What causes renal medullary washout?
What causes renal medullary washout?
Increased medullary blood flow in vasa recta: This flushes out the solutes accumulating and creating hypertonicity in the medulla. Hypokalemia and hypercalcemia can both cause this effect. Also called medullary solute washout.
What is renal medullary washout?
Renal Medullary Solute Washout Loss of renal medullary solutes (particularly sodium and urea) leads to reduced medullary hypertonicity, which impairs the ability of the nephron to produce concentrated urine. This condition can be secondary to any cause of chronic PU/PD.
What can cause PU PD in dogs?
In dogs some of the most common conditions that cause PU/PD are Hyperadrenocorticism (commonly called Cushing’s disease), diabetes mellitus, and kidney diseases of which there are multiple forms. In cats, some of the most common causes are diabetes mellitus, hyperthyroidism, and kidney diseases.
Why does Pyometra cause PU PD?
Loss of renal medullary hypertonicity, and as a consequence decreased concentrating ability, has been described as a cause of the polyuria in dogs with pyometra. The polyuria may also be the result of decreased sensitivity of the renal V2 receptors. In virtually all dogs PU/PD is a prominent symptom of hyperthyroidism.
What do you mean by Vasa recta?
The vasa recta of the kidney, (vasa rectae renis) are the straight arterioles, and the straight venules of the kidney, – a series of blood vessels in the blood supply of the kidney that enter the medulla as the straight arterioles, and leave the medulla to ascend to the cortex as the straight venules.
How do kidneys help save water?
The kidney conserves water by first diluting urine as it moves through the loop of Henle and then concentrating urine in the distal tubules and collecting ducts (the latter under the influence of antidiuretic hormone or ADH).
What is Pupd?
Polyuria and polydipsia (PU / PD) refer to excessive water consumption and urine production respectively. These are common clinical signs in both dogs and cats. These numbers have been established in laboratory reared dogs and may not reflect “normal” water consumption in pets. They are to be used only as guidelines.
What color is pyometra discharge?
If your dog or cat has an open pyometra there may be a foul-smelling, white- or green-colored discharge coming from her vagina, which is the infected pus draining out.
Can pyometra affect eyes?
The most common clinical signs that are present in greater than 50% of cases include lethargy, depression, anorexia, fever, excessive water intake and excessive urination. Pale mucous membranes, vomiting, diarrhea, weight loss, abdominal distension, and inflamed eyes have been reported although much less frequently.
What causes medullary solute washout in vasa recta?
Increased medullary blood flow in vasa recta: This flushes out the solutes accumulating and creating hypertonicity in the medulla. Hypokalemia and hypercalcemia can both cause this effect. Also called medullary solute washout.
What causes impaired concentration in the renal medullary interstitial compartment?
The list of causes of disorders that affect the renal medullary interstitial compartment is long and includes infections, drugs, infiltrations, precipitations, inflammatory disorders, and sickle cell anemia, among others. Because of the medullary interstitial disorder, these patients may also have a reduced urinary concentrating ability.
What happens when the medullary interstitium is washed out?
Medullary washout may occur. If the medullary interstitium has been “washed out” of solutes because of chronic severe polyuria and polydipsia for any reason, no urine concentration will occur despite the presence of endogenous vasopressin, desmopressin, and intact renal V2 receptors. These dogs are then mistakenly diagnosed as suffering from NDI.
Why does the renal medulla have a low pH?
Diseases involving the renal medulla can compromise collecting duct cells and thereby cause a low H+ -ATPase activity and also diminish NH 3 availability in the medullary interstitium. Hence, the rate of excretion of N H 4 + ions is low and the urine pH is usually close to 6.0.