Signs and Symptoms of Addison's Disease
The classic signs and symptoms of Addison's disease include fatigue, weight loss, hyperpigmentation of skin and mucous membranes, salt craving, hypotension, nausea, vomiting, and electrolyte abnormalities (hyponatremia and hyperkalemia). 1, 2
Common Clinical Manifestations
General Symptoms
- Fatigue and weakness (often severe)
- Anorexia (loss of appetite)
- Weight loss
- General malaise
- Dizziness or lightheadedness (due to hypotension)
Skin and Mucosal Changes
- Hyperpigmentation (often uneven distribution)
- Most noticeable in sun-exposed areas, skin folds, pressure points
- Darkening of scars, knuckles, elbows, knees
- Pigmentation of oral mucosa, especially buccal mucosa and gums
- Darkening of areolae and genital skin
Gastrointestinal Symptoms
- Nausea
- Vomiting
- Abdominal pain
- Salt craving
Cardiovascular Signs
- Hypotension (especially orthostatic)
- Dizziness upon standing
Electrolyte Abnormalities
- Hyponatremia (low sodium)
- Hyperkalemia (high potassium)
- Metabolic acidosis
Psychiatric/Neurological Symptoms
- Depression
- Irritability
- Poor concentration
- Daytime somnolence
Adrenal Crisis Presentation
Adrenal crisis is a life-threatening emergency that may be the first presentation of Addison's disease 3. Signs include:
- Severe hypotension or shock
- Severe abdominal pain
- Vomiting and diarrhea
- Confusion or loss of consciousness
- Fever
- Acute electrolyte disturbances
Diagnostic Challenges
The clinical presentation of Addison's disease is often insidious with nonspecific symptoms, frequently leading to delayed diagnosis 4. Several key points to note:
- Symptoms typically develop gradually over months to years 5
- Initial symptoms may be vague and easily attributed to other conditions
- Hyperpigmentation is a specific diagnostic feature that should raise clinical suspicion 4
- Diagnosis may be precipitated by an acute stressor (like gastrointestinal infection) triggering adrenal crisis 3
Laboratory Findings
Characteristic laboratory abnormalities include:
- Low morning serum cortisol (<110 nmol/L or <4 μg/dL) 2
- Elevated ACTH levels (in primary adrenal insufficiency) 4
- Elevated plasma renin activity
- Low aldosterone levels
- Hyponatremia
- Hyperkalemia
- Hypoglycemia (in some cases)
Pitfalls to Avoid
- Don't dismiss nonspecific symptoms like fatigue and weight loss without considering adrenal insufficiency
- Hyperpigmentation may be subtle in fair-skinned individuals
- Normal potassium levels don't rule out Addison's disease (may be in upper normal range) 4
- Symptoms may be masked or exacerbated by other conditions
- Adrenal crisis can be mistaken for acute abdomen, sepsis, or other causes of shock
Early recognition of these signs and symptoms is crucial for timely diagnosis and treatment to prevent potentially life-threatening adrenal crisis 6, 7.