Acromegaly Flashcards
Define Acromegaly
Chronic, progressive, multi-systemic disease caused by excessive Growth Hormone (GH) secretion
Aetiology of Acromegaly
Pituitary somatotroph adenoma (95-99%)
Somatotroph hyperplasia with neuroendocrine tumours (hypothalamic or digestive) that produces GHRH
Risk factors for Acromegaly
GPR101 over-expression Multiple endocrine neoplasia type 1 syndrome Isolated familial acromegaly McCune-Albright's syndrome Carney's complex
Symptoms of Acromegaly
Excessive sweating (hyperhidrosis) Headache Enlargement of supraorbital ridges, nose, hands and feet, thickening of lips and general coarseness of features Enlarged tongue Lower jaw protrusion (prognathism) Carpal tunnel syndrome Snoring Fatigue Hypertension, arrhythmias Visual field defects Hypogonadism (due to high prolactin): reduced libido, amenorrhoea
Signs of Acromegaly on examination
Excessive tissue growth: bone, cartilage, fibrous tissue, connective tissue, organs -> organomegaly
Barrel chest, kyphosis
Splayed-like hands/fingers
Frontal bossing
Macroglossia
Broad nose
Lower jaw protrusion due to mandible growth
Investigations for Acromegaly
Oral glucose tolerance test: failed GH suppression (paradoxical rise) following an oral glucose load
IGF-1: elevated
Serum glucose, calcium, phosphate: elevated
ECG and echo: may show cardiomyopathy
MRI pituitary fossa: may show enlarged pituitary gland/tumour
Visual field and acuity assessment: may show bitemporal hemianopia
Management for Acromegaly
Trans-sphenoidal surgery first line
+ stomatostatin analogues e.g. ocreotide (short acting or monthly depot injection)
+ Dopamine agonists e.g. cabergoline
+ radiotherapy
Yearly: assess GH, IGF-1, OGTT, visual assessment, BMI
Complications of Acromegaly
Obstructive sleep apnoea Hypertension Cardiomyopathies Increased risk of cancer Diabetes Mellitus / impaired glucose tolerance
Prognosis for Acromegaly
Associated with serious complications and premature death
Better prognosis due to treatment advancement
Death from: cardiovascular disease, respiratory complications, cancer