Effective December 6, 2021, Spectrum Health Reference Laboratory (SHRL) Coagulation department will go live with a new lot of Prothrombin Time (Protime/PT) reagents. The reference range for the PT will be adjusted to reflect this reagent lot change and align with our Regional Laboratories. The new reference range will be 9.5 – 12.0 seconds. There will be no change to the INR ranges.
| Test | Current Reference Range | New Reference Range |
| Prothrombin Time (PT) | 9.7 – 12.6 seconds | 9.5 – 12.0 seconds |
On Tuesday October 26, 2021, a new lot of aPTT reagent will go live for the Spectrum Health Laboratory Information System starting at 10:00 AM.
• The aPTT therapeutic range for ADULT patients on continuous heparin infusions will be updated to reflect the new reagents. The therapeutic range, for most indications, will be changed from 37 to 52 seconds to a new range of 42 to 57 seconds. UFH anti-Xa therapeutic ranges will remain unchanged (0.3 to 0.7 units/mL). All ADULT nomograms will be adjusted to reflect the new therapeutic ranges.
• For PEDIATRIC patients, aPTT nomograms will no longer be used in this population. Only the unfractionated heparin (UFH) anti-Xa nomograms will remain for PEDIATRIC patients, again with no changes made to their current UFH anti-Xa nomograms.
Beginning September 8, at approximately 2PM, Spectrum Health Laboratories will go live with their new lot of APTT reagent. This lot change triggered a new therapeutic curve resulting in new heparin nomograms for the system. The standard heparin therapeutic range will change from the current 45-65 seconds to a new range of 37-52 seconds based off the new curve. Reference ranges for the APTT assay will also be updated. Grand Rapids APTT reference range will be 21-27 seconds and the Regional Hospitals will be 21-31 seconds.
APTT specimens that are unable to reach an endpoint (no clot is detected), will reflex to the Unfractionated Heparin (UFH) (Test Code LAB3389) anti-Xa assay. To accommodate this change, UFH values have been added to heparin nomograms. The UFH anti-Xa assay is currently only performed in the Grand Rapids labs and valid only for unfractionated heparin. Any questions concerning these changes may be directed to the Spectrum Health Regional Laboratory Coagulation department at 616-267-2740.
Spectrum Health Regional Laboratory is adjusting the Microalbumin Analytic Measurement Range (AMR) in order to standardize within the Spectrum Health Hospital System and to align with our vendor’s (Roche Diagnostics) recommendations. The lower limit of the Microalbumin AMR will be changed from 0.50 to 1.20 mg/dL. Results below the AMR will now be reported as < 1.20 mg/dL. The upper limit will remain the same at 444.00 mg/dL.
As of October 1, 2018, the reference interval for Anti-Thyroid Peroxidase Antibody levels has been updated to 0.0 to 34.9 IU/mL from 0.0 to 8.9 IU/mL. This change is due in part to client feedback resulting in an audit of the existing range and leading to discovery that it had not been updated when the instrument had been changed.
We appreciate and welcome any and all client feedback; if you identify what may appear to be an incorrect reference interval, please notify us immediately using the “Contact Us” link above.
Effective immediately, the anion gap reference interval will be changed from 4-15 mmol/L to 9-18 mmol/L to reflect the system-wide standardization of electrolyte testing.
On May 1, 2017, Spectrum Health Regional Laboratory adjusted the reference range for C-Reactive Protein (CRP) from ≤10 mg/L to ≤5.0 mg/L.