Prospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 28, 2015; 21(44): 12667-12675
Published online Nov 28, 2015. doi: 10.3748/wjg.v21.i44.12667
Evaluation of a multiplex PCR assay for detection of cytomegalovirus in stool samples from patients with ulcerative colitis
Saifun Nahar, Atsushi Iraha, Akira Hokama, Ayako Uehara, Gretchen Parrott, Tetsuya Ohira, Masatoshi Kaida, Tetsu Kinjo, Takeshi Kinjo, Tetsuo Hirata, Nagisa Kinjo, Jiro Fujita
Saifun Nahar, Ayako Uehara, Gretchen Parrott, Tetsu Kinjo, Takeshi Kinjo, Tetsuo Hirata, Jiro Fujita, Department of Infectious, Respiratory, and Digestive Medicine, University of the Ryukyus, Okinawa 903-0215, Japan
Atsushi Iraha, Akira Hokama, Tetsuya Ohira, Masatoshi Kaida, Nagisa Kinjo, Department of Endoscopy, University of the Ryukyus, Okinawa 903-0215, Japan
Author contributions: Nahar S and Iraha A designed and performed the research; Nahar S drafted the manuscript; Hokama A and Parrott G reviewed the manuscript; Uehara A, Parrot G, Ohira T, Kaida M, Kinjo T, Kinjo T, Hirata T and Kinjo N provided technical support; and Hokama A and Fujita J supervised the project.
Institutional review board statement: All stool samples were taken after informed consent and ethical permission was obtained from patients participating in the study.
Conflict-of-interest statement: To the best of our knowledge, no conflict of interest exists.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Akira Hokama, MD, PhD, Clinical Professor, Department of Endoscopy, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0215, Japan. hokama-a@med.u-ryukyu.ac.jp
Telephone: +81-98-8951144 Fax: +81-98-8951414
Received: June 1, 2015
Peer-review started: June 3, 2015
First decision: July 10, 2015
Revised: August 3, 2015
Accepted: September 28, 2015
Article in press: September 30, 2015
Published online: November 28, 2015
Processing time: 178 Days and 21.7 Hours
Abstract

AIM: To evaluate a multiplex PCR assay for the detection of bacterial and viral enteropathogens in stool samples from patients with ulcerative colitis (UC).

METHODS: We prospectively analyzed 300 individuals, including immunocompetent patients, immunocompromised patients, and patients with UC. Stool samples were collected from the recto-sigmoid region of the colon by endoscopy. The samples were qualitatively analyzed for bacterial and viral enteropathogens with a multiplex PCR assay using a Seeplex® Kit. Additional clinical and laboratory data were collected from the medical records.

RESULTS: A multiplex PCR assay detected 397 pathogens (191 bacteria and 206 viruses) in 215 samples (71.7%). The most frequently detected bacteria were Escherichia coli H7, 85 (28.3%); followed by Aeromonas spp., 43 (14.3%); and Clostridium perfringens, 36 (12.0%) samples. The most prevalent viruses were Epstein-Barr virus (EBV), 90 (30.0%); followed by human herpes virus-6 (HHV-6), 53 (17.7%); and cytomegalovirus (CMV), 37 (12.3%) samples. The prevalence rate of CMV infection was significantly higher in the immunocompromised group than in the immunocompetent group (P < 0.01). CMV infection was more common in patients with UC (26/71; 36.6%) than in the immunocompetent patients excluding UC (6/188; 3.2%) (P < 0.01). CMV infection was more prevalent in UC active patients (25/58; 43.1%) than in UC inactive patients (1/13; 7.7%) (P < 0.05). Among 4 groups which defined by the UC activity and immunosuppressive drugs, the prevalence rate of CMV infection was highest in the UC active patients with immunosuppressive drugs (19/34; 55.8%). Epstein-Barr virus (EBV) infection was more common in the immunocompromised patients excluding UC (18/41; 43.9%) than in the immunocompetent patients excluding UC (47/188; 25.0%) (P < 0.05). The simultaneous presence of CMV and EBV and/or HHV6 in UC active patients (14/58; 24.1%) was greater than in immunocompromised patients excluding UC (5/41; 12.2%) (P < 0.05).

CONCLUSION: The multiplex PCR assay that was used to analyze the stool samples in this study may serve as a non-invasive approach that can be used to exclude the possibility of CMV infection in patients with active UC who are treated with immunosuppressive therapy.

Keywords: Polymerase chain reaction; Ulcerative colitis; Cytomegalovirus; immunosuppressive drugs; Epstein-Barr virus

Core tip: Infection with cytomegalovirus (CMV) can cause exacerbation of ulcerative colitis (UC). Thus, early diagnosis of CMV infection is important. Although endoscopic biopsy is the best approach for the diagnosis of CMV infection, this procedure may be invasive for patients and damaging to the inflamed intestine. Our prospective study on the use of the qualitative multiplex PCR assay in stool samples revealed that CMV infection is significantly more prevalent in UC active patients with immunosuppressive drugs. The multiplex PCR assay for stool samples may prove useful, non-invasive method to exclude the presence of CMV infection in patients with active UC who are treated with immunosuppressive drugs.