Concordance of a Capillary Blood Collection Device for Immune Surveillance in Pediatric Sepsis

Monday, March 23, 2026

9:00 AM - 10:00 AM Central Time

Location: Connections Central - RST 14

EC

Erin Carlton, MD, MSc

University of Michigan CS Mott Children's Hospital

Disclosure(s): No relevant financial relationship(s) to disclose.
LY

Lauren Yoder, BS

Research Coordinator
Univerity of Michigan

Disclosure information not submitted.
RC

Rebecca Clifford, BSN, RN

Pediatric Critical Care Medicine Research Coordinator
Nemours

Disclosure information not submitted.
JL

Jenna LaPira, M.S.

Research coordinator
Nemours Delaware

Disclosure information not submitted.
AF

Amanda Foxx, M.S., ASSP

Biological Safety & Environmental Health Coordinator Assistant Chemical Hygiene Officer
Nemours Children's Hospital

Disclosure information not submitted.
LG

Lisa Glazewski, MS

Research Lab Manager
Nemours Children's Hospital

Disclosure information not submitted.
SF

Sumera Farooqi, BS

Lab Manager
Nemours Children's Hospital

Disclosure information not submitted.
MC

Marian Cabrera-Ayala, BS

Research Assistant
Nemours Children's Hospital

Disclosure information not submitted.
SB

Sonali Barwe, PhD

Sr Research Scientist
Nemours Children's Hospital

Disclosure information not submitted.
Hallie Prescott, MD, MSc, FACP

University of Michigan, Michigan

Disclosure information not submitted.
Scott L. Weiss, MD, FCCM

Nemours Childrens Hospital
Sidney Kimmel Medical Center at Thomas Jefferson University, Pennsylvania

Disclosure information not submitted.

Introduction: Children who survive sepsis are frequently readmitted for new infections, suggesting immune dysregulation persists after hospital discharge. Impracticalities of phlebotomy post-discharge are a barrier to studying post-sepsis immune recovery. While capillary blood collection devices offer at-home blood testing, accuracy of immune assays using these devices is unknown. We hypothesized that capillary blood collection would have high concordance to traditional phlebotomy for measuring immune cell subsets and function.

Methods: We performed an observational study of children < 18 years treated for sepsis in two PICUs from January-June 2025. Paired blood samples were collected via phlebotomy (0.5 mL EDTA and 1 mL heparin) and the Tasso+ capillary blood collection device (0.5 mL EDTA). EDTA samples (standard and Tasso+) were kept at room temperature and shipped overnight to a core lab to measure lymphocyte profiles via flow cytometry: T-helper and T-cytotoxic subsets (naïve, effector, central memory, effector memory, and stem cell memory cells) and Treg cells. Ex vivo lipopolysaccharide (LPS)-stimulated whole blood TNFα was processed immediately (locally) using a standard protocol from the phlebotomy heparin tube and was processed from the Tasso+ EDTA tube after shipment to the core lab. Resulting supernatants after LPS stimulation were frozen at -80ºC and batch analyzed via ELISA. Concordance between paired samples (phlebotomy vs Tasso+) was compared using Pearson’s rho test.

Results: Nine patients were enrolled with median age 13 (IQR 7-16) years and median PELOD-2 score 5 (IQR 3-6). Across T-helper subsets, the median correlation between phlebotomy and Tasso+ blood collection was 0.84 (range 0.53-0.97; p-value range 0.0001-0.14; all significant except effector cells). Across T-cytotoxic subsets, the median correlation was 0.93 (range 0.77-0.97; p-value range 0.0001-0.02). Correlation for Treg was 0.86 (p=0.003). Correlation for LPS-stimulated TNFα was -0.57 (p=0.18).

Conclusions: Capillary blood collection yielded high concordance to standard phlebotomy for quantification of T-lymphocyte subsets but not for immune function via LPS-stimulated TNFα. At-home blood collection may help to better understand changes in immune cell subsets after sepsis but is limited for quantifying immune cell function.