pituitary Flashcards

1
Q

what does the anterior pituitary produce

A
  • GH*- majority of cells
  • prolactin
  • ACTH
  • TSH
  • FSH
  • LH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

waht does the posterior pituitary produce

A
  • ADH

- oxytocin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what hormone inhibits GH

A
  • somatostatin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is normal serum osmolality

A
  • 285- 295
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is normal urine osmolality

A
  • 500- 800
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is diabetes insipidus

A
  • not enough ADH
  • results in passage of large volumes of dilute urine
  • urine > 3 L in 24 hours
  • < 300 mosm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the major causes of diabetes insipidus

A
  • central- decreased secretion of ADH
  • nephrogenic- kidneys dont respond to ADH
  • usu in US d/t autoimmune destruction of ADH prod cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

si/sx of DI

A
  • polyuria, nocturia, enuria
  • intense thirst with polydipsia- up to 20 L/day
  • hypernatremia with severe dehydration
  • hypotension, tachycardia
  • dry membranes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

dx of DI

A
  • 24 hour urine collection
  • hyperNa
  • normal glucose
  • elevated BUN
  • random urine osmolality
  • plasma ADH
  • water deprivation test for DI vs. primary polydipsia
  • desmopressin challenge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how can you dx central vs nephrogenic ADH

A
  • central= low ADH

- nephrogenic= high ADH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

treatment for DI

A
  • mild- fluid intake
  • D5W
  • desmopressin for central
  • HCTZ for nephrogenic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

SIADH

A
  • too much ADH
  • promotes absorption of water
  • decreased urinary output
  • dilutional hyponatremia
  • cerebral edema possible
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

causes of SIADH

A
  • head trauma
  • pulmonary dz
  • malignancy: small cell, pancreatic
  • meningitis
  • drugs
  • genetics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

si/sx of SIADH

A
  • sometimes asymptomatic
  • HA
  • anorexia
  • N/V
  • muscle cramps
  • seizures
  • AMS/ LOC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

work up for SIADH

A
  • often incidental finding on BMP
  • high urine Na, urine osmols, spec gravity
  • hypoNa
  • elevated ADH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

treatment for SIADH in asymptomatic

A
  • fluid restriction < 1.5 L/d

- demeclocycline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

treatment for SIADH in symptomatic

A
  • 3% hypertonic solution
18
Q

sheehan syndrome

A
  • infarction/ necrosis of pituitary after severe PPH
  • usu occurs gradually 10-20 years pp
  • common in underdev countries
19
Q

si/sx of sheehan

A
  • lethargy, anorexia, weight loss
  • failed PP lactation
  • failure to resume menses weeks/mo pp
  • loss of sexual hair
20
Q

dx of sheehan

A
  • MRI: early shows enlargement, late shows empty sella

- hormone eval

21
Q

treatment for sheehan syndrome

A
  • treat adrenal insufficiency first
  • treat other hormonal def 4-6 weeks later
  • no tx for prolactin decrease
22
Q

achondroplasia

A
  • most common cause of dwarfism
  • results in asymmetric dwarfism
  • short limbs, enlarged skull
  • d/t genetic defect
23
Q

dwarfism

A
  • height 2 std dev below mean in kids

- 4”10’ and under

24
Q

causes of proportionate dwarfism

A
  • GH def
  • GH receptor mutations
  • hypothyroidism
  • turner’s
  • nutritional deficiencies
25
causes of disproportional dwarfism
- achondroplasia - spondyloepiphyseal dysplasia - diastrophic dysplasia
26
spondyloepiphyseal dysplasia
- adult ht 3-4 ft - short trunk, barrel chest - severe OA - assoc with orthopaedic issues
27
diastrophic dysplasia
- rare, autosomal recessive cause of dwarfism - short forearms and calves - limited ROM - cleft palate - deformed hands/ feet
28
what causes isolated GH deficiencies?
- sellar and parasellar tumors that destroy pituitary
29
si/sx of GH def
- severe postnatal growth failure - delayed one age - hypoglycemia - prolonged jaundice - micropenis - increased fat - high pitched voice
30
dx of GH def
- first r/o other causes of growth failure - if no other causes then order IGF-1, IGFBP-3, and bone age - if IGF-1 and IGFBP-3 are low get provocative testing - MRI to r/o structural causes
31
treatment for GH def
- SQ GH injections
32
laron syndrome
- most common cause of genetically induced GH insensitivity | - mutation in GH receptor
33
si/sx of laron syndrome
- severe postnatal growth factor - small genitalia - short limb length - prominent forehead, depressed nasal bridge - osteopenia - obesity
34
what are pts with laron syndrome immune to
- cancer - CVD - DM
35
what is the most common cause of non-pathologic short stature
- genetics | - constitutional short stature
36
steps to assessing a child who appears proportional but small
- interpret growth chart - assess child's growth potential - calculate height velocity - assess bone age - lab screenings for underlying systemic endocrine diseases
37
height velocity requiring referral in 2-4 years old
- < 2.2 in/year
38
height velocity requiring referral in 4-6 years old
- < 2 in/year
39
height velocity requiring referral in 6- puberty
- < 1.6 in/year in males | - <1.8 in/ year in females
40
how do you estimate a female childs height
- [moms ht + (dads ht -5 in)] / 2 | - done at 12-15 mo
41
how do you estimate a male childs height
- ([moms ht + 5 in) + dads height] / 2 | - done at 12-15 mo