during blood transfusions if the recipient suffers from selective IgA deficiency. This is also the reason why patients with selective IgA deficiency are recommended to carry an emergency ID card with them and to make treating doctors aware of the diagnosis.

forecast

The life expectancy of patients with selective IgA deficiency is usually normal or only slightly reduced. The prognosis is therefore considerably better than for any other congenital immunodeficiency.

literature

  • Mark Ballow: Primary immunodeficiency disorders: Antibody deficiency . In: J Allergy Clin Immunol . Vol. 109, No. 4, 2002, pp. 581-591, ISSN  0091-6749 .
  • Lennart Hammarström, Igor Vorechovský and David B. Webster: Selective IgA Deficiency (SIgAD) and common variable immunodeficiency (CVID) . In: Clin Exp Immunol . Vol. 120, 2000, pp. 225-231, ISSN  0009-9104 .
  • Hans-Hartmut Peter, Werner J. Pichler (Ed.): Clinical Immunology . 2nd Edition. Urban and Schwarzenberg, Munich; Vienna; Baltimore 1996, ISBN 3-541-14892-6 .
  • Fred S. Rosen et al .: Primary Immunodeficiency Diseases. Report of an IUIS Scientific Committee . In: Clin Exp Immunol . Vol. 118 (Suppl. 1), 1999, pp. 1-28, ISSN  0009-9104 .

Web links

swell

  1. ↑ Source: Hannoversche Allgemeine Zeitung , January 27, 2012, No. 23, page 6. Diagnosis by the rheumatologist Henning Zeidler , professor emeritus at the Hannover Medical School .
  2. ↑ a b Lennart Hammarström et al .: Selective IgA Deficiency (SIgAD) and common variable immunodeficiency (CVID) . In: Clin Exp Immunol . Vol. 120, 2000, pp. 225-231, ISSN  0009-9104
  3. ↑ a b c d e f g h i Mark Ballow: Primary immunodeficiency disorders: Antibody deficiency . In: J Allergy Clin Immunol . Vol. 109, No. 4, 2002, pp. 581-591, ISSN  0091-6749
  4. ↑ Igor Vorechovský et al .: Fine mapping of IGAD1 in IgA deficiency and common variable immunodeficiency: Identification and Characterization of haplotypes shared by Affected Members of 101 multiple-Case Families . In: J Immunol . Vol. 164, No. 8, 2000, pp. 4408-4416, ISSN  0022-1767
  5. ↑ Luis F. Pereira et al .: Prevalence of Selective IgA Deficiency in Spain: More Than We Thought . In: Blood . Vol. 90, No. 2, 1997, p. 893, ISSN  0006-4971
  6. ↑ a b T. Kanoh et al .: Selective IgA deficiency in Japanese blood donors: frequency and statistical analysis . In: Vox Sanguinis . Vol. 50, No. 2, 1986, pp. 81-86, ISSN  0042-9007
  7. ↑ a b Lene Mellemkjær et al .: Cancer risk among patients with IgA deficiency or common variable immunodeficiency and their relatives: a combined Danish and Swedish study . In: Clin Exp Immunol . Vol. 130, 2002, pp. 495-500, ISSN  0009-9104