Yoshihiro Nakazato
Keio University
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Featured researches published by Yoshihiro Nakazato.
Digestion | 2016
Shinya Sugimoto; Makoto Naganuma; Hiroki Kiyohara; Mari Arai; Keiko Ono; Kiyoto Mori; Keiichiro Saigusa; Kosaku Nanki; Kozue Takeshita; Tatsuya Takeshita; Makoto Mutaguchi; Shinta Mizuno; Rieko Bessho; Yoshihiro Nakazato; Tadakazu Hisamatsu; Nagamu Inoue; Haruhiko Ogata; Yasushi Iwao; Takanori Kanai
Background/Aims: Chinese herbal medicine Qing-Dai (also known as indigo naturalis) has been used to treat various inflammatory conditions. However, not much has been studied about the use of oral Qing-Dai in the treatment for ulcerative colitis (UC) patients. Studies exploring alternative treatments for UC are of considerable interest. In this study, we aimed at prospectively evaluating the safety and efficacy of Qing-Dai for UC patients. Methods: The open-label, prospective pilot study was conducted at Keio University Hospital. A total of 20 patients with moderate UC activity were enrolled. Oral Qing-Dai in capsule form was taken twice a day (daily dose, 2 g) for 8 weeks. Results: At week 8, the rates of clinical response, clinical remission, and mucosal healing were 72, 33, and 61%, respectively. The clinical and endoscopic scores, CRP levels, and fecal occult blood results were also significantly improved. We observed 2 patients with mild liver dysfunction; 1 patient discontinued due to infectious colitis and 1 patient discontinued due to mild nausea. Conclusion: This is the first prospective study indicating that oral Qing-Dai is effective for inducing remission in patients with moderate UC activity and can be tolerated. Thus, Qing-Dai may be considered an alternative treatment for patients, although further investigation is warranted.
Digestive Endoscopy | 2016
Keiichiro Saigusa; Katsuyoshi Matsuoka; Shinya Sugimoto; Mari Arai; Hiroki Kiyohara; Kozue Takeshita; Shinta Mizuno; Kiyoto Mori; Kosaku Nanki; Tatsuya Takeshita; Yoshihiro Nakazato; Tomoharu Yajima; Makoto Naganuma; Tadakazu Hisamatsu; Haruhiko Ogata; Yasushi Iwao; Takanori Kanai
Ulcerative colitis (UC) is a chronic inflammatory bowel disease that is characterized by periods of remission and episodes of relapse. Mucosal healing is an emerging therapeutic target in UC and various scoring systems have been used. The UC endoscopic index of severity (UCEIS) is the only validated endoscopic index at present, with minimum interobserver variation. Correlation of UCEIS scores after treatment and clinical outcomes of UC has not been examined. In the present study, we aimed to evaluate the usefulness of UCEIS after treatment with infliximab.
Endoscopy | 2017
Yoshihiro Nakazato; Makoto Naganuma; Shinya Sugimoto; Rieko Bessho; Mari Arai; Hiroki Kiyohara; Keiko Ono; Kosaku Nanki; Makoto Mutaguchi; Shinta Mizuno; Taku Kobayashi; Naoki Hosoe; Masayuki Shimoda; Takayuki Abe; Nagamu Inoue; Haruhiko Ogata; Yasushi Iwao; Takanori Kanai
Background and study aim Endocytoscopy (ECS) is used in the in vivo microscopic inspection of microstructural mucosal features and enables endoscopists to assess the histological severity of ulcerative colitis (UC). The aim of this study was to assess histological healing in UC patients by using ECS. Patients and methods A total of 64 patients in clinical and endoscopic remission who underwent ECS were selected. The correlation between the ECS score and Geboes score at the rectum was evaluated in patients with a Mayo endoscopic score (MES) of 0. The diagnostic accuracy of the ECS score for histological remission (Geboes score ≤ 2) was also assessed. Results The ECS score ranged from 0 to 5 in patients with endoscopic remission on conventional white-light images (MES of 0). The agreement between histological remission regarding the ECS score and the Geboes score had a κ value of 0.72, and the ECS score showed high accuracy for histological remission, with a sensitivity of 0.77, a specificity of 0.97, and a diagnostic accuracy of 0.86. Conclusion ECS can be used to assess histological healing in patients with UC without the need for biopsy specimens.
Gastrointestinal Endoscopy | 2017
Shinya Sugimoto; Makoto Naganuma; Yasushi Iwao; Katsuyoshi Matsuoka; Masayuki Shimoda; Shuji Mikami; Shinta Mizuno; Yoshihiro Nakazato; Kosaku Nanki; Nagamu Inoue; Haruhiko Ogata; Takanori Kanai
BACKGROUND AND AIMS Recent advances in endoscopic equipment and diagnostic techniques have made possible the detection of early dysplasia in the inflamed mucosa of ulcerative colitis (UC). The SCENIC consensus statement recommends the use of unified terminology for the morphology of dysplasia. In this study, we investigated the endoscopic features of high-grade dysplasia (HGD) in a clinical setting. METHODS We retrospectively identified 62 patients with UC who were diagnosed with colitis-associated cancer or HGD between 1997 and 2015. A total of 39 lesions of HGD detected by targeted biopsy sampling in 31 patients were reviewed, and the endoscopic morphology was classified according to the SCENIC guidelines. RESULTS In total, 0 (0%), 6 (15.4%), 19 (48.7%), 12 (30.8%), and 2 (5.1%) lesions with HGD were classified as pedunculated, sessile, superficial elevated, flat, and depressed, respectively. Nearly 80% of the lesions were located in the rectum or sigmoid colon. All flat and depressed lesions were red in color. Typically, sessile/superficial elevated lesions accompanied a flat area (Is+IIb/IIa+IIb). Ulceration was observed in 2 depressed lesions (5.1%). Although the borders were indistinct in 21 lesions (53.8%) without the use of magnifying colonoscopy, all lesions could be distinguished from the surrounding mucosa using magnifying endoscopy. CONCLUSIONS This is the first study to classify the morphologic features of HGD using the SCENIC guidelines in a clinical setting. Based on our findings, endoscopists should recognize that HGD is frequently associated with a flat/superficial elevated area and red discoloration and should inspect particularly carefully in the rectum and sigmoid colon. The findings of chromoendoscopy and magnifying colonoscopy may also be useful in distinguishing lesions from the surrounding mucosa.
PLOS ONE | 2017
Tomohiro Fukuda; Makoto Naganuma; Shinya Sugimoto; Kosaku Nanki; Shinta Mizuno; Makoto Mutaguchi; Yoshihiro Nakazato; Nagamu Inoue; Haruhiko Ogata; Yasushi Iwao; Takanori Kanai
Background 5-Aminosalicylic acids (5-ASA) are effective for ulcerative colitis (UC) as a maintenance therapy. It is not clear when and how to reduce a dose of 5-ASA after inducing remission. We aimed to investigate the clinical characteristics and evaluate the risk factors of relapse for UC patients receiving 5-ASA. Methods The medical records of prospectively registered UC patients who received oral 5-ASA as maintenance therapy between January and December 31, 2014, were investigated. The patients’ clinical characteristics in a 2-year follow-up were compared between a relapse group and a remission group. Results Of 527 UC patients receiving only oral 5-ASA, 390 (74.0%) maintained remission and 137 (26.0%) relapsed during the follow-up period. Multivariable analysis indicated that a shorter duration of disease remission (p < 0.001, OR: 1.24, 95% CI: 1.12–1.38) was statistically significant for each comparison between the remission and relapse groups among all the patients. Risk factors for clinical relapse were a shorter duration of disease remission (p <0.001, OR: 1.17, 95% CI: 1.04–1.33) in the high-dose 5-ASA group and a shorter duration of disease remission (p = 0.003, OR: 1.45, 95% CI: 1.13–1.89) and a history of steroid use (p = 0.048, OR: 4.73, 95% CI: 1.01–22.2) in the low-dose group. Conclusions A dose reduction of 5-ASA might be cautiously selected in UC patients with a history of steroid use and a shorter duration of disease remission.
VideoGIE | 2018
Yoko Kubosawa; Toshihiro Nishizawa; Satoshi Kinoshita; Yoshihiro Nakazato; Toshio Uraoka
Colonic diverticula are caused by increased intracolonic pressure or by a weakened colonic wall. Most colonic diverticula consist of acquired pseudodiverticula and do not have a muscle layer. Therefore, there is a risk for perforation when EMR is used for polyps adjacent to diverticula. We report 2 cases of cold snare polypectomy for polyp adjacent to colonic diverticula (Video 1, available online at www.VideoGIE.org). Case 1: A 6-mm-diameter flat polyp was located in the ascending colon. This lesion was adjacent to a diverticulum (Fig. 1A). Narrow-band imaging (NBI) magnification showed type 2A of the Japanese NBI Expert Team (JNET) classification and indicated adenoma. We performed cold snare
Inflammatory Bowel Diseases | 2018
Tomohiro Fukuda; Makoto Naganuma; Shinya Sugimoto; Keiko Ono; Kosaku Nanki; Shinta Mizuno; Kayoko Kimura; Makoto Mutaguchi; Yoshihiro Nakazato; Kaoru Takabayashi; Nagamu Inoue; Haruhiko Ogata; Yasushi Iwao; Takanori Kanai
BACKGROUND Mucosal healing (MH) is proposed as a therapeutic target for ulcerative colitis (UC). Recent studies have indicated that the rate of clinical relapse in patients with a Mayo endoscopic score (MES) of 1 is higher than that of patients with an MES of 0. However, no study has yet investigated whether therapeutic intervention prevents clinical relapse in patients with an MES of 1. METHODS Patients with UC with an MES of 1 and partial Mayo score ≤2 were included in this study. All patients were followed from first colonoscopy (CS) until follow-up CS. Differences in the rate of clinical relapse (requiring additional treatment for UC) or endoscopic exacerbation (MES ≥2 and proximal extension) were compared between the therapeutic intervention (immediately after first CS) group and the nontherapeutic intervention group; risk factors for relapse were also assessed. RESULTS Among 1523 patients with UC who underwent CS between 2013 and 2016, 220 patients were included in this study. The rate of clinical relapse (P = 0.005) and endoscopic exacerbation (P = 0.11) in patients with therapeutic intervention was lower than that in patients without therapeutic intervention. Multivariable analysis indicated that absence of therapeutic intervention (P = 0.001 for clinical relapse, P = 0.050 for endoscopic exacerbation) and a higher Ulcerative Colitis Endoscopic Index of Severity vascular pattern score immediately after first CS (P = 0.021 for clinical relapse, P = 0.019 for endoscopic exacerbation) were risk factors for both clinical relapse and endoscopic exacerbation. CONCLUSIONS Therapeutic intervention for patients with UC with an MES of 1 might prevent disease relapse.
Endoscopy International Open | 2018
Ryoichi Miyanaga; Naoki Hosoe; Makoto Naganuma; Kenro Hirata; Seiichiro Fukuhara; Yoshihiro Nakazato; Keisuke Ojiro; Eisuke Iwasaki; Naohisa Yahagi; Haruhiko Ogata; Takanori Kanai
Background and study aims In Japan, the elderly population has been increasing annually. The number of elderly patients for whom esophagogastroduodenoscopy (EGD) and colonoscopy (CS) is indicated also has been rising. The aim of this study was to evaluate the safety and efficacy of routine endoscopy in a cohort of octogenarians aged 85 years and older – defined by the World Health Organization as the very elderly. Patients and methods A total of 5,586 patients underwent EGDs, and 2,484 patients underwent CSs performed at the Keio University Hospital from January to September 2014. One hundred eighty-five EGDs and 70 of the CS were performed in the very elderly. Six hundred nine EGDs and 262 CS were performed on younger patients (aged forties). Statistical analysis was performed by univariate and multivariate analyses. Results On univariate analysis, the rate of adverse events (AEs) in the very elderly was significantly higher compared to the younger group (6.3 % vs. 1.1 %; P < 0.01). Moreover, the very elderly cohort received substantial therapeutic intervention as compared to the younger (16.9 % vs. 6.9 %; P < 0.01). On multivariate analysis, independent risk factors of AEs included: very elderly patients (odds ratio (OR) 3.30, 95 % confidence interval (CI) 1.05 – 10.35), inpatients (OR 3.22, 95 % CI 1.34 – 7.74), and use of pethidine hydrochloride prescription (OR 3.44, 95 % CI 1.51 – 7.81). Conclusions Routine endoscopy in the very elderly incurs a significant risk of AEs, particularly when combined with pethidine hydrochloride prescription.
Case Reports in Gastroenterology | 2018
Yukie Sunata; Hideki Mori; Yuichiro Hirai; Yoko Kubosawa; Shigeo Banno; Satoshi Kinoshita; Yoshihiro Nakazato; Toshihiro Nishizawa; Masahiro Kikuchi; Toshio Uraoka
Atrial fibrillation (AF) is the most common cardiac arrhythmia, and cryoballoon ablation was developed as a new treatment modality for symptomatic AF. Gastroparesis is rarely reported as a transient complication of ablation, and its frequency and risk are not clear. We experienced a rare case of gastroparesis after cryoballoon ablation followed by medication-induced recovery within 6 months.
Internal Medicine | 2017
Kazuhiro Kashiwagi; Yoshihiro Nakazato; Mari Arai; Eisuke Iwasaki; Makoto Naganuma; Nagamu Inoue; Yasushi Iwao; Haruhiko Ogata; Koji Murakami; Takanori Kanai
Objective We investigated whether dual-time-point 18-Fluorodeoxyglucose (18FDG) positron emission tomography/computed tomography (PET/CT) could improve the positive predictive value for detecting advanced colorectal neoplasms (cancer, adenoma ≥10 mm or adenoma with high-grade dysplasia). Methods We retrospectively searched for consecutive patients with a known primary cancer, who had a colonic 18FDG uptake incidentally found by PET/CT, followed by colonoscopy between January 2013 and August 2014. The clinical characteristics including the maximum standardized uptake value (SUVmax) were compared between advanced colorectal neoplasms and non-advanced lesions. Results Forty-eight patients had 51 foci with an incidental focal colorectal uptake of 18FDG. Among these 51 foci, 28 foci were judged as being advanced neoplasms, whereas 23 foci identified as non-advanced lesions. Four cases were missed by PET/CT: two laterally spreading tumors (LSTs) with intramucosal cancer and two severe adenomas (<10 mm). The positive predictive value for the detection of advanced neoplasms was 55%. The per-spot performance of PET/CT showed that SUVmax was significantly higher in advanced neoplasms than in non-advanced lesions for the early-phase (10.1±4.9 vs. 6.5±3.2, p=0.029) and the delayed-phase (12.0±6.0 vs. 7.4±4.0, p=0.022). However, more importantly, there was a significant overlap of the SUVmax and no significant difference was found in the retention index (19.2±20.1 vs. 16.6±29.4, p=0.767). Conclusion Dual-time-point PET/CT was found to have limited impact for identifying advanced colorectal neoplasms in spite of its high sensitivity and it might therefore not be able to identify either LSTs or small advanced neoplasms.