BACKGROUND: The COVID-19 outbreak is now a pandemic disease reaching as much as 210 countries worldwide with more than 2.5 million infected people and nearly 200.000 deaths . Amplification of viral RNA by RT-PCR represents the gold standard for confirmation of infection, yet it showed false-negative rates as large as 15-20% which may jeopardize the effect of the restrictive measures taken by governments . We previously showed that several hematological parameters were significantly different between COVID-19 positive and negative patients . Among them aspartate aminotransferase and lactate dehydrogenase had predictive values as large as 90% . Thus a combination of RT-PCR and blood tests could reduce the false-negative rate of the genetic test .
METHODS: We retrospectively analyzed 24 patients showing multiple and inconsistent RT-PCR, test during their first hospitalization period, and compared the genetic tests results with their AST and LDH levels .
RESULTS: We showed that when considering the hematological parameters, the RT-PCR false-negative rates were reduced by almost 4-fold .
CONCLUSIONS: The study represents a preliminary work aiming at the development of strategies that, by combining RT-PCR tests with routine blood tests, will lower or even abolish the rate of RT-PCR false-negative results and thus will identify, with high accuracy, patients infected by COVID-19.