Autoimmune polyglandular syndrome (APS Type I) is an inherited immune system problem that causes autoimmunity. The immune system in children with the disorder has trouble distinguishing between the normal tissues in the body and invading microorganisms, and so the immune system attacks the body’s own tissues. In particular, people with APS Type I have endocrine (gland) problems, with low adrenal gland function, low parathyroid function causing low calcium levels, and problems with yeast (Candida) infections in the skin and nails. There are two other types, APS Type II and APS Type III, that are similar, but have slightly different endocrine problems.
APS affects males and females equally. It is inherited as an autosomal recessive disorder. This means that there are not typically affected parents or grandparents, but there may be affected siblings. The changes in the APS gene that cause the symptoms can be found in people throughout the world, but it is somewhat more frequent in Finnish, Jewish, and Persian populations.
Signs and Symptoms
Children with APS Type I typically begin having problems in early childhood. Often diarrhea and malnutrition from poor absorption of nutrients is the first sign. Shortly thereafter children may have mucocutaneous candidiasis, or yeast infections of the skin, nails and mouth. Yeast infection of the mouth is known as thrush. These infections usually require antifungal medications to resolve.
In later childhood, children may begin to have low calcium levels, which can lead to seizures if not treated. The low calcium is due to the autoimmune reaction against the parathyroid glands, which are responsible for regulating the body’s calcium levels. Subsequently, children may also develop low adrenal gland function. Adrenals are glands that regulate salt levels in the body and if these fail, low blood pressure and shock may develop. Children may also have darkening skin when adrenal function is poor.
Children with APS Type I also may develop other autoimmune problems. These include autoimmune inflammation of the liver (chronic active hepatitis), anemia (a type known as pernicious anemia from failure to absorb vitamin B12), hair loss, and vitiligo (patches of skin where the skin pigment has been lost). There may also be inflammation in the ovaries or testis, which can lead to infertility.
Finally, children with APS Type I may have problems in the development of tooth enamel, corneas, and hair, leading to abnormal appearing teeth and vision problems.
APS Type II is similar to Type I, but they do not have parathyroid problems and do not have candidal skin infections. They do have low thyroid function and juvenile (autoimmune) diabetes. In contrast, patients with APS Type I only rarely have low thyroid or diabetes. Patients with APS Type III do not have adrenal problems but do have autoimmune thyroid problems and at least one other endocrine problem.
The gene for APS Type I was identified in 1997, and is known as the autoimmune regulator gene (AIRE). The immune system develops by teaching certain immune cells, called T cells, what things to ignore and what things to attack. The AIRE gene is involved in helping the T cells learn what other tissues in the body look like. If the AIRE gene is missing, T cells cannot learn to recognize gland tissue as being part of the body, and so they try to reject it.
To be considered to have APS Type I, a patient needs to have at least two of the follow three problems: autoimmune adrenal disease, autoimmune parathyroid disease or candidal infections of the skin or nails. Blood tests are done that measure hormone levels and the levels of autoantibodies, signs of immune reactions against the body tissues. This helps determine exactly which problems a person with APS Type I has. When APS Type I is strongly suspected, the AIRE gene can be sequenced to determine if there are changes in it that would confirm the diagnosis.
There is currently no treatment to change the underlying problem, the change in the AIRE gene that causes autoimmunity. There are many things that can be done to control the progress of the disease though. For candidal infections, patients can be given antifungal antibiotics, and most take these on a life-long basis to suppress these infections. For low calcium, calcium and vitamin D supplements can be taken. For adrenal problems, corticosteroids can be taken, which replace the function of the adrenal gland. For the autoimmunity, immune suppressive medications may be needed. These help to reduce the immune response from progressing against the affected organs and keep them healthy and functioning longer. Care from an ophthalmologist and dentist may be needed to address the teeth and corneal problems.
APS does not resolve and new endocrine problems can continue to appear over the entire lifetime of the individual. Depending on the severity of the autoimmune problems though, survival may be for a normal lifespan.
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There are many websites and articles discussing the science behind but few links that are relevant or appropriate for parents.
Eisenbarth GS and Gottlieb PA. Autoimmune Polyendocrine Syndromes. N Engl J Med 2004;350:2068-79.
OMIM. Available at http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=240300. Accessed 9/11/06.
Notarangelo LD, et al. AIRE and immunological tolerance: insights from the study of autoimmune polyendocrinopathy candidiasis and ectodermal dystrophy. Curr Opin Allergy Clin Immunol 2004;4:491-496.
Su MA and Anderson MS. Aire: an update. Curr Opin Immunol. 2004;16:746-752