Endocrine Emergency

Question 1

Acute adrenal insufficiency

Acute adrenal insufficiency, also termed adrenal crisis, is a life-threatening endocrine emergency brought about by a lack of production of the adrenal hormone cortisol

Answer 1

Primary adrenal insufficiency is caused by loss of function of the adrenal gland itself, for example due to autoimmune-mediated destruction of adrenocortical tissue or surgical removal of the adrenal glands or due to inborn disruption of adrenal cortisol production in congenital adrenal hyperplasia.

Secondary adrenal insufficiency is caused if the regulation of adrenal cortisol production by the pituitary is compromised, this can be the consequence of tumours in the hypothalamic–pituitary area. However, pituitary regulation of cortisol production is also switched off in patients who receive chronic exogenous glucocorticoid treatment with doses ≥5 mg prednisolone

Question 2

Clinical presentation

Answer 2

• Fatigue, lack of energy, weight loss
• Low blood pressure, postural dizziness and hypotension (≥20 mmHg drop in BP from supine to standing position), dizziness, collapse, in severe cases hypovolaemic shock
• Abdominal pain, tenderness and guarding, nausea, vomiting (in particular in primary adrenal insufficiency), history of weight loss
• Fever
• Confusion, somnolence, in severe cases delirium or coma
• Back and leg cramps/spasms are commonly reported and can be distracting if not recognised for what they are (electrolyte derangement in large muscles?)
• In primary adrenal insufficiency: generalised skin hyperpigmentation, in particular in areas exposed to mechanical shear stress (palmar creases, nipples, scars, inside of oral mucosa)
• In secondary adrenal insufficiency: alabaster-like, pale skin; dependent on underlying conditions also signs and symptoms of other pituitary axis deficiencies

Question 3

Lab findings

• Hyponatraemia (in primary and secondary adrenal insufficiency)
• Hyperkalaemia (in primary adrenal insufficiency)
• Pre-renal failure (increased serum creatinine due to hypovolaemia)
• Normochromic anaemia, sometimes also lymphocytosis and eosinophilia
• Hypoglycaemia (primarily in affected children; can cause long-term neurological deficits, if not promptly treated)

Answer 3

Investigations for suspected adrenal crisis in patients not already known to have adrenal failure:

• Drug history
• Bloods -Na, K, urea, creatinine, FBC, TSH, fT4(hyperthyroidism can trigger adrenal crisis), cortisol, plasma ACTH
• Serum/plasma renin, (aldosterone low and renin high in primary adrenal insuff)

Question 4

Management of adrenal crisis

Answer 4

• Hydrocortisone (immediate bolus injection of 100 mg hydrocortisone i.v. or i.m. followed by continuous intravenous infusion of 200 mg hydrocortisone per 24 h
• Rehydration
• Tapering of hydrocortisone can be started after clinical recovery

Question 5

Patient presenting with severe and Moderately severe, symptomatic hyponatraemia

The degree of biochemical hyponatraemia is classified in three groups:

Mild: 130–135 mmol/L

Moderate: 125–129 mmol/L

Profound: <125 mmol/L

Answer 5

• Severe symptoms: vomiting, cardiorespiratory arrest; seizures; reduced consciousness/ coma (Glasgow Coma Scale ≤8)
• Moderately severe symptoms: nausea without vomiting; confusion; headache
• Mild or absent symptoms

Question 6

Management of hyponatraemia

Patients with hyponatraemia presenting with severe symptoms. Recommended approach to the use of hypertonic sodium chloride

Answer 6

Patients with hyponatraemia treated with hypertonic saline. Recommended approach if no improvement following 5 mmol/L rise in Na+ in the first hour.

Question 7

Acute hypocalcaemia

Clinical presentation

• Symptoms of hypocalcaemia typically develop when adjusted serum calcium levels fall below ~1.9 mmol/L.
• However, this threshold varies greatly and is dependent on the rate of fall.

Answer 7

Symptoms and signs of hypocalcaemia

Peri-oral and digital paraesthesiae

Positive Trousseau’s and Chvostek’s signs

Tetany and carpopedal spasm

Laryngospasm

ECG changes (prolonged QT interval) and arrhythmia

Seizure

Question 8

Causes of hypocalcaemia

The most common cause of acute symptomatic hypocalcaemia in hospital practice is disruption of parathyroid gland function due to total thyroidectomy. Hypocalcaemia may be temporary or permanent.

Answer 8

Investigations:

Serum calcium (adjusted for albumin)

Phosphate

Parathyroid hormone (PTH)

Urea and electrolytes

Vitamin D

Magnesium

Question 9

Hypercalcaemia

• <3.0 mmol/L: often asymptomatic and does not usually require urgent correction*
• 3.0–3.5 mmol/L: may be well tolerated if it has risen slowly, but may be symptomatic and prompt treatment is usually indicated*
• >3.5 mmol/L: requires urgent correction due to the risk of dysrhythmia and coma*

Answer 9

Clinical features of hypercalcaemia:

Polyuria and thirst

Anorexia, nausea and constipation

Mood disturbance, cognitive dysfunction, confusion and coma

Renal impairment

Shortened QT interval and dysrhythmias

Nephrolithiasis, nephrocalcinosis

Pancreatitis

Peptic ulceration

Hypertension, cardiomyopathy

Muscle weakness

Band keratopathy

Question 10

Causes of hypercalcaemia

Ninety percent of hypercalcaemia is due to primary hyperparathyroidism or malignancy

Answer 10

Less common causes include:

Thiazide diuretics

Familial hypocalciuric hypercalcaemia

Non-malignant granulomatous disease

Thyrotoxicosis

Tertiary hyperparathyroidism

Hypervitaminosis D

Rhabdomyolysis

Lithium

Immobilisation

Adrenal insufficiency

Milk-alkali syndrome

Hypervitaminosis A

Theophylline toxicity

Phaeochromocytoma

Question 11

Investigations in hypercalcaemia

Bloods:

• Calcium adjusted for albumin
• Phosphate
• PTH
• Urea and electrolytes

Answer 11

High calcium and high PTH = primary or tertiary hyperparathyroidism*

High calcium and low PTH = malignancy or other less common causes

(*Familial hypocalciuric hypercalcaemia may be misdiagnosed as primary hyperparathyroidism due to hypercalcaemia with inappropriately normal or raised PTH. However, the hypercalcaemia is not usually severe and it is less likely to present as an emergency)