Polymerase chain reaction and the diagnosis of viral gastrointestinal disease due to cytomegalovirus, herpes simplex virus and adenovirus.

摘要

Polymerase chain reaction (PCR) and other molecular amplification methods provide a rapid and highly sensitive diagnosis. Thus some virology laboratories have eliminated cultures and offer only molecular methods. Since gastrointestinal (GI) biopsies yield usually one of three viruses by culture, cytomegalovirus (CMV), herpes simplex virus (HSV), or adenovirus, we considered implementing a PCR panel for these viruses instead of culture. To validate this strategy, we retrospectively analyzed 42 sequential GI biopsy samples from 31 patients submitted to the clinical laboratory for culture. Tissue was frozen at -70 癈 for up to 2 months until tested. Samples were extracted using the Nuclisens EasyMag (bioMerieux, Durham, NC) and tested in duplicate using real-time TaqMan PCR. Since cross-contamination is a concern, all samples with Ct values >38 in our laboratory are re-extracted and PCR is repeated in duplicate. Pathology, confirmed by immunostain, was considered the gold standard. Culture or PCR positives with negative pathology were considered of clinical significance if (1) the disease was compatible and no alternative diagnosis was made; or (2) other positive samples and/or the subsequent clinical course confirmed a viral etiology.