Healthcare facilities have been faced with a variety of new challenges in delivering quality healthcare during the COVID-19 global pandemic. To minimize risk of potential exposures for patients and healthcare staff and to mitigate personal protection equipment (PPE) shortages, many healthcare systems are shifting in-person visits to virtual. The infrastructure required for successful virtual clinics is not trivial, including needing a system for obtaining necessary lab work. Pediatric solid organ transplant and diabetes clinic are prime examples of high-risk patient populations, needing frequent lab monitoring for immunosuppressant levels and organ function markers.

Seattle Children’s pediatric solid organ transplant program developed a remote collection service to monitor four immunosuppressants (cyclosporine, everolimus, sirolimus, and tacrolimus) and creatinine in dried blood spots (DBS) (1), to support families who did not live close to the hospital. This service involves coordination between nurse transplant coordinators and lab staff to prepare and mail packets to the family; the families need to be clinically stable and trained to collect quality dried spots. The program was modest, with <1/3 of eligible families choosing to participate consistently. When visits to the clinics were limited to clinically urgent appointments, all patients were transitioned to using remote collection for immunosuppressant monitoring. We observed an increase in DBS utilization more than 3x in the first 10 weeks of the pandemic.

In the spring of 2020, we were asked to create a similar program to support glycemic control monitoring for patients with type 1 diabetes. There is precedent for monitoring HbA1c in DBS from the literature. Using DBS as a tool in research settings allows sample collection and analysis without requiring an in-person visit. Many of these studies used high-throughput methods, such as ion exchange chromatography (2), although one specific study reported validating HbA1c in DBS by an immunoturbidimetric method that is similar to our in-house assay for whole blood HbA1c (3). We validated the assay as a lab-developed test on the Vitros 4600 and deployed it with partnership from the diabetes clinic staff (4). We measured the initial completion rate by calculating the number of samples received divided by orders placed. In the first two months, the completion rate was 53%. Since then, a subset of patients continues to use the service, even when given the choice of an in-person lab visit.

When considering implementing a remote collection program, there are great resources available for the analytical and clinical validation, including best practices from the European Bioanalysis Forum (5). Once a suitable method is developed and validated, the next step is partnering with the clinical service who will offer remote collection to their patients. Establishing processes for training families, creating and distributing collection supplies, and ordering and tracking systems requires innovation and collaboration. Setting up reliable logistics may not be as interesting as the assay development itself, however, once these initial hurdles have been overcome, the sky is the limit with advancing remote collections for laboratory testing. Populations with long-term care needs are best suited for these advancements, and next, we are considering hormone monitoring in DBS for patients with congenital adrenal hyperplasia. Stay tuned!


  1. Dickerson JA, Sinkey M, Jacot K, Stack J, Sadilkova K, Law YM, Jack RM.
    Tacrolimus and sirolimus in capillary dried blood spots allows for remote monitoring. Pediatr Transplant. 2015;19(1):101-6.

  2. Egier D.A., Keys J.L., Hall S.K., McQueen M.J.: Measurement of hemoglobin A1c from filter papers for population-based studies. Clin Chem 2011; 57: pp. 577-585.

  3. Jones T.G., Warber K.D., Roberts B.D.: Analysis of hemoglobin A1c from dried blood spot samples with the Tina-quantR II immunoturbidimetric method. J Diabetes Sci Technol 2010; 4: 244-249.

  4. Roberts A.J., Malik F., Pihoker C, Dickerson, J.A. Adapting to telemedicine in the COVID-19 era: Feasibility of dried blood spot testing for hemoglobin A1c. Diabetes Metab Syndr, 2021; 15(1): 433-437.

  5. Timmerman P., White S., Globig S., Ludtke Sl, Brunet L., Smeraglia J. EBF recommendation on the validation of bioanalytical methods for dried blood spots. Bioanalysis, 2011; 3(14):1567-1575.