Steffan Loff

Juvenile polyposis: massive gastric polyposis is more common in MADH4 mutation carriers than in BMPR1A mutation carriers

Abstract. Juvenile polyposis syndrome (JPS) is an autosomal dominant predisposition to multiple juvenile polyps in the gastrointestinal tract. Germline mutations in the MADH4 or BMPR1A genes have been found to be causative of the disease in a subset of JPS patients. So far, no genotype-phenotype correlation has been reported. We examined 29 patients with the clinical diagnosis of JPS for germline mutations in the MADH4 or BMPR1A genes and identified MADH4 mutations in seven (24%) and BMPR1A mutations in five patients (17%). A remarkable prevalence of massive gastric polyposis was observed in patients with MADH4 mutations when compared with patients with BMPR1A mutations or without identified mutations. This is the first genotype-phenotype correlation observed in JPS.

High proportion of large genomic deletions and a genotype–phenotype update in 80 unrelated families with juvenile polyposis syndrome

Background: In patients with juvenile polyposis syndrome (JPS) the frequency of large genomic deletions in the SMAD4 and BMPR1A genes was unknown. Methods: Mutation and phenotype analysis was used in 80 unrelated patients of whom 65 met the clinical criteria for JPS (typical JPS) and 15 were suspected to have JPS. Results: By direct sequencing of the two genes, point mutations were identified in 30 patients (46% of typical JPS). Using MLPA, large genomic deletions were found in 14% of all patients with typical JPS (six deletions in SMAD4 and three deletions in BMPR1A). Mutation analysis of the PTEN gene in the remaining 41 mutation negative cases uncovered a point mutation in two patients (5%). SMAD4 mutation carriers had a significantly higher frequency of gastric polyposis (73%) than did patients with BMPR1A mutations (8%) (p<0.001); all seven cases of gastric cancer occurred in families with SMAD4 mutations. SMAD4 mutation carriers with gastric polyps were significantly older at gastroscopy than those without (p<0.001). In 22% of the 23 unrelated SMAD4 mutation carriers, hereditary hemorrhagic telangiectasia (HHT) was also diagnosed clinically. The documented histologic findings encompassed a wide distribution of different polyp types, comparable with that described in hereditary mixed polyposis syndromes (HMPS). Conclusions: Screening for large deletions raised the mutation detection rate to 60% in the 65 patients with typical JPS. A strong genotype-phenotype correlation for gastric polyposis, gastric cancer, and HHT was identified, which should have implications for counselling and surveillance. Histopathological results in hamartomatous polyposis syndromes must be critically interpreted.

Frequent 4-bp deletion in exon 9 of the SMAD4/MADH4 gene in familial juvenile polyposis patients

Familial juvenile polyposis (FJP) is a hamartomatous polyposis syndrome characterized by the appearance of juvenile polyps in the gastrointestinal tract. Patients with this syndrome are at an increased risk for cancer of the colon, stomach, and pancreas. Recently, germline mutations in the SMAD4/DPC4 gene (official symbol MADH4) have been found in the majority of patients suffering from FJP. We have examined 11 unrelated patients with FJP for MADH4 germline mutations by direct sequencing of genomic DNA encompassing all 11 exons of the gene. Besides a novel mutation (959–960delAC at codon 277, exon 6) in one patient, we observed a 4‐bp deletion (1372–1375delACAG) in exon 9 in two unrelated patients. Examination with microsatellite markers flanking MADH4 supports an independent origin of the mutation in these two families. The same 4‐bp deletion in exon 9 has previously been described in three out of nine patients examined for MADH4 mutations. Our results combined with these previous data demonstrate that a unique 4‐bp deletion in exon 9 of MADH4 accounts for about 25% of all FJP cases and that other MADH4 mutations occur in an additional 15% of patients. Genes Chromosomes Cancer 25:403–406, 1999.

Congenital diaphragmatic hernia: a modern day approach.

Centralization of all complicated congenital diaphragmatic hernias (CDH) was organized in Germany from 1998, collecting 325 consecutive patients with striking increasing survival rates. This series report 244 patients from 2002 to 2007. Today, large defects are detected early in pregnancy by ultrasound and magnetic resonance imaging (MRI). In extracorporeal membrane oxygenation (ECMO) patients, prenatal lung head ratio (LHR) was 1.2 (median) at the 34th week of gestation or less than 25 ml lung tissue in MRI. This means that all patients below LHR of 1.4 should be transferred prenatally in a tertiary center. High risk group for survival was defined as LHR below 0.9, ie, 10 ml in MRI planimetry. Inborn patients show better results than outborns. In algorithm therapy, gentle ventilation plays an important role in preventing damage to the lung tissue and avoiding long term ventilation. When PaCO(2) was more than 75 mmHg, ventilation was changed to high frequency oscillatory ventilation (HFOV). Indication for ECMO was seen in preductal PaO(2) less than 50 mmHg over 2-4 h or less than 40 mmHg over 2 h. ECMO related risks included intracerebral bleeding (9%), intrapulmonary bleeding (14%), and convulsions (16%). Surgically, a longitudinal midline incision for exposure of the defect, the duodenal kinking, and probably for abdominal patching was perfect. A cone formed goretex patch provided more abdominal space and reduced abundant intrathoracical cavity. No drain was used. Postoperative complications were described. Overall survival in 244 consecutive patients was 86.5% for all patients born alive. All those who needed ECMO survived in 71%, underlining ECMO as a treatment of last choice. Follow-up for quality of life after CDH is described.

Hemarthrosis after trauma to the pediatric knee joint: what is the value of magnetic resonance imaging in the diagnostic algorithm?

In children, compulsory arthroscopy for hemarthrosis after knee trauma is not justified because ligamentous and meniscal damage is rare. In a prospective study, we analyzed the diagnostic value of radiography, magnetic resonance imaging (MRI), and arthroscopy in 51 patients up to 14 years of age with acute knee trauma. Plain radiography revealed 16 osseous lesions (5 metaphyseal, 3 patellar, 4 physeal fractures, 3 avulsions of the tibial spine, and 1 osseous ligamentous tear). In 29 patients, the cause of hemarthrosis remained unclear. All patients were evaluated by MRI. A diagnosis could be assigned to all 29 patients. MRI demonstrated lesions in 38 patients. In addition, the following lesions were discovered: 8 patellar dislocations, 13 bruises, 1 rupture of the anterior cruciate ligament, 1 osteochondritis dissecans, and 13 joint effusions. In 13 patients, MRI was followed by arthroscopy to confirm the diagnosis. Both, MRI and arthroscopy missed two osteochondral fractures. In addition, three chondral lesions were not picked up by MRI. MRI is a reliable tool for assessing the extent of knee lesions in children.

Kinetics of diethylhexyl-phthalate extraction From polyvinylchloride-infusion lines

BACKGROUND For infusion therapy, polyvinylchloride (PVC)-infusion lines are commonly used. In this study, we examined the temperature dependency and the dynamics of extraction in the time course of infusion. METHODS PVC-infusion lines used on the newborn ICU were perfused with a typical 24-hour fat infusion. We collected the perfused solution and measured the concentration of DEHP. This procedure was carried out at 27 degrees C and 33 degrees C. In another experiment, we examined the extraction rate in the time course of a 24-hour infusion. The infusion was collected every 4 hours. RESULTS We discovered that extraction of DEHP depends highly on the surrounding temperature. Whereas at 27 degrees C, the extraction of DEHP was 422.78 microg/mL, the leaching reached 540.78 microg/mL at 33 degrees C under otherwise identical conditions. This is important because the temperature on a newborn ICU is between 31 and 37 degrees C in an incubator. In the other experiment, we found out that the extraction rate rose from 25.44 microg/mL in the first 4 hours to 478.1 microg/mL after 24 hours. CONCLUSIONS The result of this study is that the actual daily load of DEHP for a 2-kg newborn is 30% higher than measured before. The rate of extraction is dependent on the time of contact between solution and tubing. If PVC-infusion systems are used, solutions should be as cold as possible, and infusion time should be as short as possible.

Use of Di(2-Ethylhexyl)Phthalate–Containing Infusion Systems Increases the Risk for Cholestasis

INTRODUCTION: Most polyvinylchloride infusion systems are plasticized with up to 60% of di(2-ethylhexyl)phthalate (DEHP). DEHP is easily extracted from the tubing by total parenteral nutrition (TPN) solutions and has been shown to have toxic effects on various organ systems including the liver in animals and humans. A role was postulated for DEHP in the development of hepatobiliary dysfunction in premature and newborn infants receiving parenteral nutrition, and the incidence of cholestasis was investigated after changing from polyvinylchloride infusion systems to polyvinylchloride-free infusion systems. MATERIALS AND METHODS: Two 3-year periods from 1998 to 2004 were investigated retrospectively before and after changing from polyvinylchloride to polyvinylchloride-free infusion systems in our department. This resulted in 1 group of 30 patients treated with polyvinylchloride lines and a second group of 46 patients treated with polyvinylchloride-free lines. The 2 groups were examined for the incidence of cholestasis and other possible contributing factors. Statistics were performed by using SAS software (SAS Institute, Cary, NC). RESULTS: After changing infusion systems, the incidence of cholestasis dropped from 50% to 13%. Using DEHP-plasticized polyvinylchloride infusion systems for TPN increased the risk for cholestasis by a factor of 5.6. The use of polyvinylchloride lines correlated strongly with the development of TPN-associated cholestasis (P = .0004). CONCLUSIONS: Using DEHP-containing polyvinylchloride infusions systems contributes to the development of cholestasis. Therefore, the use of DEHP-free infusion systems for TPN is recommended, especially in premature and newborn infants.

Long-term total parenteral nutrition-induced hepatobiliary dysfunction in a rabbit model

BACKGROUND/PURPOSE Currently, the reason for hepatobiliary dysfunction associated with long-term total parenteral nutrition (TPN) is much debated and still unclear. No agreement can be achieved about whether bacteriotoxins and sepsis, enteral starvation, consequences of abdominal operations, or the TPN solution itself is the real cause for the disease. Animal models were criticized for their short period of TPN and their failure to demonstrate cholestasis and bile duct proliferation. The aim of this study was to establish an animal model for long-term TPN in which the same alterations of the hepatobiliary system as observed in humans could be produced. METHODS In this model, rabbits could be kept for the first time under continuous TPN for 4 weeks. Three serial liver biopsy sections were taken operatively from each animal and biochemical analyses were performed four times. A control group of enterally fed rabbits underwent exactly the same procedure in respect to operations and handling, so that differences in macroscopical, biochemical, and histological changes between both groups could be attributed exclusively to TPN. RESULTS Only in the TPN group gallbladder distension developed in all animals after 1 week. After 3 and 4 weeks, viscous dark bile, sludge and stones, a slight rise in direct bilirubin, and a decline in plasma albumin and alkaline phosphatase was noted. In both groups liver biopsy results showed a similar degree of mild portal inflammation and single-cell necrosis at equivalent time points. These changes could be caused by antiseptics, antibiotics, anesthesia, and operations. Although mild to moderate proliferative changes and no hydropic degeneration developed in the control group during the same time, the TPN group generated marked proliferative and degenerative changes. We noted as early as 1 week after starting TPN a severe hydropic degeneration in 90% of the animals. Fibrosis and bile duct proliferation increased from a slight degree after 1 week up to a moderate to severe degree after 3 and 4 weeks, respectively. CONCLUSIONS The hepatobiliary alterations associated with TPN in children, which cannot be separated clinically from consequences of multiple other factors, can almost identically be reproduced in our rabbit model as a clear consequence of TPN. Furthermore, the hydropic degeneration of the liver cells begins in zone 3 and is an early predominant feature of hepatobiliary dysfunction in rabbits and infants. It must be rated as a response to a direct cytotoxic effect on the liver cell.

Extracorporeal membrane oxygenation in infants with congenital diaphragmatic hernia: follow-up MRI evaluating carotid artery reocclusion and neurologic outcome.

OBJECTIVE The purpose of our study was to prospectively assess, using MRI and MR angiography, the cerebral and vascular status of 2-year-old children with congenital diaphragmatic hernia (CDH) in whom carotid artery reconstruction was performed after neonatal extra-corporeal membrane oxygenation (ECMO) therapy and to compare the neurologic development of children with vascular reocclusion with that of CDH children with successful repair and with non-ECMO controls. SUBJECTS AND METHODS A total of 30 infants (17 boys, 13 girls; 2 +/- 0.26 years) were included. Of these, 18 (60%) infants received arteriovenous ECMO therapy with subsequent reconstruction of the right common carotid artery (RCCA). Two years postoperatively, the children were examined with cerebral MRI, including 3D time-of-flight and contrast-enhanced 3D MR angiography of the intra- and extracranial brain-supplying arteries. The pathologic findings were analyzed for the ability to predict impaired neurologic development. RESULTS The RCCA was occluded or highly stenotic in 13 (72%) of 18 children. All infants showed intra- and extracranial collaterals and a patent internal carotid artery. The average duration of ECMO was not longer than in cases of successful reconstruction (p = 1). The ECMO group showed a significantly greater incidence of cerebral injuries (p = 0.007) but no relevant impairment in neurologic development compared with controls (p = 0.26). Unsuccessful RCCA repair had no predictive value for a poor neurologic outcome (p = 1). CONCLUSION The outcome of RCCA repair after ECMO is possibly poorer than expected, with vascular occlusion or high-grade stenosis occurring in almost three quarters of patients. Although reocclusion of the RCCA does not increase the risk for cerebral lesions or an impaired neurologic development during the first 2 years postoperatively, the overall benefit of RCCA repair remains doubtful, and the potential long-term risk arising from these plaques has yet to be assessed.

Encouraging Early Clinical Experience with Deliberately Delayed Temporary Fetoscopic Tracheal Occlusion for the Prenatal Treatment of Life-Threatening Right and Left Congenital Diaphragmatic Hernias

Objective: In order to assess the effect of deliberately delayed percutaneous fetoscopic tracheal occlusion on survival of fetuses with life-threatening congenital diaphragmatic hernia. Methods: Eight fetuses with life-threatening congenital diaphragmatic hernia underwent fetoscopic tracheal balloon occlusion between 29 + 0 and 32 + 4 weeks of gestation. Delayed occlusion was chosen in order to minimize potentially negative pulmonary effects from premature delivery as a result of fetal surgery. In addition, we wanted to become able to provide all available postnatal intensive care treatment means in these patients. Results: Six of the 8 fetuses survived to discharge from hospital. Conclusion: Delayed fetoscopic tracheal balloon occlusion may be rewarded with lung growth sufficient to allow survival of fetuses with life-threatening congenital diaphragmatic hernia.