Ortho-Clinical Diagnostics and the FDA notified healthcare practitioners of a Class 1 recall of the company's hepatitis B surface antigen Confirmatory Kit because an unknown component in the diluting solution used to test blood and serum samples may produce "Not Confirmed" results for samples found to be positive with the initial test.

Such false-negative test results may prevent some patients infected with or carrying the hepatitis B virus from receiving necessary treatment. This is especially important for pregnant women whose tests show false-negative results. When their fetuses are born, they will be presumed negative, and not treated with the hepatitis B immunoglobulin and hepatitis B vaccine. Such infants have a 90% chance of progressing to chronic hepatitis B virus infection, resulting in possible liver transplantation or early death.

Previously reported results should also be reviewed, according to the company.