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This lecture updates the pediatric surgeon on current indications, techniques, and results of intestinal transplantation in children with intestinal failure with reference to the Paris series., (Copyright © 2011. Published by Elsevier Inc.)

Currarino syndrome (CS) is a rare congenital malformation described in 1981 as the association of three main features: typical sacral malformation (sickle-shaped sacrum or total sacral agenesis below S2), hindgut anomaly, and presacral tumor. In addition to the triad, tethered cord and/or lipoma of the conus are also frequent and must be sought, as they may lead to severe complications if not treated. The HLXB9 gene, located at 7q36, is disease-causing. It encodes the HB9 transcription factor and interacts with DNA through a highly evolutionarily conserved homeodomain early in embryological development. Thus far, 43 different heterozygous mutations have been reported in patients fulfilling CS criteria. Mutation detection rate is about 50%, and reaches 90% in familial cases. Here, we report 23 novel mutations in 26 patients among a series of 50 index cases with CS, and review mutational reports published since the identification of the causative gene. Three cytogenetic anomalies encompassing the HLXB9 gene are described for the first time. Truncating mutations (frameshifts or nonsense mutations) represent 57% of those identified, suggesting that haploinsufficiency is the basis of CS. No obvious genotype-phenotype correlation can be drawn thus far. Genetic heterogeneity is suspected, since at least 19 of the 24 patients without HLXB9 gene mutation harbor subtle phenotypic variations.

Objective: Small bowel (SB) transplantation (Tx), long considered a rescue therapy for patients with intestinal failure, is now a well recognised alternative treatment strategy to parental nutrition (PN). In this retrospective study, we analysed graft functions in 31 children after SBTx with a follow-up of 2-18 years (median 7 years)., Patients: Twelve children had isolated SBTx, 19 had combined liver-SBTx and 17 received an additional colon graft. Growth, nutritional markers, stool balance studies, endoscopy and graft histology were recorded every 2-3 years post-Tx., Results: All children were weaned from PN after Tx and 26 children remained PN-free. Enteral nutrition was required for 14/31 (45%) patients at 2 years post-Tx. All children had high dietary energy intakes. The degree of steatorrhoea was fairly constant, with fat and energy absorption rates of 84-89%. Growth parameters revealed at transplantation a mean height Z-score of -1.17. After Tx, two-thirds of children had normal growth, whereas in one-third, Z-scores remained lower than -2, concomitant to a delayed puberty. Adult height was normal in 5/6. Endoscopy and histology analyses were normal in asymptomatic patients. Chronic rejection occurred only in non-compliant patients. Five intestinal grafts were removed 2.5-8 years post-Tx for acute or chronic rejection., Conclusions: This series indicates that long-term intestinal autonomy for up to 18 years is possible in the majority of patients after SBTx. Subnormal energy absorption and moderate steatorrhoea were often compensated for by hyperphagia, allowing normal growth and attainment of adult height. Long-term compliance is an important pre-requisite for long-term graft function.

Background: Although intestinal transplantation provides a unique situation of free access to the graft because of the presence of temporary enterostomas, evaluation of local immunosuppression is still an unresolved issue and may constitute one of the causes of grafting failure., Aims: To study in a rat model of allogeneic intestinal transplantation the expression of transcription factors involved in lymphocyte activation in situ in the graft and to identify factors reflecting the efficiency of drug immunosuppression., Methods: Intestinal transplantation was performed in a Brown Norway (RT1n-donors)-Lewis (RT1(l)-recipients) rat strain combination. The animals were treated with tacrolimus to induce tolerance or left untreated. Syngeneic intestinal grafts and intestine from donor rats with peritonitis were used as controls. NF-kappaBp65, p-c-Jun, interleukin 2 receptor (CD25), and major histocompatibility complex class II antigen (OX-6) expression was studied in graft biopsies on days 2 and 5 by immunohistochemistry., Results: On day 2, before the onset of histologic signs of rejection, the number of cells expressing NF-kappaBp65 in the pericryptic lamina propria was significantly higher in untreated recipients of allogeneic grafts than in the other groups (P = .009). NF-kappaBp65 expression then fell between days 2 and 5 (P = .009). Classic markers of T-cell activation (CD25 and OX-6) were expressed during rejection in the lamina propria and on crypt enterocytes, respectively. p-c-Jun expression did not differ among the 3 groups., Conclusion: NF-kappaBp65 expression in intestinal grafts is a precocious sign of local activation during rejection and could thus serve to optimize the management of immunosuppressive therapy.

Advances in immunosuppressive treatment as well as better monitoring and control of acute rejection have brought intestinal transplantation (ITx) into the realm of standard treatment for permanent intestinal failure. The results from the intestinal Transplant International Registry (www.intestinaltransplant.org) indicate that ITx is currently an acceptable clinical modality for selected patients with permanent intestinal failure. The goal of this short review is to deal with indications, clinical results and complications of ITx. Although it has been used in humans for the past two decades, very few data are available regarding graft function and its monitoring.

From November 1994 to November 1998, 20 children (2.5 to 14 years) received a jejunoileal graft alone (SBTx; n = 10) or in combination with the liver (SBLTx; n = 10 and/or the right colon (5 SBTx). Indications were intractable diarrhea of infancy (n = 8), short bowel syndrome (n = 6), extensive Hirschsprung disease (n = 4), and chronic intestinal pseudoobstruction (n = 2). Immunosuppression included tacrolimus, methylprednisolone, and azathioprine. Current follow-up ranges from 6 to 54 months. Five patients died (3 SBTx) within the first 2 months. Acute liver rejection occurred in 5 patients during the first 2 months. Sixteen episodes of intestinal rejection during the first 3 months in 11 patients (8 in 4 SBTx) were successfully treated in all but 3 by increasing tacrolimus dose and/or a 3-day methyprednisolone bolus or required antilymphoglobulins in 3 cases. Surgical complications occurred 8 times after SBLTx and 3 after SBTx. Infectious complications were more frequent in SBLTx recipients. Reversible Epstein-Barr virus-related posttransplant lymphoproliferative disease occurred in 3 recipients. Five presented cytomegalovirus infection. The SB graft was removed in 5 recipients (3 chronic rejection). All patients were started with oral and/or enteral feeding from the 7th postoperative day by using either normal food or protein hydrolysate diet. Currently, 10 of 11 children (8 SBLTx) achieved digestive autonomy after 5 to 30 weeks. All recipients gained weight; however, growth velocity remained reduced during the first 6 months because of the steroid therapy. Overall graft and patient survival is higher after SBLTx. Intestinal transplantation is indicated for patients with permanent intestinal failure. However, because parenteral nutrition is generally well tolerated, even for long periods, each indication for transplantation must be weighed carefully in terms of risk and quality of life.