Enzymhistochemie des klassischen und des ultrakurzen Morbus Hirschsprung

Cholinergic Signaling Attenuates Pro-Inflammatory Interleukin-8 Response in Colonic Epithelial Cells

Infants affected by Hirschsprung disease (HSCR), a neurodevelopmental congenital disorder, lack ganglia of the intrinsic enteric nervous system (aganglionosis) in a variable length of the colon, and are prone to developing severe Hirschsprung-associated enterocolitis (HAEC). HSCR patients typically show abnormal dense innervation of extrinsic cholinergic nerve fibers throughout the aganglionic rectosigmoid. Cholinergic signaling has been reported to reduce inflammatory response. Consequently, a sparse extrinsic cholinergic innervation in the mucosa of the rectosigmoid correlates with increased inflammatory immune cell frequencies and higher incidence of HAEC in HSCR patients. However, whether cholinergic signals influence the pro-inflammatory immune response of intestinal epithelial cells (IEC) is unknown. Here, we analyzed colonic IEC isolated from 43 HSCR patients with either a low or high mucosal cholinergic innervation density (fiber-low versus fiber-high) as well as from control tissue. Compared to fiber-high samples, IEC purified from fiber-low rectosigmoid expressed significantly higher levels of IL-8 but not TNF-α, IL-10, TGF-β1, Muc-2 or tight junction proteins. IEC from fiber-low rectosigmoid showed higher IL-8 protein concentrations in cell lysates as well as prominent IL-8 immunoreactivity compared to IEC from fiber-high tissue. Using the human colonic IEC cell line SW480 we demonstrated that cholinergic signals suppress lipopolysaccharide-induced IL-8 secretion via the alpha 7 nicotinic acetylcholine receptor (a7nAChR). In conclusion, we showed for the first time that the presence of a dense mucosal cholinergic innervation is associated with decreased secretion of IEC-derived pro-inflammatory IL-8 in the rectosigmoid of HSCR patients likely dependent on a7nAChR activation. Owing to the association between IL-8 and enterocolitis-prone, fiber-low HSCR patients, targeted therapies against IL-8 might be a promising immunotherapy candidate for HAEC treatment.

Lack of Mucosal Cholinergic Innervation Is Associated With Increased Risk of Enterocolitis in Hirschsprung's Disease

BACKGROUND & AIMS

Hirschsprung's disease (HSCR) is a congenital intestinal motility disorder defined by the absence of enteric neuronal cells (ganglia) in the distal gut. The development of HSCR-associated enterocolitis remains a life-threatening complication. Absence of enteric ganglia implicates innervation of acetylcholine-secreting (cholinergic) nerve fibers. Cholinergic signals have been reported to control excessive inflammation, but the impact on HSCR-associated enterocolitis is unknown.

METHODS

We enrolled 44 HSCR patients in a prospective multicenter study and grouped them according to their degree of colonic mucosal acetylcholinesterase-positive innervation into low-fiber and high-fiber patient groups. The fiber phenotype was correlated with the tissue cytokine profile as well as immune cell frequencies using Luminex analysis and fluorescence-activated cell sorting analysis of colonic tissue and immune cells. Using confocal immunofluorescence microscopy, macrophages were identified in close proximity to nerve fibers and characterized by RNA-seq analysis. Microbial dysbiosis was analyzed in colonic tissue using 16S-rDNA gene sequencing. Finally, the fiber phenotype was correlated with postoperative enterocolitis manifestation.

RESULTS

The presence of mucosal nerve fiber innervation correlated with reduced T-helper 17 cytokines and cell frequencies. In high-fiber tissue, macrophages co-localized with nerve fibers and expressed significantly less interleukin 23 than macrophages from low-fiber tissue. HSCR patients lacking mucosal nerve fibers showed microbial dysbiosis and had a higher incidence of postoperative enterocolitis.

CONCLUSIONS

The mucosal fiber phenotype might serve as a prognostic marker for enterocolitis development in HSCR patients and may offer an approach to personalized patient care and new therapeutic options.

Disruption of the network between Onuf's nucleus and myenteric ganglia, and developing Hirschsprung-like disease following spinal subarachnoid haemorrhage: an experimental study

Purpose/Aim of the study: Auerbach/Meissner network of lower abdominopelvic organs managed by parasympathetic nerve fibres of lumbosacral roots arising from Onuf's nucleus located in conus medullaris. Aim of this study is to evaluate if there is any relationship between Onuf's nucleus ischemia and Auerbach/Meissner network degeneration following spinal subarachnoid haemorrhage (SAH). Materials and Methods: Study was conducted on 24 male rabbits included control (Group I, n = 5), serum saline-SHAM (Group II, n = 5), and spinal SAH (Group III, n = 14) groups. Spinal SAH performed by injecting homologous blood into subarachnoid space at Th₁₂-L₄ level and followed three weeks. Live and degenerated neuron densities of Onuf's nucleus, Auerbach and Meissner ganglia (n/mm³) were determined by Stereological methods. Results: The mean degenerated neuron density of Onuf's nucleus was significantly higher in Group III than in Groups I-II (152 ± 26, 2 ± 1 and 5 ± 2/mm³ respectively, p < 0.005). The degenerated neuron density of Auerbach's ganglia was significantly higher in Group III than in Groups I-II (365 ± 112, 3 ± 1 and 9 ± 3/mm³ respectively, p < 0.005). The degenerated neuron density of Meissner's ganglia was significantly higher in Group III than in Groups I-II (413 ± 132, 2 ± 1 and 11 ± 4/mm³ respectively, p < 0.005). Conclusions: Onuf's nucleus pathologies should be considered as Auerbach/Meissner ganglia degeneration and also related Hirschsprung-like diseases in the future.

Hirschsprung Disease - Current Diagnosis and Management

Hirschsprung disease is a common cause of neonatal and infantile large gut obstruction. It is characterised by varying extent of contiguous aganglionosis extending from the anorectum proximally. Since its recognition, the diagnosis and management has continuously evolved with advances in histological evaluation and surgical techniques. This article summarizes the current modalities of investigation and optimal surgical management of Hirschsprung disease and concludes with a reference to the Indian scenario.

Hirschsprung disease in the older child: diagnostic strategies

BACKGROUND

Hirschsprung disease is usually diagnosed in patients who are younger than 1 year; but in some individuals it is found later in childhood.

OBJECTIVE

This retrospective study is focused on clinical signs and symptoms of Hirschsprung disease in older children.

MATERIALS AND METHODS

Patients with Hirschsprung disease were included in the study if they were older than 14 months at the time of diagnosis.

RESULTS

Ten patients older than 14 months were diagnosed with Hirschsprung disease; 7 were males and 3 females. In all, 60% had a positive history of recurrent gastrointestinal infection with vomiting and hospitalization. In 6 patients, the final diagnosis was delayed because of unspecific findings in contrast enema. Rectal biopsy confirmed the diagnosis in all patients.

CONCLUSION

Contrast enema is not a specific method for diagnosing Hirschsprung disease. Rectal biopsy alone confirms the diagnosis and provides a clear indication for surgery.

[Twenty years diagnostic competence center for Hirschsprung's disease in Basel]

BACKGROUND

The experience gained by the Basel Hirschsprung Competence Center over 20 years is presented.

MATERIALS AND METHODS

A total of 19,365 rectal mucosal biopsies were investigated in the 20 years between 1987 and 2006. All biopsies of rectal mucosa originated from 6,615 children aged between 1 week and 4 years. Biopsies were collected in teaching hospitals all over Germany and transported on dry ice by Intercity Courier Service. Serial sections of frozen tissue were made using a cryostat. Enzyme histochemical staining was performed.

RESULTS

A total of 935 cases of Hirschsprung's disease (14%) were observed (769 cases of classical Hirschsprung's disease, 68 total colon aganglionosis, 98 ultrashort rectum aganglionosis). Total colon aganglionosis was found in 1.0% and the frequency of ultrashort Hirschsprung' disease was 1.4%. The quality of the histological results was confirmed by a second independent investigator. There were neither false positive nor false negative diagnoses. Enzyme histochemical staining results were readable within 2 h. Acetylcholinesterase, which is significantly increased in Hirschsprung's disease, was used for nerve fiber staining. Succinic and lactic dehydrogenases and nitric oxide synthase served as confirmatory proof of aganglionosis (elective nerve cell staining of the submucous plexus).

CONCLUSION

Among 100 children with chronic constipation an average of 12 children were diagnosed with Hirschsprung's disease. Of these 2% showed total colon aganglionosis or ultrashort Hirschsprung's disease. Enzyme histochemical diagnosis of Hirschsprung's disease proved 100% reliable and time saving.