Siemens Free T3 Assay Kits Recalled for Positive Bias in Results
Siemens Healthcare Diagnostics is recalling Free T3 Assay kits due to a positive bias that may cause normal thyroid patients to appear abnormal.
What this means for you
Minor labeling or packaging issue, or a voluntary precautionary recall. Risk of harm is low but real — follow the manufacturer's instructions.
Our severity reasoning: The recall is classified as FDA Class II, which typically corresponds to a moderate severity score. The hazard involves a positive bias in test results that could lead to misdiagnosis, but the source does not report any hospitalizations, serious injuries, or deaths.
Plain-English summary
Siemens Healthcare Diagnostics is recalling 2,201 units of the T3F, Free T3 Assay (REF/Catalog Number LKF31, SMN 10381626) for use with IMMULITE/IMMULITE 1000 analyzers. The affected lots are 353 and 354. These kits are used for the quantitative measurement of Free T3 in serum to aid in the clinical assessment of thyroid status.
The recall was initiated after the company confirmed customer complaints regarding an increase in euthyroid patients (those with normal thyroid function) demonstrating values above the recommended normal range. A positive bias in quality control results was also observed, although values may remain within established ranges.
The affected kits were distributed worldwide, including nationwide in the United States and in numerous other countries. The source text does not specify instructions for consumers or healthcare providers regarding the disposal or return of the kits.
The recalled product
- Product
- T3F, Free T3 Assay, REF/Catalog Number LKF31, Siemens Material Number (SMN) 10381626; an IVD Immunoassay kit for use with the IMMULITE/IMMULITE 1000 Analyzers --- Shipping or unit package: 100, 200, 500 and 600 test kits --- Origin: UK Siemens Healthcare Diagnostics Products Lt
- Manufacturer
- Siemens Healthcare Diagnostics
- Affected units
- 2,201
Is your product affected?
Check your packaging against the codes below. If any of them match, the product is part of this recall.
Lot numbers (2)
- Lot Numbers 353
- 354
Distribution
Distributed nationwide across the United States.
Part of a larger recall action
This product is one of 2 recalled by Siemens Healthcare Diagnostics under a single FDA (Devices) recall action. The agency files each product separately, so the size of the action is not visible from this page alone.
See all 2 products in this recall →Related recalls
Same manufacturer · Siemens Healthcare Diagnostics
See all →- ModerateSiemens BC Thrombin Reagent Kit Recall for Unexpected Prolonged Results
FDA (Devices) · 2018-03-07
- ModerateSiemens IMMULITE 1000 Cortisol Assay Recalled for Positive Bias
FDA (Devices) · 2014-10-29
- ModerateSiemens Recalls ADVIA Centaur XP Immunoassay Systems Due to Data Error
FDA (Devices) · 2014-10-08
- ModerateSiemens Recalls ADVIA Centaur Immunoassay Systems Due to Data Error
FDA (Devices) · 2014-10-08
- ModerateSiemens ADVIA Centaur Immunoassay System Field Correction for Sample Rack Loading
FDA (Devices) · 2014-09-24
Same hazard · mis labeling
See all →- ModerateOlympus Recalls PowerSeal Sealer Due to Incorrect Outer Box Labeling
FDA (Devices) · 2026-09-02
- ModerateAVID Medical Recalls Halyard Total Joint Kits for Latex Labeling Deficiency
FDA (Devices) · 2026-09-02
- HighByron White A-L Complex Herbal Supplement Recalled for Undeclared Walnut
FDA (Food) · 2026-09-02
- ModerateMedline Trach Tube Kit Recalled for Component Labeling Discrepancy
FDA (Devices) · 2026-09-02
- SevereWhite Vein Advanced Alkaloids Chewable Tablets Recall for Excess Active Ingredient
FDA (Food) · 2026-09-02