Results of the operative treatment of gastroesophageal reflux in childhood with particular focus on patients with esophageal atresia.

AIM: Although the literature on fundoplications in childhood is relatively extensive, only few reports exist which correlate the rate of complications with the primary disease. Other important questions such as the incidence of postoperative dumping syndrome or Barrett's esophagus in childhood are barely treated. Nor have operative techniques such as single or double-row cuff sutures or the benefit of performing pylorotomy or pyloroplasty in addition to fundoplication been investigated with respect to their recurrence rates. In particular studies on laparoscopic fundoplications tend to be generally confined to a discussion of the feasibility of the endoscopic procedure, the duration of the intervention, the length of the hospital stay and the costs. The study presented here aims to analyze such still unanswered questions listed above for open fundoplication procedures, including an analysis of the authors' own patient population, and to discuss the questions together with the most important reports in the literature. The aim is to create a basis for later studies which will compare conventional and laparoscopic fundoplications. METHODS: In the period between 1993 and 2005, 160 children underwent a fundoplication procedure. From 2003 onwards, fundoplications were carried out laparoscopically. The data of 148 patients were analyzed, some of them on the basis of clinical follow-up and some on the basis of an extensive questionnaire and among others with the help of the parents' support group KEKS. RESULTS: The underlying disease in 87 patients was reflux disease stemming from esophageal atresia, previous diaphragmatic operation in 8 children and mental retardation with swallowing difficulties in 30 patients. Only 23 patients suffered from isolated gastroesophageal reflux disease without an underlying primary disease. Intraoperative complications occurred in 4.6 % of patients with esophageal atresia (EA), while the rate for the remaining collective of patients was 1.6 %. Postoperative complications were observed in 10.3 % of the children with esophageal atresia and in 8.2 % of the other cases. The recurrence rate was 16.1 % in the children with EA and 6.5 % in the other cases. Dysphagia and/or stenosis occurred in 17.2 % and 6.5 % of children, respectively, and dumping syndrome was observed in 18.3 % of the EA group and only in 1.6 % of the comparison group. An evaluation of 79 esophageal biopsies showed no difference between patients with EA and the comparison group concerning the degree of histological changes. When evaluating the suturing technique, it was found that a double-row fundus suture was more effective in preventing reflux recurrence than a single-row suture but also resulted in an increased rate of dysphagia. When considering the not infrequent occurrence of dumping syndrome, it was found that drainage operations such as pyloroplasty or pyloromyotomy are only indicated for reduced gastric motility. The data of the children without EA, who initially served as a comparison group, was analyzed further. Four summaries of the current literature in table form complete this discussion. CONCLUSION: Particularly in children with EA, Nissen fundoplication cannot be considered a procedure with few complications. The problems resulting from disturbed gastric and esophageal motility should not be underestimated nor should the postoperative occurrence of dumping syndrome. Postoperative long-term follow-up until the patients reach adulthood is absolutely necessary to ensure that development of a Barrett's esophagus is not overlooked.

Updated results on intestinal neuronal dysplasia (IND B).

BACKGROUND: Intestinal neuronal dysplasia (IND B) is still a subject of controversy. The aim of this paper is to review the present state of knowledge on IND B. A summary is given of the technical and diagnostic criteria which have to be considered in order to arrive at a reliable diagnosis. In addition, the available therapeutic interventions are discussed. METHODS: Between 1992 and 2001, 3984 colonic mucosal biopsies from 1328 children were investigated. Nerve cell staining was performed on native tissue sections: 15 microm thick cryostat sections, which, after spreading and drying on a microscopic slide, have a final thickness of 4-5 microm, with dehydrogenase reactions (lactic dehydrogenase, nitroxide synthase, succinic dehydrogenase). The biopsies were taken 8-10 cm above the dentate line (proximal to the ampulla recti, because of the caudo-cranial increase of giant ganglia proximal to the 4 cm biopsy) with a sufficient amount of submucosa. The criteria for IND is 15-20 % submucosal giant ganglia with more than eight nerve cells in 30 sections of a single biopsy (i.e. four to seven giant ganglia). RESULTS: The diagnosis of IND B is quantitative. A diagnosis of IND B was made over the past 10 years in 51 Hirschsprung resections (about 5 per year; 6 % of all Hirschsprung cases), and in 92 children with chronic constipation (about 9 children per year; 2.3 % incidence). Up to their fourth year of life, most children with isolated IND can be treated conservatively. This is due to the delayed maturation of the enteric nervous system which is characteristic of IND B. Only children who showed an additional hypoplastic hypoganglionosis were treated surgically. Children with Hirschsprung's disease (HD) and IND B proximal to the aganglionosis often showed, in those cases with a disseminated IND, postoperative disturbances in intestinal motility. CONCLUSION: The diagnosis of IND B requires that biopsies are taken proximal to the ampulla recti (about 8-10 cm above the dentate line) with a sufficient amount of submucosa. The biopsies must be cut rectangular to the surface of the mucosa. A diagnosis of IND B can be made only if, in the submucosa of 30 serial sections, 15-20 % of all ganglia are giant ganglia with more than eight nerve cells. Ganglioneuromatosis (MEN2B) must be clearly differentiated from IND. The clinical course of IND B depends on the extent of disturbed bowel innervation, the severity of motility failure, and the coexistence of MH. The conservative management of isolated IND is possible in most children. In individual cases, however, a transient enterostomy or a segmental resection is unavoidable.

Diagnosis and therapy of ultrashort Hirschsprung's disease.

BACKGROUND: Although ultrashort Hirschsprung's disease (UHD) was enzyme-histochemically characterised about 35 years ago, its existence is still often ignored. The aim of this study is to summarise the clinical diagnostic, incidence, gender ratio, morphological characteristics, and therapy over 15 years. METHODOLOGY: The reliable diagnosis of suspected UHD requires a minimal enema of contrast medium to exclude Hirschsprung's disease (HD). In UHD during pressing or crying no reflux of contrast medium is observed. Final proof of UHD is an enzyme-histochemical biopsy examination of distal rectal mucosa. The biopsies must demonstrate submucosa and be taken from the dentate line and 1 cm, 2 cm, 4 cm and 6 cm above the dentate line. The cryostat sections must be cut 15 microm thick; this thickness is reduced to 4.5 microm by the thawing, spreading and drying of the sections on microscope slides. A reliable diagnosis of UHD needs an enzyme-histochemical acetylcholinesterase reaction of native sections of rectal mucosa. RESULTS: UHD develops with first symptoms of chronic constipation in the second half of the first year of life. The chronic constipation proves to be therapy resistant. In HD constipation occurs in the first weeks of life or after weaning. In contrast to HD, no nerve fibres with increased AChE activity are observed in the lamina propria mucosa. Nets of nerve fibres with increased AChE activity can be found only in the muscularis mucosa and the musculus corrugator cutis ani (MCCA). The therapy of choice has proven to be a partial myectomy of the distal internal sphincter if dilatation of the internal sphincter was ineffective. UHD is either limited to the anal ring, or extends 3 - 4 cm into the distal rectum. Over the past 15 years, UHD had in our series an incidence of 13.4 % of all aganglionoses. The gender ratio of girls to boys was 1 : 2. CONCLUSION: UHD is reliably diagnosed by an AChE reaction in native biopsy sections from the anocutaneous transitional zone and, potentially, from 3 - 4 cm above the pectinate line. As UHD is always accompanied by aganglionosis of the distal internal sphincter, an increase in AChE activity is observed in the nerve fibres of the MCCA. The therapy of choice is a partial myectomy of the distal internal sphincter.

Long-term results of Rehbein's procedure: a retrospective study in German-speaking countries.

AIM: In contrast to other countries, no collective study of Rehbein's procedure in German-speaking nations has been performed. Therefore, our intention was, analogously to Goto and Ikeda's (10) Japanese study in 1984, Kleinhaus's (13) study on Swenson's procedure in 1979, Bourdelat's (2) French-Canadian investigation into Duhamel's technique in 1997 and Martuciello's (11) and Teitelbaum's (16) follow-up in the year 2000, to perform a follow-up study of Rehbein's technique of deep anterior resection. METHODS: The data of 200 patients from 22 German-speaking centers in Switzerland, Austria and Germany were collected. These data were gathered by questionnaire and the children were followed up in the individual participating hospitals for at least 3.5 years after the procedure. The procedure was performed between 1993 and 1997, over a 5-year period. The questionnaire contained 74 items including anamnestic data, diagnostic postoperative treatment and reoperations. RESULTS: Concerning the incidence of anastomotic leaks and resolving anastomotic strictures there was no significant difference between the results in our series and those of the collective analyses made by Hofmann von Kap-herr (7), Holschneider (9) and Sherman (18). In 6.6 % of the 191 patients an anastomotic leak and in 9.9 % a rectal stricture, which had to be dilated, was observed. Concerning late complications, 22.8 % of the children suffered from constipation, 4.3 % from encopresis, 10.6 % from enterocolitis and only 0.5 % from enuresis. The frequency of constipation diminishes over the years. A comparison of the different large series in the literature clearly shows that the incidence of constipation is higher after Rehbein's procedure and the frequency of urinary incontinence and encopresis higher following Swenson's, Soave's and Duhamel's techniques. The incidence of enterocolitis is less after Rehbein's procedure than after Swenson's, Soave's and Duhamel's techniques. CONCLUSIONS: The different results in the literature are due to the individual experience of the author, the very different follow-up methods and the date of follow-up. Therefore, the different results are hard to compare with our study. Nevertheless, Rehbein's anterior resection still could be presented as an adequate and important method to treat Hirschsprung's disease.

Results of total and subtotal colon resections in children.

AIM: The treatment of long-segment neuronal intestinal malformations confronts the paediatric surgeon with the problems of diagnosis, suitable surgical methods and postoperative care. The evidence based only on ganglion cells is inadequate to decide about the required extent of resection and does not exclude hypoganglionosis and disseminated dysganglionosis. For the surgical treatment, pouch procedures as well as the usual resection techniques according to Rehbein, Soave, and Duhamel are discussed. Since studies with greater numbers of patients are rare, we present here our own results. METHODS: 48 patients with long segment intestinal malformations were treated in our hospital between 1990 and 2000. A total of 35 patients were examined 1.5-6 years after definitive surgical therapy. Rehbein's anterior resection was performed in all cases. RESULTS: Our findings showed that the surgical treatment with Rehbein's technique offers good results, both with respect to complications as well as to the postoperative course, although a 4 cm long aganglionic segment remains in situ. We found that results were better after ascendorectostomy (n = 22) compared to ileorectostomy (n = 11). Earlier publications of this group (13) show that the histology of the proximal resection margin is decisive for the prognosis. Hypo- and aganglionic segments should be completely resected while short IND segments of the colon or terminal ileum may remain in situ. However, the additional effect of the aganglionic segment of the distal rectum and the decreased peristaltic flow of the pre-anastomotic bowel has to be taken into account. Further investigations are required to find out whether a combination of Soave's endorectal pull-through with a remaining neuronal dysplastic segment proximal to the resection margin may give better results or if the frequency of postoperative enterocolitis and incontinence increased in cases of long segment intestinal neuronal malformations. Accurate diagnosis of myenteric plexus is decisive for an optimal treatment and therefore, considering our results, it is essential that in case of newborns getting to hospital with colon obstruction and suspicion of neuronal intestinal malformation full thickness biopsies from the distal and proximal colon may be taken simultaneously with the enterostomy. Generally ileostomy is performed in patients suspected of long-segment neuronal intestinal malformations. Mucosa suction biopsies from the distal and proximal stoma side are less informative compared to full thickness biopsies.

Mitochondrial myopathy (complex I deficiency) associated with chronic intestinal pseudo-obstruction.

We report a patient presenting with severe muscular impairment and chronic intestinal pseudo-obstruction (CIP) at the age of eight months. Due to the aggravated symptoms, assisted ventilation, an ileostomy and total parenteral nutrition were required. Later on, the patient developed a locked-in syndrome (Leigh's subacute necrotising encephalomyelopathy) and finally died due to recurrent pneumonia and chronic renal failure. The assessment of muscle biopsies revealed a moderate single-fibre type II atrophy, a variation of muscle fibre calibre with focal fatty degeneration and a decreased reactivity of cytochrome-c oxidase. Although ragged red fibres had not been found, mitochondrial enzyme activities were markedly decreased with the lowest residual activity detected for NADH:Q1 oxidoreductase and NADH:O2 oxidoreductase (complex I deficiency), thereby confirming the diagnosis of mitochondrial myopathy. A molecular genetic analysis could not identify known mutations of mitochondrial DNA. Gastrointestinal full-thickness biopsies revealed myenteric hypoganglionosis of the colon and stomach and hyperplasia of the submucosal plexus of the ileum. Some of the intestinal smooth muscle cells displayed bulbous protrusions filled with lateralised mitochondria. Mitochondrial myopathies are known to be associated with a variety of clinical syndromes including CIP. However, in contrast to previous reports in which CIP has been attributed to visceral intestinal myopathies, the present case is characterised by neuronal intestinal malformations. Therefore, a mitochondrial myopathy associated with CIP requires a subtle assessment of both the intestinal smooth muscle and the enteric nervous system to identify the underlying pathology.

Training in pediatric surgery--a comparison of 24 countries in Europe and other countries around the world.

What is the training in pediatric surgery like, how is pediatric surgery defined in other countries and what are the possibilities of quality control for training in pediatric surgery? The results of an inquiry together with information about training in pediatric surgery in 24 countries are summarised to show the different possibilities of organising training in pediatric surgery inside and outside Europe. The number of trainees in pediatric surgery (ranging from 0 to 339 trainees per country), the density of pediatric surgeons (ranging from 424 to 35 714 live births/year per pediatric surgeon) and the number of Centres of Pediatric Surgery (ranging from 4167 to 65,000 live births or 450,000 to 5,300,000 inhabitants per Centre) varies a lot in the different countries. Countries with a higher density of pediatric surgeons often also have a higher number of trainees irrespective of the birth rate and the number of inhabitants within the country, indicating a good infrastructure for pediatric surgery. In 87.5 % of the countries pediatric surgery is recognised as a specialty. The mean duration of training is about 6 years and 3 months, excluding the countries where it is necessary to become a fully accredited general surgeon before doing pediatric surgery. The mean duration of stay in general surgery is 2 years and 10 months. In one third of the countries it is obligatory to spend some time (3 to 12 months) in pediatrics. An elective or a compulsory period of time (1 - 6 months) in other specialties such as orthopedic surgery, plastic and reconstructive surgery, thoracic surgery and urology exists in 41.7 % of the nations. The most common subspecialties within pediatric surgery practised during the training by the resident are abdominal surgery, thoracic surgery, oncological surgery, head and neck surgery and urology. Possible means of control to guarantee a high quality of training include a defined time of stay in each subspecialty, the number of operations done by the trainee or the number of cases treated by the resident in the respective subspecialty and the distinction of different levels of surgery done by the trainee during his residence. In many cases the type of control is not specified.

Surgical methods for anorectal malformations from Rehbein to Peña--critical assessment of score systems and proposal for a new classification.

In this review article the surgical techniques of Rehbein, Romualdi, Kiesewetter, and Peña/De Vries are compared and corresponding surgical steps are pointed out. Peña/De Vries have adopted many surgical steps from Stephens and further standardized this technique. The results of recent postoperative examinations are presented with regard to the surgical methods of Stephens, Rehbein, Romualdi, Kiesewetter, and Peña. In that connection, the paper makes it clear that comparison of postoperative studies is not possible because the authors evaluate too small numbers of cases, use different scoring systems, do not indicate individual steps of their surgical techniques and do not consider the height of the atresias. The reference to the type of fistula that can be found in recent literature unfortunately does not provide a common basis for comparative studies either. Therefore, the paper suggests complete abandonment of scoring systems and classification of postoperative continence results instead according to the therapy that has to be applied. In addition, it again stresses the importance and necessity of adhering to the Wingspread classification.

Reduction of latex sensitisation in spina bifida patients by a primary prophylaxis programme (five years experience).

Spina bifida patients represent a group with the highest risk for latex sensitisation and allergy with life-threatening symptoms mostly during surgery. At the end of 1995 we initiated a primary latex prophylaxis around and during surgery and anaesthesia of all spina bifida patients. The aim of our study was to investigate the prevalence of latex sensitisation in the spina bifida patients born during the five years after establishing latex prophylaxis in the Cologne Children's Hospital in December 1995. We investigated 34 serum samples of 27 spina bifida patients (mean age 2.4 years) for specific IgE antibodies against latex allergens (CAP system) and compared these patients born after 1995 with 38 spina bifida patients up to 5 years of age (mean 3.1 years) born before. In the prophylaxis group two of 27 patients (7 %), one of them with two operations outside the Children's Hospital, had low specific IgE against latex ( 100 kU/l (mean 22.6 kU/l, min 0.4 kU/l). Sera of 22 patients remained negative for latex IgE (min. 1, max. 19, mean 4.3 operations). By primary latex prophylaxis during surgery, anaesthesia and in paediatric wards the prevalence of latex sensitisation can be significantly reduced even in the high risk group of spina bifida patients. Problems can arise by the need for surgery in hospitals not experienced in the treatment of spina bifida patients, where latex prophylaxis is neglected.

Pathophysiology of chronic constipation in anorectal malformations. Long-term results and preliminary anatomical investigations.

Posterior sagittal anorectoplasty provides an optimal access to reconstruct the muscle complex in anorectal malformations. It gives much better results than the abdominoperineal pullthrough procedures performed before 1984. However, severe chronic constipation occurs postoperatively in about 10 % of the patients, which can only be treated by washouts. Clinical investigations of 578 patients treated from 1962 to 1984 and from 1985 to 1997 are presented here and both groups are compared to each other. In addition, a new continence score with special regard to chronic constipation and overflow incontinence was used to follow up 133 patients of the second group. The score distinguishes between children above and below the age of 3 years. To study the underlying reasons of severe chronic constipation in children with anorectal malformations, macro- and microanatomical investigations on 4 normal newborns, 3 neonatal piglets with imperforate anus and 25 rectal biopsies from the caecum were performed. The following reasons have been found to be probably responsible for postoperative constipation and overflow incontinence: 1. Malformations of the smooth and striated muscle fibres or connective tissue of the caecum; 2. Malformations of the intramural nerve plexus such as aganglionosis, hypoganglionosis or IND; 3. Malformations and/or iatrogenic lesions of the extramural nerve supply which runs anterior to the rectum and in front of the fascia of Denonvilliers, which can hardly be identified in neonates with imperforate anus. Therefore iatrogenic bladder injuries may occur after PSARP after extended mobilisation of the caecum. The macro- and microanatomical situation in the piglet with imperforate anus is totally different from the human newborn.

Paediatric surgical reality in Germany and visions for the future.

Over the past 2 centuries paediatric surgery has developed into a well-recognised, independent surgical speciality comparable to plastic surgery or thoracic and vascular surgery. About 550 members of the GAPS (German Association of Paediatric Surgery) annually treat about 2-3% of all 0-15-year-old children of the FRG and operate 32.5% of all children who need a surgical intervention in paediatric surgical centres. There are 83 paediatric surgical centres in the FRG. Most of them perform more than 2000 operations per year. Three newer developments are likely to influence the future of paediatric surgery in Germany: 1. demographic factors, particularly the massive reduction of the reproduction rate from factor 1 to 0.59; 2. the new German National Health Care System, called "Strukturreform 2000", which will introduce the Australian DRG system and a new administrative structure permitting only a restricted care of the patients under tight economic control; and 3. the European regulations of the UEMS/EBPS which the national Landesärztekammern will be required to adopt.

New pathogenetic aspects of gut dysmotility in aplastic and hypoplastic desmosis of early childhood.

The peristaltic movement of the gut is a function of the alternating contraction and relaxation of circular and longitudinal muscles. This movement is induced by a tendon-like connective-tissue net (TCTN) in the circular and longitudinal muscles, which are both rooted in a connective-tissue plexus layer (CTPL). In children with a therapy-resistant aperistaltic or hypoperistaltic syndrome who had normally-developed enteric innervation, a lack of the TCTN in the muscularis propria was observed. Over the last 2 years, 241 children with chronic constipation were investigated histopathologically; 46 children surgically treated by partial resection of the gut or diagnostically investigated by whole-mount biopsy. Fifteen children had a hypoperistalsis syndrome and 3 had an aperistalsis syndrome. All specimens were native and cut in a cryostat. Enteric innervation was examined by acetylcholinesterase and dehydrogenase reactions. The TCTN in the muscularis propria was stained with picric acid/sirius red. In the children with an aperistalsis syndrome, a complete lack of the TCTN in circular and longitudinal muscles was observed. A CTPL was not developed. The children with a hypoperistalsis syndrome had no CTPL, but had a partly-developed TCTN in the circular and longitudinal muscles, which gradually faded in the direction of the plexus layer. Independent of a well-developed enteric nervous system, a lack of the TCTN in longitudinal and circular muscles and a missing CTPL (aplastic desmosis) abolishes the coordinated peristaltic movement of the gut. An isolated lack of the CTPL in the myenteric plexus (hypoplastic desmosis) results in a hypoperistalsis syndrome. An anomaly of the TCTN in the muscularis propria disturbs gut-muscle mechanics, and is another cause of gut dysmotility.

Familial form of hirschsprung disease: nucleotide sequence studies reveal point mutations in the RET proto-oncogene in two of six families but not in other candidate genes.

Hirschsprung disease (HSCR; McKusick 142623) or aganglionic megacolon is a frequent (1 in 5,000 live births) heritable disorder of the enteric nervous system. By haplotyping with a variety of microsatellite markers, by amplifying all 20 exons of the RET proto-oncogene and by applying a direct DNA sequencing protocol, we have analyzed the DNA from HSCR patients in 6 different families. In one family with a joint occurrence of HSCR and FMTC (follicular medullary thyroid carcinoma), we have identified a mutation in codon 609 in one out of 6 cysteine residues encoded in exon 10 of the RET gene. This C609R point mutation has not previously been reported to cause HSCR. In 2 of the HSCR patients described here from different families, we have found a mutation in exon 2 (R77C) and a silent mutation in exon 3 (Y204Y), respectively, in the extracellular part of the RET proto-oncogene. In introns 2 and 17 of the RET proto-oncogene in 2 families, we have detected single nucleotide exchanges that are probably polymorphisms with unknown, if any, relations to HSCR. The DNA sequences of 5 further genes (GDNF, GDNFRalpha, EDN3, EDNRB, and NTN), that may contribute to the development of HSCR, have not shown mutations in the patients analyzed so far. In 2 of the reported families with several affected children and one grandchild, sequence analyses revealed no mutations in the coding regions of any of the candidate genes analyzed.

A new polyurethane anal plug in the treatment of incontinence after anal atresia repair.

UNLABELLED: 38 totally or partially incontinent patients following imperforate anus repair (age 6-15 years) tested a new polyurethane (PU) anal plug against another, widely used anal plug (PVA) in a randomized crossover trial. Plugs were tested 3 weeks each, data concerning bowel habits, handling and plug-related problems were collected by questionnaire before trial, at time of product change and after trial. RESULTS: 15 of 38 patients did not complete the protocol, among them 6 with anal canal diameters too small for the smallest plug. During plug use, patients experienced enhanced awareness of repletion and urge. Stool consistence did not change in 82% of patients. There were no changes in children constipated prior to study (n = 8/23). 12,123 children were absolutely clean during use of either plug. 15 patients (68%) using the PU plug and 10 (45%) using the PVA plug felt secure from soiling during plug use. 74% of patients preferred the PU plug. Painful plug insertion, a feeling of pressure inside the anal canal and painful plug removal were reported with both plugs, but were less frequent with the PU plug. CONCLUSION: Anal plugs, regardless of their make, offer absolute cleanliness for periods of several hours to 66% of our incontinent patients. The PU plug (Conveen, Coloplast) is preferred by the patients and offers greater security than the PVA plug.

Neurological phenotype in Waardenburg syndrome type 4 correlates with novel SOX10 truncating mutations and expression in developing brain.

Waardenburg syndrome type 4 (WS4), also called Shah-Waardenburg syndrome, is a rare neurocristopathy that results from the absence of melanocytes and intrinsic ganglion cells of the terminal hindgut. WS4 is inherited as an autosomal recessive trait attributable to EDN3 or EDNRB mutations. It is inherited as an autosomal dominant condition when SOX10 mutations are involved. We report on three unrelated WS4 patients with growth retardation and an as-yet-unreported neurological phenotype with impairment of both the central and autonomous nervous systems and occasionally neonatal hypotonia and arthrogryposis. Each of the three patients was heterozygous for a SOX10 truncating mutation (Y313X in two patients and S251X [corrected] in one patient). The extended spectrum of the WS4 phenotype is relevant to the brain expression of SOX10 during human embryonic and fetal development. Indeed, the expression of SOX10 in human embryo was not restricted to neural-crest-derived cells but also involved fetal brain cells, most likely of glial origin. These data emphasize the important role of SOX10 in early development of both neural-crest-derived tissues, namely melanocytes, autonomic and enteric nervous systems, and glial cells of the central nervous system.

Histopathologic observations of anorectal abnormalities in anal atresia.

Over the years from 1992 to 1997, 41 anorectal malformations (ARM) with histopathologic alterations were investigated to determine which morphologic abnormalities of the distal rectum accompany ARMs. Three other cases showed normal neuromuscular morphology; 9 further cases could not be evaluated owing to scanty biopsies. All resected specimens were caudocranially coiled and cryostat cut at -20 degrees C into serial sections, which were stained with a lactic dehydrogenase, succinic dehydrogenase, nitroxide synthase, and acetylcholinesterase reaction as well as hemalum and sirius red. Ten low, 15 intermediate, and 10 high forms of anal atresia (AA) were studied. In addition, six cloacal abnormalities were investigated. In 7 cases (17%) (5 intermediate, 2 low AAs), the characteristics of Hirschsprung's disease were observed. Oligoneuronal hypoganglionosis of the myenteric plexus proximal to the anal floor was diagnosed in 7 AAs (12%). In 10 children with high-type AA and resection of 1-5 cm distal rectum and in all cloacal anomalies (n = 6) defects of the muscularis propria were seen in the rectal-atresia sac. These defects were characterized by hypoplasia of the circular-muscle layer and/or the internal anal sphincter (IAS). Intestinal neuronal dysplasia of the submucous plexus was most frequently observed (12%) in high-type AA. A correlation between innervation anomalies or anomalies of the muscularis propria and the type of fistula could not be seen. In conclusion, all cases with high-type AA and cloacal anomalies were characterized by anomalies of the muscularis propria and/or IAS but this was not the case in intermediate and low-type AAs. Anomalies of the enteric nervous system were diagnosed in 60% of AAs.

Proximal segment histology of resected bowel in Hirschsprung's disease predicts postoperative bowel function.

The authors present an overview of 101 patients operated for Hirschsprung's disease by Rehbein procedure. Special attention is directed to the histomorphological findings in the proximal segment of the resected bowel specimens. A strong link was confirmed between these specific features and postoperative bowel function. A histologically regular proximal bowel segment generally predicted good postoperative bowel function with a constipation rate of 10.5%. In patients with intestinal neuronal dysplasia (IND) of the proximal segment the overall clinical result remained unchanged, although the constipation rate rose to 17.8%. Postoperative bowel function was seriously affected in cases characterized by proximal segment hypoganglionosis with a constipation rate of 23.1% and an additional 7.7% with encopresis. Finally, the distinct group of children with aganglionosis of the proximal segment followed a complicated postoperative course with secondary bowel resections and recurrent episodes of enterocolitis. In addition, the authors state their general observation that histological findings become less important whenever a more extensive resection than left hemicolectomy is required. Discussing the results, guidelines are given to further patient treatment once the particular proximal segment histology is diagnosed.

A correlative morphometric and clinical investigation of hypoganglionosis of the colon in children.

Hypoganglionosis of the myenteric plexus of the colon is not clearly defined and seldom investigated. Colon segments from 15 children with an extended oligoeuronal hypoganglionosis up to the proximal resection end were morphometrically studied and compared to normally innervated colon segments. The study was performed with resected specimens from 7 children with isolated hypoganglionoses, 8 children with a Hirschsprung-associated hypoganglionosis, and 12 colon segments with normal innervation. The resected colon specimens were caudo-cranial coiled. The native tissue was frozen at -80 degrees C on a cryostat carrier and cut at -20 degrees C in 15 microns-thick sections (equivalent to 4-5-micron-thick paraffin sections). The air-dried sections underwent an enzyme-histochemical procedure for an acetylcholinesterase reaction to stain the parasympathetically innervated myenteric plexus. For histological identification and morphometric measurements, ganglia and nerve cells were selectively stained using a lactic dehydrogenase reaction. The morphometric measurements were performed with an optic-electronic image analysis system that determined ganglion size, ganglion distances, nerve cell number per ganglion, and ganglion number per mm colon. The results showed that hypoganglionosis of the myenteric plexus is characterised by a 42% decrease in plexus area and a 55% decrease of the nerve cell number per mm length of colon. The number and area of myenteric ganglia showed a decrease of 59% and a doubling of the ganglion distances. The histopathological diagnosis of a hypoganglionosis of the colon was not necessarily an indication of a chronic constipation, but rather an indication of a disposition for constipation. A chronic constipation is often caused by a long hypoganglionic segment proximal to a resected short Hirschsprung segment.

Ultrastructural features of nerve fascicles and basal lamina abnormalities in Hirschsprung's disease.

Although the pathogenesis of Hirschsprung's disease (HD) is not completely resolved, both the absence of nerve cells and the hypertrophy of nerve fascicles within the aganglionic colonic segment have been attributed to an abnormal intestinal microenvironment. Studies on animal models for HD revealed an altered ultrastructure of ingrowing nerve fascicles and abnormalities of basal laminae (BL). Therefore, the purpose of this study was to examine the ultrastructure of hypertrophied nerve fascicles in human HD with special reference to structural abnormalities of BL. Colonic specimens were obtained from patients with HD (n = 10) and controls (n = 5) and processed for electron-microscopical examination. Hypertrophied nerve fascicles were characterized by a prominent perineural sheath surrounded by large amounts of collagen bundles, a collagen-filled endoneurium, vasa nervorum and abundant glial cells of extraenteric ultrastructure, which were arranged in mono- or oligoaxonal units and frequently displayed different stages of myelination. As these ultrastructural characteristics resembled typical features of extrinsic nerves and were similar to those observed in subserosal nerves, the prominent intramural nerve fascicles were considered to be of extraenteric origin. Most likely their overabundance contributes to the functional obstruction of the terminal colon. Morphological abnormalities of BL encountered in the aganglionic colonic segment consisted of an extensive multilamination of BL surrounding glial processes and an irregular thickening of BL surrounding perineurocytes and smooth muscle cells of the muscularis mucosae. Similar alterations in BL have also been described in inherited peripheral and diabetic autonomic neuropathies and attributed to reactivated schwann cells. Thus, the overproduction of BL material within the hypertrophied nerve fascicles in HD may reflect an increased activity of proliferating glial cells. Since the smooth muscle cells of the muscularis mucosae showed abnormalities of BL similar to those observed in murine models for HD, it is suggestive that also in human HD the aganglionic colon is affected by a disturbed intestinal micro-environment impairing the neuronal colonisation and promoting the ingrowth of extrinsic nerves. The ultrastructurally observed alterations in BL of both neuronal and non-neuronal cells, as well as the increased amount of perineural and endoneural collagen provide further evidence that extracellular matrix components are abnormally distributed and overproduced within the bowel wall of patients affected by HD.