Endocrinology - Polyuria: By Jeannette Goguen M.D. скачать в хорошем качестве

Endocrinology - Polyuria: By Jeannette Goguen M.D.

medskl.com is a free, global medical education site (FOAMEd) covering the fundamentals of clinical medicine with animations, lectures and concise summaries. medskl.com is working with over 170 award-winning medical school professors to provide content in 200+ clinical presentations. Endocrinology – Polyuria: The Bottom Line Whiteboard Animation Transcript with Jeannette Goguen, MD https://medskl.com/Module/Index/polyuria Investigating polyuria requires an organized approach: Step 1: First, confirm that the patient actually is polyuric (i.e., make more than 3 liters day), and doesn’t just have urinary frequency with a normal urine volume. Are they drinking more than 3 liters a day? If they are in steady state, fluid in = fluid out. They should have nocturia as well. Step 2: Next, find out why they are drinking so much. If they say “because, it’s good for me”, then tell them to reduce their fluid intake, and see if the urine volume drops. Step 3: With polyuria confirmed, it is time to look for a reason why. The commonest reason is an osmotic diuresis from poorly controlled diabetes mellitus. Do they have known diabetes mellitus? Risk factors for diabetes mellitus? Other symptoms like weight loss and polyphagia? Otherwise, are they on a diuretic? In the hospitalized patient, consider mannitol use, the urea load from TPN and the normal clearing of excess administered intravenous fluids. Next consider a water diuresis. There are 3 causes for water diuresis: • Psychogenic polydipsia is when the patient drinks excessively and is often associated with psychosis. • Next, in Diabetes insipidus or “DI”, the high urine output is driving the drinking. There are two forms of DI: central with loss of ADH secretion from the posterior pituitary from things like pituitary mass or following pituitary surgery OR • Nephrogenic DI, where their kidneys do not respond properly to ADH – a situation that may be congenital or linked to Lithium use, hypercalcemia, and hypokalemia. Unless the diagnosis is obvious like diabetes mellitus, hypercalcemia, hypokalemia, or after pituitary surgery, you may not be able to sort out why the patient has polyuria, and you will need to refer them to an endocrinologist to do a water deprivation test, in a controlled setting.