SIADH Flashcards
What is SIADH?
Increased release of ADH from the posterior pituitary
What is the impact of too much ADH?
Water reabsorption from the urine is increased (in the collecting ducts of the kidneys)- this causes hyponatraemia
What are the two potential sources of excess ADH?
Increased production by the posteior pituitary
Ecoptic ADH, most commonly from small cell lung cancer
What is serum and urine osmolality like in SIADH?
Low serum osmolality
High urine osmolality
What is the presentation of SIADH?
Headache
Fatigue
Muscle cramps
Confusion
What are the possible causes of SIADH?
Post-op after major surgery
Lung infection
Brain pathologies - head injury, stroke, meningitis
Medications - SSRIs, carbamazepine
Small cell lung cancer
HIV