acromegaly and gigantism Flashcards
Gigantism & Acromegaly: description and MCC
Syndromes of excessive Growth Hormone
- MC: pituitary adenoma
Gigantism
Occurs before growth plate closure
Marked by:
Increased skeletal growth velocity
Stature increased
Little bony deformities
Soft-tissue swelling
Peripheral nerves enlarged - nerve damage and pain
Most common: Delayed puberty or Hypogonadotropic hypogonadism
-eunuchoid habitus: long arms + legs compared to trunk
Acromegaly: MC demographic + earliest clinical manifestions
MC: Middle aged adults
earliest clinical manifestations:
- Coarsening of facial features
- Soft tissue swelling of hands and feet
Acromegaly definition and what is it marked by
Definition:
- Disfiguring and debilitating somatic growth disorder secondary to GH hypersecretion
- Lifespan typically reduced by 10-15 years
- Mortality 2-3x of normal
Marked by:
- Bone & Soft tissue overgrowth
- Excess secretion of GH
- Subsequent elevation of IGF-1
Acromegaly Presentation
Insidious onset
MC: middle aged adults
Coarsening of facial features
Soft-tissue swelling of hands & feet
Acromegaly Symptoms
Excessive sweating *
Coarse, oily skin *
Increase in foot, hand, head size
- Pts tend to notice growth
- Spadelike hands
Doughy moist handshake*
Naso-sinus abnormalities
- snoring
Diplopia
Arthralgias & Arthropathy: *
- can see and hear clicking
- TMJ Arthritis
- Carpal tunnel syndrome
Sensation of weakness in arms and legs
Skin tags*** common
Acromegaly Signs: due to increased insulin-like growth factor 1
Coarse facial features
Frontal bossing
Joint stiffness: Hands + Knees
- spinal stenosis
- barrel chest: rib enlargement
Prognathism: Protrusion of lower mandible*
- Increased space between lower teeth
Voice changes: Deepness and huskiness
Macroglossia
IGF-1:
- increased skeletal growth
- primarily produced in the liver as a response to GH stimulation
Acromegaly Signs: due to increased GH
Hyperhidrosis face, head, hands, feet (enlargement of sweat and sebaceous glands) *
Increased soft tissue mass (hand, foot, tongue) *
Naso-sinus abnormalities = sleep apnea
Sensorimotor Polyneuropathy
Myopathy: especially proximal
Insulin resistance & Glucose Intolerance
Hypertriglyceridemia
Cardiovascular Abnormalities
HTN
Colonic Polyposis*
Hyperprolactinemia
Decreased Libido
GH:
- stimulates IGF-1 production -> growth effects
- influences fat metabolism
- anti-insulin effects -> promotes glucose production in the liver
Acromegaly signs
due to mechanical effect of tumor:
- Headache - severe
- Visual symptoms: visual field defects and decreased acuity
- Impairments of pituitary function due to compression of the tumor -> ex: hypopituitarism
Non-Pituitary Tumor secretion of GH (LESS THAN 2% RARE) can be due to
*Pancreatic cancer
*Small cell lung cancer
*Tumors of the adrenal gland
*Carcinoid syndrome
*Carcinoma of the thyroid
*Hypothalamic tumors - extremely rare
*Hamartoma, glioma, or gangliocytoma
Diagnostic Work Up for acromegaly
Diagnosed via Clinical Features + Biochemical Markers:
Serum IGF-1:
- Best for SCREENING
- High IGF- 1 levels -> useful for monitoring response to tx
Golden Standard: Oral Glucose Intolerance Test*
- Definitive dx: GH levels fail to decrease to < 1 ng/L after glucose ingestion
- Glucose should decrease GH levels
- Theory: Glucose mediates release of Somatostatin
Imaging:
- MRI & CT to assess for adenomas
- SPECT & Somatostatin Receptor Scintigraphy if etiology is not adenoma
acromegaly gold standard dx
Golden Standard: Oral Glucose Intolerance Test*
- Definitive dx: GH levels fail to decrease to < 1 ng/L after glucose ingestion
- Glucose should decrease GH levels
- Theory: Glucose mediates release of Somatostatin
Treatment for acromegaly: first line + goal
Goal: Normalizing GH & IGF-1 Levels
Surgery: First-line Therapy *
- Resect tumor
- Microadenomas (<10mm, 85%) have higher surgical cure rates than macroadenomas (>10mm, 50%)
- Successful outcome: decrease in sweating and oily skin; reverse soft tissue swelling
- N/c in bony changes
Treatment for acromegaly: second and third line
Pharmacological management
- Second-line Therapy: “SO DOPE”
- Somatostatin Analogs
- Octreotide
- Dopamine Agonist
Radiation Therapy:
- Third-line Therapy
- Indicated for non-resectable and pharmacotherapy failure
- Few adverse events
- Tumor regrowth = rare
what cannot be reversed after sucessful tx and what should be closely monitored in pts post-recovery
Bony changes (jaw malocclusions, frontal bossing) do not resolve even after successful treatment!! *
- If treatment is started before articular cartilage is destroyed, then joint symptoms are reversible
Patients with a previous colon polyp *
- continued high risk of colonic polyps and cancer
