Keywords:
- 12 year old student
- growing too tall too quickly (193cm)
- height increase last 2 years: 45cm
- gaining weight too excessively (over 150kg)
- occasional frontal headache (mass effect)
- need to pass urine frequently (too much AVP)
- visual acuity reduced
- High fasting blood sugar level
- High serum IGF-1 level
- High serum GH level
- High prolactin (stalk effect)
- MRI : Adenoma
Hypothesis:
- Excess of GH secondary to pituitary adenoma leading to gigantism which if untreated can lead to acromegaly
- Diabetes mellitus
- Prolactinemia
Extra learning issue:
Multiple Endocrine Neoplasia (MEN)
- A group of heritable syndromes
- characterized by aberrant growth of benign/ malignant tumours of the endocrine glands
- each with its own characteristic pattern
- Inherited as autosomal dominant disorders
MEN type 1:
- Wermer’s syndrome
- Manifestation:
- Hyperparathyroidism *
- Pancreatic tumours
- Pituitary adenoma
- Carcinoid tumours
- Adrenal adenomas
- Subcutaneous lipomas
- Facial angiofibromas
- Collagenomas
- Less than 1% of pituitary tumours
- Gene mutations: menin
- Screen for ZES. If positive, screen for MEN1
MEN type 2:
- MEN 2A (Sipple’s syndrome) & MEN2B
- Manifestation 2A:
- Hyperparathyroidism
- Medullary carcinoma of thyroid *
- Pheochromocytoma
- Manifestation 2B:
- Medullary carcinoma of thyroid
- Mucosal neuromas
- Marfanoid habitus (Marfan)
- Pheochromocytoma
- Ganglioneuromatosis of bowel
MEN 2B: Multiple neuromas on the lips & tongue. Marfanoid facies (look like a Marfan syndrome patient)
Multiple neuromas on the lips & tongue.
- Treatment: Total thyroidectomy with at least central lymph node dissection.
- Screening: RET coding sequence.
Other causes of hypersecretion besides MEN:
- Carney Complex
- Autosomal dominant disorder
- Characterized often by cardiac, endocrine, cutanueous, breast & skin spotty pigmentation.
- Tumour
2. McCure-Albright Syndrome (MAS)
3. Neurofibrosis
Pituitary adenoma
Classification
Functional
- hormonal secretion (prolactinoma, ACTHoma, GHoma)
Size
- Microadenoma (<1 cm)
- Macroadenoma (>1cm)
- Giant adenoma – Rare (>4cm)
Treatment of pituitary adenoma:
- Trans-sphenoidal surgery
- External radiotherapy
- Somatostatin analogues (reduce GH & IGF-1)
- Dopamine agonist (therapy for acromegaly, shrink tumour)
- Growth Hormone antagonist (Pegvisomant, bind to GH receptor & prevent dimerization)