Adrenal Gland Disorders II Flashcards
What is Congenital Adrenal Hyperplasia (CAH)?
An inherited group of disorders characterized by a deficiency in one of the enzymes necessary for cortisol synthesis
90% due to 21α-hydroxylase deficiency, autosomal recessive, affects 1:10,000-20,000 births.
What is the typical clinical presentation of classic CAH?
Typically diagnosed in infancy with signs such as virilisation and salt-wasting
Includes adrenal insufficiency, often around 2-3 weeks of age.
What are the two forms of CAH?
Classic CAH and Non-classic CAH
Non-classic CAH presents in adolescence/adulthood with hirsutism, menstrual disturbance, and infertility.
What is the primary diagnostic test for CAH?
Basal or stimulated 17-OH Progesterone
Increasingly supported by genetic mutation analysis.
What are the three variants of 21α-hydroxylase deficiency?
Classical salt-wasting, classical simple virilising, and non-classical hyperandrogenaemia.
What is the main treatment principle for CAH?
Timely recognition and glucocorticoid replacement
Mineralocorticoid replacement in some cases and surgical correction if necessary.
What is the function of the adrenal medulla?
It produces catecholamines such as adrenaline and noradrenaline.
What is a phaeochromocytoma?
A rare tumor of the adrenal medulla that secretes catecholamines.
What are the classical symptoms of phaeochromocytoma?
Hypertension, headache, sweating, palpitations
The classical triad occurs in up to 90% of cases.
What is the significance of the ‘10% tumor’ in phaeochromocytoma?
10% are malignant, 10% are bilateral, 10% are extra-adrenal, and 10% are familial.
What are common biochemical abnormalities in patients with phaeochromocytoma?
Hyperglycemia, low potassium levels, high hematocrit, mild hypercalcemia, lactic acidosis in absence of shock.
What is the initial approach to therapy for phaeochromocytoma?
Full α and β-blockade, starting with an α-blocker before adding a β-blocker.
What is the importance of genetic testing in phaeochromocytoma?
To identify mutations in susceptibility genes and guide family tracing and evaluation.
What are some conditions associated with phaeochromocytoma?
Multiple Endocrine Neoplasia 2 (MEN2A/MEN2B), Von-Hippel-Lindau syndrome, neurofibromatosis, tuberous sclerosis.
What is the typical incidence of phaeochromocytoma?
8 per 1,000,000 per annum, may be higher.
Fill in the blank: CAH is primarily caused by a deficiency in _______.
21α-hydroxylase.
True or False: All patients with phaeochromocytoma present with classical symptoms.
False.
What imaging techniques are used to diagnose phaeochromocytoma?
CT, MRI, MIBG scan, and PET scan.
What is a common differential diagnosis for phaeochromocytoma?
Angina, anxiety, carcinoid syndrome, thyrotoxicosis, insulinoma.
