RT-PCR Increases Sensitivity To Detect Cytomegalovirus in Paraffin-Embedded, Formalin-Fixed Tissue of Gastrointestinal Biopsies
Morgan H McCoy, Kristin Post, Joyashree D Sen, Hsim Y Chang, Zijin Zhao, Jingmei Lin. Indiana University School of Medicine, Indianapolis, IN
Background: Cytomegalovirus (CMV) infections lead to a variety of active disease manifestations and have been described in all age groups, especially in immunosuppressed patients such as those with HIV/AIDS, recipients of solid organ or hematopoietic transplants and those receiving chemotherapy. Diagnosis of CMV often relies on histopathologic examination on hematoxylin and eosin (H&E) stained sections for the identification of classic viral inclusions along with the aid of immunohistochemistry (IHC) or in-situ hybridization. However, sensitivity in diagnosing CMV infection by non-classic appearing inclusions or atypical IHC staining patterns remains an ongoing concern for pathologists.
Design: We report the use of real time polymerase chain reaction (RT-PCR) on nucleic acid extracted from paraffin-embedded, formalin-fixed tissue of gastrointestinal (GI) biopsies (n=84) from cases of CMV infection diagnosed by H&E or IHC.
Results: Of the 84 biopsies diagnosed as positive for CMV infection, 78 (92.9% sensitivity) tested positive by RT-PCR. Of the accessions these biopsies comprised, 26 cases had additional biopsies (N=40) taken either during the same procedure or previous procedures, some taken just days prior, which were diagnosed as negative for CMV infection by H&E or IHC. Interestingly, 25 biopsies (62.5%), which were diagnosed as negative previously, tested positive for CMV by RT-PCR with appropriate controls.
Conclusions: In summary, we demonstrate that RT-PCR is a sensitive and rapid molecular tool that may be employed on small GI biopsies to aid in the diagnosis of CMV infection.
Monday, March 4, 2013 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 107, Monday Morning