This is due to hyposecretion of glucocorticoid and mineralocorticoid hormones. The most common causes are development of autoantibodies to cortical cells,metastatic tumours and infections. Autoimmune disease of some other glands is associated with Addison’s disease,eg.thyrotoxicosis and hypoparathyroidism. The most important effect are:
- Muscle weakness and wasting.
- Gastrointestinal disturbances.
- Increased pigmentation of the skin,especially of exposed ares,due to excess ACTH and the related melanin-stimulating hormone secreted by the anterior pituitary.
- Listlessness and tiredness.
- Hypoglycaemia.
- Mental confusion.
- Menstrual disturbances and loss of body hair in women.
- Electrolyte imbalance,including hyponatremia,low blood chloride levels and hyperkalaemia.
- Chronic dehydration,low blood volume and hypotension.
The adrenal glands have a considerable tissue reserve and Addison’s disease is not usually severely debilitating unless more than 90% of cortical tissue is destroyed,but this condition is fatal without treatment.
ADDISONIAN CRISIS.
This is characterised by sudden severe nausea,vomiting,dirrhoea,hypotension,electrolyte imbalance and,in severe cases,circulatory collapse. It is precipitated when an individual with chronic adrenocortical insufficiency is subjected to stress,eg.an acute infection.
