preview

Nephrotic Syndrome Research Paper

Decent Essays

Nephrotic syndrome (NS) is a disease process marked by excessive loss of protein through the urine, proteinuria, which leads to decreased serum albumin, resulting in decreased capillary colloid oncotic pressure (COP) and then edema. Physiologically, the capillary COP drives fluid from the capillaries into the interstitial fluid, only in amounts that can be drained by the lymphatic system. In nephrotic syndrome, the plasma COP is so severely decreased, unmatched with interstitial COP, that fluid flows from plasma to interstitial fluid in quantities that are too high to be removed by the lymphatic system, culminating in the formation of edema. When the plasma COP begins to drop, edema can also be caused by water and sodium retention, since the …show more content…

Together, increased vasopressin and decreased ANP prompts water and sodium retention. Sodium excretion is hindered by a decreased glomerular filtration rate (GFR), caused by lowered glomerular basement membrane permeability, and increased reabsorption of sodium in the distal tubule. In cases of relapse, compensatory efforts cause sodium retention resulting in hypervolemia, decreased COP, and increased GFR. However, as the disease state progresses, GFR decreases again due to glomerular membrane permeability (Vande Walle & Donckerwolcke, 2001). Sodium reabsorption in the distal tubule occurs when Na,K-ATPase pulls sodium at the basolateral membrane, rather than performing ATP hydrolysis. The active pull of sodium at the basolateral membrane also allows for sodium’s passive passage through the apical membrane with the aid of epithelial sodium …show more content…

Successful treatment with diuretics that do not significantly affect the COP would also negate this theory. Another theory posits that the capillary walls are pathologically changed to allow for more movement of albumin into the interstitial fluid, so that a combination of sodium retention by the kidneys and capillary permeability together result in edema (Doucet, Favre, & Deschenes, 2007). In favor of the underfilling theory, sustained hypovolemic status incurred by the flow of fluid into the interstitium can lead to acute tubular necrosis, which may be the cause of decreased GFR. The overfilling theory is explained by decreased ANP that leads to an increase of cyclic guanosine 3’,5’-monophosphate phosphodiesterase (cGMP) (Cadnapaphornchai, Tkachenko, Shchekochikhin, & Schrier, 2014). Increased levels of cGMP work in opposition to ANP and cause sodium retention as well as increased plasma volume, which explains both the edema and why NS patients remain normotensive in spite of functional hypovolemia (Ni, Safai, Rishi, Baylis, & Humphreys,

Get Access