The result “<15 IU/mL, Detected” means that HCV RNA is detected, although at a level (<15 IU/mL) that is too low to be quantified. This result could indicate current active HCV infection if consistent with other clinical and laboratory data. NOTE: If this test is being performed for HCV diagnosis, then this <15 IU/mL Detected result should be confirmed using a second sample from the patient.
In contrast, the result “<15 IU/mL, Not Detected” means that HCV RNA is not detected and there is no evidence of current active infection.
Quest Diagnostics measures HCV RNA viral load with the Roche cobas® HCV methodology. This is a quantitative real-time PCR assay with a lower limit of quantification (LOQ) of 15 IU/mL; the limit of detection (LOD) is slightly lower, at 10 IU/mL to 13 IU/mL. If the viral load is just at or above this LOD, but less than 15 IU/mL, the assay can determine that HCV RNA is present but cannot provide a reliable quantitative result. In such cases, the qualitative result of “<15 IU/mL, Detected” is provided.