Stable enterovirus 5' nontranslated region over a 7-year period in a patient with agammaglobulinemia and chronic infection.

Cerebrospinal fluid samples obtained 7 years apart from a patient with chronic meningoencephalitis and underlying agammaglobulinemia were examined to determine enteroviral genotypic variability. From each sample, amplicons spanning 496 nucleotides within the 5' nontranslated region were generated directly from the cerebrospinal fluid and analyzed. A consensus sequence derived from 3 clones of each amplicon revealed only 7 nucleotide changes over the 7-year period within the region studied. The observed 5' nontranslated region mutation rate in this patient ( approximately 0.2% per year) was significantly lower than mutation rates reported for the poliovirus genome.