Endocrine Overview 6 Flashcards
What are the two main pathologies that affect the posterior pituitary?
- Diabetes Insipidus (DI)
- SIADH (opposite of DI)
What is DI?
- Physiologic imbalance of water secondary to ADH deficiency or inaction
- RARE
Normally, ADH stimulates the distal tubules of kidneys to reabsorb water. Without it, what happens?
- water moves through kidneys and is not reabsorbed
- Results in excretion of large amounts of dilute urine.
How does DI compare to DM?
unlike urine in DM, urine in DI contains no glucose
Clinical manifestations of DI are increased:
- urination
- dehydration
- fatigue
- irritability
- polydipsia
- nocturia
When can a person with DI die quickly?
- unconscious or confused
- unable to respond appropriately to thirst mechanism to maintain hydration
What are the types of DI?
- Central DI
- Nephrogenic DI
Which is the most common type of DI?
Central
What causes Central DI?
idiopathic OR secondary to
- head trauma
- autoimmune dysfunction
- infection
- aneurysm
- genetic
Nephrogenic DI can arise from:
- medications
- alcohol
- electrolyte imbalance
- disease of renal system
Nephrogenic DI: which medications can cause this?
- psychotropics
- corticosteroids
Nephrogenic DI: Why might alcohol play a role?
Think of breaking the seal
How is DI managed medically?
- exogenous replacement of ADH with ADH (vasopressin) or synthetic derivative
- administration of diuretics
If a pt is taking ADH, what must be monitored?
side effects related to water intoxication, which can lead to fluid overload
SIADH =
Syndrome of Inappropriate Secretion of ADH
What happens with SIADH? (Overall)
Excess or inappropriate secretion of ADH results in marked retention of water
What are some sx of decreased urine output?
- HA
- confusion
- lethargy
- decreased urine with low sodium
- seizures
- muscle cramps
- vomiting
- diarrhea
- weight gain
What is the most common cause of SIADH?
Ectopic ADH production by malignancies
What types of signs predominate with SIADH? Why?
- Neurologic/neuromuscular
- directly related to swelling of brain tissue and sodium changes within neuromuscular tissues
SIADH in the acute care setting
Will be on strict fluid restrictions
First aim of tx for SIADH
- correction of life threatening sodium imbalance
- followed by correction of underlying cause
