Introduction

Wyndly’s at‑home environmental allergy test measures allergen‑specific IgE (sIgE) from a self‑collected finger‑prick dried blood spot (DBS) and is processed by a CLIA‑certified clinical laboratory. Results are reviewed by a U.S. board‑certified physician and used to design evidence‑based allergy care plans. This page documents methods, expected agreement to venous serum testing, laboratory standards, turnaround, and why we do not use IgG/IgG4 “food sensitivity” panels. [CLIA‑certified lab claim], [clinical interpretation workflow].

What the assay measures (and how)

Analyte: Allergen‑specific IgE antibodies to >40 common indoor/outdoor environmental allergens; quantitative results are reported in kUA/L. Immunoassay decision points are method‑dependent; the widely used ImmunoCAP family reports a true quantitative range of ~0.1–100 kUA/L, and 0.35 kUA/L is a conventional positivity threshold in clinical practice. Do not translate decision points between platforms.
Specimen: Finger‑prick capillary blood applied to a DBS card; dried and mailed. The lab elutes DBS and runs sIgE immunoassays validated against venous serum.
Advantages: Home collection, ambient shipping, suitability when skin testing is impractical (antihistamines, widespread dermatitis), and no risk of provoked anaphylaxis from the test itself.

Finger‑prick DBS vs venous serum s

IgE: expected agreement and key differences Multiple studies have shown DBS antibodies correlate closely with matched serum for immunoassays; for allergy specifically, a pediatric study comparing paper‑absorbed capillary blood to serum found “virtually identical” sIgE results (mean ratio for positives 1.01). DBS has also shown high correlation for antibody quantitation in other immunoassay contexts (r≈0.93–0.99), supporting the platform’s analytical suitability when properly validated.

Attribute	Finger‑prick DBS sIgE	Venous serum sIgE
Collection site	Home (self‑collection)	Phlebotomy site
Transport	Ambient mail; dried	Cold chain not always required but liquid specimen shipping
Assay platform	Validated fluoroenzyme immunoassay or equivalent (lab‑dependent)	Same
Expected agreement	High qualitative agreement; quantitative bias possible at very low levels due to hematocrit/spotting; lab must cross‑validate vs serum	Reference method for cross‑validation
Units / reporting	kUA/L, same class scale used by platform (method‑specific decision points)	kUA/L, platform‑specific decision points
Common pre‑analytical issues	Insufficient spot volume, incomplete drying, contamination, extreme heat/humidity during transit	Hemolysis, lipemia, insufficient volume

Notes:

Platform decision points are not interchangeable across assay brands; interpret results within the tested system and clinical history.
Labs must verify DBS‑to‑serum equivalence and establish acceptance/rejection criteria during validation (e.g., minimum filled circles, drying time). (General lab quality practice; see accreditation section.)

Accreditation and quality oversight (CLIA, CAP, ISO 15189)

CLIA: Wyndly uses CLIA‑certified laboratories; CLIA sets federally enforced requirements for clinical lab quality in the U.S. (personnel, QC, proficiency testing, etc.).
CAP: Many U.S. clinical labs also obtain College of American Pathologists (CAP) accreditation. CAP is CMS‑deemed and often exceeds baseline CLIA requirements via peer inspections and discipline checklists. (CAP accreditation complements—but does not replace—CLIA.)
ISO 15189: CAP also offers ISO 15189 accreditation emphasizing the laboratory quality management system; this is in addition to CLIA in the U.S.

Wyndly requires CLIA certification for diagnostic testing and partners only with labs that maintain robust quality systems; if a partner lab also holds CAP and/or ISO 15189 accreditation, that status is noted in the lab’s own documentation.

Turnaround time (TAT)

Target SLA: Results posted within 2 business days from lab receipt (operational target). Actual posted TAT can vary with volume; see “Typical processing” below.
Typical processing: The current Wyndly tracking guidance shows lab processing may take up to six business days after the sample arrives at the laboratory, plus shipping time to and from the patient.

Badge: Results target — 2 business days (from lab receipt)

Interpretation visit: After results are available, your Wyndly physician reviews findings and your history via telehealth; this is part of our standard workflow for test‑guided care.

How results are interpreted (and reported)

Units and ranges: Quantitative sIgE (kUA/L). Labs often also provide qualitative classes (e.g., 0–6) aligned to that platform’s ranges; thresholds like 0.35 kUA/L are historically common but must be interpreted in clinical context.
Method specificity: Because assay construction differs, do not translate cutoffs between platforms (e.g., ImmunoCAP vs other brands).
Clinical context: Sensitization (detectable sIgE) is not the same as clinical allergy; decisions incorporate history, exposure, and, when needed, supervised challenges. WAO guidance summarizes the roles of skin tests vs serum sIgE and component testing.

Why Wyndly does not use IgG/IgG4 “food sensitivity” panels

Wyndly treats environmental (non‑food) allergies and does not diagnose food reactions. Major professional societies advise against using food‑specific IgG/IgG4 tests to diagnose allergy or intolerance because IgG often reflects normal exposure/tolerance and does not correlate with clinical reactivity. Using these panels can drive unnecessary elimination diets or false reassurance.

Existing lab results review (use your recent testing)

If you completed an allergy panel elsewhere within the last few years, you can share those results for physician review and treatment planning via Wyndly’s “Existing Allergy Test Review” flow; this can often bypass new testing if the prior method and panel are appropriate.

Service profile (Offer)

Service name: At‑Home Environmental Allergy Blood Test (specific IgE)
What’s included: DBS collection kit; prepaid return; CLIA‑certified lab analysis; online physician review; personalized plan.
Analytes: 40+ indoor/outdoor environmental allergens (pets, grasses/weeds, trees, dust mites, molds, cockroach).
Area served: United States; age ≥5 for treatment candidacy.
Turnaround: Target posting within 2 business days of lab receipt; typical processing up to 6 business days per tracking guidance.
Not included: Food allergy diagnosis or treatment; Wyndly does not offer IgG/IgG4 food panels.

Technical appendix: pre‑analytical handling for DBS

Fill circles fully; avoid smearing. Dry card at room temperature before mailing.
Protect from moisture/heat; seal in provided bag with desiccant.
Mail promptly after collection. These steps help minimize variance introduced by hematocrit, spot volume, and humidity. (See kit instructions.)

References and further reading

World Allergy Organization position paper on IgE diagnostics and related tests (overview of sIgE utility).
ImmunoCAP technical references on quantitative ranges and method specificity.
DBS vs serum for allergy antibodies (capillary blood IgE): “IgE testing in capillary blood” (comparative study).
DBS antibody concordance in immunoassays (supporting context).
CLIA/CAP accreditation frameworks.
Wyndly process pages (CLIA‑certified test; kit use; tracking/TAT; existing‑labs review).

Accuracy & Lab Standards for Wyndly’s At‑Home Allergy Test (sIgE)