HUMAN COSAVIRUS INFECTION IN HIV SUBJECTS WITH DIARRHOEA: PERSISTENT DETECTION ASSOCIATED WITH FATAL OUTCOME

Human cosavirus (HCoSV) is a new member of the Picornaviridae family, geographically widespread among humans. It has been suggested as a causative agent of acute gastroenteritis, but its pathogenicity is not currently certain. In HIV-infected subjects, diarrhoea is one of the most frequent gastrointestinal manifestations, whose aetiology remains often unexplained.

To identify the cause of viral diarrhoea among HIV infected patients by molecular assays.

A total of 143 stool samples from HIV subjects with and without diarrhoea, were screened for conventional enteric viruses (rotavirus, adenovirus, norovirus and astrovirus) by molecular assays. The presence of HCoSV genome was investigated by nested RT-PCR for the 5'UTR region. Positive samples were further characterized by sequencing and phylogenetic analysis.

Enteric viruses were more frequently found in diarrhoea cases (9/82) than controls (0/61) (p=0.007). HCoSV was detected in five (3.5%) of the subjects affected by diarrhoea. Phylogenetic analysis revealed the predominance of the HCoSV species D. One patient suffered a persistent cosavirus infection with a same strain and after eight months he had a fatal outcome. No other pathogens could be detected.

The results suggest a role of non-conventional enteric viruses, as HCoSV, as a potential opportunistic agent causing persistent infection and deterioration of the clinical conditions in HIV-infected patients. Screening procedures and monitoring including such viruses would be helpful in the clinical management of such patients.