Stefan Gfroerer

Interstitial cells of Cajal in the normal human gut and in Hirschsprung disease

Hirschsprung disease (HD) is the most prevalent congenital gastrointestinal motility disorder. The pathogenesis of HD is defined as a functional intestinal obstruction resulting from a defect in the intrinsic innervation of the distal bowel. In addition to the enteric nervous system, the interstitial cells of Cajal (ICC) play an important role in the generation of coordinated gastrointestinal peristalsis. The major function of the ICCs is the generation of slow waves that allow these cells to act as specialised pacemaker cells within various tissues. ICCs have additional functions in the gastrointestinal tract as regulators of mechanical activity and neurotransmission. Due to the central role of ICCs in gastrointestinal peristalsis, it has been suggested that defects or impairments of the ICCs may contribute to motility dysfunction in several gastrointestinal motility disorders. This review describes the distribution and functions of ICCs in the normal gut and in Hirschsprung disease.

Tunneled central venous catheters in children with malignant and chronic diseases: A comparison of open vs. percutaneous implantation

PURPOSE Tunneled central venous catheters (tCVCs) are routinely used for long-term venous access in children with cancer and chronic diseases. They may be inserted by surgical venous cut-down or percutaneously. The aim of this study was to compare the operative times and intraoperative complications of both techniques. METHODS This study compared group A (surgical venous cut-down, years 2002-2006) with group B (percutaneous, years 2008-2012). Patient characteristics, operative times, and intraoperative complications were obtained from surgical reports. (IRB review and approval, number 6/15). Both Hickman/Broviac and Portacath catheters were included. RESULTS 343 patients in group A and 321 patients in group B were studied. Ages at implantation and underlying diagnoses were similar. Operative time was significantly shorter in group B. Only 60% of primarily dissected veins were suitable for surgical implantation, whereas successful vessel puncture was possible in 96% (87% on the first attempt, 9% on the second). Bleeding occurred in 2% of patients in group A, and pneumothorax occurred in 1.8% of patients in group B. Early catheter dislodgement was similar in both groups. CONCLUSION Percutaneous tCVC implantation is safe, less invasive, and faster than surgical implantation. Both techniques are feasible, and complication rates are low. LEVEL OF EVIDENCE Level III.

Malignant ectomesenchymoma in children and adolescents: Report from the Cooperative Weichteilsarkom Studiengruppe (CWS)

Malignant ectomesenchymoma (MEM) is a soft tissue tumor with heterologous rhabdomyoblastic components believed to arise from pluripotent migratory neural crest cells. To date merely 50 cases have been published and the knowledge about the course of disease and optimal treatment is limited.

Embryology of the testicular descent.

Numerous researchers studied the morphology of the testicular descent, including the possible function of the gubernaculum. However, a clear illustration of this process is still missing. The aim of this paper was to illustrate the embryology of the testicular descent in the rat by scanning electron microscopy. In a first phase of the intra-abdominal testicular descent, the testis moves actively from the lower pole of the kidney towards the bladder neck. In a second inguinal phase the testis enters groin and moves in the developing processus vaginalis peritonei caused by the disappearance of the bulb of the gubernaculums testis.

Pediatric intestinal motility disorders

Pediatric intestinal motility disorders affect many children and thus not only impose a significant impact on pediatric health care in general but also on the quality of life of the affected patient. Furthermore, some of these conditions might also have implications for adulthood. Pediatric intestinal motility disorders frequently present as chronic constipation in toddler age children. Most of these conditions are functional, meaning that constipation does not have an organic etiology, but in 5% of the cases, an underlying, clearly organic disorder can be identified. Patients with organic causes for intestinal motility disorders usually present in early infancy or even right after birth. The most striking clinical feature of children with severe intestinal motility disorders is the delayed passage of meconium in the newborn period. This sign is highly indicative of the presence of Hirschsprung disease (HD), which is the most frequent congenital disorder of intestinal motility. HD is a rare but important congenital disease and the most significant entity of pediatric intestinal motility disorders. The etiology and pathogenesis of HD have been extensively studied over the last several decades. A defect in neural crest derived cell migration has been proven as an underlying cause of HD, leading to an aganglionic distal end of the gut. Numerous basic science and clinical research related studies have been conducted to better diagnose and treat HD. Resection of the aganglionic bowel remains the gold standard for treatment of HD. Most recent studies show, at least experimentally, the possibility of a stem cell based therapy for HD. This editorial also includes rare causes of pediatric intestinal motility disorders such as hypoganglionosis, dysganglionosis, chronic intestinal pseudo-obstruction and ganglioneuromatosis in multiple endocrine metaplasia. Underlying organic pathologies are rare in pediatric intestinal motility disorders but must be recognized as early as possible.

Adenomyoma of the small intestine a rare pathological lead point for intussusception in an infant

IntroductionIntussusception is a typical abdominal emergency in early childhood.Case descriptionWe report a case of an infant in the typically affected age group with an intussusception triggered by a rare benign intramural intestinal adenomyoma as a pathological lead point. The infant had the typical symptoms of a recurrent idiopathic ileocolic intussusception.Discussion and evaluationIdiopathic intussusception is frequent in the infant age group. Contrary to that, reports on pathological lead points for intussusceptions are sparse in the toddler age.ConclusionsThat case illustrates that even in intussusceptions in the typically affected age group, it is important to be aware of pathological lead points, especially if the intussusceptions are recurrent.

Changes of smooth muscle contractile filaments in small bowel atresia.

AIM To investigate morphological changes of intestinal smooth muscle contractile fibres in small bowel atresia patients. METHODS Resected small bowel specimens from small bowel atresia patients (n = 12) were divided into three sections (proximal, atretic and distal). Standard histology hematoxylin-eosin staining and enzyme immunohistochemistry was performed to visualize smooth muscle contractile markers α-smooth muscle actin (SMA) and desmin using conventional paraffin sections of the proximal and distal bowel. Small bowel from age-matched patients (n = 2) undergoing Meckels diverticulum resection served as controls. RESULTS The smooth muscle coat in the proximal bowel of small bowel atresia patients was thickened compared with control tissue, but the distal bowel was unchanged. Expression of smooth muscle contractile fibres SMA and desmin within the proximal bowel was slightly reduced compared with the distal bowel and control tissue. There were no major differences in the architecture of the smooth muscle within the proximal bowel and the distal bowel. The proximal and distal bowel in small bowel atresia patients revealed only minimal differences regarding smooth muscle morphology and the presence of smooth muscle contractile filament markers. CONCLUSION Changes in smooth muscle contractile filaments do not appear to play a major role in postoperative motility disorders in small bowel atresia.

Systematic review shows that pathological lead points are important and frequent in intussusception and are not limited to infants

Intussusception is the most clinically relevant cause of bowel obstruction in infancy and can be idiopathic or occur as a result of pathological lead points. The incidence of these pathological lead points varies from 0.3 to 20%, and they can be mucosal, intramural or extrinsic structures. A systematic literature review was performed from 1998 to 2016 to evaluate the incidence and types of pathological lead points in paediatric intussusception, and this identified 31 epidemiological and retrospective case cohort studies, reviews and case reports.