Background: The distal esophagus harbors a complex bacterial population. We hypothesized that a better understanding of bacterial communities in the esophagus would facilitate understanding of the role of bacteria in esophageal disease. Here, we investigated bacterial composition in the distal esophagus in subjects with a normal esophagus, reflux esophagitis, and Barrett’s esophagus. Methods: Two biopsy specimens were obtained from the distal esophagus at 1 cm above the gastroesophageal junction under endoscopic examination in 18 patients (6 each with normal esophagus, reflux esophagitis, and Barrett’s esophagus) and used for histological examination and DNA extraction. Fragments of 16S rDNA genes were amplified by PCR using general bacterial primers, and bacterial populations were examined. A third biopsy specimen was taken from the patients with Barrett’s esophagus to histologically confirm the replacement of squamous epithelium with columnar epithelium in the distal esophagus. Results: Endoscopic diagnoses of normal esophagus, esophagitis, and Barrett’s esophagus were confirmed by histological findings. The total amount of bacterial DNA detected did not significantly differ among groups (p > 0.1). On average, each of the 18 subjects yielded about 350 clones, of which 40 were randomly picked and sequenced. Analysis of 147 16S rDNA sequences from 240 clones of 6 subjects with normal esophagus yielded four phyla, Proteobacteria (49%), Firmicutes (40%), Bacteroidetes (8%), and Actinobacteria (3%). Similar analysis of 139 16S rDNA sequences from 240 clones of 6 patients with reflux esophagitis yielded 6 phyla, Proteobacteria (43%), Firmicutes (33%), Bacteroidetes (10%), Fusobacteria (10%), Actinobacteria (2%), and TM7 (2%). while that of 138 16S rDNA sequences from 240 clones of 6 cases of Barrett’s esophagus yielded 5 phyla, Firmicutes (55%), Proteobacteria (20%), Bacteroidetes (14%), Fusobacteria (9%), and Actinobacteria (2%). Thus, microbial communities differed among patients with a normal esophagus, reflux esophagitis and Barrett’s esophagus. Conclusions: Esophageal bacterial composition differs under conditions of normal esophagus, reflux esophagitis, and Barrett’s esophagus. Diverse bacterial communities may be associated with esophageal disease.

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) typically arises from sites such as the stomach, where there is no organized lymphoid tissue. Close associations between Helicobacter pylori and gastric MALT lymphoma or Campylobacter jejuni and immunoproliferative small intestinal disease (IPSID) have been established. A subset of tumors is associated with chromosomal rearrangement and/or genetic alterations. This disease often presents as localized disease, requiring diverse treatment approaches, from antibiotic therapy to radiotherapy and immunochemotherapy. Eradication therapy for H. pylori effectively cures gastric MALT lymphoma in most patients. However, treatment strategies for H. pylori-negative gastric MALT lymphoma are still challenging. In addition, the effectiveness of antibiotic therapy has been controversial in intestinal MALT lymphoma, except for IPSID. Endoscopic treatment has been noted to usually achieve complete remission in endoscopically resectable colorectal MALT lymphoma with localized disease. MALT lymphoma has been excluded from post-transplant lymphoproliferative disorders with the exception of Epstein–Barr virus (EBV)-positive marginal zone lymphoma (MZL). We also describe the expanding spectrum of EBV-negative MZL and a close association of the disease with the gastrointestinal tract.

Background and Aims. Several studies have shown the benefits of endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) using a Franseen needle for histological assessment. However, studies focusing on pancreatic diseases are limited and the safety of this method has not been well assessed. We aimed to assess the current status and issues of EUS-FNB in the diagnosis of pancreatic diseases. Materials and Methods. We retrospectively reviewed 87 consecutive EUS-FNB specimens using either a 22-gauge Franseen needle (Group A, N = 51) or a conventional 22-gauge fine-needle aspiration needle (Group B, N = 36) for pancreatic diseases, and the diagnostic accuracy and safety were compared. Final diagnoses were obtained based on surgical pathology or a minimum six-month clinical follow-up. Results. Although the diagnostic accuracy for malignancy was 96.1% in Group A versus 88.9% in Group B, with no statistically significant difference (P = 0.19), the median sample area was significantly larger in Group A (4.07 versus 1.31mm², P < 0.0001). There were no differences between the two needles in the locations from which the specimens were obtained. Adverse events occurred in one case (2%) in Group A (mild pancreatitis) and none in Group B with no statistical significance (P = 0.586). Although there was no case of bleeding defined as adverse events, 2 cases in Group A showed active bleeding during the procedure with increase in the echo-free space, which required CT scanning to rule out extravasation. Eventually, the bleeding stopped spontaneously. Conclusions. Given its guaranteed ability to obtain core specimens and comparable safety, and although the risk of bleeding should be kept in mind, EUS-FNB using a Franseen needle is likely to become a standard procedure for obtaining pancreatic tissue in the near future.