RT-PCR based analysis of cell culture negative stools samples from poliomyelitis suspected cases.

BACKGROUND

Routine diagnosis of acute flaccid paralysis (AFP) is still based on classical virological procedures. Several serotypes of enterovirus which possess the potential to cause neurological disorders are not easily isolated in the cell culture systems used for the AFP diagnosis.

OBJECTIVES

Our goal was to look into the presence of enterovirus genomes in fecal suspensions previously considered negative by cell culture procedures, using RT-PCR.

STUDY

DESIGN

One hundred and seventy-three fecal samples collected from AFP cases and contacts occurring in Brazil, Peru and Bolivia and tested negative regarding viral isolation, after inoculation in the cell lines RD and Hep2C, were analyzed by RT-PCR using a pair of primers which specifically detects enterovirus genome RNA's.

RESULTS

Twenty-six samples (15%) showed amplicons compatible with those observed for enterovirus RNA amplification. The identity of these amplicons were confirmed by nucleotide sequencing. By using RT-PCR directly in the fecal suspensions we were able to detect enterovirus RNA's in twenty-six additional samples. These samples would be considered as negative if only the standard cell-culture-based methodology had been utilized. No polioviruses were detected among the positive samples.