Yann Revillon

Neonatal short bowel syndrome

In this retrospective study the management of infants who had undergone resection of more than 50% of the small bowel as newborn infants between 1970 and 1988 was analyzed to define prognostic factors. Small bowel resections were performed for atresia (36 cases), volvulus (22 cases), gastroschisis (10 cases), necrotizing enterocolitis (11 cases), and other disorders (8 cases). Patients were classified into two groups depending on the length of residual small bowel: group 1 (n = 35) had less than 40 cm of small bowel and group 2 (n = 51) had 40 to 80 cm of residual small bowel. Patients in group 2 had significantly better survival rates than those in group 1 (92.0% vs 66.6%; p less than 0.001). The patients in group 1 who were born after 1980, when home parenteral nutrition was introduced, had better survival rates than those who were treated before 1980 (95.0% vs 65.0%; p less than 0.01). The time required for acquisition of intestinal adaptation depended on the intestinal length (average, 27.3 months for group 1 and 14 months for group 2; p less than 0.01) and on the presence or absence of the ileocecal valve. Parenteral or supportive enteral nutrition, or both, ensured normal growth in both groups. We conclude that more than 90% of infants now survive after extensive small bowel resection with parenteral nutrition and that the remaining small intestine will adapt with time. Home-based parenteral nutrition allowed children to be treated in the best psychosocial environment.

Loss-of-function of MYO5B is the main cause of microvillus inclusion disease: 15 novel mutations and a CaCo-2 RNAi cell model†

Autosomal recessive microvillus inclusion disease (MVID) is characterized by an intractable diarrhea starting within the first few weeks of life. The hallmarks of MVID are a lack of microvilli on the surface of villous enterocytes, occurrence of intracellular vacuoles lined by microvilli (microvillus inclusions), and the cytoplasmic accumulation of periodic acid‐Schiff (PAS)‐positive vesicles in enterocytes. Recently, we identified mutations in MYO5B, encoding the unconventional type Vb myosin motor protein, in a first cohort of nine MVID patients. In this study, we identified 15 novel nonsense and missense mutations in MYO5B in 11 unrelated MVID patients. Fluorescence microscopy, Western blotting, and electron microscopy were applied to analyze the effects of MYO5B siRNA knock‐down in polarized, brush border possessing CaCo‐2 cells. Loss of surface microvilli, increased formation of microvillus inclusions, and subapical enrichment of PAS‐positive endomembrane compartments were induced in polarized, filter‐grown CaCo‐2 cells, following MYO5B knock‐down. Our data indicate that MYO5B mutations are a major cause of microvillus inclusion disease and that MYO5B knock‐down recapitulates most of the cellular phenotype in vitro, thus independently showing loss of MYO5B function as the cause of microvillus inclusion disease. Hum Mutat 31:1–8, 2010.

Role of embolisation in the treatment of bronchopulmonary sequestration.

Background. Sequestrations represent bronchopulmonary malformations that are increasingly diagnosed antenatally. After birth, the therapeutic approach in asymptomatic children is debated, as some may spontaneously regress.¶Objective. To evaluate the efficacy of embolisation of the feeding systemic artery in the treatment of bronchopulmonary sequestration.¶Materials and methods. Sixteen children with bronchopulmonary sequestration were treated by endovascular embolisation of the feeding systemic artery.¶Results. Ten patients were considered cured by embolisation alone. One patient was operated on after unsuccessful embolisation, three had partial regression of the lung mass and two are still under follow-up.¶Conclusions. Our experience indicates that bronchopulmonary sequestrations in children can be treated by embolisation alone.

Thoracoscopic Treatment of Mediastinal Cysts in Children

BACKGROUND/PURPOSE The development of thoracoscopic surgery has made many procedures possible, including the treatment of mediastinal cysts in children. The authors report their experience with this procedure between 1992 and 1997. METHODS Surgery was performed on 22 children aged from 1 month to 9 years (median, 27 months), weighing 5 to 49 kg (median, 12.5 kg). Diagnosis was made by antenatal ultrasound scan in six cases (27%), with a chest x-ray performed for respiratory symptoms in 14 cases, and with a chest x-ray performed for positive tuberculin intradermoreaction in two cases. Decision to resect the cyst was determined by thoracoscopy in 21 of the 22 cases, and by open surgery in one case only (subcarinal compressive cyst with left lung distension and a mediastinal shift). RESULTS Eighteen of the 21 (86%) cases were treated successfully by thoracoscopy. In three cases of bronchogenic cysts, we performed an associated thoracotomy because the dissection was too difficult and dangerous. In three cases, a small part of a common wall between the cyst and the bronchus was not removed. The pathological diagnosis was bronchogenic cysts in 15 cases (71%), pleuropericardiat cysts in three cases (14%), esophageal duplication in two cases (10%), and cystic hygroma in one case (5%). Two postoperative complications were observed: one esophageal wound and a case of recurrent pneumothorax after chest tube removal. Patients were discharged after 2 to 11 days (median, 3 days). Follow-up was uneventful. CONCLUSIONS Treatment of mediastinal cyst by thoracoscopy is feasible in most cases. Compressive cysts with lung distension and mediastinal shift remain a contraindication. If the cysts have a common wall with the bronchus or esophagus, or if they are subcarinal, the dissection may be difficult and dangerous, and thoracotomy may be preferable.

Long term results of liver-kidney transplantation in children with primary hyperoxaluria.

Abstract. From 1990 to 2000, we performed eight liver-kidney transplants in eight children, aged 1–16 years, with end-stage renal failure (ESRF) due to primary hyperoxaluria (PH1). The duration of dialysis before transplantation ranged from 2 to 42 months (mean 14 months) and was <1 year in four patients. Only the first patient underwent postoperative hemodialysis; in the other five, we chose to induce maximal diuresis from the first hours with intravenous and intragastric hyperhydration (≥3 l/m2 per day). High water intake with nocturnal tube hydration was maintained for 6 months to 5 years, as long as oxaluria exceeded 0.5 mmol/day. A quadruple sequential immunosuppressive regimen was used. Two patients died during liver graft surgery. The other six patients are alive and well, with a mean follow-up of 7.4 years (range 5–11 years). Patient and graft survival is 75% at 5 years. At latest follow-up, liver tests were normal in all six patients; creatinine clearance ranged from 55 to 95 ml/min per 1.73 m2 (mean=74). Oxaluria was lower than 0.4 mmol/day in all patients (mean=0.22). The six patients underwent 15 renal biopsies, 1–11 years after transplantation. Chronic transplant nephropathy was present in four patients and mild cyclosporin nephrotoxicity in another. No oxalate crystals were seen and repeat ultrasonography has been consistently normal in all patients. The three patients with bone oxalosis showed progressive complete healing of bone lesions. All six children or adolescents now live a normal life. From this series, we conclude that early combined liver-kidney transplantation is the treatment of choice for children with ESRF due to primary hyperoxaluria.

Spectrum of HLXB9 Gene Mutations in Currarino Syndrome and Genotype-Phenotype Correlation

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. Hum Mutat 29(7), 903–910, 2008.

Congenital cystic adenomatoid malformation of the lung: Prenatal management and prognosis☆

Thirty-two cases of congenital cystic adenomatoid malformation of the lung diagnosed antenatally are reported. Antenatal diagnosis has made it possible to document the progress of the condition in utero and the postnatal prognosis. It has been possible to advise on termination and intrauterine intervention, to counsel the parents, and to plan arrangements for delivery and postnatal care among obstetricians, neonatologists, and pediatric surgeons. According to Stockers classification there were 12 cases of type I, 15 of type II, and 5 of type III. Five pregnancies were terminated. Antenatal drainage of a cyst was performed in four patients with two survivors. Thirteen babies showed relative regression of the cyst as pregnancy progressed. After delivery the extent of the cystic malformation was assessed by chest x-rays and computed tomography scanning in 25 and angiography in 6. Treatment consisted of observation in 4, embolization in 2, operation as an emergency in 3, and electively around 4 months in 15.

Prenatal diagnosis of pulmonary sequestration using three-dimensional power Doppler ultrasound

To investigate the contribution of three‐dimensional power Doppler ultrasound to the prenatal diagnosis of pulmonary sequestration.

Assessment and outcome of children with intestinal failure referred for intestinal transplantation

BACKGROUND & AIMS Chronic intestinal failure (CIF) requires long term parenteral nutrition (PN) and, in some patients, intestinal transplantation (ITx). Indications and timing for ITx remain poorly defined. In the present study we aimed to analyze causes and outcome of children with CIF. METHODS 118 consecutive patients referred to our institution were assessed by a multidisciplinary team and four different categories were defined retrospectively based on their clinical course: Group 1: patients with reversible intestinal failure; group 2: patients unsuitable for ITx, group 3: patients listed for ITx; group 4: patients stable under PN. Analysis involved comparison between groups for nutritional status, central venous catheter (CVC) related complications, liver disease, and outcome after transplantation by using non parametric tests, Mann-Whitney tests, Kruskal-Wallis, Wilcoxon signed rank tests and chi square distribution for percentage. RESULTS 118 children (72 boys) with a median age of 15 months at referral (2 months-16 years) were assessed. Etiology of IF was short bowel syndrome [n = 47], intractable diarrhea of infancy [n = 37], total intestinal aganglionosis [n = 18], and chronic intestinal pseudoobstruction [n = 17]. Most patients (89.8%) were totally PN dependent, with 48 children (40.7%) on home-PN prior to admission. Nutritional status was poor with a median body weight at -1.5 z-score (ranges: -5 to +2.5) and median length at -2.0 z-score (ranges: -5.5 to +2.3). The mean number of CVC inserted per patient was 5.2 (range 1-20) and the mean number of CRS per patient was 5.5 (median: 5; range 0-12) Fifty-five patients (46.6%) had thrombosis of ≥2 main venous axis. At admission 34.7% of patients had elevated bilirubin (≥50 μmol/l), and 19.5% had platelets <100,000/ml, and 15% had both. Liver biopsy performed in 79 children was normal (n = 4), or showed F1 or F2 fibrosis (n = 29), bridging fibrosis F3 (n = 20), or cirrhosis (n = 26). Group 1 included 10 children finally weaned from PN (7-years survival: 100%). Group 2 included 12 children with severe liver disease and associated disorders unsuitable for transplantation (7-years survival: 16.6%). Group 3 included 66 patients (56%) who were listed for small bowel or liver-small bowel transplantation, 62/66 have been transplanted (7 years survival: 74.6%). Factors influencing outcome after liver-ITx were body weight (p < .004), length (p < .001), pre-Tx bilirubin plasma level (p < .001) and thrombosis (p < .01) for isolated ITx, Group 4 included 30 children (25.4%) with irreversible IF considered as potential candidates for isolated ITx. Four children were lost from follow up and 3 died within 2 years (survival 88.5%). Among potential candidates, the following parameters improved significantly during the first 12 months of follow up: Body weight (p.0001), length (p < .0001) and bilirubin (p < .0001). CONCLUSIONS many patients had a poor nutritional status with severe complications especially liver disease. PN related complications were the most relevant indication for ITx, but also a negative predictor for outcome. Early patient referral for Tx-assessment might help to identify and separate children with irreversible IF from children with transient IF or uncomplicated long-term PN, allowing to adapt a patient-based treatment strategy including or not ITx.

Prenatal management of congenital cystic adenomatoid malformation of the lung

In utero evolution and postnatal outcome were studied for 18 cases of congenital adenomatoid malformation (CAM) diagnosed by prenatal ultrasound. Five were macrocystic CAM, 9 were microcystic, and 4 were homogeneously hyperechogenic. Three fetuses presented with hydrops. Pulmonary amniotic shunting was performed in 3 patients. Outcome was the following: 4 were aborted, 1 died neonatally, and 13 survived. Four of these infants required no surgery in the neonatal or postneonatal period. In three of these, the size of the mass had decreased spontaneously in utero. Outcome did not appear to be related to the anatomic type of CAM nor to the presence of moderate polyhydramnios, but was related to the degree of mediastinal compression and to the existence of hydrops. A clearer understanding of the natural evolution of CAM is useful to determine the indications for in utero therapy.