Calculation Of Reabsorption And Secretion Rates
â The reabsorption or secretion rate is the difference between the amount filtered across the glomerular capillaries and the amount excreted in urine. It is calculated with the following equations:
Filtered load = GFR x Excretion rate = V x Reabsorption rate = Filtered load â Excretion rate Secretion rate = Excretion rate â Filtered load
â If the filtered load is greater than the excretion rate, then net reabsorption of the substance has occurred. If the filtered load is less than the excretion rate, then net secretion of the substance has occurred.
|
Effect on GFR |
GFR = glomerular filtration rate RPF = renal plasma flow.
GFR = glomerular filtration rate RPF = renal plasma flow.
Glomerular
Glomerular
- Figure 5-4. Processes of filtration, reabsorption, and secretion. The sum of the three processes is excretion.
â Example: A woman with untreated diabetes mellitus has a GFR of 120 ml/min, a plasma glucose concentration of 400 mg/dl, a urine glucose concentration of 2500 mg/dl, and a urine flow rate of 4 ml/min. What is the reabsorption rate of glucose?
Filtered load = GFR x Plasma = 120 ml/min x 400 mg/dl = 480 mg/min Excretion = V x Urine
= 4 ml/min x 2500 mg/dl = 100 mg/min Reabsorption = 480 mg/min â 100 mg/min = 380 mg/min
Continue reading here: Reabsorption of glucose
Was this article helpful?
Why Are The Kidneys So Important
Most people know that a major function of the kidneys is to remove waste products and excess fluid from the body. These waste products and excess fluid are removed through the urine. The production of urine involves highly complex steps of excretion and re-absorption. This process is necessary to maintain a stable balance of body chemicals.
The critical regulation of the body’s salt, potassium and acid content is performed by the kidneys. The kidneys also produce hormones that affect the function of other organs. For example, a hormone produced by the kidneys stimulates red blood cell production. Other hormones produced by the kidneys help regulate blood pressure and control calcium metabolism.
The kidneys are powerful chemical factories that perform the following functions:
- remove waste products from the body
- remove drugs from the body
- balance the body’s fluids
- release hormones that regulate blood pressure
- produce an active form of vitamin D that promotes strong, healthy bones
- control the production of red blood cells
Below you will find more information about the kidneys and the vital role they play in keeping your body functioning.
Flat Plates Are Mediocre
Simple flat plates are very hard to use. The bowel overlays the kidneys, stones show as faint white spots, or not. Ribs can be in the way. I squint at the image and try to figure out where, and if, stones are. If one is highly experienced and careful, they are of modest sensitivity. I say this after having read thousands of these images over decades of practice. A recent review gives a sensitivity of 57% vs. 95% for low dose CT, and a specificity of 76% vs. 98% for low dose CT. This means that nearly 1/2 of stones will be missed.
Read Also: Can Stress Cause Kidney Infection
What Is The Evidence Behind Reporting Of The Egfr
As a result of the automatic reporting of eGFR, the clinical detection of kidney disease has significantly increased in the community.
In 2004, a clinical study involving 324 outpatients was performed to evaluate the effect of automatic laboratory reporting of eGFR with each request for serum creatinine. The effects on detection of chronic kidney disease were assessed. This automatic reporting was combined with education aimed at doctors involved in the study. The presence of an eGFR value, in conjunction with education significantly increased the detection of chronic kidney disease from 22.4% to 85.1% of patients. However, further research needs to be conducted regarding the significance and longer term outcomes resulting from this improved detection of chronic kidney disease. Last but not least, if the eGFR is normal, but there are other abnormal investigation results , the GFR should be calculated.
What Is Kidney Transplantation
Kidney transplantation involves placing a healthy kidney into your body where it can perform all of the functions that a failing kidney cant. Kidneys for transplantation come from two sources: living donors and deceased donors. Living donors are usually immediate family members or sometimes spouses. This is possible because a person can live well with one healthy kidney.
You May Like: Is Apple Cider Vinegar Good For The Kidneys
How To Count Kidney Stones
The aims of stone prevention are to reduce the number of new stones formed, and to reduce the growth of stones in kidneys by lowering supersaturation. This means we gauge our success by counting and measuring stones.
Mostly, radiologists measure and we count.
That is why I wrote this article. Ultimately, physicians are responsible for counting, but patients can help a lot.
Moneylender and his Wife , painted in 1514, hangs in the Musee du Louvre, Paris. Massys was the first important painter of the Antwerp school.
How Is Kidney Failure Diagnosed
Doctors use a variety of tests to measure kidney function and diagnose kidney failure. If your doctors suspect you may be at risk for kidney failure, they may recommend:
- Blood tests, which can show how well the kidneys are removing waste from the blood.
- Advanced imaging, which can show kidney abnormalities or obstructions .
- Urine tests, which measure the amount of urine or specific substances in the urine, such as protein or blood.
Read Also: Is Ibuprofen Metabolized In The Kidneys
Keeping Your Kidneys Healthy
Well-functioning kidneys are essential to your overall health. Early detection of kidney disease can be life-saving. Medication and changes to lifestyle, along with an early referral to a kidney specialist, can prevent or delay kidney failure.
If you are at increased risk of chronic kidney disease, talk to your doctor about having a regular kidney health check.
Are Dietary Changes Needed
In general, people with one healthy kidney dont need special diets. However, its always good to:
- have a healthy well-balanced diet
- reduce your salt intake
Dietary restrictions arent usually necessary for people who have received a transplanted kidney but its still worth following a healthy diet and watching your salt intake. However, you will probably be advised to avoid fresh grapefruit or grapefruit juice because they can interfere with certain medications. If you are advised by your kidney consultant to make specific changes to your diet, ask to be referred to the renal dietitian and follow their advice.
For more information about diet and kidney disease take a look at our dietary hints and tips.
Don’t Miss: Is Apple Cider Vinegar Good For Kidneys
What Is Done To Prevent Rejection
To allow the transplanted kidney to survive in your body, you will be givenmedicines for the rest of your life to fight rejection. Each person mayreact differently to medicines.
New antirejection medicines are continually being developed and approved.Your healthcare team will tailor medicine regimes to meet your needs.
Usually several antirejection medicines are given at first. The doses ofthese medicines may change often, depending on your response. Becauseantirejection medicines affect the immune system you will be at higher riskfor infections. A balance must be maintained between preventing rejectionand making you very susceptible to infection.
Some of the infections you will be especially at risk for include oralyeast infection ,herpes, and respiratory viruses. Avoid contact with crowds and anyone who has aninfection for the first few months after your surgery.
Your thoughts matter to us. Join our community today.
Johns Hopkins Medicine Virtual Advisors is a group ofindividuals who share their insights about the Johns Hopkins careexperience. One to two times per month, Virtual Advisors receive a link toshort, interactive surveys. All responses are confidential.
What Do Kidneys Do
One of the main jobs of the kidneys is to filter the waste out of the blood. How does the waste get in your blood? Well, your blood delivers nutrients to your body. Chemical reactions in the cells of your body break down the nutrients. Some of the waste is the result of these chemical reactions. Some is just stuff your body doesn’t need because it already has enough. The waste has to go somewhere this is where the kidneys come in.
First, blood is carried into the kidneys by the renal artery . The average person has 1 to 1½ gallons of blood circulating through his or her body. The kidneys filter that blood about 40 times a day! More than 1 million tiny filters inside the kidneys remove the waste. These filters, called nephrons , are so small you can see them only with a high-powered microscope.
Page 1
Also Check: Can Seltzer Water Cause Kidney Stones
How Many People Have Four Kidneys
More than realise it. People with extra kidneys are often oblivious to their excess baggage, and only discover it after an ultrasound scan or surgery for a more urgent medical problem. Laura Moon, an 18-year-old from Whinmoor near Leeds, heard of her bonus kidneys during an ultrasound to investigate recurrent stomach pains. Her case is particularly unusual, as each of her kidneys appears to be fully formed, at around 11cm long.
“It’s extremely rare for additional kidneys to be complete. One in a million is probably about right,” says Niaz Ahmad, a transplant surgeon at St James’s University Hospital in Leeds. “I’ve seen thousands of kidneys and I’ve never seen this.”
The condition is caused by a glitch in the first trimester, when the developing kidneys split in two. It is more common for these “duplex kidneys” to split only partially, or to grow a second ureter . Moon is having tests to check her four kidneys all work properly. If they do, she may be able to donate one or two.
Duplex kidneys occur in 1% of the population, the most common complication being infections caused by urine flowing back up to the ureter. But some patients have been delighted with their extra organs. Two Latvian brothers found to have four kidneys each said it explained why they were able to drink their friends under the table.
Protecting Your Single Kidney From Injury
If you have a single kidney, injuring it can be a big problem because there isnt another one to compensate. If the injury is severe and your kidney stops working completely, you would need dialysis or a kidney transplant to survive.
To avoid this, its very important to protect your single kidney from injury. Avoid contact sports that could lead to kidney injury. These include:
- boxing
- bungee jumping
- skydiving
Over the long term, unless your kidney gets injured, loss of function in your single kidney is usually very mild and unnoticeable.
Most people with a single kidney dont need to follow a special diet, but like people with two kidneys, you should eat a healthy balanced diet.
Staying normally hydrated and drinking when thirsty is better than overhydration or dehydration.
If you have a single kidney because you had a transplant or if you have kidney disease, you may need to limit the amount of sodium, phosphorous, and protein in your diet. This is because your kidney cant remove them from your blood very well, so they build up.
You may also have to limit the amount of fluids you drink.
Talk to your healthcare provider about your nutritional needs and dietary restrictions.
Also Check: Pineapple Juice And Kidney Stones
What Is It Like To Live With One Kidney Instead Of Two
Your kidneys filter out waste and extra fluid from your blood so it can be excreted from your body in your urine.
One kidney can filter enough blood to keep your body functioning normally. This is why you can survive and be healthy with only one kidney.
The recommendations for healthy living if you have only one kidney are basically the same for people with two kidneys. They include:
Your kidneys play a role in maintaining fluid balance in your body, keeping protein in your blood, and controlling your blood pressure.
If your kidneys stop working, you may:
- lose protein in your urine
- retain fluid
Most people with a single kidney live a normal life without developing any long- or short-term problems.
However, the risk of developing mild high blood pressure, fluid retention, and proteinuria is slightly higher if you have one kidney instead of two. This is because a second kidney can compensate and make up for a kidney that has lost some function.
Since it has no backup, the loss of function of a single kidney could lead to proteinuria, fluid retention, or high blood pressure earlier than if you had two kidneys.
How Is A Creatinine Test Done
There are two main ways doctors use creatinine tests to measure kidney function:
-
Urine tests. Creatinine clearance can be pinpointed by measuring the amount of creatinine in a sample of pee collected over 24 hours. For this method, you store all your urine in a plastic jug for one day and then bring it in for testing. This method is inconvenient, but it may be necessary to diagnose some kidney conditions.
-
Blood tests.Doctors can estimate GFR using a single blood level of creatinine, which they enter into a formula. Different formulas take into account your age, sex, and sometimes weight and ethnicity. The higher the blood creatinine level, the lower the estimated GFR and creatinine clearance.
For practical reasons, the blood test method for GFR is used far more often than the 24-hour urine collection test for creatinine clearance. But urine collections may still be useful in people who have large muscle mass or a marked decrease in muscle mass.
Also Check: Can Grape Juice Change Urine Color
Growing Up With One Kidney
It is true, you can live with only one kidney. Some people are born with only one because the other one did not grow properly. Other times, the two kidneys touch each other when they are first growing and join together, making one kidney shaped like a horseshoe. People with these types of kidneys have to be very careful because they might get sick more easily than someone who has two kidneys.
Stages Of Kidney Disease In Children
Please note: The American Kidney Fund is committed to ensuring that every person receives health care that is fair, equitable and of the highest quality. The estimated glomerular filtration rate is an estimate of how well your kidneys are working. Currently the test considers your age, sex and race, among other things. A task force led by the National Kidney Foundation and the American Society of Nephrology has made recommendations to remove Black race as a factor in the eGFR calculation. The task force received input from patients, the community and kidney disease experts, including AKFs Medical Advisory Committee, to reduce bias in kidney function testing. AKF is reviewing the NKF-ASN recommendations and will update its outreach and educational programs ongoing as additional information and evidence evolves.
Kidney disease in children is diagnosed the same way it is in adults. A urine test, blood test, imaging test, or kidney biopsy can help determine if something is wrong with the kidneys.
The eGFR blood test shows how well the kidneys are working. The stages of kidney disease are decided by a persons eGFR. eGFR can be used to diagnose a childs stage of kidney disease once the child reaches age two.
You May Like: Reducose Weight Loss
How Can You Protect Your Kidneys
Monitoring
Your doctor should monitor your kidney function by checking your blood pressure and testing your urine and blood once a year.
Controlling Blood Pressure
If your blood pressure is above normal, you should work with your doctor to keep it below 130/80. Great care should be taken in selecting blood pressure medicines for people with a solitary kidney. Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are two classes of blood pressure medicine that protect kidney function and reduce proteinuria. But these medicines may be harmful to someone with renal artery stenosis , which is the narrowing of the arteries that enter the kidneys. Diuretics can help control blood pressure by removing excess fluid in the body. Controlling your blood pressure may require a combination of two or more medicines, plus changes in diet and activity level.
Eating Sensibly
Avoiding Injury
What Is Renal Function What Does Gfr Mean
Your health care team may talk about the work your kidneys do in terms of âkidney functionâ. If you have two healthy kidneys, you have 100 percent of your kidney function. This is more than you really need. Some people are born with only one kidney and are still able to live a normal and healthy life. Many people donate a kidney for transplantation to a family member or friend and continue to have a relatively normal kidney function. Small declines in renal function do not necessarily cause a problem.1
However, many people with reduced kidney function have a kidney disease that will worsen over time. Serious health problems occur when kidney function declines to less than 25 percent. If it drops below 10 to 15 percent, a person cannot live long without some form of renal replacement therapy â either dialysis or transplantation.1
If you know your current blood creatinine level, you can use our GFR Calculator to estimate your kidney function.
The GFR is used for defining the stages of chronic kidney disease.
Also Check: Pop And Kidney Stones
Pcr Assay And Calibration
Pcr levels were measured in a single laboratory on a Hitachi 7600 analyzer using the Jaffeâs kinetic method, which was described elsewhere . To ensure that our Pcr values were calibrated equally to the MDRD study, we randomly selected 57 fresh-frozen plasma samples from our specimens and analyzed them in both our laboratory and the Cleveland Clinic Laboratory. The Pcr value that was measured by our laboratory can be calibrated to the Pcr value that was measured by the Cleveland Clinic Laboratory, which used a CX3 analyzer , using a linear regression equation: CX3 Pcr = â15.91 + 1.32 à Hitachi Pcr .