Many primary care providers have reached out seeking guidance about how to conduct point of care (POC) testing in their offices. Current data indicate that most rapid point of care tests have decreased sensitivity compared to hospital/laboratory-based PCR assays.
Although POC tests may be useful in some circumstances, a negative POC test in a child with a high pretest probability (such as known exposure or consistent symptoms) should be verified by a more sensitive laboratory-based PCR assay.
Get more information about POC testing from the CDC.
How to collect a nasopharyngeal swab specimen in your office and send it to our lab
For community providers who are interested in collecting patients’ nasopharyngeal swab sample and couriering it to Children’s Colorado for processing, please refer to the questions and answers below about how to collect a good nasopharyngeal swab.
All testing must be accompanied by a lab order with matching patient details (spelling of names and DOB) between specimen and paperwork or testing will be held or discarded.
Provider office specimen collection details
The below table is in order of preferred specimen type. All specimens are required to have parafilm around the top of the specimen to ensure they do not leak and should be placed in a biohazard bag with the paperwork in the outside pocket.
Specimen type: |
Transport details: |
Temperature: |
Nasopharyngeal (NP) swab |
Viral, UTM, amies or sterile saline |
Refrigerator pack |
Nasal wash |
Saline |
Nasal mid-turbinate (NMT) swab |
Viral, UTM, amies or sterile saline |
Anterior nares (nasal swab) |
Viral, UTM, amies or sterile saline |
Sputum |
Saline |
Tracheal aspirate |
Saline |
Bronchoalveolar lavage (BAL) |
Saline |
- At-home collections are not permissible for SARS-CoV-2 Testing
- Any specimen types beside NP swab, Nasal Wash, Tracheal Aspirate, or BAL could have decreased sensitivity
Sending specimens to the Children’s Colorado laboratory
- Please utilize a courier service to have specimens delivered to:
- Children’s Hospital Colorado
Attn: Clinical Lab – Microbiology
13123 E. 16th Ave, RM B0200
Aurora CO 80045
- Couriers will enter our facility through our dock and be screened daily before being allowed to come into the lab.
- If you do not have a current courier, we recommend reaching out to Action Stat Logistics to set up a courier account with them.
Ordering information and requirements
- In Epic/PedsConnect/ChildrensConnect:
Testing requested: |
Lab order to use/indicate: |
SARS-CoV-2 PCR |
LAB9100 |
Respiratory Pathogen Panel (RPP) |
LAB5595 |
- RPP does not automatically include SARS, request both labs if you want both to be run
- If you do not have access to Epic/PedsConnect/ChildrensConnect please reach out to LabClientServices@childrenscolorado.org for a lab requisition.
- We are required to report all patient demographics (including address and phone number); please be sure to include a face or demographic sheet with all specimens. This is a requirement.
- A diagnosis code is a requirement, please provide the code and not description with all submissions.
- Please be sure to make sure all patient information is legible and if the spelling of the patient name does not match between the specimen and the paperwork the specimen could be rejected or resulting could be delayed.
Children’s Colorado mobile clinic collection details
All patients need an appointment and order placed before arriving at our mobile sites. Wait times for appointments are long but we are doing the best we can.
What testing platforms are available at Children’s Colorado for SARS-CoV-2 detection?
- All the testing platforms used at Children’s Colorado are polymerase chain reaction (PCR) based assays and detect viral RNA.
- At Children’s Colorado, we currently are running three primary different platforms for SARS-CoV-2 PCR testing:
- CDC SARS-CoV-2 PCR assay – detects 2 targets on N gene.
- Simplexa/DiaSorin COVID-19 Direct – detects ORF1ab and S genes.
- Abbot m2000 Real-Time SARS-CoV-2 – detects RdRp and N genes.
- All three platforms utilize two different gene targets, which provide optimal sensitivity and minimizes potential for missing detection of virus due to potential new mutations.
Turnaround times (TAT) and resulting process:
- All platforms have a 24-hour TAT from the time the specimen arrives in our laboratory at Anschutz Medical Campus (there might be a slight delay for other locations or during periods of increased demand).
- If you are wanting us to collect a patient for an upcoming procedure, please make sure to plan accordingly to manage the result TAT. We recommend collection to be 48 hours in advance.
- Providers with Epic/PedsConnect/ChildrensConnect should check their inbox or the patient’s chart to see results.
- Providers without Epic/PedsConnect/ChildrensConnect and have submitted a paper requisition for orders will receive results via faxing [make sure fax number is correct on lab order].
- If it has been more than 24 hours and the patient's chart does not have a result or a fax has not been received, please email LabClientServices@childrenscolorado.org or call 720-777-6711.
- If emailing, include patient's first and last name, DOB and the fax number and a result or update will be sent to you within two hours during business hours (Monday through Friday from 8 a.m. to 4 p.m.)
- We highly recommend encouraging patients to sign up for MyChart, negative results will be uploaded in the system after completion and positive results will be uploaded after 24 hours.
- Our lab is not calling positives to external providers or their patients, the provider office will need to notify their patients.
Can I request a specific testing platform when placing an order?
- No. To optimize workflow processes in the laboratory and due to the equivalency between assays, samples will be run when received on the next available platform. Our goal in the Microbiology Laboratory is to provide optimum results in the least amount of time that supports isolation and medical decisions for the patient.
What is the sensitivity and specificity of our SARS-CoV-2 assays?
- All currently available assays for detection of SARS-CoV-2 RNA have been granted FDA EUA (Emergency Use Authorization). Because of this, no clinical trials have been conducted and there is no available data regarding the overall clinical sensitivity and specificity of these assays. Additionally, currently there is no gold standard diagnostic test of comparison studies to determine sensitivity and specificity of individual assays. In lieu of definitive clinical sensitivity data, limit of detection data has been provided as a proxy measure. Similar to other viral detection methods, PCR has become the gold standard for detection of virus in respiratory, gastrointestinal, and sterile fluids.
- To assess overall performance, the manufacturers of all the assays we are using conducted studies using approximately 100 contrived samples (CDC and Abbott – used RNA spiked into samples) or comparator clinical sample (DiaSorin – utilized samples from 3 different sites in Italy). All 3 assays had 100% negative percent agreement and 100% positive percent agreement, which are terms that describe analytical sensitivity and specificity, respectively, when a new test is evaluated by a comparator assay that is not a diagnostic gold standard.
- The manufacturers of these assays also conducted studies to assess specificity by running samples that were known to be positive for the other six known human coronaviruses and a diverse panel of other common respiratory pathogens, and all three assays demonstrated no cross reactivity, thereby confirming excellent specificity.
- In addition to the manufacturer’s studies, we conducted our own internal verification studies, which demonstrated assay performance in accordance with the manufacturer’s claims.
What is the limit of detection for the testing platforms at Children’s Colorado?
- The limit of detection for our assays is in the range of 100 – 500 viral genomic RNA copies/mL, which is considered extremely low (meaning the assays can detect a very small amount of virus).
- For comparison, the limit of detection on the BioFire respiratory pathogen panel is in the range of 10 – 500 RNA or DNA copies/mL depending on the pathogen.
What do we know about SARS-CoV-2 viral load in clinical specimens?
- In one study of symptomatic adults with COVID-19, the mean viral load in nasal swabs from positive patients was 1.4 x 106 (1,400,000) copies/mL. Another study in symptomatic adults demonstrated viral loads in nasal swabs ranging from 1.5 x 104 to 1.5 x 107 copies/mL, depending on the day of illness.
- Viral loads are higher earlier in the course of the disease.
- Viral loads are highest in nasopharyngeal (NP) swab specimens.
- Some studies have suggested that adults with more severe disease tend to have higher viral loads.
- Patients with milder disease tend to have earlier viral clearance.
What is the risk of a “false negative” test result?
- All our assays have excellent performance characteristics. Provided that a sample contains virus in the amount greater than our limit of detection, the risk of a false negative is extremely low.
- Clinical false negatives are usually not a result of test performance. Reasons for clinical false negatives could include:
- Poor sample collection.
- Degradation of viral RNA during shipping or storage of samples (rare).
- Intermittent shedding of virus.
- Stage of infection – very early in the course of an infection (during the incubation period, likely prior to contagiousness), or late in the course of disease viral loads may be undetectable.
- Type of specimen – some studies have demonstrated that in patients with severe lower respiratory tract disease, upper respiratory tract specimens (NP swabs/nasal washes) may be negative. For these patients, a tracheal aspirate (TA) or bronchoalveolar lavage (BAL) should be considered for testing if the NP swab or nasal wash specimen is negative.
- Although only recommended in certain circumstances, the ability to detect the presence of virus in asymptomatic compared to symptomatic patients should be equivalent.
How will our patients be charged?
- We will bill your patient’s insurance directly so please provide a diagnosis code along with insurance information (i.e. payor, plan type, subscriber ID, subscriber DOB, etc.) for your patients.
- Please also provide us a good contact to reach out to if we have questions regarding the information we have been provided or if we have issues getting the insurance approved.
Who can we contact if we have questions?
- If looking for results please contact Lab Client Services at LabClientServices@childrenscolorado.org and include patients first and last name and a DOB, or during normal business hours (Mon. – Fri. 8a – 4p) you can call 720-777-6711.
- For details on sending specimens, billing or other inquiries please reach out to the Supervisor of Lab Client Services, Amber Rodriguez, at Amber.Rodriguez@childrenscolorado.org or 720-777-2723.
- Email will provide a quicker response, so please include a good phone number.
- Please remember that our teams our doing the absolute best that we can to manage a significant volume of specimens and maintain a 24-hour TAT. We ask that you be patient with our teams and utilize our Lab Client Services email for inquiries so that our lab techs can focus on testing.
References:
- Casto A, et al. “Comparative Performance of SARS-CoV-2 Detection Assays using Seven Different Primer/Probe Sets and One Assay Kit .” medRxiv, 2020.
- Kam K-Q, et al. “A Well Infant With Coronavirus Disease 2019 With High Viral Load.” CID, 2020.
- Kim J.Y. et al. “ Viral load kinetics of SARS CoV-2 infection in first two patients in Korea. J. Korean Med Sci., 2020.
- Liu Y, et al. “Viral Dynamics in Mild and Severe Cases of COVID-19.” Lancet Infectious Diseases, 2020.
- Pan Y, et al. “ Viral Load of SARS-CoV-2 in Clinical Specimens.” Lancet Infectious Diseases, 2020.
- Patel R, et al. “Report from the American Society for Microbiology COVID-19 International Summit, 23 March 2020: Value of Diagnostic Testing for SARS–CoV-2/COVID-19.” mBio, 2020.
- Theravajan I, et al. “Breadth of concomitant immune responses prior to patient recovery: a case report of non-severe COVID-19.” Nature, 2020.
- Wang W, et al. “Detection of SARS-CoV-2 in Different types of Clinical Specimens.” JAMA, 2020.
- Wolfel, R. “Virological assessment of hospitalized cases of coronavirus disease 2019.” medRxiv, 2020.
- Xi, H, et al. “Temporal Dynamics in Viral Shedding and Transmissibility of COVID-19.” medRxiv, 2020.
- Yang Y, et al. “Evaluating the Accuracy of Different Respiratory Specimens in the Laboratory Diagnosis and Monitoring the Viral Shedding of 2019-nCoV Infections.” medRxiv, 2020.
- Zou L, et al. “SARS-CoV-2 Viral Load in Upper Respiratory Specimens of Infected Patients.” NEJM, 2020.