Pituitary Gland disorders which is part of Endocrine System.

1. Disorders of the
Hypothalmus & Pituitary

2. Endocrine System: Anatomy
ENDOCRINE
GLANDS
 Pituitary
 Adrenal
 Thyroid
 Parathyroid
 Pancreas
 Ovaries
 Testes

3. Endocrine Glands:
Hormone Messengers

4. Endocrine System: Functions
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Maintenance & regulation of vital functions
Response to stress & injury
Growth & development
Energy metabolism
Reproduction
Fluid, electrolyte, & acid-base balance

5. Endocrine Disorders
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Pituitary / Hypothalmus
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Obesity
Pituitary adenoma
Hypopituitarianism
Diabetes insipidus
Syndrome of Inappropriate Antidiuretic
Hormone (SIADH)
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ACTH Dependent
ACTH Independent
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Primary
Secondary
Adrenal Medulla
Pheochromocytoma
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Primary Hyperparathyroidism
Secondary Hyperparathyroidism
Familial (Benign) Hypocalciuric
Hypercalcemia
Hypercalcemia of Malignancy
Hypoparathyroidism
Pseudohypoparathyroidism
Medullary carcinoma of the thyroid
Thyroid

Adrenocortical Insufficiency
(Addison’s Disease)
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Cushing’s Syndrome
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Parathyroid
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Adrenal Cortex
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Hyperthyroidism
Hypothyroidism
Goiter
Thyroid nodules & Neoplasms
Subclinical Thyroid disease
Endocrine Pancreas
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Type 1 diabetes mellitus
Type 2 diabetes mellitus
Insulinoma
Glucagonoma
Somatostatinoma

6. Hypothalamic-Hypophysial
Portal System

7. Pituitary Gland
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The master gland
Located at the base of the brain
Influenced by the hypothalamus
Directly affects function of other endocrine glands
Promotes growth of body tissue
Influences water absorption by the kidney
Controls sexual development and function

8. Pituitary Gland

10. Pituitary Gland Secretions
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Anterior Lobe Production (adenohypophysis)
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ACTH (adrenocorticotropic hormone)
TSH (thyroid-stimulating hormone)
STH (somatotropic growth-stimulating hormone)
FSH (follicle-stimulating hormone)
LH (luteinizing hormone)
PRL (prolactin)
GH (growth hormone)
MSH (melanocyte-stimulating hormone)
Posterior Lobe Production (neurohypophysis)
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ADH (vasopressin, antidiuretic hormone)
Oxytocin

11. Pituitary Disorders
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Anterior Pituitary
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Acromegaly
Giantism
Dwarfism
Posterior Pituitary
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Diabetes Insipidus
SIADH (Syndrome of Inappropriate Secretion of
Antidiuretic Hormone)

12. Pituitary Adenoma
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Benign tumor
Significant d/t
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Clinical presentation r/t
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Intracranial mass: headache, DI, vision changes
Excess/deficiency of one or more pituitary hormones
Size
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Located in an enclosed space with very limited capacity to accommodate an
expanding mass
Arise from cells thatt secrete hormones, giving rise to hormone overproduction
syndromes
Microadenomas < 10 mm – more likely to present with c/o hormone excess than local
mass effects
Macroadenomas > 10 mm – more likely to experience mass effects which can impinge
on optic chiasm producing visual impairments (bitemporal hemianopia)
Etiology (type of tissue & specific secretion)
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Oversecretion of growth hormone – Giantism & acromegaly
Oversecretion of ACTH (and glucocorticoids) – Cushing’s disease
Oversecretion of prolactin - Galactorrhea
Oversecretion of TSH, LH, FSH by tumors is rare

13. Prolactinoma
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Most common anterior pituitary disorder
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Account for 60% of all primary pituitary tumors
Symptoms
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Galactorrhea in 30-80% of women & 33% of men
Suppression of gonadal function
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Women: Amenorrhea, irregular menses, menses with
infertility,
Men: decreased libido, partial or complete impotence or
infertility
Decreased bone density

14. GH-Secreting Adenoma
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Giantism
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occurs in childhood before the closure of the
epiphyses of the long bones
Acromegaly
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Occurs in middle age, after the closure of the
epiphyses of the long bones

15. Giantism or Gigantism
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Assessment
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Overgrowth of long bones
Increased height in early
adulthood
Deterioration of mental &
physical status

16. Clinical & Lab Findings in Acromegaly
FINDING
FREQ (%)
Recent acral growth
100
Arthralgias
72
Excessive sweating
91
Weakness
88
Malocclusion
68
New skin tags
58
Hypertension
37
Carpal tunnel
44
↑ FBG
30
Abnormal OGTT
68
↑ heel pad thickness
91
↑ serum PRL
16
↑ serum phosphorus
48
↑ sella volume
96

17. Acromegaly
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Assessment
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Large hands and feet
Visual problems
Headache
Hyperglycemia
Hypercalemia
Deepened voice
Thickening and protrusion
of the jaw
Increased hair growth
Joint pain
Diaphoresis
Oily, rough skin
Menstrual disturbances
Impotence

18. ACTH-Secreting Pituitary Adenoma
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Secretion of excess cortisol as a result of
overproduction of ACTH by a pituitary adenoma
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Most common cause of spontaneous Cushing’s disease
Female to male ratio 8:1
Must be distinguished from effects caused by CRH
or ACTH arising from outside the hypothalmus or
pituitary gland and from adrenal adenomas or
carcinomas
S/S
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Local mass effects
Overproduction of cortisol

19. Hypopituitarism
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Hypopituitarism
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Panhypopituitarism
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Addisonian crisis
Diabetes insipidus
Insidious onset from progressive destruction of pituitary gland by a nonsecreting tumor or subsequent to pituitary radiation therapy
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Syndrome resulting from complete loss of all the hormones secreted by the
pituitary gland
Symptoms vary based on extent & duration of disease
Acute onset secondary to infarction or trauma  life threatening
conditions
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Refers to the loss of one or more pituitary hormones
c/o reproductive function d/t LH & FSH deficiency: amenorrhea in women;
infertility or erectile dysfunction in men
Non-specific c/o lethargy, altered bowel habits
Other causes
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Massive blood loss in childbirth – Sheehan’s syndrome
Rare genetic conditions

20. Dwarfism
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Description
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The hyposecretion of
growth hormone (GH) by
the anterior pituitary gland
Dwarfism occurs in
childhood
Assessment
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Retarded physical growth
Premature aging
Low intellectual
development
Dry skin
Poor development of
secondary sex
characteristics

21. Diabetes Insipidus
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Syndrome of polyuria resulting from the
inability to concentrate urine and conserve
water as a result of the lack of vasopressin
(antidiuretic hormone)
Clinical presentation
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Nocturia
Enuresis
Large volume of urine (10-20 L/day)
Dehydration if unable to maintain fluid intake
equal to fluid losses

22. Causes of Diabetes Insipidus
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Central – defect in the
synthesis or secretion of
ADH
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Hereditary
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Autosomal dominant
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Idiopathic
Traumatic or postsurgical
Neoplastic disease
Ischemic or hypoxic
disorder
Granulomatous disease
Infections
Autoimmune disorder
Hereditary
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Acquired
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Nephrogenic – loss of
kidney’s ability to respond to
ADH by retaining water
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Acquired
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Familial – 2 types
Hypokalemia
Hypercalcemia
Postrenal obstruction
Drugs: lithium
Sickle cell trait or disease
Amyloidosis
Increased metabolic
clearance of ADH
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Pregnancy

23. Diabetes Insipidus

Description
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The hyposecretion of
antidiuretic hormone
(ADH) & a deficiency
of vasopressin
Results in failure of
tubular reabsorption
of water in the
kidneys
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Assessment
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Polyuria of 4 - 24 L per day
Polydipsia
Dehydration
Decreased skin turgor, dry
mucous membranes
Inability to concentrate urine
A low urinary specific gravity of
1.006 or less
Fatigue
Muscle pain & weakness
Headache
Postural hypotension
Tachycardia

24. Causes of SIADH
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Tumors
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Bronchial carcinoma (small-cell)
Other carcinomas (duodenum,
pancreas, bladder, ureter,
prostate)
Leukemia, lymphoma
Thymoma, sarcoma
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Mass lesions: tumors, abscess,
hematoma
Infections: encephalitis,
meningitis
CVA
Senile cerebral atrophy
Hydrocephalus
Trauma
DTs
Acute psychosis
Demyelinating & degenerative
disease
Inflammatory disease
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Infections: tuberculosis,
pneumonia, abscess
Acute respiratory failure
Positive pressure ventilation
Drugs
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CNS disorders
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Pulmonary disorders
Vasopressin, desmopressin
acetate
Chlorpropamide
Clofibrate
Vincristin, vinblastine,
TCAs, phenothiazines
Idiopathic

Diagnosis of exclusion

25. Syndrome of Inappropriate Secretion of
ADH (SIADH)

Description

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A disorder of the
posterior pituitary gland
in which a continued
release of the antidiuretic
hormone (ADH) occurs
Results in water
intoxication
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Assessment
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Changes in LOC
Mental status changes
Weight gain
Hypertension
Signs of fluid volume
overload
Tachycardia
Anorexia
Nausea and vomiting
Hyponatremia

26. Hyponatremia: Description
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Serum sodium level < 135 meq/L
Excessive sodium loss (without water)
Excessive water gain (without sodium)
Decreased serum osmolality
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sodium shifts from ICF to ECF
fluid shifts from ECF to ICF (cellular swelling)
Most common electrolyte imbalance in
hospital setting (3% prevalence)

27. Hyponatremia: Etiologies
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Excessive sodium loss
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Prolonged diuretic
therapy
Burns
Excessive diaphoresis
GI fluid loss: prolonged
vomiting, NG suction,
diarrhea, laxative abuse,
repeated TWEs
Renal disease
Insufficient sodium
intake or absorption
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anorexia
acute alcoholism
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Excessive water gain
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Adrenal insufficiency
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excessive administration
of water PO or IV (D5W)
psychiatric disorders
with compulsive water
drinking
low aldosterone
compromises sodium
reabsorption
SIADH

dilutional hyponatremia
d/t water retention

28. Hyponatremia: Manifestations
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 Na+
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>125
asymptomatic
=120-125
nausea, malaise, abd
cramps
=115-120
headache, lethargy,
obtunded
<110-115
seizures, coma,
personality changes
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I > O,  UO
Lab values
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 urine specific gravity <
1.010
 Cl< 100 mEq/L
 Serum osmolality
< 285
Weight gainno significant edema
Fingerprinting over
sternum *

29. Causes & Effects of Hyponatremia

30. Hypernatremia: Description
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Serum sodium level > 145 meq/L
Excessive sodium gain (without water)
Excessive water loss (without sodium)
Increased serum osmolality
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fluid shifts from ICF to ECF
(cellular shrinking)
Most often a water problem
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never occurs in alert pt with normal thirst and
access to water

31. Hypernatremia: Etiologies
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Water deprivation
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unconscious
debilitated
infants
Hypertonic tube
feedings
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without adequate fluids
Insensible water losses
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without water
supplements
Inadequately diluted
baby formula
High protein diet
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Watery diarrhea
Excessive admin of
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3% saline
sodium bicarbonate
Diabetes Insipidus
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burns
hyperventilation
heat stroke
lack of ADH
Near drowning in sea
water

32. Hypernatremia: Manifestations
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Dry sticky mucous
membranes *
Neurologic (CNS)
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hyperactive DTRs
disorientation
agitation with stimulation
hallucinations
lethargy  coma
Neuromuscular
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muscle twitching
convulsions
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Extreme thirst *
VS
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 T (low grade)
 HR
 BP
Oliguria or anuria
Lab values
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 ClUrine specific gravity
> 1.015
Serum osmolality
> 295

33. Causes & Effects of Hypernatremia

34. Isotonic Fluid Loss-Excess &
Hyper/Hyponatremia