Autoimmune Addison disease

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Autoimmune Addison disease affects the function of the adrenal glands, which are small hormone-producing glands located on top of each kidney. It is classified as an autoimmune disorder because it results from a malfunctioning immune system that attacks the adrenal glands. As a result, the production of several hormones is disrupted, which affects many body systems.

The signs and symptoms of autoimmune Addison disease can begin at any time, although they most commonly begin between ages 30 and 50. Common features of this condition include extreme tiredness (fatigue), nausea, decreased appetite, and weight loss. In addition, many affected individuals have low blood pressure (hypotension), which can lead to dizziness when standing up quickly; muscle cramps; and a craving for salty foods. A characteristic feature of autoimmune Addison disease is abnormally dark areas of skin (hyperpigmentation), especially in regions that experience a lot of friction, such as the armpits, elbows, knuckles, and palm creases. The lips and the inside lining of the mouth can also be unusually dark. Because of an imbalance of hormones involved in development of sexual characteristics, women with this condition may lose their underarm and pubic hair.

Other signs and symptoms of autoimmune Addison disease include low levels of sugar (hypoglycemia) and sodium (hyponatremia) and high levels of potassium (hyperkalemia) in the blood. Affected individuals may also have a shortage of red blood cells (anemia) and an increase in the number of white blood cells (lymphocytosis), particularly those known as eosinophils (eosinophilia).

Autoimmune Addison disease can lead to a life-threatening adrenal crisis, characterized by vomiting, abdominal pain, back or leg cramps, and severe hypotension leading to shock. The adrenal crisis is often triggered by a stressor, such as surgery, trauma, or infection.

Individuals with autoimmune Addison disease or their family members can have another autoimmune disorder, most commonly autoimmune thyroid disease or type 1 diabetes.

Causes and biological mechanisms

From: MedlinePlus Genetics, National Library of Medicine

The cause of autoimmune Addison disease is complex and not completely understood. A combination of environmental and genetic factors plays a role in the disorder, and changes in multiple genes are thought to affect the risk of developing the condition.

The genes that have been associated with autoimmune Addison disease participate in the body's immune response. The most commonly associated genes belong to a family of genes called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders (such as viruses and bacteria). Each HLA gene has many different normal variations, allowing each person's immune system to react to a wide range of foreign proteins. The most well-known risk factor for autoimmune Addison disease is a variant of the HLA-DRB1 gene called HLA-DRB1*04:04. This and other disease-associated HLA gene variants likely contribute to an inappropriate immune response that leads to autoimmune Addison disease, although the mechanism is unknown.

Normally, the immune system responds only to proteins made by foreign invaders, not to the body's own proteins. In autoimmune Addison disease, however, an immune response is triggered by a normal adrenal gland protein, typically a protein called 21-hydroxylase. This protein plays a key role in producing certain hormones in the adrenal glands. The prolonged immune attack triggered by 21-hydroxylase damages the adrenal glands (specifically the outer layers of the glands known, collectively, as the adrenal cortex), preventing hormone production. A shortage of adrenal hormones (adrenal insufficiency) disrupts several normal functions in the body, leading to hypoglycemia, hyponatremia, hypotension, muscle cramps, skin hyperpigmentation and other features of autoimmune Addison disease.

Rarely, Addison disease is not caused by an autoimmune reaction. Other causes include infections that damage the adrenal glands, such as tuberculosis, or tumors in the adrenal glands. Addison disease can also be one of several features of other genetic conditions, including X-linked adrenoleukodystrophy and autoimmune polyglandular syndrome, type 1, which are caused by mutations in other genes.

Inheritance and family implications

From: MedlinePlus Genetics, National Library of Medicine

A predisposition to develop autoimmune Addison disease is passed through generations in families, but the inheritance pattern is unknown.

How common is it?

From: MedlinePlus Genetics, National Library of Medicine

Addison disease affects approximately 11 to 14 in 100,000 people of European descent. The autoimmune form of the disorder is the most common form in developed countries, accounting for up to 90 percent of cases.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Abdominal pain · Very frequent (99-80%)

An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) and perceived to originate in the abdomen.

Anorexia · Very frequent (99-80%)

Lack of desire to eat (loss of appetite).

Autoimmunity · Very frequent (99-80%)

The occurrence of an immune reaction against the organism's own cells or tissues.

Constipation · Very frequent (99-80%)

Infrequent or difficult evacuation of feces.

Decreased circulating cortisol level · Obligate (100%)

Abnormally reduced concentration of cortisol in the blood.

Diarrhea · Very frequent (99-80%)

Abnormally increased frequency (usually defined as three or more) loose or watery bowel movements a day.

Failure to thrive · Very frequent (99-80%)

Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.

Fatigue · Very frequent (99-80%)

A subjective feeling of tiredness characterized by a lack of energy and motivation.

Other findings in the same source

From: Orphanet

Additional reported features include Hyperpigmentation of the skin (Very frequent (99-80%)); Hypotension (Very frequent (99-80%)); Increased circulating ACTH level (Very frequent (99-80%)); Muscle weakness (Very frequent (99-80%)); Nausea and vomiting (Very frequent (99-80%)); Primary adrenal insufficiency (Obligate (100%)); Weight loss (Very frequent (99-80%)); Abnormality of the axillary hair (Frequent (79-30%)); Abnormality of the pubic hair (Frequent (79-30%)); Androgen insufficiency (Frequent (79-30%)). This is a selected summary, not a complete description of the condition.

Which doctor should you see?

The suggested department for discussing Autoimmune Addison disease is Endocrinology, with a endocrinologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Which hormone or metabolic finding is important in this case?
• How should test timing and current medicines be taken into account?
• What follow-up would show whether the care plan is working?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Autoimmune Addison disease. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.