Hypoadrenalism

Definition

Definition of Hypoadrenalism
The adrenal glands are two small but very important glands, situated one above each kidney, which produce a range of hormones, or 'chemical messengers'. Underactivity of the adrenal glands is called hypoadrenalism.

Many of the symptoms of hypoadrenalism are due to a deficiency of the steroid hormone cortisol, which is a potentially fatal deficiency if left uncorrected.

Each adrenal gland consists of two parts:
an outer ring – the cortex
an inner core – the medulla.

Symptoms

Symptoms of Hypoadrenalism
The onset of symptoms in Addison's disease is usually subtle.

1. Patients often feel faint and dizzy, and often experience weakness, fatigue and weight loss. At least 50 per cent of patients complain of vague stomachaches or other gut symptoms.
2. Increased pigmentation of the skin (like a suntan) is common in Addison's disease. Some patients will have a persistent tan long after a holiday. This is due to raised ACTH levels, which stimulate pigment cells (melanocytes) in the skin.
3. Patients occasionally suffer mental problems, including depression. Some suffer joint and muscle pain.
4. Very rarely, bleeding into the adrenal glands (see Figure 1 in appendix) causes acute severe back pain. This symptom should be particularly investigated in patients receiving anticoagulants, such as warfarin (eg Marevan), which prevent blood clots.
5. In some severe infections, particularly meningococcal septicaemia, bleeding may occur into the adrenal glands.
6. The loss of cortisol results in hypotension (low blood pressure) that fails to respond to catecholamine hormones and medications (eg noradrenaline).

Causes

Causes of Hypoadrenalism

1. Primary hypoadrenalism or Addison's disease: Primary hypoadrenalism, or Addison's disease, results from failure of the adrenal glands themselves. This is usually an 'autoimmune' disease, where the immune system produces antibodies that attack tissues of the body rather than a virus or bacteria. In Addison's disease, antibodies attack the adrenal cortex, causing damage and scarring. Antibodies to the adrenal cortex can be detected in the blood of some patients.
2. Secondary hypoadrenalism or ACTH deficiency: Secondary hypoadrenalism, or ACTH deficiency hypoadrenalism, is caused by diseases of the pituitary gland, which lead to adrenal failure as a secondary effect.

Diagnosis

Diagnosis of Hypoadrenalism

1. The pigmentation of Addison's disease is characteristic, and is particularly evident on exposed or traumatised areas of the skin, such as the knuckles and elbows.
2. Occasionally, the inner wall of the cheek, which is frequently bitten, also shows pigmentation. Any scars inflicted after the onset of the disease become pigmented.
3. Patients may also have signs of organ-specific autoimmune disease. These include patches of abnormal pale skin called vitiligo and sometimes evidence of thyroid disease, such as a goitre (swelling of the neck).
4. Blood pressure control is abnormal in severe cortisol deficiency.
5. The patient may have an abnormal fall in blood pressure on standing (called postural hypotension).

Treatment

Treatment of Hypoadrenalism
Treatment is almost always life long.

1. Failure to comply with treatment may be fatal, so patients with hypoadrenalism must take some simple precautions.
2. The main problem is that the need for cortisol increases during physical stress, eg major surgery.
3. All patients would be advised to carry a warning card stating their condition and explaining that they are dependent on adrenal replacement. This may save their life in the event of coma or collapse.
4. Patients with Addison's disease should also keep extra supplies of tablets at home or when on holiday, as well as a vial of hydrocortisone that they can inject.
5. Any medical professional can administer this if the patient is unconscious or unable to take oral medication.

Prognosis

Prognosis of Hypoadrenalism
Consult with your doctor.

Prevention

Prevention of Hypoadrenalism
Consult with your doctor.