QuestionSBA
QuestionChoice
Thyrotoxicosis can result in sweating, palpitations, anxiety, and hypertension. However, this patient has normal thyroid function tests, and no clinical features of hyperthyroidism, such as tremor, diarrhoea, or a goitre.
53185
d
Thyroxine
QuestionChoice
This patient has likely got a pheochromocytoma which is a catecholamine-secreting tumour in the adrenal medulla. Excess of circulating catecholamines result in hypertension, headaches,  flushing, palpitations, and anxiety.
53182
a
Adrenaline and noradrenaline
QuestionChoice
Vasopressin, also known as anti-diuretic hormone, is essential for enabling the reabsorption of free water from the collecting duct in the nephron through aquaporin channels. Excess vasopressin results in excessive free water reabsorption, and a classical euvolaemic hyponatraemia as seen in SIADH. Low sodium results in non-specific symptoms, such as confusion and lethargy, and, if very low, seizures. This patient's bloods are normal, and there are no clinical features suggestive of low sodium.
53183
b
Vasopressin
QuestionChoice
Excess growth hormone, usually from a pituitary adenoma, results in acromegaly. Pituitary tumours can cause headaches, and excessive growth hormone may result in hypertension, as seen in this case. However, acromegalous features are absent in this patient, such macroglossia, prognathism, changes in physical appearance, and growing hands/feet.
53184
c
Growth hormone
QuestionChoice
Excess cortisol leads to Cushing's syndrome, which is associated with hypertension. However, other features of Cushing's syndrome are notably absent, such as proximal weakness, striae, central adiposity, and thinning/bruising of the skin. Cushing's disease refers to Cushing's syndrome secondary to a pituitary tumour, whilst Cushing's syndrome is excess cortisol of any cause, including secondary to exogenous steroid use.
53186
e
Cortisol
QuestionComment
i think it should be more clear that these symptoms are episodic - phaeo wouldn't typically have constant headaches, hypertension and sweating
23476
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subscriber
Axillary Gas
Concept
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# Summary
 

A pheochromocytoma is a catecholamine-secreting tumour originating in the chromaffin cells of the adrenal medulla, while a paraganglioma arises in sympathetic nerve tissue elsewhere in the body. These tumours commonly manifest between the 3rd and 5th decades of life, with an incidence of 0.5 to 2 in 1,000 hypertension patients. They may present with episodic hypertension, anxiety, weight loss, palpitations, among other signs and symptoms. Symptoms can be precipitated by stress, exercise, and certain medications. Diagnostic investigations focus on confirming catecholamine excess with plasma and urinary metanephrines tests. CT and MRI scans are also performed to locate the tumour. Management includes surgical resection, preceded by alpha blockade with phenoxybenzamine to prevent hypertensive crises.
 

# Definition
 

A pheochromocytoma is a catecholamine-secreting tumour that originates in the adrenal medulla. When a similar tumour arises in sympathetic nerve tissue elsewhere in the body, it is termed a paraganglioma.
 

# Epidemiology
 

Pheochromocytomas and paragangliomas occur in between 0.5 and 2 in 1,000 patients diagnosed with hypertension. The condition most commonly manifests between the 3rd and 5th decades of life.
 

# Aetiology
 

The aetiology of pheochromocytoma and paraganglioma is multifactorial and can be sporadic or hereditary. Multiple genes are implicated in familial cases, such as RET, VHL, NF1, and SDH.
 

# Signs and Symptoms
 

The clinical presentation can vary, with the following symptoms commonly reported:
 

 - Episodic hypertension
 - Anxiety
 - Weight loss
 - Fatigue
 - Palpitations
 - Excessive sweating
 - Headaches
 - Flushing
 - Fever
 - Difficulty breathing (dyspnea)
 - Abdominal pain
 

Physical examination may reveal:
 

 - Hypertension
 - Postural hypotension
 - Tremor
 - Hypertensive retinopathy
 

Symptoms can be precipitated by stress, exercise, surgery, straining, and certain medications like beta blockers, anaesthetic agents, and opiates.
 

# Differential Diagnosis
 

The differential diagnosis for pheochromocytoma includes:
 

 - **Anxiety disorders:** Manifest with anxiety, palpitations, sweating, but lack the characteristic episodic hypertension of pheochromocytoma.
 - **Hyperthyroidism:** Features weight loss, tremor, palpitations, but typically includes symptoms like heat intolerance and changes in hair and skin texture.
 - **Essential hypertension:** Chronic high blood pressure without an identifiable secondary cause. It lacks the episodic nature of pheochromocytoma.
 

# Investigations
 

The evaluation of suspected pheochromocytoma involves confirming catecholamine excess and identifying the tumour's location. This includes:
 

 - Plasma metanephrines testing followed by urinary metanephrines.
 - Adrenal imaging should be pursued only after biochemical confirmation. CT of the chest, abdomen, and pelvis is the modality of choice, followed by MRI if needed.
 - Extra-adrenal pheochromocytomas can be identified using specific imaging studies such as iodine-labeled metaiodobenzylguanidine (MIBG) scans or PET scans.
 

# Management
 

The definitive treatment for pheochromocytoma and paraganglioma is surgical resection of the tumour. Preoperative management includes:
 

 - Alpha blockade with phenoxybenzamine is initiated first to prevent intraoperative hypertensive crises.
 - Beta blockade can be added subsequently if necessary, to manage tachycardia or arrhythmias after adequate alpha blockade is achieved.
 

# References
 

 [Patient.info - Phaeochromocytoma](https://patient.info/doctor/phaeochromocytoma-pro)
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Phaeochromocytoma
Topic
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Endocrinology
10697
Pheochromocytoma is a catecholamine-secreting tumour causing symptoms like hypertension, headaches, anxiety, and nocturnal sweating due to excess adrenaline and noradreanline.
A 52-year-old woman presents to her GP with a headache for a month. She has also been waking in the middle of the night feeling sweaty which is unusual for her, and has been feeling more anxious. She has reported no change to her physical appearance. On examination, her blood pressure is 167/98mmHg, and the remainder of her physical assessment is unremarkable. Blood tests show a normal white cell count, normal urea and electrolytes, and normal thyroid function.

Which of the following hormones is the most likely cause of this patient's presentation?
a