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Featured researches published by Koichi Koizumi.
Blood | 2016
Kazuhiko Kakihana; Yuki Fujioka; Wataru Suda; Yuho Najima; Go Kuwata; Satoshi Sasajima; Iyo Mimura; Hidetoshi Morita; Daisuke Sugiyama; Hiroyoshi Nishikawa; Masahira Hattori; Yutaro Hino; Shuntaro Ikegawa; Keita Yamamoto; Takashi Toya; Noriko Doki; Koichi Koizumi; Kenya Honda; Kazuteru Ohashi
Increasing evidence indicates that the gut microbiota is closely associated with acute graft-versus-host disease (aGVHD) in stem cell transplantation (SCT). Fecal microbiota transplantation (FMT) could represent an alternative treatment option for aGVHD. However, FMT for SCT patients carries a potential risk of infection by infused microbiota because of the severely immunosuppressed status. We therefore conducted a pilot study to evaluate the safety of FMT in SCT. A total of 4 patients with steroid-resistant (n = 3) or steroid-dependent gut aGVHD (n = 1) received FMT. No severe adverse events attributed to FMT were observed. All patients responded to FMT, with 3 complete responses and 1 partial response. Temporal dynamics of microbiota seemed to be linked to the gut condition of patients and peripheral effector regulatory T cells also increased during response to FMT. FMT was safely performed in our patients and might offer a novel therapeutic option for aGVHD. This trial was registered at the University Hospital Medical Information Network (https://upload.umin.ac.jp/cgi-open-bin/icdr_e/ctr_view.cgi?recptno=R000017575) as #UMIN000015115.
International Journal of Clinical Oncology | 2004
Takeo Iwama; Kazuo Tamura; Takayuki Morita; Takashi Hirai; Hirotoshi Hasegawa; Koichi Koizumi; Kenichi Sugihara; Takehira Yamamura; Tetsuichiro Muto; Joji Utsunomiya; Rectum
The clinical situation of familial adenomatous polyposis (FAP) in Japan has changed in the period since the last analysis of data of the Japanese Polyposis Center. To reevaluate our data and elucidate the changes we analyzed the records of the 1390 FAP patients in 900 families registered with the Polyposis Committee of the Japanese Society for Cancer of the Colon and Rectum. In the 13-year period 1990–2003, clinical differences between men and women with FAP diminished. The postoperative prognosis was substantially better in patients without advanced colorectal cancer (stage ≧ T2) than in those with early cancer or no cancer. Mean age at death improved from 42.5 years in the period before 1990 to 46.0 years, and it was a result of a decreased proportion of deaths from colorectal cancer. The distribution of colorectal cancer in FAP patients was similar to that in the general population. Desmoid tumors accounted for about 10% of deaths in the recent 13 years (1990–2003). The cumulative risk of rectal cancer in the preserved rectum was 12% at 10 years and 23% at 15 years. The registry system in Japan revealed a new clinical situation in FAP patients, and the findings of this study will be useful to improve the prognosis of patients with FAP.
World Journal of Gastroenterology | 2013
Satomi Koizumi; Terumi Kamisawa; Sawako Kuruma; Taku Tabata; Kazuro Chiba; Susumu Iwasaki; Yuka Endo; Go Kuwata; Koichi Koizumi; Tooru Shimosegawa; Kazuichi Okazaki; Tsutomu Chiba
In immunoglobulin G4 (IgG4)-related disease (RD), organ enlargement or nodular lesions consisting of abundant infiltration of lymphocytes and IgG4-positive plasma cells and fibrosis are seen in various organs. Although infiltration of many IgG4-positive plasma cells is detected in the gastric and colonic mucosa and major duodenal papilla of patients with autoimmune pancreatitis, it cannot be diagnosed as a gastrointestinal lesion involved in IgG4-RD, because none of the following is observed in these lesions: a mass-like formation; dense fibrosis; or obliterative phlebitis. Based on our review of the literature, there appear to be two types of IgG4-related gastrointestinal disease. One is a gastrointestinal lesion showing marked thickening of the wall of the esophagus and stomach, consisting of dense fibrosis with abundant infiltration of IgG4-positive plasma cells, which usually show submucosal spreading. The other is an IgG4-related pseudotumor occurring in gastrointestinal regions such as the stomach, colon, and major duodenal papilla, showing polypoid or mass-like lesions. Most solitary IgG4-related gastrointestinal lesions that are not associated with other IgG4-RD appear to be difficult to diagnose. It is of utmost importance to rule out malignancy. However, these lesions may respond to steroid therapy. To avoid unnecessary resection, IgG4-related gastrointestinal diseases should be considered in the differential diagnosis.
Gut and Liver | 2012
Yuji Miyamoto; Terumi Kamisawa; Taku Tabata; Seiichi Hara; Sawako Kuruma; Kazuro Chiba; Yoshihiko Inaba; Go Kuwata; Takashi Fujiwara; Hideto Egashira; Koichi Koizumi; Ryoko Sekiya; Junko Fujiwara; Takeo Arakawa; Kumiko Momma; Toru Asano
Background/Aims Autoimmune pancreatitis (AIP) is frequently associated with diabetes mellitus (DM). This study evaluated the effect of steroid therapy on the course of DM in AIP. Methods Glucose tolerance was examined in 69 patients with AIP. DM onset was classified as either a simultaneous onset with AIP or an exacerbation of pre-existing DM. Based on the changes in the HbA1c levels and insulin dose, the responses of DM to steroids were classified as improved, no change, or worsened. Results Thirty (46%) patients were diagnosed as having DM (simultaneous onset, n=17; pre-existing, n=13). Three months after starting the steroid treatment, the DM improved in 13 (54%) of 24 DM patients. The DM improved in 55%, had no change in 36%, and worsened in 9% of the 11 simultaneous onset DM patients, and it improved in 54%, had no change in 31%, and worsened in 15% of the 13 pre-existing DM patients. At approximately 3 years after starting the steroid treatment, the DM improved in 10 (63%) of 16 patients. The pancreatic exocrine function improved in parallel with the changes in the DM in seven patients. Conclusions Because approximately 60% of DM associated with AIP is responsive to steroids in the short- and long-terms, marked DM associated with AIP appears to be an indication for steroid therapy.
Pancreatology | 2013
Taku Tabata; Terumi Kamisawa; Seiichi Hara; Sawako Kuruma; Kazuro Chiba; Go Kuwata; Takashi Fujiwara; Hideto Egashira; Satomi Koizumi; Yuka Endo; Koichi Koizumi; Junko Fujiwara; Takeo Arakawa; Kumiko Momma; Shinichiro Horiguchi; Tsunekazu Hishima; Masanao Kurata; Goro Honda; Günter Klöppel
BACKGROUND/AIMS Coexistence of autoimmune pancreatitis (AIP) and pancreatic cancer, elevation of serum IgG4 levels in pancreatic cancer patients, and infiltration of IgG4-positive plasma cells in peritumorous pancreatitis have been described in a few reports. This study examined the relationship between intraductal papillary mucinous neoplasm (IPMN) of the pancreas and peritumorous IgG4-positive lymphoplasmacytic infiltrates. METHODS Serum IgG4 levels were measured in 54 patients with IPMN (median 70 years, 26 males and 28 females; 13 main duct type and 41 branch duct type). Histological findings focusing on dense lymphoplasmacytic infiltration, storiform fibrosis, and obliterative phlebitis were reviewed, and immunostaining with IgG4 and IgG was performed in 23 surgically resected IPMN cases (18 main duct type and 5 branch duct type). The presence of IgG4-positive plasma cells >10/hpf and an IgG4-positive/IgG-positive plasma cell ratio >40% were considered significant. RESULTS Serum IgG4 levels were elevated in 2 (4%) IPMN patients. Significant infiltration of IgG4-positive plasma cells was detected in 4 IPMN cases (17%). The IgG4-positive/IgG-positive plasma cell ratio was >40% in all 4 cases. In one case with a markedly elevated serum IgG4 level (624 mg/dL), typical lymphoplasmacytic sclerosing pancreatitis (AIP type 1) lesions surrounded the whole IPMN. In the 3 other cases, infiltration of IgG4-positive plasma cells with fibrosis was focally detected mainly in the periductal area around the IPMN. CONCLUSIONS In a few patients with IPMNs, IgG4-positive plasma cell infiltration can occur in the peritumorous area. The association of an IPMN with AIP type 1-like changes seems to be exceptional and coincidental.
Gastrointestinal Endoscopy | 2015
Matsuzawa T; Hideyuki Ishida; Shuntaro Yoshida; Hiroyuki Isayama; Toshio Kuwai; Iruru Maetani; Mamoru Shimada; Tomonori Yamada; Shuji Saito; Masafumi Tomita; Koichi Koizumi; Nobuto Hirata; Takashi Sasaki; Toshiyuki Enomoto; Yoshihisa Saida
BACKGROUND Endoscopic self-expandable metal stent placement has been used as an alternative to surgery for malignant colorectal obstruction; however, factors affecting its clinical outcome are unclear. OBJECTIVE To clarify the short-term safety and efficacy of endoscopic self-expandable metal stent placement for malignant colorectal obstruction and to identify factors associated with its clinical and technical failure. DESIGN Prospective clinical cohort study. SETTING Fourteen academic centers and 32 community hospitals. PATIENTS A total of 513 consecutive patients with malignant colorectal obstruction. INTERVENTION Endoscopic self-expandable metal stent placement, sharing of stent placement methods among participating facilities. MAIN OUTCOME MEASUREMENTS The primary endpoint was clinical success, defined as symptom and radiological finding resolution within 24 hours. Secondary endpoints were technical success and adverse events. The follow-up period was 7 days. RESULTS The clinical and technical success rates were 95.5% and 97.9%, respectively. Major adverse events included perforation (2.1%), stent migration (1.0%), and stent occlusion (0.8%). The main causes of perforation were the procedure itself (0.8%) and comorbidities (obstructive colitis and impending perforation) not apparent before stent placement (0.6%). Extrinsic tumor origin was independently associated with the clinical failure after stent placement (odds ratio 4.23; 95% confidence interval, 1.21-14.79; P = .02). Stricture marking trended toward a negative association with technical failure (P = .09). LIMITATIONS Noncomparative study. CONCLUSION Strict inclusion criteria and stricture marking may improve the technical and clinical success of stent placement.
Gut and Liver | 2013
Taku Tabata; Terumi Kamisawa; Seiichi Hara; Sawako Kuruma; Kazuro Chiba; Go Kuwata; Takashi Fujiwara; Hideto Egashira; Koichi Koizumi; Junko Fujiwara; Takeo Arakawa; Kumiko Momma; Masanao Kurata; Goro Honda; Koji Tsuruta; Takao Itoi
Background/Aims Few studies have differentiated immunoglobulin G (IgG) 4-related sclerosing cholangitis (IgG4-SC) from hilar cholangiocarcinoma (CC). Thus, we sought to investigate useful features for differentiating IgG4-SC from hilar CC. Methods We retrospectively compared clinical, serological, imaging, and histological features of six patients with IgG4-SC and 42 patients with hilar CC. Results In patients with hilar CC, obstructive jaundice was more frequent (p<0.01), serum total bilirubin levels were significantly higher (p<0.05), serum CA19-9 levels were significantly higher (p<0.01), and serum duke pancreatic monoclonal antigen type 2 levels were frequently elevated (p<0.05). However, in patients with IgG4-SC, the serum IgG (p<0.05) and IgG4 (p<0.01) levels were significantly higher and frequently elevated. The pancreas was enlarged in all IgG4-SC patients but only in 17% of hilar CC patients (p<0.01). Salivary and/or lacrimal gland swelling was detected in only 50% of IgG4-SC patients (p<0.01). Endoscopic retrograde cholangiography revealed that the hilar or hepatic duct was completely obstructed in 83% of hilar CC patients (p<0.01). Lower bile duct stenosis, apart from hilar bile duct stenosis, was more frequent in IgG4-SC patients (p<0.01). Bile duct wall thickening in areas without stenosis was more frequent in IgG4-SC patients (p<0.01). Conclusions An integrated diagnostic approach based on clinical, serological, imaging, and histological findings is necessary to differentiate IgG4-SC from hilar CC.
Gut and Liver | 2013
Sawako Kuruma; Terumi Kamisawa; Taku Tabata; Seiichi Hara; Takashi Fujiwara; Go Kuwata; Hideto Egarashira; Koichi Koizumi; Keigo Setoguchi; Junko Fujiwara; Takeo Arakawa; Kumiko Momma; Toshio Mitsuhashi; Tsuneo Sasaki
Background/Aims The objective of this study was to compare the clinical characteristics of patients with autoimmune pancreatitis (AIP) with or without Mikuliczs disease (MD) and with MD alone. Methods We investigated the clinical findings in 15 AIP patients with MD (group A+M), 49 AIP only patients (group A), and 14 MD only patients (group M). Results The male-female ratio was significantly higher in group A+M (73%, p<0.05) and group A (78%, p<0.01) than group M (21%). Serum immunoglobulin G (IgG) levels were significantly higher in group A+M than in group A (p<0.01) and group M (p<0.05). Serum IgG4 levels were significantly higher in group A+M than in group A (p<0.01). Other organ involvement was observed in 73% (11/15) of patients in group A+M. The number of patients with diabetes mellitus was significantly higher in group A+M (66%, p<0.01) and group A (51%, p<0.05) than in group M (7%). All of the patients responded well to steroid therapy, but the relapse rate in group A+M (33%) was significantly higher than that in group A (3%, p<0.01). Salivary gland function was impaired in all groups compared with the control group, but the degree of dysfunction was less in group A compared with group A+M and group M. Conclusions The relapse rate of AIP in MD patients was significantly higher than that of AIP in patients without MD.
Journal of Korean Medical Science | 2015
Satomi Koizumi; Terumi Kamisawa; Sawako Kuruma; Taku Tabata; Kazuro Chiba; Susumu Iwasaki; Go Kuwata; Takashi Fujiwara; Junko Fujiwara; Takeo Arakawa; Koichi Koizumi; Kumiko Momma
IgG4-related disease (IgG4-RD) is a potentially multiorgan disorder. In this study, clinical and serological features from 132 IgG4-RD patients were compared about organ correlations. Underlying pathologies comprised autoimmune pancreatitis (AIP) in 85 cases, IgG4-related sclerosing cholangitis (IgG4-SC) in 12, IgG4-related sialadenitis (IgG4-SIA) in 56, IgG4-related dacryoadenitis (IgG4-DAC) in 38, IgG4-related lymphadenopathy (IgG4-LYM) in 20, IgG4-related retroperitoneal fibrosis (IgG4-RF) in 19, IgG4-related kidney disease (IgG4-KD) in 6, IgG4-related pseudotumor (IgG4-PT) in 3. Sixty-five patients (49%) had multiple IgG4-RD (two affected organs in 36 patients, three in 19, four in 8, five in 1, and six in 1). Serum IgG4 levels were significantly higher with multiple lesions than with a single lesion (P<0.001). The proportion of association with other IgG4-RD was 42% in AIP, the lowest of all IgG4-RDs. Serum IgG4 level was lower in AIP than in other IgG4-RDs. Frequently associated IgG4-RDs were SIA (25%) and DAC (12%) for AIP; AIP (75%) for IgG4-SC; DAC (57%), AIP (38%) and LYM (27%) for IgG4-SIA; AIP (26%) and LYM (26%) for IgG4-DAC; SIA (75%), DAC (50%) and AIP (45%) for IgG4-LYM; SIA (58%), AIP (42%) and LYM (32%) for IgG4-RF; AIP (100%) and SIA (67%) for IgG4-KID; and DAC (67%) and SIA (67%) for IgG4-PT. Most associated IgG4-RD lesions were diagnosed simultaneously, but IgG4-SIA and IgG4-DAC were sometimes identified before other lesions. About half of IgG4-RD patients had multiple IgG4-RD lesions, and some associations were seen between specific organs. Graphical Abstract
Gut and Liver | 2014
Go Kuwata; Terumi Kamisawa; Koichi Koizumi; Taku Tabata; Seiichi Hara; Sawako Kuruma; Takashi Fujiwara; Kazuro Chiba; Hideto Egashira; Junko Fujiwara; Takeo Arakawa; Kumiko Momma; Shinichiro Horiguchi
Background/Aims Ulcerative colitis (UC) is sometimes associated with autoimmune pancreatitis (AIP). Infiltration of immunoglobulin G4 (IgG4)-positive plasma cells is sometimes detected in the colonic mucosa of AIP or UC patients. This study aimed to clarify the relation between UC and IgG4. Methods Associations with UC were reviewed in 85 AIP patients. IgG4 immunostaining was performed on biopsy specimens from the colonic mucosa of 14 AIP and 32 UC patients. Results UC was confirmed in two cases (type 1 AIP, n=1; suspected type 2 AIP, n=1). Abundant infiltration of IgG4-positive plasma cells in the colonic mucosa was detected in the case of suspected type 2 AIP with UC and two cases of type 1 AIP without colitis. Abundant infiltration of IgG4-positive plasma cells was detected in 10 UC cases (IgG4-present, 31%). Although 72% of IgG4-absent UC patients showed mild disease activity, 70% of IgG4-present patients showed moderate to severe disease activity (p<0.05). Conclusions UC is sometimes associated with AIP, but it seems that UC is not a manifestation of IgG4-related disease. Infiltration of IgG4-positive plasma cells is sometimes detectable in the colonic mucosa of UC patients and is associated with disease activity.