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Biomedical subjects

Y Revillon

Publications and source records attributed to Y Revillon.

At least 19 recordsLinked to original sources

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

OBJECTIVE: To investigate the contribution of three-dimensional power Doppler ultrasound to the prenatal diagnosis of pulmonary sequestration. METHODS: Prenatal three-dimensional power Doppler ultrasound was used to screen for an abnormal pulmonary blood supply in eight fetuses with hyperechogenic lung lesions and to image the pulmonary blood supply in 50 normal controls. A comparison was made with postnatal findings. RESULTS: Postnatally the eight pulmonary lesions were found to be an isolated pulmonary sequestration (n = 3), a microcystic congenital adenomatoid malformation (n = 4), and a mixed (macrocystic and microcystic) congenital adenomatoid malformation (n = 1). Prenatal three-dimensional power Doppler ultrasound demonstrated an abnormal blood supply in all cases of pulmonary sequestration and in none of the other cases. Among the three cases that turned out to be pulmonary sequestrations, conventional two-dimensional ultrasound failed to identify the feeding vessel in one case and identified it at a later stage of gestation than did three-dimensional power Doppler in the other two. CONCLUSION: Prenatal three-dimensional power Doppler ultrasound may be useful in identifying the feeding vessel and thus establishing the diagnosis of pulmonary sequestration in the presence of a hyperechogenic pulmonary lesion, allowing its differentiation from congenital cystic adenomatoid malformation.

Adolescent↗

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

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 (> or =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.

Adolescent↗

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.

Angiography↗

Allogeneic fetal small bowel graft in pigs treated with cyclosporin A.

BACKGROUND: The functional integrity of transplanted fetal intestine was proven in rodents. The authors examined the morphology and development of intraperitoneally transplanted fetal intestine under cyclosporin A (CsA) monotherapy in a large mammal. METHODS: Allogeneic fetal intestinal grafts were transplanted intraperitoneally in pigs. The graft was wrapped in omentum. Thirteen recipients received grafts harvested at 60 days of gestation and 5 at 105 days of gestation. All recipients received 25 mg/kg/d CsA. CsA blood levels were measured at the end of the study. The development of the grafts was assessed by inspection and histology studying revascularization, maturation, and immune rejection. RESULTS: All grafts developed neovascularization. The intestinal wall in the 105-day-old group was thick enough to lead to complete mucosal destruction, whereas the 60-day-old group showed viable mucosa. All grafts induced an immune rejection. This immune response was correlated with the CsA blood level. The graft was destroyed within 15 days when CsA trough level was below 70 ng/mL, had a subacute rejection with villi atrophy when CsA trough level ranged from 70 to 150 ng/mL, and had a good appearance in spite of mild blunting of villi when CsA trough level was over 150 ng/mL. CONCLUSION: Allogeneic fetal intestinal transplantation from 60-day-old embryos in pig achieved successful graft.

Animals↗

Inflammatory pseudotumor of the liver: a rare benign tumor mimicking a malignancy.

We describe a 9-month-old boy in whom a hepatic tumor called angioma was diagnosed on ultrasonography, performed for abdominal pain. He was asymptomatic until 9 months later, when he presented with weight loss, jaundice, and a hard tumor in the left liver lobe. Radiological examination showed a calcified and heterogeneous tumor, amputation of the left portal vein, and dilatation of bile ducts, strongly suggesting malignancy. However, liver biopsy showed the typical findings of inflammatory pseudotumor, which are myofibroblastic cells and perivascular plasmocytes in a dense collagenous stroma. The tumor was surgically removed without local recurrence with a 2-year follow-up. Inflammatory pseudotumor in childhood is more common in the lung and elsewhere is often mistaken for a slowly growing cancer. This case points out the difficulties in the radiological evaluation of liver tumors in childhood and the importance of the histological differentiation of this lesion from malignancy before laparotomy for adequate indication of the treatment, which includes no medical treatment and surgery as conservative as possible.

Granuloma, Plasma Cell↗

Liver transplantation in urea cycle disorders.

We report here our experience in the long-term management of 28 patients with citrullinaemia, 13 patients with carbamoyl phosphate synthase deficiency and 15 patients with argininosuccinic aciduria. In addition, we report a national French survey of 119 patients with ornithine transcarbamylase (OTC) deficiency enzymatically characterized in our laboratory. We also include in this report four personal patients (two with OTC and two with citrullinaemia) who were liver transplanted, and one OTC patient from the National French survey. Although this retrospective series is not really representative of the modern treatment combining low protein diet and arginine, sodium benzoate and sodium phenylbutyrate, it is obvious that the long-term outcome of all urea cycle disorders remains very guarded. We highlight the severity of the neonatal forms of such disorders, and mostly for OTC-deficient males. According to this evidence, our policy is not to treat such severely affected patients in the neonatal period who die anyway spontaneously within 2 to 3 days. At the present time, we only have three patients with neonatal citrullinaemia, aged 1, 6 and 10 years respectively, who are still doing well. One of them has been successfully liver transplanted at 5 years. Another transplanted patient died in the post-surgical phase. We emphasize the unexpected severity of argininosuccinic aciduria in which there is no one patient doing well. This is a rather surprising finding as this disorder is easy to manage and rarely presents with recurrent attacks of hyperammonaemia when it is treated by arginine supplementation. This consideration would suggest to extend the indication of orthotopic liver transplantation in this disorder. Finally, the most difficult indication is in the late onset symptomatic female OTC group. In this last group, despite a significant residual activity due to heterozygote status, even with a variable lyonisation, only seven girls are still mentally and neurologically normal. Interestingly, three of these seven were liver-transplanted before the constitution of irreversible neurological damage. These three girls and their family declare their well-being, their feeling to be cured and enjoy their normal life.

Amino Acid Metabolism, Inborn Errors↗

Liver transplantation in propionic acidaemia.

Despite the improvement in dietary therapy during the past 20 years, the overall outcome of severe forms of propionic acidaemia (PA) remains often disappointing. Good results can be obtained at a very high price in terms of medical attention, family burden and high cost. In most early onset forms of PA, the intake of natural protein must be rigidly restricted to 8-12 g/day for the first 3 years of life, and then slowly increased to 15-20 g/day by the age of 6-8 years. Supplementation with a precursor-free aminoacid mixture to provide 1.5 g/kg protein per day is generally recommended, although remains controversial. From the age of 1 year onward, these children are often severely anorectic and most of the diet must be delivered by nocturnal gastric drip feeding or gastrostomy. Metronidazole is very effective in reducing the excretion of propionate metabolites derived from the gut. L-carnitine (50 to 100 mg/kg) is systematically given to promote propionylcarnitine synthesis and excretion. We report here a retrospective study of 33 patients with PA diagnosed during the last 20 years in our hospital. Of them, 2 have been liver transplanted. In these two patients who presented frequent severe and unexpected metabolic decompensations despite good compliance with the dietary therapy, orthotopic liver transplantation (OLT) was done at 7 and 9 years respectively. One child died 15 months after transplantation due to a severe lymphoproliferative disorder; the other child now aged 13.5 years is doing well. Despite a persistent methylcitrate excretion, she is under normal moderate daily protein intake (40-50 g/day) and still on carnitine supplementation. Interestingly, another patient who filled the criteria for OLT (very frequent and severe decompensations leading to frequent admissions to the intensive care unit despite excellent dietary management) was also placed on the list for OLT. From the time he was registered onward, he experienced no further episodes of metabolic decompensation, there was almost no interruption in his daily intake and he gained height and weight and developed well. He was finally removed from the list and is still doing very well 2 years thereafter. Correction of propionylCoA carboxylase deficiency restricted to hepatic tissues seems to induce a change towards clinical normalisation and a milder biochemical phenotype. Liver transplanted PA patients still require slight protein restriction and carnitine treatment. We consider that at the moment OLT should only be performed in severe forms of PA, mostly characterised by frequent and unexpected episodes of metabolic decompensation despite good dietary therapy. However, a strict appreciation of these criteria is difficult. A more generalised indication for OLT in PA will require more information about the long-term outcome of transplanted patients. We should also await other alternatives like auxiliary partial OLT from living donors or transplantation of isolated allogenic hepatocytes, genetically modified or not.

Adolescent↗

Treatment of progressive familial intrahepatic cholestasis: liver transplantation or partial external biliary diversion.

Progressive intrahepatic familial cholestasis (PFIC), previously called Byler's disease, is a syndrome in which children develop severe cholestasis progressing to biliary cirrhosis and chronic liver failure, usually during the first decade of life. Clinical features include jaundice, hepatomegaly, splenomegaly, growth retardation and severe pruritus. Laboratory tests demonstrate elevated bilirubin and bile acids, without an increase in serum gamma-glutamyl-transpeptidase or cholesterol. This study was performed to evaluate our experience with medical therapy as well as two types of surgical treatment used in children with PFIC, particularly partial external biliary diversion (PEBD) as an alternative method of therapy to liver transplantation (OLTx). Between 1979 and 1998 we have treated 46 children with PFIC (27 boys and 19 girls), aged 10 months to 19 yr (at the time of this study). Medical treatment with ursodeoxycholic (UDCA) was used in 39 patients for the period between 6 and 82 months. PEBD (cholecysto-jejuno-cutaneostomy) was performed in 16 patients, OLTx in eight children (including one after unsuccessful PEBD). Retrospective analysis of the clinical course and selected laboratory tests (bilirubin, ASPAT, ALAT, bile acids), and histopathological examinations were performed. Results of treatment were assessed by means of influence of the type of treatment on clinical symptoms, laboratory tests, progress of liver cirrhosis and hepatic failure, as well as physical development and survival. Medical therapy was effective in the long term in four (10%) of the patients resulting in clinical and biochemical normalization. Both surgical methods of therapy of PFIC, PEBD and OLTx, resulted in an 80% success rate and therefore should be used as complementary therapies. In patients before established liver cirrhosis, PEBD should be the first choice of treatment. Patients presenting with cirrhosis or after ineffective PEBD should qualify for OLTx. With this strategy most children with PIFC can be cured.

Adolescent↗

[Can intestinal transplantation constitute treatment for intestinal failure?].

The management of patients with intestinal failure has benefited from progress in parenteral nutrition (PN), especially home-based parental nutrition. Intestinal transplantation is now possible and in some conditions, constitutes the logical treatment option. Since 1985, more than 300 small-bowel grafts have been performed, involving the isolated small bowel with or without the colon (45%), the liver + small bowel (40%) or several organs (15%). 2/3 of recipients were under 20 years of age, and indications were short-bowel syndrome (64%), severe intractable diarrhea (13%), abdominal cancer (13%), or chronic intestinal pseudo-obstruction syndrome (8%). 51% of patients survived > 2 years after the graft. Patient and graft survival depends on the type of immunosuppression, i.e. Cyclosporine or FK 506. The results must be interpreted carefully as they represent the first experience in numerous centers using different immuno-suppressive protocols, without any randomization. The results from the largest of these centers more closely reflect the current situation and may exceed a 70% 2-year survival rate. Functional grafts lead to gastrointestinal autonomy (weaning of PN) while maintaining satisfactory nutritional status and normal growth in childhood. Intestinal transplantation is theoretically indicated for all patients permanently or persistently dependent on PN. However, as PN is generally well tolerated, even for long periods, each indication for transplantation must be carefully weighed up in terms of the iatrogenic risk and quality of life. When PN has reached its limits, especially those associated with vascular, infectious, hepatic or metabolic complications, intestinal transplantation must be undertaken. Transplantation of the small bowel alone remains the first option, as combined liver-small bowel grafting is only indicated in case of life-threatening progressive cirrhogenic liver disease.

Adolescent↗

[Study of sustained forces and the working space of endoscopic surgery instruments].

UNLABELLED: The instruments currently used in endoscopic surgery are limited by several factors, in particular their reduced working space. In order to develop instruments with manifold degrees of freedom (DOF), the elementary actions performed by the existing instruments must be defined. MATERIAL AND METHODS: We have broken down into elementary movements the actions performed by the currently used instruments and analyzed them by measuring the strain on the instruments and on their working volume. The elementary actions were performed in vitro (Pelvitrainer) on an animal model (pig) and also in the course of clinical practice. A total of 6,750 measurements were carried out for the following actions: grasping, cutting, dissecting, suturing and knotting. RESULTS: The largest working volumes were measured for the knotting and suturing actions (198 degrees in axial rotation and 69 degrees in lateral translation). The range of the working space was between 8 degrees and 52 degrees. Forces exerted on the instrument were between 0.5 and 12 Newton (N). Forces exerted on the headpoint were between 0.4 and 10.5 N whereas the friction forces were between 0.5 and 1.5 N. COMMENTS: By analyzing the elementary actions of endoscopic surgery, we were able to quantify the directions and dimensions of forces sustained by the instruments and were also able to measure the working volume involved when performing the main actions in endoscopic surgery. The results obtained provide a basis for the development of more sophisticated instruments.

Animals↗