Search results
Results from the WOW.Com Content Network
Glomerular filtration rate (GFR) is the volume of fluid filtered from the renal (kidney) glomerular capillaries into the Bowman's capsule per unit time. [4] Central to the physiologic maintenance of GFR is the differential basal tone of the afferent (input) and efferent (output) arterioles (see diagram).
Risk factors for kidney disease include diabetes, high blood pressure, family history, older age, ethnic group and smoking. For most patients, a GFR over 60 (mL/min)/(1.73 m 2) is adequate. But significant decline of the GFR from a previous test result can be an early indicator of kidney disease requiring medical intervention.
The primary cause of the lack of clarity surrounding the GFR levels that indicate hyperfiltration is their strong reliance on age. [12] Glomerular hyperfiltration has traditionally been characterized as an elevated whole-kidney GFR, or a GFR greater than two standard deviations above the mean GFR of healthy individuals. [2]
Tubuloglomerular feedback is one of several mechanisms the kidney uses to regulate glomerular filtration rate (GFR). It involves the concept of purinergic signaling, in which an increased distal tubular sodium chloride concentration causes a basolateral release of adenosine from the macula densa cells. This initiates a cascade of events that ...
Diagnosis of acute failure is often based on a combination of factors such as decreased urine production or increased serum creatinine. [3] Diagnosis of chronic failure is based on a glomerular filtration rate (GFR) of less than 15 or the need for renal replacement therapy. [1] It is also equivalent to stage 5 chronic kidney disease. [1]
[5] [6] Risk factors include a family history of chronic kidney disease. [2] Diagnosis is by blood tests to measure the estimated glomerular filtration rate (eGFR), and a urine test to measure albumin. [8] Ultrasound or kidney biopsy may be performed to determine the underlying cause. [5] Several severity-based staging systems are in use. [13] [14]
Many laboratories will automatically calculate eGFR when a creatinine test is requested. Algorithms to estimate GFR from creatinine concentration and other parameters are discussed in the renal function article. Unfortunately, the MDRD Study equation was developed in people with chronic kidney disease, and its major limitations are imprecision ...
In renal physiology, the filtration fraction is the ratio of the glomerular filtration rate (GFR) over the renal plasma flow (RPF). Filtration Fraction, FF = GFR/RPF, or =. The filtration fraction, therefore, represents the proportion of the fluid reaching the kidneys that passes into the renal tubules. It is normally about 20%.