Adrenal Gland pathology Flashcards
Adrenal Gland Location, size and composition
Bilateral
4-5 grams each
Sit superior and medial to upper pole of kidneys
Composed of outer cortex and central medulla
Adrenal Cortex zones (3)
Zone glomerulosa
Zone fasciculata
Zone reticular
Zone glomerulosa
Mineralcorticoids
Aldosterone
Zone fasciculata
Glucocorticoids
Cortisol
Zone Reticularis
Sex steroids
Glucocorticoids
Adrenal Medulla
Central core
Innervated by pre-synaptic fibres from sympathetic nervous system
Neuroendocrine (chromaffin) cells
- secrete catecholamines
Adrenocortical Pathology - Hyperfunction
Hyperplasia
Adenoma
Carcinoma
Adrenocortical Pathology- hay-function
Acute
- Waterhouse-Friderichsen
Chronic
- Addison’s Disease
Adrenocortical hyperplasia aetiology
Congenital
Acquired
Congenital Adrenocortical Hyperplasia
Autosomal Recessive
Deficiency/ lack of enzyme required for steroid biosynthesis
Congenital Adrenocortical Hyperplasia Pathophysiology
Altered biosynthesis (due to deficiency/ lack of enzyme) leads to increased androgen production
- masculinisation
- precocious puberty
Reduced cortisol stimulates ACTH release and cortical hyperplasia
Acquired Adrenocortical hyperplasia
Endogenous ACTH production
- Cushings
- Ectopic ACTH
Bilateral Adrenal Enlargement
Diffuse or nodular
Adrenocortical Tumours
Adrenocortical Adenoma
Adrenocortical Carcinoma
Adrenocortical Tumour Presentation
Mainly adults (M=F)
incidental finding
Hormonal effects
Mass lesion
Carcinomas with necrosis can cause fever
Adrenocortical Adenoma
Well circumscribed, encapsulated lesions
Usually small (2-3cm)
Yellow/ brown cut surface (lipid)
Composed of cells resembling adrenocortical cells
Well differentiated, small nuclei, rare mitoses
Adrenocortical Carcinoma
Rare
More likely to be functional
Can closely resemble adenoma
Spread of adrenocortical carcinoma
Local invasion
Metastasis (usually vascular)
Peritoneum and pleura
Regional lymph nodes
Adrenocortical Carcinoma Suggestive Features
Large size (>50g, often >20cm) Haemorrhage and necrosis Frequent mitoses Lack of clear cells Capsular or vascular invasion
Hypersecretion of Adrenocortical Hormones
Primary Hyperaldosteronism
- Conn’s Syndrome
Secondary Hyperaldosteronism
Hypercortisolism
Conns’ Syndrome
Excessive production of hormone aldosterone by the adrenal cortex
Conn’s Syndrome Aetiology
usually associated with diffuse or nodular hyperplasia of both adrenal glands
Adenoma (35% ), rarely carcinoma
- Sprionolactone bodies
- Do not suppress ACTH
Conn’s Syndrome Presentation
Hypertension
Muscle Weakness
Polydipsia (abnormally intense thirst)
Polyuria( production of large volumes of urine)
Secondary hyperaldosteronism
Increased Renin
Aetiology
Decreased renal perfusion, hypovolaemia & pregnancy
Hypercortisolism Aetiology
Cushings
Exogenous
- iatrogenic (steroid therapy)
Endogenous
- ACTH dependent or independent
ACTH Dependent
- ACTH secreting pituitary adenoma
- -> Cushings
- Ectopic ACTH
- -> Small Cell Lung cancer
ACTH independent
- Adrenal adenoma or carcinoma
- Non-lesional adrenal gland atrophies
Adrenocortical Hypofunction
Primary
- Acute
- Chronic
Secondary
- Failure to stimulate adrenal cortex
- -> Hypothalamic pituitary disorder (hypopituitarism)
- Suppression of adrenal cortex
- -> Treatment with steroids
Primary Adrenocortical Insufficiency- ACUTE
Rapid withdrawal of steroid treatment
Crisis in patients with chronic adrenocortical insufficiency - due to stress (infection or not increasing dose of steroid treatment)
Massive adrenal haemorrhage
- Newborn
- Anticoagulant treatment
- DIC
- Septicaemic Infection
Primary Adrenocrotical Insufficiency- CHRONIC aetiology
Addison’s disease
Signs and symptoms appear once >90% gland destroyed
Addison’s Disease
Destruction of adrenal cortices, resulting in steroid and mineralocorticoid deficiency
Addison’s disease Aetiology
Autoimmune (90%)
Infections (TB, HIV)
Metastatic malignancy
Addisons Disease Presentation
Insidious onset manifests once significant decreases in glucocorticoid and mineralocorticoid levels
Vague Symptoms
- Weakness
- Fatigue
- Anorexia
- Vomiting
- Weight loss
- Diarrhoea
- Pigmentation (raised POMC0
Addisons Disease Biochem and Consequences
Decreased mineralocorticoids
- K+ retention, Na+ loss
- Hyperkalaemia, hyponatraemia
- Volume depletion and hypotension
Decreased glucocorticoids
- hypoglycaemia.
Addisions Disease: Crisis
Aetiology : Strress
- Infection
- Trauma
- Surgery
Presentation
- Vomiting
- Abdo pain
- Hypotension
- Shock
- Death
Adrenal medullary tumours (2)
Phaeochromocytoma
Neuroblastoma
Neuroblastoma -Epidemiology and Location
Paediatric : 40% diagnosed in infancy
40% arise in adrenal medulla
- remainder along sympathetic chain
Neuroblastoma composition
Composed of primitive appearing cells
Can show maturation ad differentiation towards ganglion cells
Neuroblastoma Outcome
Age and stage important for prognosis
Signs of poor outcome
- Amplification of N-myc
- Expression of telomerase
Phaeochromocytoma
Small vascular tumour of the inner region (medulla) of the adrenal gland
Phaeochromocytoma compositon
Neoplasm derived from chromatin cells of adrenal medulla
Secretes catecholamines.
Phaeochromocytoma genetics
Associated with MEN2 (A & B)
Phaeochromocytoma Presentation
Rare cause of secondary hypertension
Hypertension (90%)
- Paroxysmal episodes common
Complications
- Cardiac failure, infarction, arrhythmias
- CVA
Phaeochromocytoma Laboratory diagnosis
Detection of urinary excretion of catecholamines and metabolites
Range from small to large necrotic tumour masses
may see adrenal remnants on surface
K2Cr2O7 will turn tumour dark brown due to oxidation of catecholamines in tumour cell
Phaeochromocytoma Associations (location etc)
10% tumour
10% extra-adrenal
- paragangliomas
10% are bilateral
- 50% in familial cases
10% biologically malignant
- defined by metastasis
10% are not associated with hypertension
25% are familial
