Retrospective Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 14, 2018; 24(38): 4384-4392
Published online Oct 14, 2018. doi: 10.3748/wjg.v24.i38.4384
Practical fecal calprotectin cut-off value for Japanese patients with ulcerative colitis
Jun Urushikubo, Shunichi Yanai, Shotaro Nakamura, Keisuke Kawasaki, Risaburo Akasaka, Kunihiko Sato, Yosuke Toya, Kensuke Asakura, Takahiro Gonai, Tamotsu Sugai, Takayuki Matsumoto
Jun Urushikubo, Shunichi Yanai, Shotaro Nakamura, Keisuke Kawasaki, Risaburo Akasaka, Kunihiko Sato, Yosuke Toya, Kensuke Asakura, Takahiro Gonai, Takayuki Matsumoto, Division of Gastroenterology, Department of Internal Medicine, School of Medicine, Iwate Medical University, Morioka 020-8505, Japan
Tamotsu Sugai, Division of Molecular Diagnostic Pathology, Department of Pathology, School of Medicine, Iwate Medical University, Morioka 020-8505, Japan
Author contributions: All authors helped to perform the research; Urushikubo J manuscript writing, performing procedures and data analysis; Yanai S manuscript writing, drafting conception and design, performing experiments, and data analysis; Nakamura S contribution to writing the manuscript, drafting conception and design; Kawasaki K, Akasaka R, Sato K, Toya Y, Asakura K and Gonai T contribution to writing the manuscript; Sugai T reviewed the histological specimens and was responsible for the pathological diagnosis; Matsumoto T critically reviewed and revised the manuscript; all authors have read and approved the final version of the manuscripts.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Iwate Medical University Hospital.
Informed consent statement: Patients were not required to give informed consent as this is a retrospective study.
Conflict-of-interest statement: All authors declare no conflicts-of-interest related to this article.
Data sharing statement: No additional data are available.
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: Jun Urushikubo, MD, Doctor, Division of Gastroenterology, Department of Internal Medicine, School of Medicine, Iwate Medical University, Uchimaru 19-1, Morioka 020-8505, Japan. urujun50@gmail.com
Telephone: +81-19-6515111 Fax: +81-19-6526664
Received: July 10, 2018
Peer-review started: July 10, 2018
First decision: August 27, 2018
Revised: September 10, 2018
Accepted: October 5, 2018
Article in press: October 5, 2018
Published online: October 14, 2018
ARTICLE HIGHLIGHTS
Research background

Fecal calprotectin (FC) is a useful biomarker to assess disease activity in ulcerative colitis (UC). However, appropriate cut-off values of FC for the endoscopic and histologic remission has not yet been determined in Japanese patients with UC.

Research motivation

Calculating the FC cut-off value of the remissions will help to evaluate disease activity instead of invasive examination such as endoscopy.

Research objectives

To determine cut-off values of FC for endoscopic and histologic remission in Japanese patients with UC.

Research methods

We performed a retrospective study of Japanese patients with UC for measurement of FC that was measured by fluorescence enzyme immunoassay (FEI). We analyzed the relationship between FC and laboratory data, clinical activity, endoscopic score (Mayo endoscopic subscore: MES, Rachmilwitz endoscopic index: REI, ulcerative colitis endoscopic index of severity: UCEIS and histologic score (Matts grade, Riley’s histologic score).

Research results

In 131 patients, there was a statistically significant correlation between PMS and FC (P < 0.001). FC levels were significantly correlated with the MES (P < 0.001), REI (P < 0.001), UCEIS (P < 0.001), Riley’s histologic score (P = 0.006), and Matts grade (P < 0.001). Receiver-operating characteristic analyses identified the best cut-off value for the prediction of endoscopic remission as 288 μg/g, with an area under the curve (AUC) of 0.777 or 0.823, while that for histologic remission was 123 or 125 μg/g or 125 μg/g, with an AUC of 0.881 or 0.918.

Research conclusions

FC measured by FEI is considered a predictive biomarker for endoscopic and histologic remission in Japanese patients with UC.

Research perspectives

Our study showed that FC was useful biomarker for prediction of endoscopic and histologic activity. This research was a retrospective study, which is the maximum limitation. Further prospective studies are needed to confirm the reproducibility of the results of this research.