Week 2: Addison's disease Flashcards
1
Q
Etiology of adrenal insufficiency
A
- Primary: adrenal gland destruction
- autoimmune- 70%
- tuberculosis -20%
- other - 10% - Secondary: loss of ACTH/CRH
- exogenous glucocorticoids
- cure of Cushing’s syndrome
- hypothalamic/pituitary disease
2
Q
Actions of glucocorticoids: Type 1 and Type 2 responses
A
- Type I GC receptor (aka MC receptor)
- health/wellbeing. High affinity and low capacity.
- promotes anabolism, sustains response to catecholamines, maintains lean body mass, preserves normal vascular tone, cognitive function, clearance of free water, reproductive function - Type 2 GC receptor
- illness/fasting, low affinity, high capacity
- high energy mobilization: increase blood glucose, promotes muscle catabolism, hepatic glycogenolysis and gluconeogensis
- increases insulin resistance
- modulates immune response: prevents overshooting through various mechanisms, e.g. blocking cytokines, block WBC egress from circulation, decrease lymphocytes, increase neutrophils
3
Q
Clinical features of adrenal insufficiency
A
- Chronic
- weakness, weight loss, fatigue, anorexia, nausea, vague ab pain, diarrhea, orthostatic dizziness, salt craving, depression, decrease in libido
- hyperpigmentation of skin, scars, areas of repeated trauma, vitiligo, (patients look dirty) - Acute
- myalgias/arthralgias, severe abdominal pain, nausea, vomiting, postural hypotension,
- fever, dehydration, marked hypotension, altered sensorium
4
Q
Laboratory findings in adrenal insufficiency
A
- hyponatremia
- metabolic acidosis
- hypoglycemia
- anemia: normochromic, normocytic
- eosinophilia
- hyperkalemia
- prerenal azotemia
- hypercalcemia- rare
- neutropenia
- lymphocytosis
5
Q
Diagnosis of adrenal insufficiency
A
- Acute
- clinical signs and symptoms
- serum cortisol level9 mg rise is normal. 15 normal
- cortisol15 normal, <15=AI
6
Q
Therapy for acute and chronic adrenal insufficiency
A
ACUTE
-IV hydration with normal saline
-IV glucocorticoids
CHRONIC
-glucocorticoid replacement, hydrocortisone 15mg/5mg
-mineralocorticoid replacement, fludrocortisone 0.1mg
-medalert and education: serum K= levels for adequency of fludrocortisone dose, symptoms for adequacy of hydrocortisone dose, double daily hydrocortisone dose with stress
7
Q
Primary vs secondary adrenal insufficiency: symptoms+labs
A
PRIMARY -weight loss -wasting -hyperpigmentation -hyper K+ -elevated ACTH w/ low cortisol -low cortisol with 3 day ACTH stimulation test SECONDARY -weight gain -obesity -normal pigmentation -normal K+ -low ACTH+low cortisol -normal cortisol after ACTH stimulation test for 3 days