Standard Operating Procedure

Transcription

1 Subject Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Index Number Lab-8764 Section Laboratory Subsection Regional and/or Affiliates Category Departmental Contact Judy Dayton Last Revised 9/7/2017 References Required document for Laboratory Accreditation by the College of American Pathologists (CAP), Centers for Medicare and Medicaid Services (CMS), CLIA and/or COLA. Applicable To Employees of the Gundersen Boscobel Area Hospital and Clinic Laboratories Detail PRINCIPLE: For the measurement of albumin, a specific antibody binds with albumin in the presence of polyethylene glycol. The albumin-antibody complexes that are formed cause increased turbidity, which is measured as absorbance at 531nm. The albumin is then quantified using a calibration curve of absorbance versus albumin concentration. The creatinine assay is based on the Benedict/Behre chemistry in which creatinine complexes with 3,5- dinitrobenzoic acid at high ph to form a colored complex which is measured at 531nm. The creatinine is then quantified using a calibration curve of absorbance versus creatinine concentration. The albumin to creatinine ratio, A/C, is then calculated. All measurements and calculations are performed automatically by the DCA analyzer, and the screen displays albumin concentration (mg/l), creatinine concentration (mg/dl or mmol/l), and albumin to creatinine ratio at the end of the assay. Objectives: 1. To provide guidelines for use of the Siemens DCA Vantage Microalbumin/creatinine testing in a laboratory setting. 2. To establish uniform testing and reporting procedures. 3. To assure that only certified operators perform this test. Clinical Significance The measurement of low concentrations of albumin, creatinine, and albumin/creatinine ratio in urine is recommended in patients with insulin-dependent (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM). This assay is intended for use in both screening for, and monitoring treatment of, microalbuminuria. Early recognition of kidney disease associated with diabetes may lead to early medical intervention with the possibility of delaying or halting future need for kidney dialysis. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 1 of 11

2 Specimen Urine specimens can be random, overnight, or 24-hour as long as no preservatives have been used. Urine specimens may be stored at 2-8 o C for up to two weeks. DO NOT FREEZE. Allow specimens to reach room temperature naturally and mix thoroughly before use. Specimen Identification: Patient identification occurs by verbal verification of the patient s name and birth date. Refer to Lab Patient Identification for procedural guidelines. Unacceptable Specimens 1. Specimens that have been frozen. 2. Specimens that are visually hemolyzed. 3. Specimens that are highly pigmented. 4. Specimens collected following strenuous activity. 5. Specimens that exhibit significant bacterial growth or if the patient shows signs of a urinary tract infection. REAGENTS/MATERIALS: DCA Systems, Hemoglobin Microalbumin/Creatinine Reagent Kit, Siemens Medical Solutions Diagnostics includes the Reagent Cartridges, Capillary Holders and Plungers. Reagent Cartridges Reagent cartridges, stored in the manufacturer sealed pouches and refrigerated at 2-8 o C, are stable until the expiration date listed on the cartridge box. Reagent cartridges can also be kept for up to three months at room temperature (15-30 o C). Cartridges cannot be returned to the refrigerator once equilibrated to room temperature. Mark the modified three month expiration date on the carton. Do not use any cartridge after the expiration date (manufacturer or modified). Upon removal from refrigerated storage, allow the reagent cartridge to warm up at room temperature for 10 minutes in the unopened foil pouch, or five minutes if removed from the foil pouch. After opening the foil pouch, the reagent cartridge must be used within 10 minutes. To open the foil pouch, tear down from the corner notch (until the entire long side of the pouch is open). Discard the reagent cartridge if any of the following conditions exist: 1. The cartridge is damaged. 2. The flexible foil pull-tab is loose or missing. 3. The desiccant bag is missing or open. 4. Loose desiccant particles are found inside the foil package. 5. If the foil package is open for more than 10 minutes. Capillary Holders Unused urine capillary holders and plungers may be saved and used with any lot or reagent cartridges. Discard the urine capillary holder if any of the following are missing from the holder: glass capillary, absorbent pad, latching mechanism, plunger. Also discard if the starch plug is missing or at the bottom of the capillary tube. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 2 of 11

3 DCA Systems Microalbumin/Creatinine Low and High Control Kit, Siemens Medical Solutions Diagnostics The control in this kit contains a stable lyophilized materials. Store control vials and reconstitution fluid vial at 2-8 o C. Reconstituted controls are stable for 3 months when stored refrigerated at 2-8 o C. Do not use beyond the manufacturer or modified expiration date. Materials needed for testing but not included in the kits are: Disposable gloves and Kimwipes. EQUIPMENT/INSTRUMENTATION: DCA Vantage Analyzer, Siemens Medical Solutions Diagnostics Includes External Barcode Scanner and Power cord. Optical Test Cartridge, Siemens Healthcare Diagnostics Calibration: The DCA Vantage analyzer is calibrated by the manufacturer. Thereafter, the instrument automatically self-adjusts during the first-time power-up and during each assay. In the event the system is unable to make appropriate internal adjustments, an error message is displayed. Each new lot of reagent cartridges has established calibration parameters determined by the manufacturer. These values are encoded onto the calibration card provided with each lot of reagent cartridges. Note: Before using a new lot of reagent cartridges, scan the calibration card into the analyzer. Before you analyze samples, the reagent cartridge barcode (containing lot number and test name) is scanned. This accesses the appropriate calibration parameter values (calibration curve) for the particular lot number of reagent cartridges in use. If no calibration curve is in the instrument for the particular lot number of cartridges in use, the instrument prompts the user to scan the calibration card. The instrument can store two calibrations for the DCA Microalbumin/Creatinine Assay. Each of two calibrations is for a different lot number. When reagent cartridges are stored and used properly, acceptable performance up to the expiration date is ensured. To verify proper functioning of the DCA System, analyze DCA Microalbumin/Creatinine controls (refer to Quality Control section). Calibration Verification/Analytical Measurement Range is validated by lab staff at six month intervals. Test levels within this linearity kit attempts to cover the complete measurement range of the test cartridge parameters. Calibration Procedure: The calibration card for Microalbumin/Creatinine reagent cartridges has data on 2 sides. You must scan the calibration card for a lot of Microalbumin/Creatinine cartridges before you can use the lot on the DCA Vantage system. Scanning the calibration card enters the information on the DCA Vantage system. 1. Locate the dot on the system next to the barcode track. 2. Locate the barcode on the calibration card. 3. Hold the card so that the barcode faces to the right. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 3 of 11

4 4. Insert the Calibration card into the top of the barcode track. 5. Hold the Calibration card gently against the right side of the track and smoothly slide the card down. A beep sounds to signal a successful scan. NOTE: If no beep sounds, repeat the scanning procedure. If you repeatedly fail to hear a beep, refer to the Troubleshooting section in the DCA Vantage Operator s Guide. 6. To return to the Home screen, select OK. 7. Repeat steps To return to the Home screen, select OK. Accessing Calibration Data: Use the Calibration Data screen to access calibration data including scan date and time, and lot number for DCA Microalbumin/Creatinine. 1. At the Home screen, select Recall. 2. At the Recall menu, select Calibration Data. The Calibration data screen displays. 3. Select Microalbumin/Creatinine. The Microalbumin/Creatinine calibration data displays. 4. Highlight the calibration data that you want to display, and select View. The Calibration Data screen displays. 5. To print the calibration data, select Print. 6. To return to the Recall menu, select Recall. DCA Vantage Maintenance: Weekly Clean the internal Barcode Window and Analyzer Exterior: 1. Turn the power off and disconnect the power cord. 2. Clean the barcode window and analyzer exterior with a lint-free cloth dampened with distilled water. 3. Reconnect the power cord after the barcode window and the exterior are clean and dry. 4. Document completed maintenance tasks on DCA Vantage Weekly Maintenance-Monthly QC Log. NOTE: If you need to disinfect the exterior of the system, expose the surface to 0.5% sodium hypochlorite for 10 minutes. Remove any liquid body fluids before disinfection. Quarterly Removing and Cleaning Cartridge Spring and Cartridge Area: 1. Turn the power off. 2. Open the cartridge compartment door as far as possible. 3. Wipe the inside surface of the compartment door and surfaces on both sides of the compartment using a lint-free cloth dampened with water. 4. Dry the surface using a clean, dry lint-free cloth. 5. Locate the cartridge return spring inside the cartridge holder. 6. Insert the tip of a straightened paper clip (or other like device) into the top hole of the spring. 7. Gently pull the metal end towards the center of the cartridge compartment to release on side of the spring from the cartridge holder. 8. Repeat step 6 to release the other side of the spring from the cartridge holder. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 4 of 11

5 9. Pull the cartridge return spring completely out of the system. 10. Clean the cartridge return spring using a lint-free cloth dampened in water. NOTE: Ensure the leaf springs are not bent or damaged while cleaning. Damaged leaf springs do not function properly. 11. Dry the cartridge return spring with a clean, lint-free cloth. 12. Using a clean, dry sponge swab (provided in cleaning kit), remove any spilled liquid from the cartridge holder. NOTE: Do not use a cotton swab. Cotton fibers that are left on the surface can interfere with the system's optical systems. 13. Rotate the cartridge holder with the compartment door partially closed to locate and remove any additional liquid. 14. Dampen a sponge swab with water. 15. Clean the cartridge holder, rotating the cartridge holder as necessary. CAUTION: Do not allow liquid to drip off the sponge swab into system. 16. Locate the vertical grooves inside the cartridge compartment. 17. Locate the front and back slots near the top of the compartment. 18. Locate the leaf spring on one side of the cartridge return spring. 19. With the leaf spring oriented toward the back of the system, complete the following steps to lower the leaf spring into system: a. Hold on to both sides of the cartridge return spring. b. Pinch the sides together and lower the spring into the system by sliding the sides of the spring between the vertical grooves in the compartment. c. Release the spring. d. Gently and carefully push down on the edge of the cartridge return spring and insert the edge into the slot. e. Repeat Step C to attach the opposite side of the cartridge return spring to the cartridge compartment. 20. Document completed maintenance task on DCA Vantage Maintenance log. Changing the Air Filter: 1. Remove the filter holder from the back of the system. Pull the holder off from the top 2. Dispose of the old air filter. 3. Place the new air filter into the filter holder 4. Place the filter holder back on the system. 5. Document completed maintenance task on DCA Vantage Maintenance log. Running the Optical Test: The DCA Vantage system is designed to run a comprehensive series of self-checks of the optical measurement system. These self-checks are run automatically during every patient and Quality Control sample. In addition, an optical test is run quarterly and/or as needed for troubleshooting problems before calling tech service. Performing an Optical Test: 1. Locate the barcode on the optical test cartridge. 2. Hold the cartridge so that the barcode faces right. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 5 of 11

6 3. Insert the cartridge into the barcode track. 4. Smoothly slide the cartridge down the barcode tract. A beep sounds to signal a successful scan. 5. Open the cartridge compartment door. 6. Hold the optical test cartridge so that the barcode faces to the right. 7. Insert the cartridge into the compartment until you hear a snap. NOTE: The cartridge is designed to fit one way into the system. 8. Close the door. The test runs 6 minutes. 9. Print the results. 10. Remove the cartridge a. Open the cartridge compartment door. b. Locate the button on the right side of the cartridge compartment. c. Push and hold down the button with your right hand. d. Gently push the plastic tab on the cartridge to the right with your left hand. This releases the cartridge. e. Pull the cartridge out of the compartment. The optical test cartridge is reusable; DO NOT discard. 11. Document task in the DCA Vantage maintenance log. Record the three readings, Mean T, SD T and Drift Max on the DCA Vantage Quarterly Maintenance Log Sheet (See attached). Compare the new values obtained with the results recorded initially for your system. Mean Transmittance (Mean T) should be within the range of to , and should not vary more than plus or minus The Standard Deviation (SD T) should be less than and the drift (Drift Max) should be less than Drift T is not recorded on the Maintenance Sheet. QUALITY CONTROL: Internal Quality Control: The DCA System performs 48 optical, electronic, mechanical, and reagent systems checks during the course of each specimen assay. These checks include calibration verification during every test. If an assay or system error occurs during any individual measurement, the system automatically reports and error message, preventing the reporting of erroneous patient results. External Quality Control: Once prepared, DCA Systems Microalbumi/Creatinine Normal & Abnormal Control material is stable for 3 months when stored refrigerated in an upright position and tightly capped at 2-8 o C, but may remain at room temperature for only 30 minutes during testing. DO NOT freeze controls or allow to remain uncapped. Control Preparation: 1. Remove the appropriate control vials and reconstitution fluid from the refrigerator just prior to reconstitution. Gently tap lyophilized material to the bottom of the vial. 2. Remove the caps from both the control vial and the reconstitution fluid dropper bottle. 3. From the reconstitution fluid vial, transfer the entire contents into the control vial using the provided transfer pipette. Do not draw the control back into the transfer pipette. Dispose of pipette. 4. Carefully replace the control vial stopper and swirl the control bottle several times. Let stand at room temperature for 15 minutes. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 6 of 11

7 5. After 15 minutes, coat all the surfaces of the control bottle by rotating and inverting the bottle. Continue mixing until the control solution is completely dissolved. 6. Remove and discard the stopper. Replace with Dropper Tip Assembly (snap it onto the vial). Date bottle. 7. Repeat the process for the next control level. Running Controls on DCA Vantage: 1. AT THE HOME SCREEN, SCAN THE CONTROL CARD TO ENTER QC MODE. You must start the control test from the Home screen; otherwise the system does not recognize that a QC test is being run. The system will not save data to memory or prompt that a QC test is due (if reminder is set). 2. Locate the control card inside the control package. Note: One side of the control card is for the low control and the other is for the high control. 3. Hold the card so that the barcode for the Low level faces to the right. Gently press the card against the right side of the barcode track (above the dot) and quickly slide the card downward past the barcode reader. 4. A beep sounds to signal a successful scan. If no beep sounds, repeat the scanning procedure. 5. The main menu screen reads "Ready" "To start a test, scan either a DCA HBA1C or DCA Microalbumin/Creatinine test cartridge." 6. Open the room temperature foil cartridge package by tearing down from the corner notch. 7. Hold the reagent cartridge so that the barcode faces to the right (above the dot). Quickly and smoothly, slide the reagent cartridge down past the barcode reader. A beep sounds to signal a successful scan. 8. Hold the glass capillary tube to the control's dropper tip and completely fill to the fill line. (NOTE: If the control solution comes into contact with the plastic of the capillary tube, discard the capillary holder and fill a new one.) 9. Squeeze any excess control material out of the dropper into the control bottle. 10. Using a kimwipe, carefully wipe any control solution off the sides of the glass capillary tube. 11. Carefully insert the capillary holder into the previously scanned microalbumin/creatinine reagent cartridge until the holder snaps into place. 12. Open the cartridge compartment door. 13. Hold the reagent cartridge so that the barcode faces to the right and insert the reagent cartridge into the cartridge compartment until a gentle snap is heard or felt. 14. Insert the plunger into the hole at the top of the capillary holder. 15. Press the plunger into the capillary holder. The plunger locks into the capillary holder. 16. Using a smooth, slow, continuous motion, pull the flexible pull-tab completely out of the reagent cartridge. 17. Close the door and dispose of the flexible pull-tab. Five seconds after the door is closed, a beep sounds and the assay begins. NOTE: If you accidentally close the door before you pull the flexible tab, you have 5 seconds to reopen the door and pull the tab. The test resumes once the door is closed. 18. Test process initiates and continues for about 6 minutes. 19. The control results display when the test is complete. Select Next to print the results. Record on the log sheet. 20. Remove the reagent cartridge from the DCA Vantage analyzer by opening the compartment door, pressing the white button down with your right hand, and then with your left hand, gently Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 7 of 11

8 push the clear tab on the cartridge to the right. This action releases the cartridge from the instrument's cartridge compartment for removal/discard into the biohazard trash. 21. Repeat steps 1-20 for the next level or to repeat the control. Frequency of Use: Run quality control specimens at least once per month and/or under the following conditions: 1. With each new lot and/or shipment of reagents. 2. Each time a calibration card is scanned. (Performing a calibration) 3. When results do not match the patient s clinical condition or symptoms. 4. Following maintenance or repair procedures. 5. Training new testing personnel and/or confirming competency of testing personnel. Acceptable Tolerance Limits: The expected values established by the manufacturer are used to assess cartridge performance. Common Errors Causing QC to Fail: 1. Inadequately mixed control solutions. 2. Air bubbles in the control sample. 3. Control material coming in contact with the plastic part of the capillary holder. 4. Excess urine on outside of glass capillary not wiped off. 5. Kimwipe touched open end of glass capillary resulting in a short sample. 6. Harsh insertion of capillary holder may dislodge the sample in the glass capillary tube causing erroneous results. 7. Scanning the wrong control barcode into the test system. 8. Deterioration of the reagent cartridge test areas due to exposure to light, ambient moisture, or heat. Corrective Action: If quality control test fall within the acceptable ranges, patient testing may continue. If a control result is out of range, troubleshoot the system by referring to the troubleshooting section of the DCA Vantage Analyzer Operator s Guide. Correct any problems identified and run the controls again. When controls are within range, then patient testing can be continued. If problems persist, call Siemens Medical Solutions Technical Care Center: Recording QC Data: External Quality Control results are recorded on the DCA Log. The optical test results are recorded on the Optical Test Log. Results will be reviewed monthly by the Lab Director. Proficiency Testing: The Gundersen Health System Laboratories are enrolled in a proficiency testing program. The director or designee reviews results. Lab-0135 Quality Assurance for Laboratory Testing is initiated for corrective action if results. Implementation 1. Open the room temperature foil cartridge package by tearing down from the corner notch. 2. Scan cartridge barcode onto analyzer. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 8 of 11

9 3. Fill capillary tube with urine. Watch to make sure urine does not flow back down the tube. 4. Using a lint-free tissue (kimwipe) carefully wipe the outside of the glass capillary tube being careful not to touch the tissue to the end of the capillary tube which could cause wicking of the sample into the wipe. 5. Inspect capillary tube for bubbles. If bubbles are obvious then repeat loading with a new capillary holder. 6. Position the capillary holder in the correct orientation for insertion into the reagent cartridge. Insert into the reagent cartridge until the holders gently snaps into place. Be careful not to dislodge the sample from the capillary tube or erroneous results may occur. Insert plunger but do not press down completely. 7. Open reagent cartridge compartment door. 8. Hold the reagent cartridge so that the barcode faces to the right and insert the reagent cartridge into the cartridge compartment until a gentle snap is heard or felt, completely depress plunger. 9. Pull the flexible pull-tab completely out of the reagent cartridge, close the door and dispose of the flexible pull-tab. (Note: If you accidentally close the door before you pull the flexible pulltab, you have 5 seconds to re-open the door and pull the tab.) 10. Test process initiates and continues for about 6 minutes. 11. The Sample Data menu screen displays when the system detects that the compartment door closes, and indicates a test in progress after the 5-second delay. Touch the Patient ID prompt and enter test ID number. 12. The Result Screen displays when the system finishes the analysis. This screen displays result values and demographics for each test. Press the Next key to print the test results onto adhesive-backed paper. 13. Review the results. 14. Remove the reagent cartridge from the DCA Vantage analyzer by opening the compartment door, pressing the white button down with you right hand, and then with your left hand, gently push the clear tab on the cartridge to the right. This action releases the cartridge from the instrument s cartridge compartment for removal/discard into the regular trash. (Discard into a biohazard container). 15. Verify results in LIS. PROCEDURE NOTES: 1. A test can be canceled at any time during the testing cycle by pressing the Cancel button. Once the test is cancelled, the sample must be discarded. 2. Calibration is performed every time the calibration card is scanned. 3. Scanning the reagent cartridge barcode allows the DCA Vantage to access the stored calibration parameter values and calibration curve for the particular lot of reagent in use. 4. A sign or a + sign displayed after a numeric test result percentage indicates that the result is within the reporting range but below or above the normal reference range. 5. An Albumin/Creatinine ratio preceded by a less than (<) sign or greater than (>) sign or (---) in the display, indicates that either the albumin and/or creatinine value is above or below the reporting range. In certain cases, no ratio is reported (---). 6. The test cartridge is designed to fit only one way into the cartridge compartment. Forcing a cartridge into the compartment may cause damage to the analyzer. 7. You can print, enter, or edit the sample data while the results are displayed. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 9 of 11

10 8. If the onboard barcode scanner cannot read a control or calibration barcode due to overall glare, Magic grand tape can be used to cover barcodes to reduce the glare. CALCULATIONS: All measurements and calculations are performed automatically by the DCA Analyzer, and the screen displays displays albumin concentration (mg/l), creatinine concentration (mg/dl or mmol/l), and albumin to creatinine ratio at the end of the assay. INTERPRETATION: Albumin: The displayed test result requires no further calculation. Albumin concentrations in the following range are reported: mg/l. The test is linear throughout this range. Creatinine: The displayed test result requires no further calculation. Creatinine concentrations in the following range are reported: mg/dl. The test is linear throughout this range. Albumin/Creatinine Ratio: The displayed test result requires no further calculation. Albumin/Creatinine Ratios can be reported in the following range: mg/g. Albumin: Creatinine Reportable range is mg/l. If result is less than 5, report as: <5 mg/l (Do not need to repeat). If result is greater than 300, report as >300 mg/l (Cannot dilute specimen for re-assay) Reportable range is mg/dl. If result is less than 15, report as <15 mg/dl. (Do not need to repeat). If result is greater than 500 mg/dl, report as >500 mg/dl. (Cannot dilute specimen for re-assay). Albumin/Creatinine Ratio: Reportable range is mg/g. If ratio is outside the reportable range, the LIS will add a comment "Unable to calculate. Urine microalbumin (or creatinine) is less than (exceeds) the reportable range for albumin (or creatinine)." LIMITATIONS: 1. Avoid using urine specimens that are visually hemolyzed or highly pigmented. 2. Urine specimens containing in excess of 2000 mg/l of albumin may give assay results within the range of the DCA System because of the antigen excess effect for direct agglutination assays. If such gross proteinuria is suspected assay the sample using a Multistix 10SG reagent strip. 3. The amount of albumin excreted in urine can vary according to changes in posture, hydration, physical activity, blood pressure, and pregnancy. 4. Test should not be performed if the sample exhibits significant bacterial growth or if patient shows signs of urinary tract infection. 5. Albumin: No cross-reactivity exceeding 5% has been found with IgG, hemoglobin, transferring, or microglobulin. Elevated glucose and urea have not been shown to affect the assay results. 6. Creatinine: Elevated glucose, urea, ascorbate, bilirubin, acetoacetate and hemoglobin have not been shown to affect the assay results. Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 10 of 11

11 7. No interference has been shown by drugs commonly found in the urine or prescribed to persons with diabetes. REVIEW AND CHANGES: This document and all attached forms should be reviewed optimally on an annual basis, with 2 years as the maximum review date. Review will be done by the Technical Leader, Supervisor, Manager, Medical Director or designated person. Changes require retyping document or form and review by the Medical Director. REFERENCES: 1. Siemens Medical Solutions DCA Microalbumin/Creatinine Reagent Kit Product Insert, Rev. A 08/ Siemens Medical Solutions DCA Microalbumin/Creatinine Control kit, Product Insert, Rev. A 03/ Siemens Medical Solutions DCA Vantage Operator s Guide, Ref Rev. A, Clinical and Laboratory Standards Institute. Laboratory Documents: Development and control; Approved Guideline Fifth Edition. CLSI document GP2-A5 (ISBN x). Clinical and Laboratory Standards Institute, 940 West Valley Road, Suite 1400, Wayne, Pennsylvania USA, Lab-8764 Urine Microalbumin/Creatinine by Siemens DCA Vantage - Boscobel Page 11 of 11