Reflex Testing

The following tests have a reflex test protocol defined. That is, based on the results of the test ordered by the physician, additional testing as defined here, may be performed, reported and billed. This list is reviewed annually. For more information on the individual tests that we offer, please refer to the list of Tests Available.

TEST	CPT CODE	PROTOCOL	REFLEXED TEST		CPT CODE
APCR	85307	If <2.0 If TCT is prolonged	Factor V Leiden (PCR) (Requires cells from whole blood) Hepzymeä treatment of sample		83891, 83896x4, 83908, 83912 85525
A low APCR ratio suggests the presence of FV Leiden. This should be confirmed by a specific DNA-based test. Heparin will prolong the clot time and cause spurious results. It must be removed before testing.
APTT	85730	If prolonged If TCT is prolonged		APTT 1:1 Mix Hepzymeä treatment of sample	85732 85525
Prolonged APTTs are repeated on a 1:1 mix with normal plasma to distinguish a factor deficiency from an inhibitor. Heparin will prolong the clot time and cause spurious results. It must be removed before testing.
DRVVT	85613	If ordered alone		PTT-LA Kaolin Clot Time	85730 85730
The International Society for Hemostasis and Thrombosis Scientific Subcommittee on Lupus Anticoagulants (LA) recommends the use of three distinct test systems for the diagnosis of LA. To increase the chance of detecting a LA we will also perform the PTT-LA and Kaolin Clot Time.
Factor VIII Inhibitor Factor IX Inhibitor	85335 85335	If ordered alone If ordered alone		Factor VIII activity Factor IX activity	85240 85250
The interpretation of Factor VIII or IX inhibitor results is complicated by the presence of significant levels of FVIII or IX activity, e.g. after specific replacement therapy. The appropriate factor assay will therefore be performed when inhibitor assays are ordered alone.
Kaolin Clot Time	85730	If ordered alone OR if prolonged If prolonged If TCT is prolonged		PTT-LA, DRVVT and Staclot-LA Kaolin Clot Time 1:1 mix Hepzymeä treatment of sample	85730 85613 85597 85732 85525
The International Society for Hemostasis and Thrombosis Scientific Subcommittee on Lupus Anticoagulants (LA) recommends the use of three distinct test systems for the diagnosis of LA. To increase the chance of detecting a LA we will also perform the PTT-LA and DRVVT. A prolonged Kaolin Clot Time is repeated on a 1:1 mix with normal plasma to distinguish a factor deficiency from an inhibitor. Heparin will prolong the clot time and cause spurious results – including potential misdiagnosis of a LA. It must be removed before testing.
PTT-LA	85730	If ordered alone or if prolonged If prolonged If TCT is prolonged		DRVVT, Staclot-LA, Kaolin Clot Time PTT-LA 1:1 Mix and Staclot-LA Hepzymeä treatment of sample	85613 85597 85730 85732 85597 85525
The International Society for Hemostasis and Thrombosis Subcommittee on Lupus Anticoagulants (LA) recommends the use of three distinct test systems for the diagnosis of LA. To increase the chance of detecting a LA we will also perform the DRVVT and Kaolin Clot Time. A prolonged PTT-LA is repeated on a 1:1 mix with normal plasma to distinguish a factor deficiency from an inhibitor. Heparin will prolong the clot time and cause spurious results – including potential misdiagnosis of a LA. It must be removed before testing.
PTT-LA 1:1 mix	85732	If not corrected		Staclot-LA	85597
Apparent inhibitory activity in the PTT-LA may indicate a LA. This can be confirmed by demonstrating correction of the clot time in the presence of hexagonal phase phospholipid, the basis of the Staclot-LA.
PFA-100 (CEPI)	85576	If abnormal		PFA-100 (CADP)	85576
Prolonged Closure Time in the CEPI test will be repeated with the CADP cartridge to distinguish an aspirin effect from a 'true' platelet defect.
Protein C Activity and Protein S Activity	85303 85306	If either <40% If TCT is prolonged		Factor VII Activity and Factor VIII Activity Hepzymeä treatment of sample	85230 85240 85525
The interpretation of low Protein C and S activity is aided by knowledge of the FVII activity since this has a similar half-life to Protein C. Thus, a similarly decreased FVII activity mitigates against a congenital deficiency of Protein C. Factor VII activity will be low in patients receiving coumadin and can aid interpretation of the Protein C and S results. High levels of Factor VIII can interfere with the Protein C and S assay systems, causing spuriously low levels.
Protein S Free Antigen	85306	If ordered alone		Protein S Total Antigen	85305
Interpretation of Protein S free antigen requires knowledge of Protein S total antigen level.
Protein S Total Antigen	85305	If ordered alone		Protein S Free Antigen	85306
Interpretation of Protein S total antigen requires knowledge of Protein S free antigen level.
Prothrombin Time	85610	If prolonged If TCT is prolonged		Prothrombin Time 1:1 Mix Hepzymeä treatment of sample	85611 85525
Prolonged PTs are repeated on a 1:1 mix with normal plasma to distinguish a factor deficiency from an inhibitor. Heparin will prolong the clot time and cause spurious results. It must be removed before testing.
Thrombin Time	85670	If prolonged		Reptilase Time	85635
Prolonged thrombin times may be due to heparin, fibrinogen defects or fibrin split products. The Reptilase time can help distinguish heparin from other causes of a prolonged thrombin time.
vWF Antigen	85246	If ordered alone		vWF Activity	85245
Some forms of von Willebrand Disease have normal, or near-normal, levels of vWF antigen. Knowledge of the vWF activity is important in both diagnosing and subtyping von Willebrand's Disease.