Congenital diaphragmatic hernia: focus on abnormal muscle formation.

BACKGROUND: CDH is a major birth defect, characterized by high mortality. How the initial defective mesenchymal substructures affects muscle malformation is unclear. Defects of genes involved in diaphragmatic development, such as friend-of-GATA2 (Fog2), may play an important role in its pathogenesis. We investigated the expression of Fog2 and proteins of myogenesis in a series of CDH and in diaphragms at different fetal ages, in order to clarify the role of muscular components during diaphragmatic development in cases with CDH. MATERIAL AND METHODS: Specimen were obtained from seven diaphragms of CDH cases undergoing surgery, 3 entire diaphragms from non repaired CDH, 5 control diaphragms at different gestational ages (16, 17, 22, 32, and 40g.w.), and 3 biopsy samples of normal voluntary muscle. The thickness of diaphragms at the edge of the defect in CDH and in developing diaphragms was measured. All samples were processed for HE staining and immunohistochemistry. Immunohistochemical expression of MyoD, Myf4, Pax7, Mib1 and Fog2 was evaluated. RESULTS: Mean thickness at the edge of the defect was 4.14mm. Contralateral hemi-diaphragm in 3 autopsies and in controls at 32 and 40weeks measured 2.25mm; histology showed a higher density of desmin-positive muscular cells at the edge of defect. CDH displayed scattered Myf4-positive cells (range 0%-10%, mean 2.4%), numerous Pax7-positive cells (range 0%-24%, mean 12.1%) and less than 1% Mib1-positive cells. Controls showed a reduction of positive cell with the progression of gestational age for Myf4 (30% at 16 weeks, 20% at 17 weeks, 5% at 22 weeks, 1% at 32 and 40 weeks), Pax7 (85% at 16 weeks and 17 weeks, 35% at 22 weeks, 11% at 32 weeks) and Mib1 (20% at 16 weeks, 8% at 17 weeks, 7% at 22weeks, 2% at 32 weeks). Fog-2 was diffusely positive in mesenchymal, mesothelial and muscular cells, in diaphragms from 16 to 22 weeks, decreasing to 20% of positive muscular cells in 32-week diaphragm. In CDH only mesothelial and mesenchymal cells were positive. Stem cell markers were negative in cases and controls. COMMENT: CDH shows a thick muscular border, with high number of mature muscle cells and significant increase of quiescent satellite cells (PAX7+, Mib1-). Abnormal architecture may affect the normal process of myogenesis and thus signaling and cell-cell interactions of myocytes. The expression of Fog2 in mesothelial and mesenchymal cells in CDH demonstrates the absence of a genetic defect involving Fog2 in our cases. Being Fog2 expressed in muscle cells at early stage supports the hypothesis that the altered diaphragmatic genesis may undermine also the muscular component instead of the only mesenchymal one.

A cross-sectional nationwide survey on esophageal atresia and tracheoesophageal fistula.

BACKGROUND: Our study aims at disclosing epidemiology and most relevant clinical features of esophageal atresia (EA) pointing to a model of multicentre collaboration. METHODS: A detailed questionnaire was sent to all Italian Units of pediatric surgery in order to collect data of patients born with EA between January and December 2012. The results were crosschecked by matching date and place of birth of the patients with those of diagnosis-related group provided by the Italian Ministry of Health (MOH). RESULTS: A total of 146 questionnaires were returned plus a further 32 patients reported in the MOH database. Basing on a total of 178 patients with EA born in Italy in 2012, the incidence of EA was calculated in 3.33 per 10,000 live births. Antenatal diagnosis was suspected in 29.5% patients. 55.5% showed associated anomalies. The most common type of EA was Gross type C (89%). Postoperative complications occurred in 37% of type C EA and 100% of type A EA. A 9.5% mortality rate was reported. CONCLUSIONS: This is the first Italian cross-sectional nationwide survey on EA. We can now develop shared guidelines and provide more reliable prognostic expectations for our patients.

Early prenatal diagnosis of cloacal exstrophy with fetal magnetic resonance imaging.

Prenatal diagnosis of cloacal exstrophy can be challenging during pregnancy and, subsequently, the counseling very difficult. Available ultrasonographic criteria may be inadequate, especially in early gestational ages. A case of early prenatal detection of cloacal exstrophy with fetal magnetic resonance imaging is reported herein for the first time.

Polypoid lesion of the gallbladder in childhood: case report and literature review.

Gallbladder polypoid lesions are rare in the pediatric patient and sometimes represent an incidental finding. A 13 year old male was referred to the Padua Hospital Pediatric Department for an obesity. A routine abdominal ultrasound (US) detected a gallbladder polypoid lesion 6 mm in diameter, initially considered a gallbladder adenoma. Investigation did not detect any other biliary tract abnormality. After seven months, the asymptomatic patient underwent a follow-up US which revealed the disappearance of the polypoid mass. The following concerns are raised: what is the size of the polypoid mass that should be considered for surgery? How does the presence of symptoms worsen the diagnosis and lead to preferring a surgical approach (cholecystectomy) over an echographic follow-up?

[Serious dog bite lesions in childhood: presentation of 3 cases and literature review]. / Lesioni gravi da morso di cane in età pediatrica: descrizione di 3 casi e revisione della letteratura.

Animal bite lesions in the pediatric patient are mainly accounted for by dog bites in 80% to 90% of the cases. They often present a favorable prognosis but serious lesions do account for 5% to 20% of the total incidence. We will present three particular clinical cases which required urgent surgical treatment as well as a review of the current literature to include both medical and surgical treatment methods for this kind of lesion.

[Thoracoscopy: the pediatric experience in Padua]. / Toracoscopia: esperienza pediatrica a Padova.

INTRODUCTION: Thoracoscopy is an important option in the treatment of many thoracic pathologies; its use in children, however, is still limited. We have retrospectively evaluated the thoracoscopic activity in our pediatric surgery department in the last six years. METHODS AND PROCEDURES: Video-Assisted Thoracoscopy (VATS) has been routinely adopted in our institutions since 1997. The data of 115 patients who have undergone VATS were reviewed and analysed. RESULTS: There were 47 males and 68 females. Mean age at surgery was 66.08 (SD: 58.23) months. Mean body weight at surgery was 21.85 (SD: 16.26) Kg. The patients were divided in four groups according to the pathologies: Patent Ductus Arteriosus (PDA) (n = 95), Pleural Empyema (n = 14), Mediastinal Mass (n = 3) and Lung Disease (n = 3). Complicances were seen in two patients in the PDA group (one laryngeal nerve paralysis and one chylothorax) and one in the pleural empyema group (post-operative bleeding which required blood transfusion). CONCLUSIONS: VATS can be performed safely and with minimal morbidity. In our experience, early and late complications turned out to be quite low. This survey would support on-going development of thoracoscopy in children.

A new indication for buccal mucosal graft: isolated congenital fistula of the penile urethra.

Isolated congenital urethrocutaneous fistula is uncommon, and its repair has been associated with high incidence of recurrence. However, the use of buccal mucosal graft offers a satisfactory closure after previous failures. We report a new case in whom we adopted the buccal mucosal urethral replacement to treat the recurrence.

Use of urokinase in childhood pleural empyema.

Urokinase is an enzyme with a fibrinolytic effect that facilitates pleural empyema drainage through a chest tube. The aim of this study was to assess the risk of pneumothorax, the need for pleural debridement surgery, the persistence of fever, and the number of days in hospital in a group of children with parapneumonic pleural empyema treated with urokinase. This was an uncontrolled retrospective study on children suffering from parapneumonic empyema. Data collected on 17 children treated with urokinase were compared with 11 children treated prior to the advent of urokinase (the "historic" group). The urokinase was instilled in the pleural cavity over a period ranging from 2-8 days, amounting to a median total dose per kilogram of body weight of 18,556 IU (range, 7,105-40,299). Surgical treatment of the empyema involved drainage tube placement and/or debridement of the pleural cavity. Three children developed pneumothorax during their hospital stay, and one more case occurred 6 months after the child had recovered from his empyema; there were 3 cases of pneumothorax during the acute phase in the "historic" group (P = 0.54). Five children in the urokinase group were debrided and 12 were only drained, as opposed to 9 and 2, respectively, in the "historic" group (P = 0.02). The overall hospital stay was 17 days for the urokinase group, and 24 for the "historic" group (P = 0.02). No bleeding or other major complications were reported in the group treated with urokinase. In conclusion, urokinase treatment does not carry a risk of pneumothorax, while it does reduce hospital stay and the need for pleural debridement.

Carotid artery approach as an alternative to femoral access for balloon dilation of aortic valve stenosis in neonates and infants.

PURPOSE: to evaluate the efficacy of a right common carotid artery cutdown as alternative access in neonates and small infants requiring a balloon dilation of aortic valve stenosis. In infants, the femoral approach is limited by difficulties in advancing the catheter across the valve and by the risk of femoral artery injuries. METHODS: from January 1997 to July 2000, 16 infants at our department underwent balloon dilation through a carotid artery cutdown. Infant weight ranged from 2670 to 6450 g; mean weight 3967 g, and age ranged from 1 to 157 days, mean age 42,8 days. Fifteen of 16 infants had aortic valve stenosis; the remaining infant presented with a aortic coartation relapse. RESULTS: In 15 infants an adequate dilation of the valve was obtained with no complications. In only one infant an arterial intimal disconnection was caused by inadequate choice of surgical instruments. At the end of the procedure, the carotid arteries were reconstructed with interrupted 7-0 prolene stitches. There were no neurological sequaelae observed. All infants were followed-up and examined by echocolordoppler ultrasound: all carotid arteries were open with no significant stenosis. CONCLUSION: Our experience confirms that the carotid access proposed in 1973 by Azzolina et al is a valid and safe alternative to the usual percutaneous femoral access. In particular it could be useful in neonates and infants were the size of femoral vessels could facilitate important and dangerous complications.

[Values of white blood cell count in the diagnosis of acute appendicitis]. / Utilità della leucometria nella diagnosi di appendicite acuta.

BACKGROUND: The diagnosis of acute appendicitis remains a critical challenge for paediatric surgeons. White Blood Cell (WBC) count, once considered a basic exam, is still routinely performed in most institutions, despite its lack of accuracy. Aim of this study is to assess the additional value of WBC count in the diagnosis of acute appendicitis. METHODS: We retrospectively reviewed the charts of children who underwent appendectomy for acute appendicitis in the last two years at our institution. In the patients treated in 1999 (Group A), WBC count was assessed routinely after admission. The surgeons relied on leukocytosis as well as on clinical findings and on ultrasound abdominal scan for the diagnosis of acute appendicitis. In the patients treated in 2000 (Group B), blood cell count was not tested or deliberately ignored by the surgeons. RESULTS: There were 65 children in Group A and 70 in Group B; the two groups of patients were similar in terms of gender (p = 0.989) and age (p = 0.758). Criteria for operation were similar in the two groups (p = 0.222). No differences were found in the number of perforated (p = 0.989) and normal (p = 0.217) appendixes in the two groups as well as in the duration of hospital stay after surgery (p = 0.849). CONCLUSIONS: WBC count at admission has no proven additional value in the diagnosis of acute appendicitis and can be omitted without modifying diagnostic pathway and without affecting diagnostic accuracy.

Experimental abdominal wall defect repaired with acellular matrix.

In the surgical repair of congenital abdominal-wall defects (AWD), the ready availability of a non-immunogenic and non-prosthetic biomaterial that could guide the regeneration of normal tissue is a fascinating possibility. Biomaterials are already in use, but in our experience, an acellular matrix (ACM) can stimulate exact regeneration of the absent tissue. We explored the possibility of using an ACM to repair a muscular AWD in an animal model. Male New Zealand white rabbits (3-4 kg, n = 18) were anesthetized and the abdominal wall was shaved and scrubbed; a vertical incision was made in the left lower quadrant and a large patch of external-oblique muscle was resected (3 x 3 cm). The animals underwent reconstruction with homologous diaphragm acellular matrix (HDAM) grafts that were previously prepared using a detergent enzymatic method. The patches were evaluated histologically at 9 (n = 6), 40 (n = 6), and 90 (n = 6) days post-surgery in each group; moreover, 90 days post-surgery an electromyogram (EMG) (n = 6) of the implanted matrix was recorded. Histologic analysis demonstrated that the HDAM supported fibroblast migration, deposition of newly-formed collagen, and neovascularization. No signs of necrosis, or evidence of skeletal-muscle-cell ingrowth were detected. The EMG revealed minimum muscular electrophysiologic activity, probably due to muscle underlying the patch. The HDAM we employed was thus not able to produce reconstruction of the skeletal muscle, and was progressively remodeled into fibrous tissue. Since the ultimate reason for failure of muscle regeneration is a lack of myogenesis, future studies will use ACMs preconditioned by various regulators of myoblast proliferation and differentiation.

[Congenital and acquired chylothorax]. / Il Chilotorace congenito e acquisito.

BACKGROUND/PURPOSE: Chylothorax in paediatric age is a life-threatening clinical entity that cause serious respiratory, nutritional and immunologic complications. Chylothorax in the absence of trauma or tumour is uncommon and lymphangiomatosis of the bone, although extremely rare, has been associated with these condition. The authors describe the case of a two-year-old girl who presented with a massive chylothorax associated with hip and paravertebral lymphangioma and spread lymphangiomatosis of the spine. The authors also review the literature and their experience of congenital and postoperative chylothorax in order to establish guidelines for the diagnosis and management of both primary and postoperative chylothorax in paediatric age. METHODS: From 1990 and 1999, 14 children had chylothorax. 9 patients had pleural effusion after surgical procedure, 5 patients had congenital chylothorax (both in prenatal and neonatal time), one of whom with bone lymphangiomatosis associated. RESULTS: Postoperative chylothorax has been successfully treated by conservative approach (starvation, total parenteral nutrition and chest tube) in 6 out of 7 cases (two patients died because of complex cardiac malformation). Conservative approach is useful in case of congenital chylothorax, but not with bone lymphangiomatosis associated. CONCLUSIONS: Postoperative and congenital chylothorax is well managed with conservative treatment. Chylothorax with bone lymphangiomatosis associated needs early and aggressive surgical approach.

Treatment of Kasabach-Merritt syndrome by embolisation of a giant liver hemangioma.

We report the case of a 14-month-old child with Kasabach-Merritt Syndrome, due to a giant liver hemangioma. The therapeutic approach consisted of peripheral transcatheter embolisation of the right hepatic artery with Ivalon microspheres without the addition of thrombogenic material. This procedure brought to a sensible permanent reduction of the size of the liver hemangioma with normalisation of the previous altered coagulation parameters after 6 years of follow-up.

[The EX-utero Intrapartum Technique (EXIT) procedure in Italy]. / Il parto ex-utero intrapartum technique (EXIT) in Italia.

Aim of the study was to present the first two Italian cases of C-section performed with the EXIT procedure (EX-utero Intrapartum Technique). Deliveries were performed at the Division of Obstetrics and Gynecology of the Hospital of Padua in cooperation with the Pediatric Surgery Department, both tertiary care centers. The first case was a twin with a huge neck mass (cystic hygroma) and the second a fetus with an oropharyngeal mass (epignathus). Airway patency could have been compromised at birth in both of them. EXIT procedure consists in securing the airway of the fetus partially delivered and still connected with the placenta. This technique leaves an intact feto-placental circulation and guarantees a normal fetal oxygenation while fetal airway patency is secured. Both the fetuses were successfully intubated and the C-section ended up in a short period of time without maternal and fetal complications. The EXIT technique, performed for the first time in 1989 and now in many centers abroad, can be considered a safe procedure as long as a multidisciplinary approach is carried out. The EXIT procedure is indicated whenever fetal airways can be compromised at birth, that is when oropharyngeal masses, laryngeal atresia, cystic hygroma and goiter are encountered during prenatal ultrasound.

Congenital tracheobiliary fistula.

Congenital respiratory tract-biliary fistula, including tracheo- and broncho-biliary fistulae, are rare developmental anomalies. To date, only 18 cases have been reported. We present two additional cases that came to our attention after a long and difficult attempt to make a diagnosis. After surgical excision of the tract both children have remained symptom-free for 6 and 4 years, respectively. Bronchoscopy allows an early diagnosis, but patients also have to be investigated for associated biliary tree malformations.

Experimental defect in rabbit urethra repaired with acellular aortic matrix.

Urethral reconstruction following failed hypospadias repair or post-traumatic chronic stricture requires adequate amounts of tissue. Many surgical techniques utilizing different types of biological tissues have been attempted: (a) vascularized skin flaps from the prepuce, scrotum or penile shaft; (b) full-thickness free skin grafts; (c) vesical or buccal mucosa grafts; (d) ureter; artery; vein and appendix tissue. More recently, biodegradable polymers have also been used as delivery vehicles of urothelial cells in animals. It has been demonstrated that the implant of an acellular tissue matrix in the bladder can guide the regeneration of urothelium, blood vessels, smooth muscle and nerves. The aim of this study was to create an experimental model of urethral defect, and then repair it by implanting homologous acellular aortic grafts as urethral substitutes. An acellular matrix was obtained by detergent enzymatic treatment of rabbit thoracic aorta. The growth of urethral epithelium was verified in vitro, and homologous acellular vessels were then implanted in rabbits, bridging a previous surgical urethral defect. The outcome of reconstructive surgery was evaluated histologically at 10 days, 3 weeks, 3 and 12 months. As the time after surgery increased, the neourothelium became less thick, signs of inflammatory response disappeared, and the orientation of collagen fibrils and smooth muscle fascicles resembled that of a normal urethra. The implants displayed abundant vascularization, and the luminal surface started to become irregular. Acellular blood vessels may represent a promising approach to urethral defect therapy for different reasons: (a) unlimited availability, (b) readily obtainable in different lengths and gauges, (c) the potential for being organized as tissue bank, and (d) that just one simple surgical procedure is needed. Nevertheless, before this technique can be applied in humans, it must be tested in more species and animals.

Vascular access in patients affected by short bowel syndrome.

The aim of this study was to evaluate the problems induced by the use of a central venous catheter (CVC) in a series of patients with short bowel syndrome observed at the university of Padua (Italy) between January 1981 and June 1997. During this period, 14 patients required central venous access for parenteral nutrition (PN); 55 catheters were inserted, 6 with percutaneous and 49 with surgical techniques. We divided the patients into two groups according to PN duration. The first group includes 11 children with short/medium-term PN 8 are now eating, and 3 died from respiratory failure) while the second group includes 3 patients on home long-term PN. Thirteen catheters were placed in the first group, and the mean PN duration was 173 days; the three patients on home PN required 42 catheters. It is our experience that the use of catehters in patients requiring short/medium- term PN is a safe procedure with few complications; patients on home long-term PN present an increasing number of complications, and the vascular access could become a serious problem as the number of PN-dependent increases.

[Pyloric hypertrophic stenosis in the premature child. A clinical case]. / Stenosi ipertrofica del piloro nel bambino prematuro. Caso clinico.

Hypertrophic pyloric stenosis (HPS) is rare in premature infants. We report a case of HPS in an extremely low birth weight neonate (28 weeks of gestation, 622 gr), discovered on the 10th week of life. Although the diagnosis and treatment of pyloric stenosis has ben well established for many years, the presentation in preterm babies is atypical and the diagnosis often delayed. A brief review of literature is included.

Gene transfer in skeletal muscle by systemic injection of DODAC lipopolyplexes.

Lipid-based vectors are a promising tool for gene therapy applications. Several studies have reported their use in vivo to transfect different organs. Few data, however, are available about lipid-mediated gene transfer in skeletal muscle. Here we report the initial results obtained after systemic administration of lipopolyplexes based on the DODAC cationic lipid in an animal model of muscle regeneration. In particular, we compared three routes of administration: intravenous (i.v.), intracardiac (IC) and intra-arterial (IA). Analysis of reporter gene expression (luciferase) showed that regenerating muscle is more efficiently transfected in all cases and that IA injection is by far the best approach.