Immunochip analysis identification of 6 additional susceptibility loci for Crohn's disease in Koreans.

BACKGROUND: Crohn's disease (CD) is an intractable inflammatory bowel disease of unknown cause. Recent genome-wide association studies of CD in Korean and Japanese populations suggested marginal sharing of susceptibility loci between Caucasian and Asian populations. As the 7 identified loci altogether explain 5.31% of the risk for CD, the objective of this study was to identify additional CD susceptibility loci in the Korean population. METHODS: Using the ImmunoChip custom single-nucleotide polymorphism array designed for dense genotyping of 186 loci identified through GWAS, we analyzed 722 individuals with CD and 461 controls for 96,048 SNP markers in the discovery stage, followed by validation in an additional 948 affected individuals and 977 controls. RESULTS: We confirmed 6 previously reported loci in Caucasian: GPR35 at 2q37 (rs3749172; P = 5.30 × 10, odds ratio [OR] = 1.45), ZNF365 at 10q21 (rs224143; P = 2.20 × 10, OR = 1.38), ZMIZ1 at 10q22 (rs1250569; P = 3.05 × 10, OR = 1.30), NKX2-3 at 10q24 (rs4409764; P = 7.93 × 10, OR = 1.32), PTPN2 at 18p11 (rs514000; P = 9.00 × 10, OR = 1.33), and USP25 at 21q11 (rs2823256; P = 2.49 × 10, OR = 1.35), bringing the number of known CD loci (including 3 in the HLA) in Koreans to 15. The 6 additional loci increased the total genetic variance for CD risk from 5.31% to 7.27% in Koreans. CONCLUSIONS: Although the different genetic backgrounds of CD between Asian and Western countries has been well established for the major susceptibility genes, our findings of overlapping associations offer new insights into the genetic architecture of CD.

Risk of adenomas with high-risk characteristics based on two previous colonoscopy.

BACKGROUND AND AIM: The recommended intervals between surveillance colonoscopies are based on the most recent examination findings. However, whether the two previous colonoscopies affect second surveillance colonoscopic findings is not established. The aim of this study is to estimate the risk of obtaining high-risk findings (HRF) on the next surveillance colonoscopy using the results of two previous colonoscopies, and to estimate the appropriate time interval for the next surveillance colonoscopy. METHODS: Among subjects who underwent screening colonoscopy during January 2002-December 2009, patients who underwent second surveillance colonoscopy before June 2012 were enrolled. "No adenoma" was defined as a hyperplastic polyp or no polyp, "low-risk findings (LRF)" as one or two small (< 1 cm) tubular adenomas, and "HRF" as advanced adenoma, cancer, or any sized multiple (≥ 3) adenomas. RESULTS: Among enrolled 852 subjects, 65 (7.6%) had HRF at second surveillance colonoscopy. Multivariate analysis showed that HRF on second surveillance colonoscopy were associated with male and HRF on screening colonoscopy (all, P < 0.01). In subjects with LRF on first surveillance colonoscopy, HRF on the screening colonoscopy significantly affected the detection of HRF on second surveillance colonoscopy (P < 0.01). Patients with HRF on screening colonoscopy and LRF on the first surveillance colonoscopy had no different risk of HRF on second surveillance colonoscopy from those with HRF on first surveillance colonoscopy (P > 0.05). CONCLUSIONS: The HRF on second surveillance are significantly associated with previous two colonoscopic results. In patients with LRF on first surveillance, screening colonoscopic findings should be considered to determine the optimal surveillance interval.

Is propofol safe when administered to cirrhotic patients during sedative endoscopy?

BACKGROUND/AIMS: In patients with liver cirrhosis, drugs acting on the central nervous system can lead to hepatic encephalopathy and the effects may be prolonged. Recently, misuse of propofol has been reported and the associated risk of death have become an issue. Propofol is commonly used during sedative endoscopy; therefore, its safety in high-risk groups must be further investigated. We performed a pilot study of the safety and efficacy of propofol during endoscopy in Korean patients with cirrhosis. METHODS: Upper gastrointestinal endoscopy was performed under sedation with propofol along with careful monitoring in 20 patients with liver cirrhosis and 20 control subjects. The presence or development of hepatic encephalopathy was assessed using the number connection test and neurologic examination. RESULTS: Neither respiratory depression nor clinically significant hypotension were observed. Immediate postanesthetic recovery at 5 and 10 minutes after the procedure was delayed in the cirrhotic patients compared with the control group; however, at 30 minutes, the postanesthetic recovery was similar in both groups. Baseline psychomotor performance was more impaired in cirrhotic patients, but propofol was not associated with deteriorated psychomotor function even in cirrhotic patients with a minimal hepatic encephalopathy. CONCLUSIONS: Sedation with propofol was well tolerated in cirrhotic patients. No newly developed hepatic encephalopathy was observed.

Incidences of serious infections and tuberculosis among patients receiving anti-tumor necrosis factor-α therapy.

PURPOSE: Anti-tumor necrosis factor-alpha (TNF-α) medications represent a major advancement in the management of chronic inflammatory diseases. However, these agents are associated with increased risks of tuberculosis (TB) and other serious infections. The aim of this study was to evaluate the incidences of such disease among tertiary hospitals in Korea. MATERIALS AND METHODS: We retrospectively studied patients who received anti-TNF-α therapy; we reviewed serious infections including TB that developed within 6 months after initiation of anti-TNF-α therapy. Data concerning patient demographics, types of anti-TNF-α agents, concomitant immunosuppressive drugs use, and infection details were collected. RESULTS: A total 175 patients treated with infliximab (n=72) or adalimumab (n=103) with the following conditions were enrolled: Crohn's disease, 34 (19.4%); ulcerative colitis, 20 (11.4%); ankylosing spondylitis, 82 (46.9%); and rheumatoid arthritis, 39 (22.2%). There were 18 cases (6.0%) of serious infections. The most common site of serious infection was the intra-abdomen (n=6), followed by TB (n=3), skin and soft tissue (n=3), bone and joints (n=2), ocular neurons (n=2), lower respiratory tract (n=1), and urinary tract (n=1). Of the 175 patients, only 3 cases showed development of TB. Furthermore, of all those who developed TB, none had taken anti-TB chemoprophylaxis prior to treatment with an anti-TNF agent due to negative screening results. CONCLUSION: Serious infections with anti-TNF-α therapy were uncommon among tertiary hospitals in Korea; TB was the second most frequent infection. Nevertheless, there were no TB reactivations after anti-TB chemoprophylaxis. Accordingly, physicians should be aware of TB in subjects undergoing anti-TNF-α therapy, especially in countries with a high prevalence of TB.

Two cases of uncommon complication during percutaneous endoscopic gastrostomy tube replacement and treatment.

We presented two interesting cases of gastrocolocutaneous fistula that occurred after percutaneous endoscopic gastrostomy (PEG) tube placement, and its management. This fistula is a rare complication that occurs after PEG insertion, which is an epithelial connection between mucosa of the stomach, colon, and skin. The management of the fistula is controversial, ranging from conservative to surgical intervention. Endoscopists should be aware of the possibility of gastrocolocutaneous fistula after PEG insertion, and should evaluate the risk factors that may contribute to the development of gastrocolocutaneous fistula before the procedure. We reviewed complications of gastrostomy tube insertion, symptoms of gastrocolocutaneous fistula, and its risk factors.

Genome-wide association study of Crohn's disease in Koreans revealed three new susceptibility loci and common attributes of genetic susceptibility across ethnic populations.

OBJECTIVE: Crohn's disease (CD) is an intractable inflammatory bowel disease (IBD) of unknown cause. Recent meta-analysis of the genome-wide association studies (GWAS) and Immunochip data identified 163 susceptibility loci to IBD in Caucasians, however there are limited studies in other populations. METHODS: We performed a GWAS and two validation studies in the Korean population comprising a total of 2311 patients with CD and 2442 controls. RESULTS: We confirmed four previously reported loci: TNFSF15, IL23R, the major histocompatibility complex region, and the RNASET2-FGFR1OP-CCR6 region. We identified three new susceptibility loci at genome-wide significance: rs6856616 at 4p14 (OR=1.43, combined p=3.60×10(-14)), rs11195128 at 10q25 (OR=1.42, combined p=1.55×10(-10)) and rs11235667 at 11q13 (OR=1.46, combined p=7.15×10(-9)), implicating ATG16L2 and/or FCHSD2 as novel susceptibility genes for CD. Further analysis of the 11q13 locus revealed a non-synonymous single nucleotide polymorphism (SNP) (R220W/rs11235604) in the evolutionarily conserved region of ATG16L2 with stronger association (OR=1.61, combined p=2.44×10(-12)) than rs11235667, suggesting ATG16L2 as a novel susceptibility gene for CD and rs11235604 to be a potential causal variant of the association. Two of the three SNPs (rs6856616 (p=0.00024) and rs11195128 (p=5.32×10(-5))) showed consistent patterns of association in the International IBD Genetics Consortium dataset. Together, the novel and replicated loci accounted for 5.31% of the total genetic variance for CD risk in Koreans. CONCLUSIONS: Our study provides new biological insight to CD and supports the complementary value of genetic studies in different populations.

Development of enterohepatic fistula after embolization in ileal gastrointestinal stromal tumor: a case report.

Gastrointestinal stromal tumor (GIST) is a rare mesenchymal tumor of the gastrointestinal tract that has been associated with the formation of fistulas to adjacent organs in few case reports. However, GIST with enterohepatic fistula has not been reported. Here we report the case of an enterohepatic fistula that occurred after embolization of a liver mass originating in the distal ileum. An 87-year-old woman was hospitalized for melena. On initial conventional endoscopy, a bleeding focus in the gastrointestinal tract was not found. Because of massive hematochezia, enteroscopy was performed through the anus. A protruding, ulcerative mass was found in the distal ileum that was suspected to be the source of the bleeding; a biopsy sample was taken. Electrocoagulation was not successful in controlling the bleeding; therefore, embolization was performed. After embolization, the patient developed a high fever and severe abdominal tenderness with rebound tenderness. Follow-up abdominopelvic computed tomography revealed an enterohepatic fistula between the liver and distal ileum. The fistula was treated surgically by segmental resection of the distal ileum and unlooping of the liver mass.

Is colonoscopic screening necessary for patients with gastric adenoma or cancer?

BACKGROUND: Since colorectal adenoma or cancer is commonly associated with gastric adenoma or cancer, early colorectal adenoma detection can affect the survival of gastric adenoma or cancer patients. AIMS: The purpose here was to investigate the colorectal adenoma or cancer prevalence and evaluate the necessity for screening colonoscopy in gastric adenoma or cancer patients. PATIENTS AND METHODS: From September 2005 through August 2010, 857 patients younger than 70 years who had gastric adenoma or cancer were enrolled. Healthy age- and sex-matched controls were selected from the general screening population. The prevalence and risk of colorectal adenoma or cancer were compared between the participants and the controls. RESULTS: Data from 416 patients in the gastric neoplasm group (123 with gastric adenoma and 293 with gastric cancer) and 416 healthy control group participants were included in the statistical analysis. The presence of gastric adenoma or cancer was an independent risk factor for colorectal neoplasm (OR = 1.348, 95 % CI = 1.001-1.815). Patients with diffuse type gastric cancer had a lower prevalence of colorectal adenoma or cancer than those with gastric adenoma or intestinal type cancer. In gastric cancer patients younger than 50 years, intestinal type histology was significantly associated with colorectal adenoma or cancer (OR = 3.838, 95 % CI = 1.077-13.677). CONCLUSIONS: The colorectal adenoma or cancer risk was significantly increased in patients with gastric adenoma or cancer. Therefore, screening colonoscopy should be considered for gastric adenoma or cancer patients including young patients, in the case of intestinal type gastric cancer.

Small bowel pseudomelanosis associated with oral iron therapy.

An accumulation of pigment deposits on mucosa, called melanosis or pseudomelanosis, of the small bowel is observed infrequently during endoscopic examination. We describe 6 cases of small bowel pseudomelanosis; the possible etiology of which was chronic iron intake. We observed numerous brown spots in duodenum, jejunum, and terminal ileum during upper and lower endoscopy. Interestingly, all patients have been taking oral iron for several years. Histology showed pigment depositions within macrophages of the lamina propria and a positive Prussian blue stain indicating hemosiderin deposition. Herein, we demonstrate that long term iron therapy may result in pseudomelanosis of small bowel, such as duodenum, jejunum, and ileum.

Intensified rehabilitation therapy and transitions to skilled nursing facilities in community-living seniors with acute medical illnesses.

AIM: To examine whether rehabilitation therapy type would be associated with transitions to skilled nursing facilities (SNF) in community-living seniors with acute medical illnesses. METHODS: Using administrative and clinical data, multivariate regression analysis examined the relationship between the extent of rehabilitation therapy and transitions to SNF in all participants, as well as participants by physical function at admission. RESULTS: In all participants (n=929), the intensified rehabilitation therapy was associated with a lower probability of transitions to SNF (14% vs 21%; odds ratio [OR] 0.59; 95% confidence intervals [CI] 0.22-0.96; P=0.02). In participants with mild physical limitations (n=270), less frequent transitions to SNF occurred when patients received intensified rehabilitation therapy [16% vs 23%; OR 0.46; 95% CI 0.17-0.94; P=0.01]. In participants with moderate to severe physical limitations (n=265), the decreased frequency of transitions to SNF associated with rehabilitation therapy became more pronounced (18% vs 28%; OR 0.34; 95% CI 0.07-0.89; P=0.004). By contrast, in participants without physical limitation (n=394), the number of transitions to SNF did not change significantly when they received intensified rehabilitation therapy (P=0.53). CONCLUSIONS: We found a significant relationship between intensified rehabilitation therapy and the decrease of transitions to SNF in community-living seniors with acute medical illness. The magnitude of this relationship increased in participants with more physical limitations, but not in participants without physical limitations at admission.

Comparative study of Helicobacter pylori eradication rates with 5-day quadruple "concomitant" therapy and 7-day standard triple therapy.

BACKGROUND: Several studies have shown the superiority of concomitant quadruple therapy containing 3 antibiotics over triple therapy for Helicobacter pylori infection. The aim of this study was to compare concomitant quadruple therapy with standard triple therapy for first-line H. pylori eradication. METHODS: A total of 270 patients with proven H. pylori infection were randomly assigned to one of 2 regimens: amoxicillin 1000 mg with clarithromycin 500 mg and lansoprazole 30 mg twice daily for 7 days (triple therapy) or amoxicillin 1000 mg with clarithromycin 500 mg, metronidazole 500 mg, and lansoprazole 30 mg twice daily for 5 days (concomitant therapy). The success of eradication was evaluated 4 to 5 weeks after completion of treatment. RESULTS: Eradication rates were 86.1% in the triple therapy and 91.4% in the concomitant therapy (per protocol), but the difference was not statistically significant. Mild adverse events were more frequently reported in the concomitant-therapy group (35.6%) than in the triple-therapy group (25.2%) (P=0.09). CONCLUSIONS: Five-day quadruple concomitant therapy eradicated H. pylori in over 90% of patients. Accordingly, concomitant therapy is thought to be a promising alternative to triple therapy as a first-line treatment regimen for H. pylori eradication.

Severe ischemic bowel necrosis caused by terlipressin during treatment of hepatorenal syndrome.

Terlipressin is a vasopressin analogue that is widely used in the treatment of hepatorenal syndrome or variceal bleeding. Because it acts mainly on splanchnic vessels, terlipressin has a lower incidence of severe ischemic complications than does vasopressin. However, it can still lead to serious complications such as myocardial infarction, skin necrosis, or bowel ischemia. Herein we report a case of severe ischemic bowel necrosis in a 46-year-old cirrhotic patient treated with terlipressin. Although the patient received bowel resection, death occurred due to ongoing hypotension and metabolic acidosis. Attention should be paid to patients complaining of abdominal pain during treatment with terlipressin.

The Effects of Combined Treatment with an HMG-CoA Reductase Inhibitor and PPARγ Agonist on the Activation of Rat Pancreatic Stellate Cells.

BACKGROUND/AIMS: Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) and peroxisome proliferator-activated receptor gamma (PPARγ) ligands can modulate cellular differentiation, proliferation, and apoptosis through various pathways. It has been shown that HMG-CoA reductase inhibitors and PPARγ agonists separately inhibit pancreatic stellate cell (PaSC) activation. We studied the effects of a combination of both types of drugs on activated PaSCs via platelet-derived growth factor (PDGF), which has not previously been reported. The present study was performed to elucidate the underlying mechanisms of these effects by focusing on the impact of the signaling associated with cell-cycle progression. METHODS: Primary cultures of rat PaSCs were exposed to simvastatin and troglitazone. Proliferation was quantified using the BrdU method, and cell-cycle analysis was performed using a fluorescent activated cell sorter. The protein expression levels of smooth muscle actin (SMA), extracellular signal-regulated kinase (ERK), and a cell cycle machinery protein (p27Kip1) were investigated using Western blot analysis. RESULTS: Simvastatin reversed the effects of PDGF on cell proliferation in a dose-dependent manner. The combination of a low concentration of simvastatin (1 mM) and troglitazone (10 mM) synergistically reversed the effects of PDGF on cell proliferation but had no effect on cell viability. The expression of a-SMA was markedly attenuated by combining the two drugs, which blocked the cell cycle beyond the G0/G1 phase by reducing the levels of phosphorylated ERK and reversed the expression of p27Kip1 interrupted by PDGF. CONCLUSIONS: Simvastatin and troglitazone synergistically inhibited cell proliferation in activated PaSCs by blocking the cell cycle beyond the G0/G1 phase. This inhibition was due to the synergistic modulation of the ERK pathway and the cell cycle machinery protein p27Kip1.

Effectiveness of three times daily lansoprazole/amoxicillin dual therapy for Helicobacter pylori infection in Korea.

AIM: We compared three times daily dual therapy with standard triple therapy for effectiveness and safety in H. pylori infection. METHODS: Two hundred and four H. pylori positive patients with peptic ulcer were randomly assigned to one of two regimens: (i) triple therapy with amoxicillin, clarithromycin and lansoprazole twice daily for 2 weeks or (ii) dual therapy with amoxicillin and lansoprazole three times daily for 2 weeks. The success of eradication was evaluated 4 to 5 weeks after completing treatment. RESULTS: The eradication rate was 82.8% in the triple therapy group and 78.4% in the dual therapy group by per protocol analysis. This difference was not significant (P= 0.573). Adverse events were more frequent in the triple therapy group than in the dual therapy group (P= 0.002). CONCLUSIONS: Because dual therapy had fewer side effects than triple therapy and a similar eradication rate, dual therapy may provide an acceptable alternative first line therapy for H. pylori eradication in Korea.

Small bowel carcinoma in young patient detected by double-balloon enteroscopy.

A 17-year old female presented with a chief complaint of melena and epigastric pain. She had a family history of colon cancer, her mother having been diagnosed with hereditary nonpolyposis colorectal carcinoma (HNPCC). After close examination including double-balloon enteroscopy, the patient was diagnosed with small bowel carcinoma, in spite of her young age. Here we report this rare case of small bowel carcinoma in a young patient with a family history of HNPCC.

Effectiveness and safety of repeated quadruple therapy in Helicobacter pylori infection after failure of second-line quadruple therapy: repeated quadruple therapy as a third-line therapy.

BACKGROUNDS: Quadruple therapy using a proton-pump inhibitor, bismuth, metronidazole, and tetracycline is a standard second-line therapy for Helicobacter pylori infection, achieving an eradication rate of about 80% in Korea. A standard third-line therapy is not currently established, although various protocols have been proposed. We performed this study to evaluate the effectiveness of a retrial with quadruple therapy before starting a third-line treatment with new drugs. MATERIALS AND METHODS: In 80 of 746 patients treated with a second-line quadruple therapy at the Korea University Ansan Hospital between January 2002 and September 2010, treatment for H. pylori had failed, and 45 of these patients were eligible for this study. Eradication of H. pylori was assessed by repeated endoscopy or by the (13) C-urea breath test at least 4 weeks after therapy. The patients with treatment failure were treated again with quadruple regimen for 2 weeks and reevaluated for treatment effectiveness and safety. RESULTS: The eradication rate with second-line quadruple therapy was 86.9%. Of the 80 patients who failed treatment for H. pylori with the initial second-line quadruple therapy, 64 patients were treated again with the same regimen. Of the 45 retreated patients in this study, three patients were lost to follow-up and two complied poorly with medication. The eradication rate in the 40 patients retreated was 75.0% at per-protocol analysis. Seventeen patients experienced mild adverse events. CONCLUSIONS: A retrial of quadruple therapy before use of a third-line therapy may be safe and effective for patients who fail to respond to second-line quadruple therapy.

Clinical characteristics of small bowel tumors diagnosed by double-balloon endoscopy: KASID multi-center study.

BACKGROUND: Small bowel tumors are relatively rare, and their confirmative diagnosis before surgery is not easy. AIMS: This study was performed to investigate the clinical characteristics of patients with small bowel tumors who received double-balloon enteroscopy (DBE). Secondary end points were to evaluate the usefulness and safety of DBE for the diagnosis of patients with suspected SB tumors derived from other previous procedures. METHODS: We retrospectively analyzed consecutive DBE examinations to explore the small intestine in eight university hospitals over a 5-year period. RESULTS: A total of 877 DBE examinations (per oral 487, per anal 390) were performed in 645 patients (405 males, mean age 48.2 years). Small bowel tumors were diagnosed in 112 patients (17.4%), of which 38 patients had benign polyps, 29 had gastrointestinal stromal tumors/leiomyomata, 18 had lymphomas, 14 had adenocarcinomas, five had metastatic or invasive cancers, five had lipomas, and three patients had cystic tumors. The main reasons for DBE among patients with small bowel tumors were obscure gastrointestinal bleeding (OGIB, 40.2%) followed by abnormal imaging study (25.2%). The concordance rate of diagnoses based on DBE with diagnoses based on small bowel follow-through, CT, and capsule endoscopy among patients with small bowel tumors was 68.9% (42/61), 75.3% (70/93), and 78.3% (18/23), respectively. Therapeutic plans were changed due to the DBE results in 64.2% of patients with small bowel tumors. CONCLUSIONS: Approximately one-sixth of patients who received DBE had small bowel tumors, and the most common reason for DBE among patients with small bowel tumors was OGIB. DBE is a useful method for the confirmative diagnosis of small bowel tumors and has a good clinical impact on therapeutic plans and short-term clinical results.

Endovascular management for isolated spontaneous dissection of the superior mesenteric artery: report of two cases and literature review.

The clinical course and treatment strategies of isolated superior mesenteric artery (SMA) dissection have not been fully investigated. Two cases of uncontrolled abdominal pain caused by isolated SMA dissection were successfully treated with percutaneous endovascular stent placement. At follow-up 6 months later, computed tomography confirmed that the lesions had stabilized. The patients remained symptom free at 14- and 13-month follow-up, respectively. The present report describes these two cases of isolated SMA dissection treated successfully with percutaneous endovascular stent placement, along with a review of the related literature.

Diagnostic utility of anti-Saccharomyces cerevisiae antibody (ASCA) and Interferon-γ assay in the differential diagnosis of Crohn's disease and intestinal tuberculosis.

BACKGROUND: Differential diagnosis of Crohn's disease (CD) from intestinal tuberculosis (ITB) is challenging. Anti-Saccharomyces cerevisiae antibody (ASCA) is a specific serological marker for CD and INF-gamma assay (QuantiFERON-TB gold test, QFT) is a good supplementary diagnostic tool for ITB. We evaluated the clinical usefulness of ASCA and QFT for differential diagnosis of CD from ITB in Korean adults. METHODS: A total of 147 patients suspected to have ITB or CD were prospectively enrolled from 13 hospitals. ASCA IgG and IgA serum titers were measured by ELISA, and the QFT test was also performed. RESULTS: Thirty-two of 72 (44.4%) patients with CD were ASCA positive (titer >25U) compared to 10 of 75 ITB patients (13.3%) and 3 of 20 healthy controls (15%) (p<0.01). The QFT test was positive in 7 patients with CD (9.7%) and 50 patients with ITB (66.6%) (p<0.01). In cases which ASCA positive/QFT negative, the sensitivity, specificity, positive predictive value, and negative predictive value for the diagnosis of CD were 44.4%, 96.0%, 91.4%, and 64.3%, respectively. CONCLUSION: ASCA is a useful diagnostic tool for CD in Korea, where ITB is prevalent. In particular, when ASCA is combined with QFT, effective differential diagnosis of CD from ITB is possible.

Rifampin-induced Pseudomembranous Colitis with Rectosigmoid Sparing.

Pseudomembranous colitis (PMC) is known to be associated with antibiotic treatment, but is not commonly related to antitubercular (anti-TB) agent, rifampin. PMC is frequently localized to rectum and sigmoid colon, which can be diagnosed with sigmoidoscopy. We report a case of rifampin-induced PMC with rectosigmoid sparing in a pulmonary tuberculosis patient. An 81-year-old man using anti-TB agents was admitted with a 30-day history of severe diarrhea and general weakness. On colonoscopy, nonspecific findings such as mucosal edema and erosion were found in sigmoid colon, whereas multiple yellowish plaques were confined to cecal mucosa only. Biopsy specimen of the cecum was compatible with PMC. Metronidazole was started orally, and the anti-TB medications excluding rifampin were readministerred. His symptoms remarkably improved within a few days without recurrence. Awareness of rectosigmoid sparing PMC in patients who develop diarrhea during anti-TB treatment should encourage early total colonoscopy.