Background The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged as a dramatic challenge for all healthcare systems worldwide. This outbreak immediately affected gastroenterologists as well as global physicians worldwide because COVID-19 can be associated with not only triggering respiratory inflammation but also gastrointestinal (GI) inflammation based on the mechanism by which SARS-CoV-2 enters cells via its receptor the angiotensin-converting enzyme 2, which is expressed on GI cells. However, the comorbidity spectrum of digestive system in patients with COVID-19 remains unknown. Because the inflammatory bowel disease (IBD) management involves treating uncontrolled inflammation with immune-based therapies, physicians, and patients have great concern about whether IBD patients are more susceptible to SARS-CoV-2 infection and have worsened disease courses. Summary It is necessary to precisely ascertain the risk of SARS-CoV-2 infection and the COVID-19 severity in IBD patients and to acknowledge the IBD management during the COVID-19 pandemic with clinically reliable information from COVID-19 cohorts and IBD experts' opinions. In this review, we highlight clinical questions regarding IBD management during the COVID-19 pandemic and make comments corresponding to each question based on recent publications. Key Messages We propose that there is (1) no evidence that IBD itself increases the risk of SARS-CoV-2 infection, (2) to basically prioritize the control of disease activity of IBD, (3) no need for physicians to suddenly discontinue immunomodulatory or biologic therapy in patients with quiescent IBD, and (4) a need for careful observation of elderly (>60 years old) and IBD patients receiving corticosteroid treatment during the COVID-19 pandemic.

Objective There are no reports on whether or not trainees can safely carry out endoscopic procedures for the removal of common bile duct (CBD) stones. The aim of this study was to investigate the efficacy and safety of endoscopic treatments for CBD stones by trainees. Methods Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 1,016 consecutive patients at our institution during the 6-year study period. The endoscopically treated patients with CBD stones were included in this study. Physicians who had experienced ≥300 ERCP procedures were defined as experts, while those who had experienced <300 procedures were defined as trainees. The trainees were replaced by an expert when they could not achieve the established criteria. Patients were divided into the following three groups to retrospectively examine the patients' backgrounds, details of endoscopic treatments, and intra-/post-operative complications: Group A, completed by trainees under supervision of an expert; B, treated by an expert who switched in for a trainee in the middle of the procedure; and C, completed by an expert. Results A total of 325 patients with CBD stones underwent endoscopic treatments. The number included in Groups A, B, and C was 176, 102, and 47, respectively. The bile duct catheter insertion successes rates for Groups A, B, and C were 99.0%, 97.1%, and 100% (p=0.09), and the complete stone removal rates were 94.2%, 94.8%, and 100%, respectively (p=0.07), showing no significant difference among the three groups. Furthermore, the frequency of intra-/post-operative complications was not significantly different among the three groups (p=0.48, p=0.12, respectively). Conclusion This study showed that trainees could safely perform endoscopic procedures in accordance with our facility's criteria during ERCP.

On DEAE cellulose column chromatography, alpha-L-iduronidase in cultured skin fibroblasts was resolved into two distinct components, forms A and B. They had similar Km values for 4-methylumbelliferyl-alpha-L-iduronide, but differed in pH optima and thermal stability. Form B was more heat-stable than form A. Residual alpha-L-iduronidase activity in Hurler fibroblasts was heat-stable, while that in Scheie fibroblasts was heat-labile, and moreover, that in Hurler-Scheie compound fibroblasts lay intermediate between Hurler and Scheie syndromes. These findings demonstrated that Hurler syndrome, Scheie syndrome and Hurler-Scheie compound were enzymatically distinguishable.

A prenatal diagnosis of Hurler's syndrome was made in a pregnancy at risk in a family with two affected children. The fetus was diagnosed as having Hurler's syndrome on the basis of a deficiency of alpha-L-iduronidase in the cultured amniotic cells. The glycosaminoglycans (GAG) content in the supernatant of the amniotic fluid was increased about 1.5 fold compared with that in the control, and increases of heparan sulfate and dermatan sulfate were observed on electrophoresis. The diagnosis could be confirmed by the deficiencies of alpha-L-iduronidase in the liver and brain from the affected fetus. GAG content in the liver from the affected fetus was increased approximately 10 fold as compared with that in the control fetal liver, and most of the GAG were degraded. The GAG content was observed to be increased two fold in the brain, and dermatan sulfate, which was not detected in normal fetal brain, was identified. beta-Galactosidase activities in the affected liver and brain were decreased to 30-50% of the control, and an altered hexosaminidase A was also observed in the liver.

A severely mentally retarded infant with congenital lactic acidosis due to pyruvate carboxylase deficiency is reported. The patient suffered from vomiting and convulsions soon after birth and developed severe mental and motor retardation at 3 months of age. The persistent elevation of pyruvate and lactate in both blood and cerebrospinal fluid and hyperalanaemia suggested an impairment of pyruvate oxidation. The enzyme activities of pyruvate carboxylase in both liver tissues and cultured skin fibroblasts of the patient revealed values of about 5% of controls. However, pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase activities in liver tissues were within normal limits. The patient had no response to administration of large doses of thiamine, lipoic acid and biotin, clinically and biochemically. A prenatal diagnosis was performed in the second pregnancy and the pyruvate carboxylase activities of the cultured amniotic fluid cells obtained by amniocentesis were within normal limits.