Estimation of serum creatinine.pptx

Serum Creatinine

1. ESTIMATION OF SERUM / PLASMA CREATININE ( 2-Amino-1-methyl-5 H -imidazol-4-one) Chemical formula: C 4 H 7 N 3 O Molar mass: 113.120  g·mol − 1 Appearance: White crystals

2. Overview A creatinine test is a measure of how well the kidneys are performing their job of filtering waste from blood Creatinine is a chemical compound left over from energy-producing processes in muscles Healthy kidneys filter creatinine out of the blood Creatinine exits the body as a waste product in urine A measurement of creatinine in blood or urine provides clues in determining how well the kidneys are working

3. SAM=S- Adenosyl methionine SAH=S- adenosyl homocystein

4. Creatine powder Creatine is thought to improve strength, increase lean muscle mass, and help the muscles recover more quickly during exercise. This muscular boost may help athletes achieve bursts of speed and energy, especially during short bouts of high-intensity activities such as weight lifting or sprinting At the end of the day,  creatine is an effective supplement with powerful benefits for both athletic performance and health. It may boost brain function, fight certain neurological diseases, improve exercise performance, and accelerate muscle growth Side effects might include dehydration, upset stomach, and muscle cramps

5. I mportance of Creatinine Estimation The health care provider may order a creatinine test for the following reasons: To make a diagnosis for signs or symptoms of kidney disease To screen for kidney disease among patients with diabetes , high blood pressure or other conditions that increase the risk of kidney disease To monitor kidney disease treatment or progression To monitor for side effects of drugs that may include kidney damage or altered kidney function To monitor the function of a transplanted kidney

6. Contd. a creatinine test may also be ordered for other symptoms of kidney disease, including: Nausea Throwing up A loss of appetite Tiredness and weakness Trouble sleeping Changes in how much you pee Swollen feet and ankles

7. Patient prepare A standard blood test is used to measure creatinine levels in the blood (serum creatinine). The patient may be asked not to eat (fast) overnight before the test or abstain red meat for a while. For a creatinine urine test, it may need to collect urine over 24 hours or random or on the spot in containers provided by the laboratory For either test, patient may need to avoid eating meat for a certain period before the test. If patient took a creatine supplement, there is likely need to stop use

8. CONTD. A creatinine blood test doesn’t require much preparation. Fasting isn’t necessary, eat and drink the same as normally done to get an accurate result. It’s important to tell about any prescription or over-the-counter (OTC) medications currently taking. Some drugs may increase creatinine levels without causing kidney damage and interfere with your test results. Cimetidine (Tagamet, Tagamet HB ) Non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin (Bayer) or ibuprofen (Advil, Midol ) Chemo- theraphy drugs Cephalosporin antibiotics, such as cephalexin ( Keflex) and cefuroxime ( Ceftin ) These may help while interpreting the test results

9. What is the patients expectation? For a serum creatinine test, a health care provider takes a blood sample by inserting a needle into a vein in the arm. For a urine test, there is need to provide a single sample in the clinic or collect samples at home over 24 hours and return them to the clinic

10. Methods for creatinine estimation Specimen: serum or plasma and diluted urine can be used Urine is usually diluted 1:100 or 1:200 and it is preserved with thymol or toluene only Urine stored in the refrigeratorfor up to 5-7 days is also suitable Flouride and heparin are good anticoagulants if plasma is to be used

11. Test performance The total volume of the 24hrs urine is collected and carefully measured Blood is collected mid-way on the testing day The creatinine level of both blood and urine are determined U x V/P formula is used for the estimation of the clearance

12. Procedures Most of the methods are based on reaction of creatinine in the sample with alkaline picrate reagent to produce a bright orange-red complex Modification were made to reduce interferences by some other chromogenes Aluminium silicate in separating creatinine from non-specific chromogens Another modification involve the acidification step whereby the impact of acidification of colour development is measured colorimetrically and the differences noted

13. Jaffé reaction between creatinine sample and picric acid/ NaOH indicator

14. Principle: creatinine reacts with alkaline picrate reagent to form an orange-red colour which is measured spectrophotometrically Reagents: I-saturated picric acid solution; into an amber bottle containing distilled water, place an excess picric acid -leave for a few days and the supernatant is the saturated solution (keep damp as dried is explosive) II- 10% w/v NaOH in distilled water III- creatinine working reagent: mix 10ml of the saturated picric acid solution and 2ml of the 10% NaOH (fresh always) IV- stock creatinine standard: dissolve 0.113g of pure creatinine or 0.602g of creatinine zinc chloride in 100ml of 0.1N HCL to make 10mmol/L i.e. 10,000µmol/L stable for 2 month if stored at 2-8oC Working standard: dilute the stock standard 1:50 to 200µmol/L stable for a month at 2-8oC

15. Blank Standard Test Working reagent 2.0 ml 2.0 ml 2.0 ml Distilled water 0.2 ml - - Standard (200µmol/L) - 0.2 ml - Test sample - - 0.2 ml Methodology : Set up two sets of 3 test tubes and label each as blank, standard and test Add reagents as followed: 3 . Mix well and leave for 90 minutes at room temperature 4. First reading: at 490nm zero with reagent blank 5. Into the second set of tubes, Add 50µl (0.05ml) acetic acid, 60% v/v to all 3 tubes stand at room temperature for 6-10 mint and read absorbance at 490nm after blanking as second reading 6. Subtract second readings from first readings to eliminate interference from non-specific chromogens 7. Calculation: Creatinine µ mol /L=Abs. test/Abs. std X 200

16. Results Results from creatinine in blood or urine are measured and interpreted in many ways, including the following: Serum creatinine level Creatinine move into bloodstream and is filtered at a constant rate. The amount of creatinine should be relatively stable. An increased level of creatinine may be a sign of poor kidney function. Serum creatinine is reported as milligrams of creatinine to a deciliter of blood (mg/dL) or micromoles of creatinine to a liter of blood (µ mol /L). For adult men, 0.74 to 1.35 mg/dL (65.4 to 119.3 µ mol /L) For adult women, 0.59 to 1.04 mg/dL (52.2 to 91.9 µ mol /L ) In the USA and in few European countries creatinine is usually reported in m/dl, whereas in Canada, Australia and a most European countries, µ mol /L is the usual unit as SI. One  mg/dL of creatinine is 88.4  μmol /L.

17. Some c auses of elevated creatinine level Serum creatinine levels may be slightly elevated or higher than normal due to : blocked urinary track a high-protein diet dehydration kidney problems, such as kidney damage or infection reduced blood flow to the kidneys due to shock, congestive heart failure, or complication of diabetes

18. Glomerular filtration rate (GFR) The measure of serum creatinine may also be used to estimate how quickly the kidneys filter blood (glomerular filtration rate). Because of variability in serum creatinine from one person to another, the GFR may provide a more accurate reading on kidney function. The formula for calculating GFR takes into account the serum creatinine count and other factors, such as age, race and sex. A  GFR score below 60 suggests kidney disease. The range of scores below 60 may be used to monitor treatment and disease progression.

19. Creatinine and Creatinine Clearance Creatinine is a waste product that your body constantly makes during normal muscle breakdown. Your kidneys filter creatinine from the blood into the urine and reabsorb almost none of it. The amount of blood the kidneys can make creatinine-free each minute is called the creatinine clearance. Creatinine clearance in a healthy young person is about 95 milliliters (mL) per minute for women and 120 mL per minute for men. This means each minute, that person's kidneys clear 95 to 120 mL of blood free of creatinine. The GFR can vary depending on age , gender, race and size. Generally , the creatinine clearance is a good estimation of the glomerular filtration rate.

20. Creatinine clearance Creatinine clearance is a measure of how well the kidneys filter creatinine out of the bloodstream for excretion in urine. Creatinine clearance is usually determined from a measurement of creatinine in a 24-hour urine sample and from a serum sample taken during the same time period. However , shorter time periods for urine samples may be used. Accurate timing and collection of the urine sample is important. Creatinine clearance is reported as milliliters of creatinine per minute per body surface area (mL/min/BSA). The typical range for men, 19 to 75 years old, is 77 to 160 mL/min/BSA.

21. Contd. The typical range, by age, for creatinine clearance in women is as follows: 18 to 29 years: 78 to 161 mL/min/BSA 30 to 39 years: 72 to 154 mL/min/BSA 40 to 49 years: 67 to 146 mL/min/BSA 50 to 59 years: 62 to 139 mL/min/BSA 60 to 72 years: 56- to 131 mL/min/BSA Standard measures have not been determined for older adults. Results lower than the typical range for your age group may be a sign of poor kidney function or conditions that affect blood flow to your kidneys.

22. Albumin/Creatinine Ratio Another interpretation of urine creatinine count is called the albumin/creatinine ratio. Albumin is a protein in blood. Healthy kidneys generally don't filter it out of the blood, so there should be little to no albumin found in the urine. Albumin/creatinine ratio describes how much albumin is in a urine sample relative to how much creatinine there is. The results are reported as the number of milligrams (mg) of albumin for every gram (g) of creatinine.

23. Results indicating a healthy kidney are: For adult men, less than 17 mg/g For adult women, less than 25 mg/g A higher than typical result may be a sign of kidney disease. In particular, the result may indicate a complication of diabetes called diabetic nephropathy or diabetic kidney disease.