Quantitative evaluation of rotaviral antigenemia in children with acute rotaviral diarrhea.

BACKGROUND

Rotaviral antigen and RNA have recently been identified in the serum of patients with rotaviral gastroenteritis, but the roles they play in disease remains undetermined.

METHODS

Rotaviral antigen and RNA were quantified by enzyme-linked immunosorbant assay and by quantitative reverse-transcription polymerase chain reaction in stool and serum specimens from children with rotaviral diarrhea (n=102), children with nonrotaviral diarrhea (n=40), and nondiarrheal control children (n=30).

RESULTS

Rotaviral antigenemia was detected in 64%, 3%, and 0% of the children with rotaviral diarrhea, the children with nonrotaviral diarrhea, and the nondiarrheal control children, respectively. The level of rotaviral antigen in serum was approximately 2x10(2) -fold lower than that in stool, and a moderate correlation was observed between the 2 levels. Rotaviral RNA was detected in 93% of the antigen-positive serum specimens. The median number of RNA copies in serum was approximately 1 x 10(5) -fold lower than that in stool, and no correlation was observed between the 2 levels. Serum levels of both antigen and RNA were inversely associated with baseline titers of rotaviral serum immunoglobulin G (P<.01). Antigenemia was also associated with G1 serotype.

CONCLUSIONS

Rotaviral antigenemia and viremia were common in children with rotaviral diarrhea, but antigen and RNA levels in serum were substantially lower than those in stool. Antigenemia was associated with infection with G1 strains and with low baseline titers of rotaviral serum antibody.