Laboratory Updates from Mayo Medical Laboratories

Laboratory Updates from Mayo Medical Laboratories

Test code 550 Coagulation Consultation, Thrombosis/Hypercoagulability is now obsolete and has been replaced by new test code 83093, Thrombophilia Profile.

This profile contains the following tests:

• Prothrombin Time (PT)

• Activated Partial Thromboplastin Time (aPTT)

• Dilute Russells Viper Venom Time

• Thrombin Time

• Fibrinogen

• D-Dimer

• Soluble Fibrin Monomer

• Antithrombin III

• Protein C Activity

• Protein S Activity

• Prothrombin G20210A Mutation

• Special Coagulation Interpretation

• Activated Protein Resistance V

Effective February 1, Test code 81958 HIV-1 RNA Quantification, will be performed using the FDA-approved Cobas AmpliPrep/Cobas TaqMan HIV-1 Test, version 2.0. Due to the increased sensitivity of this updated real-time PCR assay, patients with previously low or undetectable HIV-1 viral load may show increased or detectable viral load with this assay. However, the clinical implications of a viral load <50 copies/ml remain unclear.

For the purpose of patient monitoring, the U.S. Department of Health & Human Services Panel on Antiretroviral Guidelines for Adults and Adolescents, defines virologic failure as a confirmed viral load of >200 copies/mL. This eliminates most cases of viremia resulting from isolated blips or assay variability. Confirmed viral load rebound (ie, >200 copies/mL) on two separate tests obtained at least two to four weeks apart should prompt a careful evaluation of patients tolerance of current drug therapy, drug-drug interactions and patient adherence.