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Development of potentially life-threatening enterocolitis is the most frequent complication in children with Hirschsprung disease (HSCR), even after definitive corrective surgery. Intestinal microbiota likely contribute to the etiology of enterocolitis, so the aim of this study was to compare the fecal bacterial and fungal communities of children who developed Hirschsprung-associated enterocolitis (HAEC) with HSCR patients who had never had enterocolitis. Eighteen Hirschsprung patients who had completed definitive surgery were enrolled: 9 had a history of HAEC and 9 did not. Fecal DNA was isolated and 16S and ITS-1 regions sequenced using Next Generation Sequencing and data analysis for species identification. The HAEC group bacterial composition showed a modest reduction in Firmicutes and Verrucomicrobia with increased Bacteroidetes and Proteobacteria compared with the HSCR group. In contrast, the fecal fungi composition of the HAEC group showed marked reduction in diversity with increased Candida sp., and reduced Malassezia and Saccharomyces sp. compared with the HSCR group. The most striking finding within the HAEC group is that the Candida genus segregated into “high burden” patients with 97.8% C. albicans and 2.2% C. tropicalis compared with “low burden” patients 26.8% C. albicans and 73% C. tropicalis. Interestingly even the low burden HAEC group had altered Candida community structure with just two species compared to more diverse Candida populations in the HSCR patients. This is the first study to identify Candida sp. as potentially playing a role in HAEC either as expanded commensal species as a consequence of enterocolitis (or treatment), or possibly as pathobioants contributing to the pathogenesis of HAEC. These findings suggest a dysbiosis in the gut microbial ecosystem of HAEC patients, such that there may be dominance of fungi and bacteria predisposing patients to development of HAEC.

Adult-congenital diaphragmatic hernia and chronic traumatic diaphragmatic hernia are amenable to laparoscopic repair. Although experience is still limited, laparoscopic repair appears safe and is associated with a shorter hospital stay.

Liver transplantation is the only clinically effective method of treating acute liver failure. However, wider application of this therapeutic modality is restricted primarily by shortage of donor organs. In the search for alternative methods of liver replacement therapy, investigators have focused on transplantation of normal allogeneic hepatocytes and on the development of liver support systems utilizing isolated hepatocytes. Since all human livers suitable for cell harvest are being used for transplantation, hepatocyte therapy using human tissue would require growing of cells in vitro. Unfortunately, although hepatocytes have tremendous capacity to proliferate in vivo, their ability to grow in culture is severely limited. Stromal cells from bone marrow and other blood-forming organs have been found to support hematopoiesis. In this paper, we show that bone marrow-derived stromal cells (BMSCs) enhance proliferation and support differentiation of rat hepatocytes in culture. Further, we demonstrate that in hepatocyte/BMSC co-cultures, clonal expansion of small hepatocytes (SH) is increased. Using semipermeable membrane cultures, we established that direct cell-cell contact is necessary for stimulation of cell proliferation. We also show that BMSCs which are in direct contact with hepatocytes and SH colonies express Jagged1. This suggests a potential role for Notch signaling in the observed effects. Finally, we present evidence that the expression and activity of liver specific transcription factors, CCAAT/enhancer binding proteins and liver specific key enzymes such as tryptophan 2,3-dioxygenase, are improved in hepatocyte/BMSC co-cultures. In conclusion, results of this study indicate that BMSCs could facilitate proliferation and differentiation of primary rat hepatocytes and their progenitors (SH) in vitro.

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Purpose Children with Hirschsprung disease (HD) who have a history of enterocolitis (HAEC) have a shift in colonic microbiota, many of which are necessary for short chain fatty acid (SCFA) production. As SCFAs play a critical role in colonic mucosal preservation, we hypothesized that fecal SCFA composition is altered in children with HAEC. Methods A multicenter study enrolled 18 HD children, abstracting for history of feeding, antibiotic/probiotic use, and enterocolitis symptoms. HAEC status was determined per Pastor et al. criteria (12). Fresh feces were collected for microbial community analysis via 16S sequencing as well as SCFA analysis by gas chromatography–mass spectrometry. Results Nine patients had a history of HAEC, and nine had never had HAEC. Fecal samples from HAEC children showed a 4-fold decline in total SCFA concentration vs. non-HAEC HD patients. We then compared the relative composition of individual SCFAs and found reduced acetate and increased butyrate in HAEC children. Finally, we measured relative abundance of SCFA-producing fecal microbiota. Interestingly, 10 of 12 butyrate-producing genera as well as 3 of 4 acetate-producing genera demonstrated multi-fold expansion. Conclusion Children with HAEC history have reduced fecal SCFAs and altered SCFA profile. These findings suggest a complex interplay between the colonic metabolome and changes in microbiota, which may influence the pathogenesis of HAEC.

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