Hepatitis C Point-of-Care Tests Are Highly Accurate

Point-of-care tests (POCTs) for the diagnosis of hepatitis C (HCV) have a high level of accuracy and may help increase screening rates for this disease.

Convenient, quality-assured, antibody-based rapid diagnostic tests (RDTs) and POCTs could facilitate preliminary screening, although they cannot differentiate between acute and chronic infections and their rapid turnaround time limits loss to follow-up and facilitates early associations.

Although both diagnostic test types are rapid, RDTs require special equipment, such as centrifuges and refrigerators, whereas POCTs eliminate the need for electricity and are more robust at high temperatures, thus offering additional opportunities to expand screening. A meta-analysis carried out by scientists at McGill University Health Center (Montreal, QC, Canada) reviewed 19 studies conducted between 1992 and 2012 that screened for HCV in adults. All the studies had evaluated the diagnostic accuracy of POCTs and RDTs that screen for HCV in oral fluid, whole blood, serum, or plasma.

The investigators found that POCTs had the highest sensitivity for whole blood at 98.9% and serum or plasma also at 98.9%. The RDTs of serum or plasma had the next-highest sensitivity of 98.4%, followed by POCTs of oral fluid at 97.1%.

Specificity of POCTs of whole blood and serum or plasma was also high, at 99.5% and 99.7%, respectively. The specificity of RDTs of serum or plasma followed, at 98.6%, and then the specificity of POCTs of oral fluid, at 98.2%.

The authors notes that because the tests evaluated in this meta-analysis detected antibodies to HCV, these POCTs could not differentiate between acute and chronic infections and could not detect infection within three months of exposure. Cases with possible false negative or false-positive results would require further screening, which may depend on available resources.

The authors concluded that given the convenience of POCTs and their rapid turnaround time, these results show great potential for expanded first-line screening for hepatitis C infection and demonstrate the utility of blood-based singleton POCTs and of multiplex POCTs designed to provide integrated HIV and HCV screening of at-risk populations. The study was published on October 16, 2012, in the journal Annals of Internal Medicine.

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