00:00 / 00:00
Medullary cystic kidney disease
0 / 5 complete
Nephronophthisis, which means “nephron wasting”, and medullary cystic kidney disease, which refers to fluid-filled sacs in the medulla, are two kidney diseases that share some similar features: they’re both genetic, they both affect the nephrons, and both can lead to kidney cysts and renal failure over time.
To help understand these diseases, let’s first take a zoomed-in look at a nephron and talk about how it works. Alright so the outer layer of the kidney is called the cortex, and this is where the glomeruli live, which is where blood is initially filtered into the nephron, as well as the proximal convoluted tubule, where some of the filtered substances are reabsorbed back into the body.
The filtered substances, or filtrate, that don’t get reabsorbed then moves down through the medulla via the descending and then ascending parts of the loop of Henle.
The filtrate then goes back to the cortex briefly in the distal convoluted tubule, and then returns back to the medulla in the collecting duct.
Zooming back out a bit, the collecting ducts in each region of the kidney - called a renal pyramid, converge on the renal papilla, which dumps fully formed urine into a minor calyx.
Inflammation of the tubules and the interstitium qualifies nephronophthisis as a tubulointerstitial nephritis, but don’t confuse this with nephritic syndrome, which is where red blood cells and protein escape in the urine as a result of damage to the glomerulus.
Copyright © 2023 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Cookies are used by this site.
USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.