Endocrine gland disorders Flashcards
What is the amino acid that releases the most GH?
Arginine
What are the diseases of the pituitary gland?
1) Hyperpituitarism
- Galactorrhea (prolactin)
- Cushings’s syndrome (ACTH)
- Hyperthyroidism (TSH)
- Precocious puberty (GnRH)
- Hyperpigmentation (MSH)
- Gigantism
- Acromegaly
- Syndrome of inappropriate ADH secretion
2) Hypopituitarism
- Addison (decreased ACTH)
- Myxedema (Decreased TSH)
- Diabetes insipidus (Decreased ADH)
- Dwarfism (after 4-5y of age)
- Infantilism (decreased GH and GnRH, dwarf with no sex character)
- Simmond’s disease (pan-hypopituitarism)
What are the causes of hyperthyroidism?
- In the anterior pituitary
1) Hyperplasia
2) Benign tumor (functioning “secreting hormones)
3) Carcinomas
- Extra pituitary
1) Like small cell carcinoma
What are the main causes of increased growth hormone?
1) Gigantism
- hyperplasia
2) Acromegaly
- Tumor in the pituitary gland
What is meant by gigantism?
- It is an increase in GH secretion before the closure of the epiphysis
- It could be appropriate or disappropriate, when disappropriate the span > then the height, and the lower segments are > then the upper ones
- They will have hyperglycemia due to the increased GH levels
- They will have hypogonadism it is usually hyperplastic and in such cases the eosinophilic cells are the ones who are mainly affected
What is acromegaly?
- An increase in GH levels after the closure of the epiphyseal plate, mainly due to pituitary adenoma
- They will have gynecomastia (due to the prolactin like effect of GH)
- They will have hyperglycemia (due to increased GH)
- Sexual dysfunction
- Visual disturbance (as the adenoma could obscure the optic chiasm)
What are the clinical findings in acromegaly?
1) Ape-like face
2) Prominent supra-orbital ridges
3) Proganthism (the jaw forward)
4) Teeth separation
5) Big ear, nose, tongue and lips
6) The hands are spade-like, with elongated fingers
7) The feet are enlarged, and probably they change shoes every month
8) Kyphosis of the vertebrae
What are the common causes of SIADH?
1) Small cell lung cancer (سيدة فيها S)
2) Brain Injury (due to the disruption)
3) Drugs (antipsychotic “lithium”)
What is a syndrome of inappropriate ADH secretion?
- Hyponatremia:
1) Dilution of sodium
2) ANP, which increases Na excretion in the urine
3) Decreased sodium reabsorption due to decreased renin
- Neuronal swelling due to increased osmotic pressure of the plasma, in an attempt to normative blood volume, this will lead to severe neurocognitive effects (confusion, mood swings, hallucinations, seizures, coma)
What are the investigations done for SIADH?
1) Urin osmolarity (which is high due to increased Na+ excretion)
2) Urine sodium excretion (also high)
3) Hyponatremia (low serum sodium)
What are the different causes of pan-hypopituitarism?
- AKA Simmonds’ disease
1) Sheehan syndrome (During pregnancy the Ant.pit increases in size but not vascularity, and thus if a hemorrhage occurs during deliver this could damage the whole ant.pituitary)
2) Nonfunctional adenoma (adenoma that does not secrete hormones)
What are the clinical presentations of pan-hypopituitarism?
1) Prolactin deficiency (female cannot lactate)
2) Gonadotropin deficiency (secondary hypogonadism, as the cause is not related to gland itself)
3) Secondary hypothyroidism
4) Secondary hypocortisolism
5) No hyperpigmentation (as MSH is decreased with ACTH)
6) Hypoglycemia due to decreased ACTH
7) Skin pallor (due to decreased thyroid hormone = decreased erythropoietin = decreased RBC)
What are the investigations done for hypopituitarism?
1) Serum measurement of the hormones
2) Combined insulin tolerance test (we give the hormone and see that it does not increase, in the case of ACTH and GH we give insulin, normally they should increase when we give insulin)
What is diabetes insipidus?
- Deficiency of ADH, with tasteless urine
What are the types of diabetes insipidus?
1) Central DI
2) Nephrogenic DI
3) Essential hypernatremia
