Search PubMed⌕ Search

Biomedical subjects

A Hebra

Publications and source records attributed to A Hebra.

At least 37 records · Page 2Linked to original sources

Enteric defensin expression in necrotizing enterocolitis.

Immaturity of local innate defenses has been suggested as a factor involved in the pathophysiology of necrotizing enterocolitis (NEC). The mRNA of enteric human defensins 5 (HD5) and 6 (HD6), antibiotic peptides expressed in Paneth cells of the small intestine, have significantly lower levels of expression in fetal life compared with the term newborn and adult. In the current study, intracellular HD5 was demonstrated by immunohistochemistry at 24 wk of gestation, but at low levels, consistent with findings at the mRNA level. These data suggest that the low level enteric defensin expression, characteristic of normal intestinal development, may contribute to the immaturity of local defense, which predisposes the premature infant to NEC. To test if levels of defensin expression are altered in NEC, specimens from six cases of patients with NEC and five control subjects (four patients with atresia and one with meconium ileus) were analyzed to determine HD5 and HD6 mRNA levels by in situ hybridization. Compared with the control group, the level of enteric defensin expression per Paneth cell assessed by image analysis was increased 3-fold in cases of NEC (p = 0.02, analysis of variance and covariance). In addition, the number of Paneth cells was increased 2-fold in the small intestinal crypts of NEC specimens compared with those of control subjects (p < 0.01, covariance analysis). In healthy tissue, peptide levels within Paneth cells paralleled mRNA levels through development. In tissue from infants with NEC, the steady state level of intracellular peptide was not increased in conjunction with the observed rise in defensin mRNA. A straightforward interpretation of this finding is that HD5 is actively secreted in this setting and the Paneth cells maintain a constant steady state level of intracellular peptide, but the possibility of translational regulation of peptide expression is also consistent with these data. The associations between NEC and enteric defensin expression reported here offer support for future studies to address the role of these endogenous host defense factors in the pathophysiology of this disease.

Adult↗

A new technique for laparoscopic splenectomy with massively enlarged spleens.

Splenectomy is indicated in several hematological disorders and it can be particularly challenging in children with sickle cell disease, splenomegaly, and recurrent sequestration. Over the last 6 months, we have developed a new technique for laparoscopic splenectomy (LS) for hypersplenism and splenomegaly in five children with sickle cell disease. The average age of our patients was 6 years (range, 2-11), and the average weight was 18.7 kg (range, 13.2-30.1). On preoperative ultrasound, spleen size index ranged from 0.42 to 0.76. For the LS, four trochars were placed. One patient, who also underwent a laparoscopic cholecystectomy, had six trochars placed, two of which were used for both cholecystectomy and splenectomy. After laparoscopic mobilization of the spleen and hilar vascular stapling, a Steiner electromechanical morcellator was inserted through the 12-mm port to extract cores of splenic tissue until complete splenectomy was achieved. No patient required conversion to an open procedure or creation of a larger incision to remove the massively enlarged spleen. Operative time averaged 190 minutes; the combined LS and cholecystectomy took 245 minutes. Postoperative length of stay was <2 days for all patients. There were no complications, and no patient required postoperative transfusion. Based on these early findings, we conclude that intracorporeal coring of splenic tissue allows for safe and complete laparoscopic removal of very large spleens in small children. It provides expedient recovery and minimal postoperative pain and scarring. This new technique should enable surgeons to perform LS even in patients with massive splenomegaly, eliminating the need for large and cumbersome intracorporeal bags or the creation of additional incisions to remove the spleen.

Child↗

Multidisciplinary approach to the treatment of pediatric pancreaticobiliary disorders.

A multidisciplinary approach using traditional open surgery, endoscopic retrograde cholangiopancreatography (ERCP) and laparoscopic surgery has revolutionized the care of the adult with pancreaticobiliary disease. This study focuses on a similar collaborative effort to diagnose and treat children with pancreaticobiliary disorders. Charts of all patients treated on the pediatric surgery service between June 1990 and May 1995, who also underwent ERCP, were abstracted for disease process, presenting symptoms, laboratory evaluation, surgical or endoscopic procedures, and eventual outcome. Twenty-six children were identified, ranging from 6 months to 19 years of age. Pancreaticobiliary disorders included pancreas divisum (n = 1), choledochal cyst (n = 4), pancreaticobiliary trauma (n = 4), cholelithiasis and choledocholithiasis (n = 17). The pancreaticobiliary tree was successfully visualized by ERCP in 25 of 26 (96%) patients. Fifteen of these patients also underwent attempted therapeutic endoscopic procedures, with 13 (87%) performed successfully. Three patients with choledochal cyst had stents placed preoperatively for cholangitis, all of whom have undergone successful choledochal cyst excision. Two trauma patients underwent attempted stenting of a bile leak and bile duct stricture, respectively, both of which were unsuccessful, necessitating surgical correction. Seventeen patients with cholelithiasis underwent ERCP to rule out choledocholithiasis. Ten patients were found to have common duct stones, and all stones were endoscopically extracted, including those in a 6-month-old child. Overall survival rate was 96% (25 of 26), with the one death occurring in a trauma patient unrelated to his pancreaticobiliary disorder. A multidisciplinary approach using traditional open surgery, ERCP and laparoscopic surgery can successfully treat even young children with pancreaticobiliary disorders. In experienced hands, diagnostic ERCP and therapeutic endoscopic intervention can be performed successfully in most pediatric patients, greatly simplifying the surgical management of these potentially complex problems.

Adolescent↗

Wandering spleen: a challenging diagnosis.

Wandering spleen is rare, particularly in children, and diagnosis is difficult. It usually occurs at 20 to 40 years of age, and most cases are seen in women. Diagnosis is difficult because of lack of symptoms, unless splenic torsion has occurred. Patients usually have an asymptomatic abdominal mass, an acute abdomen, or, most commonly, a mass associated with pain. Laboratory data are nonspecific, but the diagnosis can be confirmed by imaging studies; computed tomography and duplex ultrasonography are preferred modalities. Treatment is operative because of complications of splenic infarction and possible splenectomy. Splenopexy is the treatment of choice for a noninfarcted wandering spleen. Splenectomy should be done only when there is no evidence of splenic blood flow after detorsion of the spleen. We review our experience with wandering spleen in two pediatric patients, one treated with splenopexy and the other with splenectomy.

Abdominal Pain↗

Epstein-Barr virus-associated hepatic smooth muscle neoplasm in a cardiac transplant recipient.

Host immunosuppression is increasingly recognized as a significant risk factor for the development of a primary neoplasm. Chronic immunosuppressive therapy, as used in organ transplantation, may perturb the immunosurveillance ability of the host, making the patient more susceptible to virus-associated malignancies. We have taken care of a care of a child who received an orthotopic heart transplant and who then developed both a generalized lymphoproliferative disorder and a leiomyoma of the liver a year later. Epstein-Barr virus DNA was detected in a lymph node initially and the hepatic tumor cells subsequently. The former responded to a reduction in the immunosuppressive medications and the latter responded to surgical resection. This is the first report of a hepatic smooth cell neoplasm occurring following cardiac transplant and the development of two sequential Epstein-Barr virus-associated disorders in an immunosuppressed patient.

Child↗

Esophageal replacement using the colon: is it a good choice?

Thirty-eight children (2 months to 26 years of age) underwent esophageal replacement at our institution between 1962 and 1993. Twenty-four patients had esophageal atresia, with the replacement performed at a mean age of 17 months. The remaining patients (37%) had strictures and were older (mean, 7.4 years). Replacement procedures involved the right colon in 61% of cases and the transverse left colon in the others (39%). Sixty-three percent were placed substernally and 37% were done in transthoracic fashion. The average length of stay in the hospital was 34 days (range, 11 to 256 days.) Early complications (within 30 days) included cervical anastomotic leaks (11 patients; 29%) pneumonia (4), would infection (2), pneumothorax/hemothorax (3), wound dehiscence (1), prolonged ventilation (2), vocal cord paralysis (1), Horner's syndrome (1), pancreatitis (1), and perforated graft (1). Despite the incidence of early leaks, only two persisted long-term (more than 3 months). Other late complications included significant proximal strictures (5), and cologastric strictures developed in five patients. Seven cases were considered graft failures (18%), and all of these eventually require graft replacement. Additional problems included redundant graft requiring revision (4) and dumping syndrome (2). There were six cases of intestinal obstruction caused by adhesions. Four of these involved intrathoracic obstruction of the graft and two involved small bowel obstruction. There was only one death, which occurred late and was not related to the primary disease or procedure. Long-term follow-up data were available for 20 patients (53%). The follow-up period ranged from 1 to 33 years (mean, 12 years). Fourteen had excellent results after the initial interposition, being able to eat and function well without any further intervention. Seven patients (18%) have had poor results and 17 (45%) required additional procedures to obtain good functional results. In our experience, the colon continues to be a good option for esophageal replacement, but additional procedures frequently are necessary to optimize the functional outcome. Good results can be expected in the majority of cases, but late problems (ie, redundant colon and poor emptying) are not unusual, and careful follow-up is essential in the management of such patients.

Adolescent↗

Endodermal sinus tumor in children.

Malignant germ cell tumors account for about 3% of neoplasms in children, and endodermal sinus tumor (EST) is the most common histological subtype. The authors reviewed 22 years' experience (at their institution) in the management of 37 patients with this tumor. Fifteen of them (41%) had a sacrococcygeal primary, 10 had a testicular tumor (27%), 6 had an ovarian tumor (16%), 3 had a vaginal tumor (8%) and 3 had tumors at other sites (8%). Seven (19%) patients presented with metastatic disease, primarily pulmonary. The serum alpha-fetoprotein (AFP) level was elevated in all cases tested. The initial chemotherapy regimen included vincristine, actinomycin, cyclophosphamide (VAC), and Adriamycin (6 patients), but since 1985 the regimen has been changed to include cisplatin or Carboplatin, etoposide, and bleomycin (21 patients). Eight patients with testicular tumors initially were treated with surgical excision alone. Computed tomography results were a poor predictor of recurrence, but AFP surveillance was extremely sensitive. No second-look operation detected residual tumor in the absence of AFP elevation. Initial relapse for all patients tended to occur early (within 2 years), locally, and often with pulmonary metastases. Although historically the prognosis for patients with EST has been poor, the overall 2-year survival rate in this series was 70%. The best prognosis was among the children who had a testicular primary tumor (survival rate, 100%). The 2-year survival rate for patients with ovarian tumors was 67%; for those with sacrococcygeal primaries it was 60%. These results suggest that the prognosis for children with EST has improved significantly over the past decade. Contributing factors include therapy based on cisplatin, etoposide, and bleomycin, and relapse surveillance with serial AFP determinations. Second-look procedures should be reserved for patients who have an increasing level of serum AFP, suspicious computed tomography findings, and no obvious evidence of metastatic disease.

Adolescent↗

Management of the gastrointestinal tract and nutrition in patients with cloacal exstrophy.

Cloacal exstrophy is a rare condition in which there is a complex set of congenital anomalies that affect multiple-organ systems, including the gastrointestinal tract. Twenty-six patients with cloacal exstrophy have been treated at the authors' institution during the last 20 years. Gastrointestinal features usually included omphalocele, exstrophy of an everted cecal plate, a short blind-ending distal colon, imperforate anus, and, occasionally, a shortened small bowel. Additional gastrointestinal anomalies included four cases of colonic duplication, one duodenal web, and one malrotation. The average time until the initiation of enteral feeding after initial surgery was 15.6 days, and the time until discontinuation of total parenteral nutrition (TPN) was 36 days. One patient with short bowel syndrome died of TPN-associated liver failure. Five other patients exhibited short bowel physiology, but ultimately each was weaned from supplemental intravenous hyperalimentation. Four patients have undergone posterior sagittal anorectoplasty, and one has had perineal anoplasty. Of these patients, two are continent and one is free of soilage on a bowel management program. In the authors' experience with management of the gastrointestinal tract and nutrition in patients born with cloacal exstrophy, many patients initially exhibited short bowel physiology, although most eventually adapted. However, very few patients have been able to achieve bowel control.

Abnormalities, Multiple↗

Orthotopic liver transplantation for inflammatory myofibroblastic tumor of the liver hilum.

Inflammatory myofibroblastic tumor is a rare gastrointestinal neoplasm. The authors report the case of a 5-year-old girl who initially presented with gastric outlet obstruction secondary to an inflammatory myofibroblastic tumor along the lesser gastric curvature. A subtotal gastrectomy and wedge resection of a left hepatic lobe nodule were performed. Obstructive jaundice developed one month postoperatively. Computerized tomography, percutaneous transhepatic cholangiography, and selective celiac and mesenteric arteriography showed a mass that involved the left hepatic lobe, with concomitant high-grade biliary obstruction and portal venous encasement. Percutaneous biliary drainage was performed. During laparotomy, the tumor was found to be unresectable, and the patient was referred to the Liver Transplant Service at The Children's Hospital of Philadelphia. A total hepatectomy with temporary portocaval shunt was performed, leaving the inferior vena cava in situ. At the back table, an ex vivo left trisegmentectomy was performed, followed by reimplantation of the posterior segment of the right hepatic lobe. The reimplanted liver segment functioned poorly, and completion hepatectomy with portocaval shunt was performed 24 hours postoperatively, because of severe coagulopathy, intraabdominal bleeding, and hemodynamic instability. The patient's condition stabilized, and she was listed for urgent liver transplantation. The anhepatic state was managed with intermittent plasmapheresis. She had transplantation 72 hours later, and was discharged from the hospital 3 weeks postoperatively after an uneventful recovery. She remains disease-free and has normal liver function 8 months after transplantation.

Child, Preschool↗

Thoracoscopic management of empyema in children.

The appropriate management of empyema in children is controversial. Traditional surgical approaches have included thoracotomy and open drainage, decortication, and thoracoplasty. While generally effective, these procedures can be associated with considerable morbidity. We have sought to assess the utility of video-assisted thoracoscopic adhesiolysis and pleural debridement for the treatment of empyema in children. Nine children with postpneumonic empyema unsuccessfully managed with a single attempt at closed tube thoracostomy underwent thoracoscopic drainage during the past 2 years. The empyema was successfully treated with this technique in seven patients with no further interventions being required. Procedures performed early in the fibrinopurulent stage were technically easier. The average time before chest tube removal was 8.5 days. An immunocompromised patient required a subsequent open decortication and a patient with a coagulopathy required two subsequent open procedures for drainage of a recurrent hemothorax. We conclude from this experience that video-assisted thoracoscopic adhesiolysis and pleural debridement can be successfully performed in children. Benefits include good visualization of the entire thoracic cavity for more effective debridement and efficient drainage, and subjectively diminished postoperative pain and associated morbidity.

Adolescent↗

Intestinal perforation due to an ingested foreign body: laparoscopic management.

The authors report the case of a previously healthy 10-year-old boy who accidentally ingested a toothpick. He presented to the hospital 7 days after the incident with left lower quadrant abdominal pain and fever; there was evidence of localized peritoneal irritation by exam. He had mild leukocytosis. An abdominal CT scan showed the toothpick in the sigmoid colon with extension through the bowel wall. Laparoscopic exploration was undertaken and an 8-cm toothpick was identified and removed from the perforation site in the sigmoid colon. Via a small suprapubic incision the sigmoid was delivered and repaired. The patient had an uneventful recovery and was discharged home 2 days after the procedure.Laparoscopic exploration can be diagnostic and therapeutic in the management of ingested foreign bodies with suspected intestinal perforation.

Child↗

Laparoscopic oophorectomy in children.

Laparoscopy is a well-established diagnostic and therapeutic modality for adult gynecologic surgery. We have sought to assess the feasibility of the laparoscopic approach to a particular gynecologic procedure, oophorectomy, in the pediatric population. Five patients under-went laparoscopic oophorectomy during the past year. The indication for oophorectomy in three cases was ovarian torsion---one in association with a hemorrhagic cyst another with a benign teratoma, and one that occurred prenatally. The fourth patient had a teratoma with significant solid component and the final patient was a young with Turner's syndrome who had laparoscopic exploration and removal of bilateral streak ovaries. Oophorectomy was successfully completed laparoscopically in each patient. In two cases a trocar site had to be widened to remove the specimen from the abdominal cavity. Post operative recovery was prompt, with time to discharge being an average of 2 days. From this experience we conclude that laparoscopic oophorectomy can be successfully accomplished in infants and children. It is technically an easy procedure and has the benefits of excellent visualization of the entire lower abdomen and pelvis including the contralateral ovary, rapid postoperative recovery, and good cosmetic result.

Adolescent↗

Octreotide does not prevent bacterial translocation in an infant piglet model of intestinal ischemia-reperfusion.

The process of bacterial translocation (BT) after ischemia/reperfusion (I/R) injury is reported to be mediated by local mucosal factors, the effects of pancreatic enzymes, epithelial disruption, and by dysfunctional intestinal motility. Octreotide (OCT), a somatostatin analog, has been postulated to protect against BT by influencing one or more of these factors. Twenty-two formula-fed piglets (weight, 3.5 +/- 0.5 kg; age, 20 +/- 5 days) were divided into four groups: control (no drug given; no I/R; n = 6), I/R (no drug given; n = 5), I/R plus low-dose OCT (LD OCT, 0.08 microgram/kg; n = 6), and I/R plus high-dose OCT (HD OCT, 8 micrograms/kg; n = 5). All experimental subjects had nonocclusive mesenteric ischemia induced by reversible pericardial tamponade with mesenteric flow decreased to 25 +/- 5% of baseline for 5 hours followed by 15 +/- 5 hours of reperfusion. Mesenteric lymph nodes (MLN), liver, spleen, blood, and peritoneum were harvested for blind microbial analysis. None of the animals in the control group experienced translocation to the tissues tested. All of the animals in the I/R group experienced BT to the MLN. The subjects in the LD OCT and HD OCT groups experienced BT to the MLN 66% and 80% of the time, respectively. Despite the reported clinical evidence that OCT can protect the intestinal mucosa from injury and increase the clearance of bacteria from the gastrointestinal tract, in this study in which variables other than I/R known to promote bacterial translocation were eliminated, OCT failed to modify or prevent the occurrence of translocation to the MLN after I/R injury.

Animals↗

Bacterial translocation in mesenteric ischemia-reperfusion injury: is dysfunctional motility the link?

The authors previously reported that mesenteric ischemia and reperfusion (I/R) in a chronic newborn piglet model creates dysfunctional intestinal motility. Whether this leads to inadequate bacterial clearance and translocation (BT) through the gastrointestinal tract remains unclear. To test this hypothesis the authors used their chronic piglet model (weight, 3.5 +/- 0.3 kg; age, 18 +/- 4 days; on formula feeding); nonocclusive mesenteric ischemia was induced via reversible pericardial tamponade. Mesenteric flow (SMA Doppler measurement via the retroperitoneal approach) was decreased to 25% +/- 5% of baseline for 300 minutes in the ischemia group (n = 7) and followed by 14 hours of reperfusion in the I/R group (n = 6). Control subjects had a sham operation (n = 7). Mesenteric lymph nodes (MLN), liver (L), spleen (S), ileum, peritoneum, and blood were harvested for blind quantitative microbial analysis. Subjects in the control group had no cultures positive for growth. Eighty-five percent of animals in the ischemia group had positive MLN cultures only (P < .05 v control). All piglets in the I/R group had positive MLN cultures (P < .05 v control), and one third of them manifested bacteremia. Histological examination did not show mucosal disruption in any group. The validity of this model is confirmed by the negative cultures in the control group and by the presence of normal ileal flora in all animals. In the ischemia and I/R groups, MLN cultures were consistently positive with gram-negative bacilli (Escherichia coli and/or Klebsiella pneumoniae). When subjects of the I/R group had more than 1,000 colonies in the MLN, bacteremia with the translocating organisms was also identified.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

The effects of ischemia and reperfusion on intestinal motility.

The interdigestive migrating motor complex (MMC) has been demonstrated to be a reliable indicator of intestinal motility and function. The effects of low perfusion on the MMC have never been studied. Fourteen newborn Yorkshire piglets (5 to 18 days old, weighing 2.9 +/- 0.4 kg) underwent celiotomy under general anesthesia with placement of four jejunal electrodes (50 cm apart) as well as a superior mesenteric artery (SMA) Doppler flow probe and a pericardial catheter. Group 1 (n = 5) had operation alone. Group 2 (n = 9) had nonocclusive mesenteric ischemia induced by reversible cardiac tamponade for 5 hours between postoperative days 6 to 12. All subjects had MMC phase III electrical activity, cycling time, and propagation velocity recorded daily. In group 2 MMCs were recorded prior to and during ischemia, and during reperfusion. Group 2 animals had 75% +/- 4% decrease in SMA flow during the tamponade period. During the ischemic period, the MMC cycling time (CT) increased from 67 +/- 10 (mean +/- SEM) to 98 +/- 12 minutes (P < .05) and MMC propagation velocity (PV) decreased to 4.2 +/- 2.2 from a baseline value of 10.5 +/- 1.5 cm/min (P < .05). During reperfusion CT and PV values were not significantly different from baseline. The validity of this model is confirmed by the comparable baseline recordings in groups 1 and 2, and by the return of MMC to baseline values within 4 to 7 hours of reperfusion, as seen in group 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗