Polyglandular Deficiency Syndromes

The etiology is most often autoimmune. Risk factors for development of autoimmunity include

Genetic factors include the AIRE gene mutation, which is causative of type 1, and certain human leukocyte antigen (HLA) subtypes, which are important in the development of types 2 and 3.

Environmental triggers include viral infections, dietary factors, and other as yet unknown exposures.

Immune check point inhibitors Immunotherapy and Targeting Inhibitors of Immune Responses A number of immunologic interventions, both passive and active, can be directed against tumor cells. (See also Immunotherapeutics.) In passive cellular immunotherapy, specific effector cells... read more , which are used to treat some types of cancer and are associated with autoimmune endocrine disease, including hypophysitis, thyroid disease, primary adrenal insufficiency, and type 1 diabetes mellitus, are a trigger.

The underlying autoimmune reaction involves autoantibodies against endocrine tissues, cell-mediated autoimmunity Cellular Components of the Immune System The immune system consists of cellular components and molecular components that work together to destroy antigens. (See also Overview of the Immune System.) Although some antigens (Ags) can... read more , or both and leads to inflammation, lymphocytic infiltration, and partial or complete gland destruction. More than one endocrine gland is involved, although clinical manifestations are not always simultaneous. The autoimmune reaction and associated immune system dysfunction can also damage nonendocrine tissues.

Three patterns of autoimmune failure have been described in polyglandular deficiency syndrome (see table Characteristics of Polyglandular Deficiency Syndromes Characteristics of Polyglandular Deficiency Syndromes ), which likely reflect different autoimmune abnormalities. Some experts combine type 2 and type 3 into a single group. The prevalence of type 2 is about 1 per 1000 whereas type 1 occurs in about 1 per 100,000 (1 Classification reference Polyglandular deficiency syndromes are characterized by sequential or concurrent deficiencies in the function of several endocrine glands that have a common cause. Etiology is most often autoimmune... read more ).

The clinical appearance of patients with polyglandular deficiency syndromes is the sum of the individual endocrine deficiencies and associated nonendocrine disorders; their symptoms and signs are discussed elsewhere in THE MANUAL. The deficiencies do not always appear at the same time and may require a period of years to manifest; in such cases they do not follow a particular sequence.

Diagnosis of polyglandular deficiency syndromes is suggested clinically and confirmed by detecting deficient hormone levels. Other causes of multiple endocrine deficiencies include hypothalamic-pituitary dysfunction and coincidental endocrine dysfunction due to separate causes (eg, tuberculous hypoadrenalism and nonautoimmune hypothyroidism in the same patient or sarcoidosis Sarcoidosis Sarcoidosis is an inflammatory disorder resulting in noncaseating granulomas in one or more organs and tissues; etiology is unknown. The lungs and lymphatic system are most often affected, but... read more involving multiple endocrine glands).

Type 1 polyglandular deficiency is associated with autoantibodies against type 1 interferons, and presence of these antibodies suggests the diagnosis, which can be confirmed by mutational analysis of the AIRE gene. Detecting autoantibodies to each affected glandular tissue can help differentiate polyglandular deficiency syndromes from the other causes, and elevated levels of pituitary tropic hormones (eg, thyroid-stimulating hormone) suggest the hypothalamic-pituitary axis is intact (although some patients with type 2 polyglandular deficiency syndrome have hypothalamic-pituitary insufficiency).

Because decades may pass before the appearance of all manifestations, lifelong follow-up is prudent; unrecognized hypoparathyroidism or adrenal insufficiency can be life threatening.

Relatives should be made aware of the diagnosis and screened when appropriate. A trial following relatives of patients with type 1 diabetes for development of autoimmunity found antibodies associated with type 1 diabetes, celiac disease, and/or thyroid disease in 21.5% of subjects (1 Diagnosis reference Polyglandular deficiency syndromes are characterized by sequential or concurrent deficiencies in the function of several endocrine glands that have a common cause. Etiology is most often autoimmune... read more ).

Treatment of the various individual glandular deficiencies is discussed elsewhere in THE MANUAL; the treatment of multiple deficiencies can be more complex than treatment of an isolated endocrine deficiency. For example, treatment of hypothyroidism with thyroid hormone replacement can precipitate an adrenal crisis in patients with undiagnosed adrenal insufficiency.

Chronic mucocutaneous candidiasis associated with type 1 polyglandular deficiency usually requires lifelong antifungal therapy Treatment (eg, oral fluconazole or ketoconazole).

Clinical trials of interventions to slow the autoimmune process in type 1 diabetes have shown some promise in delaying the complete destruction of insulin-producing beta-cells. Treatments that have been evaluated include immunotherapy, including using the anti-CD monoclonal antibody teplizumab, and umbilical cord blood transplantation. However, the impact of these measures in preventing other autoimmune endocrine deficiencies in patients with type 1 diabetes remains unknown (1, 2, 3, 4 Treatment references Polyglandular deficiency syndromes are characterized by sequential or concurrent deficiencies in the function of several endocrine glands that have a common cause. Etiology is most often autoimmune... read more ).