Document Description Document Type Standard Operating Procedure C-Reactive Protein (CRP) Testing Service Application General Practitioners, Version 1.0 Ratification date August 2016 Review date March 2018 Lead Author(s) Name Dr David Shukla Position within the Organisation GP Research Lead Consultation Committee Date ACE March 2017 Presented for discussion, approval and ratification to Area Clinical Effectiveness Committee (ACE) March 2017 Change History Version Date Comments 1.0 31/8/2016 1.1 17/11/2016 Draft protocol subject to review of exclusion criteria, to be circulated outside of meeting and then signed off by chair 1
Standard Operating Procedure C-Reactive Protein (CRP) Testing Effective Date: March 2017 Purpose & Scope Offer a Point-of-Care Testing (POCT) for CRP in Primary Care to reduce levels of inappropriate antibiotic prescribing in Lower Respiratory Tract infections (LRTI) presenting in Primary Care This is NOT diagnostic but is a supportive tool to help decrease uncertainty about appropriate acute LRTI management, in addition to a thorough history taking and examination Definitions & Abbreviations CRP : C- Reactive Protein POCT: Point of Care Testing LRTI : Lower Respiratory Tract Infection LIS : Local Improvement Service Items Required QuickRead go Instrument - Orion Diagnostica Quickread GO CRP Kit Quality Control Vials Grade / Qualifications Applicable to individuals who have had training in using the machine (GP s, Nurses) 2
Contents 1. Clinical Application Page 3 2. Process Page 3 3. Quality control Page 3 4. Eligible patients: Page 3 5. How to interpret the test NICE guidelines? Page 4 6. Processing Procedure Page 5 7. Maintenance Page 5 8. Quality Control Procedure Page 7 9. Results Page 7 10. Sources of error, Error messages and Unexpected high/low results Page 7-8 11. Disposal Page 9 Appendix links to additional training materials 3
1. Clinical Application Tackling high antibiotic prescribing to try to reduce antibiotic resistance is a top priority both nationally and internationally. In the UK GPs issue around 80% of all prescribed antibiotics although research shows that they only have a small impact on symptoms. Reducing unnecessary antibiotic prescribing by GPs is therefore one approach to reducing their unnecessary use overall. It has been shown that using a simple finger prick blood test called C reactive protein (CRP) can give GPs extra information and help them better target antibiotics to those people most likely to benefit from taking them. GPs using this test have shown they can reduce antibiotic prescribing by 40%. GP surgeries have to pay for using the test so this is likely to limit how many surgeries take it on. This project aims to try to make it more likely GPs will use the CRP test by using existing ways of funding to reimburse practices with the extra costs of using the test. We will assess the effect on global antibiotic use by using information about prescribing which is available for all GP practices from the NHS Business Services Authority. Under the remit of this project, reimbursement for CRP testing kits will involve clinicians adhering to protocol and completion of an anonymised data sheet. 2. Process Testing equipment: Practices taking on the service will be given access to a near patient CRP testing kit. Testing kits will also be provided initially in this pilot although a reduced reimbursement will be made where the CCG has provided the testing kits. 3. Quality control Practices will be expected to have appropriate QC procedures in place. 4. Eligible patients There is good evidence that testing those presenting with lower respiratory infection enables practitioners to better target antibiotics and reduces prescribing. In the trials LRTI was defined as an illness where cough was a prominent symptom and there was another sign or symptom of lower tract infection e.g. (sob, pain, sputum, wheeze), and no other diagnosis was suspected. There are three potential clinical scenarios presented in the table below. There is limited data on testing in other respiratory infections (sore throat sinusitis) and testing is not currently supported by good quality evidence. 4
Target population: Adults up to 65 years with cough presenting in routine general practice due to a lower respiratory infection and diagnostic uncertainty as to whether antibiotics are required. In line with NICE and PHE guidance. Inclusion Criteria the subject between 18-65 years the subject has given oral consent for the CRP test and understands rationale for the test and process the subject has a lower respiratory tract infection presenting diagnostic uncertainty the presentation is acute (21 days or less) the subject primary complaint of cough Exclusion Criteria the subject has a definitive indication for antibiotics (without diagnostic uncertainty) Allergy to antibiotics Under follow-up from chronic disease (COPD) Moderate to severe asthma Ischaemic Heart Disease Patients with non-respiratory acute diagnosis (urinary tract infection, otitis media, other infection with local signs) Acute pneumonia/respiratory tract infection requiring admission to hospital You may find it helpful to use a clinical score to help determine the risk of pneumonia. See Table 2 for a clinical score combined with CRP (in this study the threshold used was >30mg/l) 5
5. How to interpret the test The relevant NICE guidelines state: For people presenting with symptoms of lower respiratory tract infection in primary care, consider a point of care C-reactive protein test if after clinical assessment a diagnosis of pneumonia has not been made and it is not clear whether antibiotics should be prescribed. Use the results of the C-reactive protein test to guide antibiotic prescribing in people without a clinical diagnosis of pneumonia as follows: Do not routinely offer antibiotic therapy if the C-reactive protein concentration is less than 20 mg/litre. Consider a delayed antibiotic prescription (a prescription for use at a later date if symptoms worsen) if the C-reactive protein concentration is between 20 mg/litre and 100 mg/litre. Offer antibiotic therapy if the C-reactive protein concentration is greater than 100 mg/litre. THE TEST IS NOT A SUBSTITUTE FOR CLINICAL EXAMINATION AND THE APPLICATION OF CLINICAL SKILLS. The cut-off points are provided as a guide but the risk of pneumonia is higher with higher values of CRP. So a clinician may decide a different course of action for a low risk individual with a CRP of 21 in whom a delayed prescription may be appropriate compared to a high risk with a CRP of 90 in whom a short delay or clinical review may be indicated. Practices are required to record basic details of participant for future audit under this LIS a data sheet/emisweb Template will be provided for this purpose, no identifiable patient details will be recorded. Ensure that all healthcare professionals who are involved in administering the LIS have: Referred to the clinical guidance available; and The necessary experience, skills and training 6
6. Processing Procedure All blood samples should be processed immediately. Samples falling outside of this time frame should be discarded. 7. Maintenance More details can be found see link Cleaning the instrument The QuikRead go instrument has been designed to be as user-friendly as possible with no need for regular maintenance. For any repair requirement, contact your local supplier. Periodically clean the exterior of the instrument using a lint-free cloth dampened with water. Pay special attention to cleaning the display. Take care that no liquid runs onto the edges of the display, the measurement well or the connectors. Changing the clock battery The instrument has a battery which gives power to the internal clock. If the clock battery charge is empty a warning is displayed. The clock battery can be replaced with a same type of battery (type CR 2032 3V). Instrument calibration The instrument is factory calibrated. Proper functioning of the instrument is checked by the selfcheck procedure during every measurement. In case of malfunction, an error message is displayed. The calibration data defining the overall assay curve or cut-off value for each test is encoded on the cuvette label. This information is transferred automatically to the instrument during every measurement. 7 If necessary, a mild detergent may be used. Do not use organic solvents or corrosive substances. Spillage of potentially infectious material should be wiped off immediately with absorbent paper tissue and the contaminated areas swabbed with a standard disinfectant or 70% ethyl alcohol.
Materials used to clean spills, including gloves, should be disposed of as biohazardous waste. Software update New software can be uploaded to the instrument with a USB storage. Follow the instructions on the screen. Ask your local supplier for more information. 1. Turn off the instrument (if on). 2. Unplug the power supply cable. 3. Place the instrument onto its side on a table. 4. Open the accumulator unit cover. 5. If an accumulator unit is in place disconnect the accumulator connector from the accumulator unit and remove the accumulator unit. 6. Take the clock battery out of the battery holder. 7. Place new clock battery (type CR 2032 3V) into the battery holder text side down. 8. If an accumulator unit is used, attach the accumulator connector to the accumulator unit and press the accumulator unit into place and ensure that it is placed properly. Close the accumulator unit cover. 9. Turn the instrument back to a standing position and plug the power supply cable. 10. Start the instrument by pressing the Power button 11. Adjust the date and time (Settings Personal Settings Measurement flow Maintenance Date and Time) 1 0 8
8. Quality Control Procedure Regular use of QuikRead CRP Control (Cat. No. 68296) and/or QuikRead go CRP Control High (Cat. No. 137071) is recommended. QuikRead CRP Controls: QuickRead CRP Control and QuikRead go CRP Control High are ready-to-use. The control value has been determined for the QuikRead go instrument with the same instructions for use as for plasma/serum samples. The sample volume is 20 microlitres. If you want to use sample volume 12 microlitres, you have to change the setting of QuikRead go instrument. See Instrument manual: Setting Measurement flow Test parameters. Other commercially available CRP controls: Handle and use according to the instuctions for each control substance. Acceptable limits for the control must be defined with precision results gained with the QuikRead go instrument. The blanking process might not succeed if you use a control that contains artificial red blood cells because they might not haemolyse normally. More details can be found see link 9. Results A note of the CRP result must be entered in the patient s notes (EMIS Read code 44CC) 10. Sources of error More details can be found see link Error messages and Unexpected high/low results More details can be found see link 9
11. Disposal Disposal of all samples and other test materials should follow official regulations. All patient samples, used cuvettes, capillaries and plungers should be handled and disposed of as potentially infectious material. The plastic, cardboard and paper parts are separately recyclable. The aluminium tubes holding the reagent caps and the aluminium lids of the cuvettes are to be disposed of as recyclable metal. The foil covering the cuvetter rack is nonrecyclable and should be disposed of as general waste. When used in accordance with Good Laboratory Practice, good occupational hygiene and instructions for use, the reagents supplied should not present a hazard to health. More details can be found see link 10
Appendix 1. Links to Additional Training Materials Link to video training (online) Link to Orion Diagnostica online training for CRP testing Link to PDF instructions on collecting blood sample via skin prick testing 11