Addison’s disease (AD) is an autoimmune disease that results from adrenal gland dysfunction and subsequent damage. It is synonymously called primary adrenal insufficiency (PAI). The adrenal cortex is situated on the upper sides of the two kidneys in the human body and normally has important functions, including maintaining the electrolyte balance of the body. AD is a rare disease and may have a genetic predisposition. Early diagnosis and treatment are necessary as they may lead to an Addisonian crisis which can be devastating.

AD can occur at any age but most frequently presents itself during the second or third decades of life. The incidence of AD is 0.6 individuals per 100,000 individuals of the population per year. The total number of individuals affected by AD at a given time is from 4 to 11 individuals per 100,000 individuals within a population. In adults, it was observed that the common age of presentation ranges from 30 to 50 years. The disease is more commonly seen in women than in men.

Addison's disease is a disorder where there is insufficient hormones secretion by the adrenal glands.

Symptoms

AD usually manifests as a subtle and slow onset of non-specific and overlapping symptoms with several other diseases. Clinically suspected cases should be carefully observed to avoid misdiagnosis with diseases such as sepsis, shock, hypothyroidism, and infectious mononucleosis. The initial clinical symptoms include:

• Generalized weakness

• Fatigue

• Loss of weight

• Vomiting

• Nausea

• Dizziness

• Abdominal pain

• Tachycardia (a heart rate above 100 per minute)

• Postural hypotension

• Hyperpigmentation (a condition defining patches of skin getting darker in color than the surrounding areas)

Hyperpigmentation is usually generalized and most well-known in sun-exposed and pressure areas. Addisonian crisis is often characterized by the manifestation of severe dehydration, refractory hypotension (circulatory collapse that occurs when adequate blood circulation cannot be maintained during surgery in patients despite having normal blood volume), confusion, and shock.[DR1] [NA2]  The Addisonian crisis is more likely to occur in primary adrenal insufficiency than in secondary manifestations.

Diagnosis

Early diagnosis is the key to a better quality of life. The approach for diagnosis includes:

(a) Evaluation of the cortisol level

(b) Assessment of the capacity of the adrenal cortex to synthesize cortisol, and to determine whether the cortisol deficiency is related to a corticotropin (ACTH) deficiency, which in turn designates the adrenal insufficiency as primary or secondary

(c) Ascertain a treatable cause of the condition if present

Treatment

Treatment through fluid resuscitation to restore the blood volume with intravenous normal saline is required. Prompt hormone treatment in the form of hydrocortisone is advised in patients with AD. The first dose of hydrocortisone should be in the quantity of 100 mg IV bolus, succeeded by 50-100 mg IV every 6 hours over 24 hours for adrenal crisis. Whereas, in children, a reduced dose is preferred with a 50 mg (maximum- 100 mg) IV bolus, followed by 50 to 100 mg during the acute phase of AD. Steroid dexamethasone in the quantity of 4-mg IV bolus can be considered in the emergency department when emergent steroid administration is required. If stress-associated fever, infection, or other conditions are present, increased glucocorticoid secretion is further inhibited to a certain degree, the hydrocortisone dose should be enhanced. In addition, for pregnant women, particularly in the third trimester, enhanced doses of corticosteroids are required. Dextrose solution is also required immediately to restore low blood sugar levels and therapy of both glucocorticoid and mineralocorticoid is necessary. Corticosteroid drugs may be used lifelong to replace hormones cortisol as well as aldosterone[DR1] [NA2]. Highly personalized regimens and regular monitoring are required to properly manage AD. More efforts are needed to optimize the treatment of AD.