The Irish Experience with Sacrococcygeal Teratomas: Are Type IV Lesions More Common than We Think?

INTRODUCTION: Sacrococcygeal teratomas (SCTs) are rare tumors occurring in approximately 1 in 35,000 to 40,000 live births. The Altman classification is used to describe SCTs. There are four types, with type 1 predominantly external through to type IV which is a presacral, completely internal mass. As far as the authors are aware, this is the first study to focus on type IV SCT lesions. MATERIALS AND METHODS: Using ICD-10-AM (The International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification) codes, we identified all patients in the Republic of Ireland with a diagnosis of SCT from 2004 to 2020. The following information was obtained for each patient: gender, time of diagnosis, clinical presentation, method of diagnosis, Altman classification, biomarkers, age at operation, surgical technique, pathology, recurrence, and age at most recent follow-up. RESULTS: There were 29 patients in total; 23 females (79%) and 6 males (21%). In total, 16 (55%) were diagnosed antenatally, 4 (14%) at less than 1 month, 4 (14%) less than 1 year, 3 (10%) age 2 to 4 years, and 2 (7%) were aged 5 to 12 years. In addition, 22 (76%) were mature teratomas, 2 (7%) immature teratomas, and 5 (17%) were malignant tumors. There were 6 (21%) type I lesions, 9 (30%) type II, 6 (21%) type III, and 8 (28%) type IV lesions. CONCLUSION: In Altman's original 1974 study, type IV lesions were present in 10% of cases. As a result, this is the most frequently quoted figure. Type IV lesions were present in 28% of cases in our study. We propose that type IV lesions may be more common than the current literature suggests and consequently a higher index of suspicion of their presence should be entertained.

Guillain-Barré syndrome after elective lateral lumbar interbody fusion.

Complications following lateral retroperitoneal transpsoas lumbar fusion (LLIF) surgery include femoral nerve apraxia, bowel/bladder injury, ureteral injury, and potentially, as illustrated in this case report, Guillain-Barré syndrome. Guillain-Barré syndrome (GBS) is an autoimmune inflammatory condition that typically presents after infection, or, less frequently, post-operatively. We report a case of GBS following elective lumbar fusion through the lateral retroperitoneal transpsoas approach (LLIF). A 56-year-old patient presented with left lower extremity (LLE) weakness on post-operative day 12. EMG showed bilateral upper extremity muscle recruitment, worse distally. Following a treatment with intravenous immunoglobulin (IVIG), the patient gradually improved, and her condition was favorable at 6-month post-operative follow-up. CSF analysis and EMG should be part of the workup for patients presenting with lower extremity neuropathy following LLIF.

Targeting the mTOR pathway using novel ATP­competitive inhibitors, Torin1, Torin2 and XL388, in the treatment of glioblastoma.

Mechanistic target of rapamycin (mTOR), which functions via two multiprotein complexes termed mTORC1 and mTORC2, is positioned in the canonical phosphoinositide 3­kinase­related kinase (PI3K)/AKT (PI3K/AKT) pathways. These complexes exert their actions by regulating other important kinases, such as 40S ribosomal S6 kinases (S6K), eukaryotic translation initiation factor 4E (elF4E)­binding protein 1 (4E­BP1) and AKT, to control cell growth, proliferation, migration and survival in response to nutrients and growth factors. Glioblastoma (GB) is a devastating form of brain cancer, where the mTOR pathway is deregulated due to frequent upregulation of the Receptor Tyrosine Kinase/PI3K pathways and loss of the tumor suppressor phosphatase and tensin homologue (PTEN). Rapamycin and its analogs were less successful in clinical trials for patients with GB due to their incomplete inhibition of mTORC1 and the activation of mitogenic pathways via negative feedback loops. Here, the effects of selective ATP­competitive dual inhibitors of mTORC1 and mTORC2, Torin1, Torin2 and XL388, are reported. Torin2 exhibited concentration­dependent pharmacodynamic effects on inhibition of phosphorylation of the mTORC1 substrates S6KSer235/236 and 4E­BP1Thr37/46 as well as the mTORC2 substrate AKTSer473 resulting in suppression of tumor cell migration, proliferation and S­phase entry. Torin1 demonstrated similar effects, but only at higher doses. XL388 suppressed cell proliferation at a higher dose, but failed to inhibit cell migration. Treatment with Torin1 suppressed phosphorylation of proline rich AKT substrate of 40 kDa (PRAS40) at Threonine 246 (PRAS40Thr246) whereas Torin2 completely abolished it. XL388 treatment suppressed the phosphorylation of PRAS40Thr246 only at higher doses. Drug resistance analysis revealed that treatment of GB cells with XL388 rendered partial drug resistance, which was also seen to a lesser extent with rapamycin and Torin1 treatments. However, treatment with Torin2 completely eradicated the tumor cell population. These results strongly suggest that Torin2, compared to Torin1 or XL388, is more effective in suppressing mTORC1 and mTORC2, and therefore in the inhibition of the GB cell proliferation, dissemination and in overcoming resistance to therapy. These findings underscore the significance of Torin2 in the treatment of GB.

National Rates, Reasons, and Risk Factors for 30- and 90-Day Readmission and Reoperation Among Patients Undergoing Anterior Cervical Discectomy and Fusion: An Analysis Using the Nationwide Readmissions Database.

STUDY DESIGN: Retrospective cohort study of the Nationwide Readmissions Database (NRD). OBJECTIVE: To determine causes of and independent risk factors for 30- and 90-day readmission in a cohort of anterior cervical discectomy and fusion (ACDF) patients. SUMMARY OF BACKGROUND DATA: Identifying populations at high-risk of 30-day readmission is a priority in healthcare reform so as to reduce cost and patient morbidity. However, among patients undergoing ACDF, nationally-representative data have been limited, and have seldom described 90-day readmissions, early reoperation, or socioeconomic influences. METHODS: We queried the NRD, which longitudinally tracks 49.3% of hospitalizations, for all adult patients undergoing ACDF. We calculated the rates of, and determined reasons for, readmission and reoperation at 30 and 90 days, and determined risk factors for readmission at each timepoint. RESULTS: We identified 50,126 patients between January and September 2014. Of these, 2294 (4.6%) and 4152 (8.3%) were readmitted within 30 and 90 days of discharge, respectively, and were most commonly readmitted for infections, medical complications, and dysphagia. The characteristics most strongly associated with readmission were Medicare or Medicaid insurance, length of stay greater than or equal to 4 days, three or more comorbidities, and non-routine discharge, whereas surgical factors (e.g., greater number of vertebrae fused) were more modest. By 30 and 90 days, 8.2% and 11.7% of readmitted patients underwent an additional spinal procedure, respectively. CONCLUSION: Our analysis uses the NRD to thoroughly characterize readmission in the general ACDF population. Readmissions are often delayed (after 30 days), strongly associated with insurance status, and many result in reoperation. Our results are crucial for risk-stratifying future ACDF patients and developing interventions to reduce readmission.Level of Evidence: 3.

Femoral hernias: A paediatric surgical enigma.

PURPOSE: In the paediatric population, femoral hernia (FH) represents an uncommon and often misdiagnosed pathology. This study aimed to review our experience with the management of FH in children. METHODS: Medical records were retrospectively reviewed for all patients presenting to the paediatric surgical service in Ireland over a 15-year period (2004-2019), who were operated on for FH. Collected data included demographics, preoperative diagnosis, operative details, complications and follow-up. RESULTS: During the study period, n = 26 patients (n = 18 males) underwent FH repair, with a median age at surgery 6.9 years (range 3-16 years). During the same period n = 5693 patients underwent inguinal herniotomy, resulting in a FH to inguinal hernia (IH) ratio of 1:219 and a FH incidence of 0.45% of all groin hernias. The right side was affected in n = 18 (69.2%) cases and all cases were unilateral. A correct preoperative diagnosis was established in n = 16 (61.5%) cases, n = 8 (30.8%) cases were misdiagnosed as IH and the diagnosis was equivocal in 2 cases (7.7%). All operations were performed on an elective basis. In 3 patients from the misdiagnosed group, FH was found at first operation following negative groin exploration for IH. The remaining 5 patients underwent previous groin exploration for suspected IH and represented with clinical picture of groin hernia recurrence. All patients with a correct preoperative diagnosis underwent a FH repair via an inguinal or infra-inguinal approach. The content of the hernia sac was preperitoneal fat in n = 18 cases, lymph nodes in n = 2 cases, omentum in n = 1 and an empty sac in n = 1. There were no postoperative complications or recurrences. Median follow-up time was 6 weeks (range 0-2.5 years). CONCLUSION: In the paediatric population, FH is a rare pathology and can be a challenging diagnosis. FH is commonly misdiagnosed as IH and may require more than one operation to correctly identify and treat. A high index of suspicion of FH should be maintained in patients who have a negative groin exploration for IH in the setting of a clear pre-operative diagnosis of a groin hernia. FH should also be considered in the differential diagnosis when an IH appears to recur.

Medical alert card: a valuable tool in the management of Hirschsprung's-associated enterocolitis from parental perspective.

PURPOSE: Awareness of Hirschsprung's-associated enterocolitis (HAEC) among patient's families and medical staff can lead to prompt recognition of symptoms and earlier implementation of management. We designed an HAEC medical alert card to raise awareness of HAEC among medical staff and carers of children with Hirschsprung's disease (HD). Our aim was to investigate parental opinion on the utility of this tool. METHODS: All patients diagnosed with HD in two institutions over a period of 14 years received an HAEC alert card and were invited to answer a 1-year follow-up structured questionnaire. RESULTS: A total of 123 patients received an HAEC card. The response rate for the follow-up questionnaire was 62% (n = 76). The majority 96% (n = 73) of the responders considered the card useful. A total of 89% (n = 68) of patients or parents stated that they carry the card with them, while 39% (n = 30) of them have used it on 57 occasions. The majority (83%; n = 25) of these declared that, when presented, the card increased awareness among medical staff and on 53% (n = 16) occasions prompted contact with the tertiary centre. CONCLUSION: The HAEC medical card was found useful by most parents of HD patients. This tool increased awareness of HAEC and improved communication between peripheral hospitals and tertiary paediatric institutions. Therefore, we feel the HAEC alert card may be used in institutions with high HD addressability.

Epidermoid Cyst of the Lumbar Spine After Lumbar Puncture: A Clinical, Radiographic, and Pathologic Correlation.

BACKGROUND: Epidermoid cysts can rarely arise as a late complication of lumbar puncture. We describe a young man who had a remote history of a lumbar puncture and who was subsequently found to have a lumbar spinal epidermoid cyst on imaging, after presenting with lower extremity radicular pain. CASE DESCRIPTION: A 24-year-old man with a remote history of lumbar puncture presented with lower back pain and radicular leg pain which had been ongoing for over a year. Despite conservative management, the patient's symptoms progressed to worsening back pain and left L4 radiculopathy. Magnetic resonance imaging of the lumbar spine demonstrated a peripherally enhancing, intradural, extramedullary lesion at L4-5. Diffusion-weighted imaging revealed diffusion restriction within the lesion, characteristic of an epidermoid cyst. The patient underwent an L4-5 laminectomy for resection of the intradural tumor. The lesion was noted to contain pearly white granules consistent with the appearance of an epidermoid cyst. Histopathology confirmed the diagnosis. On follow-up examination, the patient demonstrated improvement of his back pain and resolution of radicular symptoms. CONCLUSIONS: Lumbar spinal epidermoid cysts may be either congenital or secondary to an iatrogenic cause. This patient had a remote history of lumbar puncture during workup for meningitis as a child. As a complication of a lumbar puncture, the formation of an epidermoid cyst can occur and is thought to be the result of implanted cutaneous tissue. This case provides a comprehensive illustration of the clinical, radiographic, intraoperative, and pathologic findings consistent with an iatrogenic epidermoid cyst.

The Extent of the Transition Zone in Hirschsprung Disease.

BACKGROUND: Retained transition zone is a leading cause of obstructive symptoms after pull-through operation in Hirschsprung's disease. OBJECTIVE: We aimed to evaluate the extent of the histological transition zone in patients with Hirschsprung's disease. DESIGN: We performed an observational study. DAB+ immunohistochemistry for Protein Gene Product 9.5 was used to evaluate the neuronal networks in serial sections of pull-through specimens obtained from children with Hirschsprung's disease (n = 12). Reference ranges for ganglion size/density and nerve trunk diameter were statistically determined using healthy controls obtained from colostomy specimens from children with anorectal malformations (n = 8). The transition zone was defined as ganglionic bowel exhibiting ganglion hypoplasia, hypertrophic nerve trunks, or partial circumference aganglionosis. RESULTS: The mean submucosal nerve trunk diameter in controls was 19.56 µm +/- 3.87 µm. The median age at pull-through for Hirschsprung's disease was 5 months (3-14 months). The median length of the transition zone across the population was 8 cm (4-22 cm). Median transition zone extent was significantly longer in patients with long-segment aganglionosis (n = 6) compared to rectosigmoid aganglionosis (n = 6, 13 cm vs 6 cm, p = 0.041). Due to the age of the patients enrolled, long-term follow-up of bowel function is not yet available. CONCLUSION: Our data suggest that, in children with rectosigmoid Hirschsprung's disease, the transition zone can extend for up to 13 cm. In children with long-segment disease, a longer transition zone is possible. Extended resection at a minimum 5 cm beyond the most distal ganglionic intra-operative biopsy and intra-operative histological examination of the proximal resection margin are required to minimize transition zone pull-through. LEVEL OF EVIDENCE: 2.

Colectomies in children with inflammatory bowel disease: a national referral centre experience.

OBJECTIVES: Few studies have reported on the utility and efficacy of laparoscopic colectomy in the paediatric population. We aim to compare the characteristics and outcomes of children with inflammatory bowel disease (IBD) who underwent open vs laparoscopic treatment at our centre. METHODS: A 10-year retrospective review was performed. Collected data included demographics, indication for surgery, operative characteristics, histopathology results, post-operative course and peri-operative complications. RESULTS: A total of 58 patients underwent subtotal colectomy for IBD, with 38 laparoscopic procedures. The cohort included 33 males and 25 females with a mean age at surgery of 12.9 ± 3.3 years. The pre-operative diagnosis was ulcerative colitis in n = 41, Crohn's disease in n = 5 and indeterminate colitis in n = 11. There was an 84.2% concordance between the pre-operative and the post-operative histological diagnoses. Overall, 34 (58.6%) patients had complications, of which 19 (32.7%) patients required return to theatre. The complication rate was significantly smaller for laparoscopic compared to open procedures (42.1% vs 75%) as well as for elective compared with emergency colectomies (38.4% vs 75%). Four patients (10.5%) required conversion to open approach. CONCLUSIONS: Laparoscopic approach is feasible and safe in most paediatric patients with IBD and has a lower complication rate and better recovery than open procedures, especially when performed in an elective setting.

A Novel Technique for Prevention of Subarachnoid-Pleural Fistula After Incidental Durotomy During Transthoracic Spinal Surgery.

BACKGROUND: Subarachnoid-pleural fistulas (SPFs) are rare but significant complications of transthoracic spinal surgery. Whether noted intraoperatively or in the postoperative period, SPF requires implementation of aggressive management, with consideration given to direct surgical repair. Additionally, the physical constraints of the thoracic cavity often hinder direct SPF repair. OBJECTIVE: To present a novel operative technique that can be used to easily and quickly address incidental durotomy incurred during transthoracic spinal surgery while working within the confines of the thorax. METHODS: Surgical hemostatic clips were used to affix a patch-graft of dural substitute to the parietal pleura surrounding the site of a transthoracic spinal decompression in which an incidental durotomy was incurred. The patch-graft was augmented with the application of biological glue and was successful in preventing symptomatic SPF. RESULTS: The use of surgical clips to affix a patch graft is a quick, easy, and effective means of addressing an incidental durotomy during thoracotomy and preventing SPF. The clip applier is significantly easier to maneuver within the narrow working channel of the thorax than are instruments used during direct repair. CONCLUSION: Preventing SPF can be challenging. The physical constraints of the thoracic cavity make water-tight repair difficult and time-consuming, particularly when the morphology of the dural tear prevents primary apposition of the defect. The authors present a novel technique of preventing development of SPF using hemostatic clips to simply and quickly affix suturable dural substitute to the parietal pleura overlying the site of an incidental durotomy.

Adolescent de novo hydroceles - should they be dealt with by inguinal or scrotal approach?

AIM: The objective of this study was to investigate the optimal approach for the treatment of hydroceles in adolescents. MATERIALS AND METHODS: A retrospective chart review of all adolescents (10-16 years old) diagnosed with a de-novo hydrocele in 2 tertiary care institutions over a 10 year period (2007-2016) was performed comparing the inguinal and trans-scrotal (Jaboulay) approaches. RESULTS: Fifty-three boys with a mean age of 13.4 years (range 10-16 years) were diagnosed with hydrocele. The inguinal approach was used in 31 (59%) patients for treatment of their hydrocele. In 19 (61%) of these cases a patent processus vaginalis (PPV) ligation was performed. In the other 12 (39%) patients the PPV was closed or not found and a further repair of the hydrocele through the same inguinal incision was performed. A transcrotal Jaboulay procedure was performed in 22 (41%) of the patients. There was no difference in the complications rate between inguinal and trans-scrotal approaches (p = 0.71). Age of presentation less than 12 years was associated with the presence of a PPV (p < 0.05). CONCLUSIONS: A trans-scrotal approach should be considered as first-line in adolescents when the history is not suggestive of a communicating hydrocele. Children less than 12 years of age are more likely to have a PPV and an inguinal approach may be more appropriate. TYPE OF STUDY: Retrospective comparative study LEVEL OF EVIDENCE: Level II.

Managing the Complex Patient with Degenerative Cervical Myelopathy: How to Handle the Aging Spine, the Obese Patient, and Individuals with Medical Comorbidities.

Degenerative cervical myelopathy (DCM) is the most common cause of nontraumatic spinal cord injury worldwide. Even relatively mild impairment in functional scores can significantly impact daily activities. Surgery is an effective treatment for DCM, but outcomes are dependent on more than technique and preoperative neurologic deficits.

A Comparative Study of Three Different Types of Stem Cells for Treatment of Rat Spinal Cord Injury.

Three different sources of human stem cells-bone marrow-derived mesenchymal stem cells (BM-MSCs), neural progenitors (NPs) derived from immortalized spinal fetal cell line (SPC-01), and induced pluripotent stem cells (iPSCs)-were compared in the treatment of a balloon-induced spinal cord compression lesion in rats. One week after lesioning, the rats received either BM-MSCs (intrathecally) or NPs (SPC-01 cells or iPSC-NPs, both intraspinally), or saline. The rats were assessed for their locomotor skills (BBB, flat beam test, and rotarod). Morphometric analyses of spared white and gray matter, axonal sprouting, and glial scar formation, as well as qPCR and Luminex assay, were conducted to detect endogenous gene expression, while inflammatory cytokine levels were performed to evaluate the host tissue response to stem cell therapy. The highest locomotor recovery was observed in iPSC-NP-grafted animals, which also displayed the highest amount of preserved white and gray matter. Grafted iPSC-NPs and SPC-01 cells significantly increased the number of growth-associated protein 43 (GAP43+) axons, reduced astrogliosis, downregulated Casp3 expression, and increased IL-6 and IL-12 levels. hMSCs transiently decreased levels of inflammatory IL-2 and TNF-α. These findings correlate with the short survival of hMSCs, while NPs survived for 2 months and matured slowly into glia- and tissue-specific neuronal precursors. SPC-01 cells differentiated more in astroglial phenotypes with a dense structure of the implant, whereas iPSC-NPs displayed a more neuronal phenotype with a loose structure of the graft. We concluded that the BBB scores of iPSC-NP- and hMSC-injected rats were superior to the SPC-01-treated group. The iPSC-NP treatment of spinal cord injury (SCI) provided the highest recovery of locomotor function due to robust graft survival and its effect on tissue sparing, reduction of glial scarring, and increased axonal sprouting.

Expression of connexin 26 and connexin 43 is reduced in Hirschsprung's disease.

BACKGROUND: Despite having an optimal pull-through operation, some children with Hirschsprung's disease (HSCR) continue to experience persistent bowel symptoms. Coordinated colonic electrical activity depends on intercellular communication between the enteric nerves, interstitial cells of Cajal (ICCs), smooth muscle cells, and fibroblast-like (platelet-derived growth factor receptor-alpha-positive) cells. Gap junctions are low-resistance channels composed of connexin (Cx) proteins which couple cells electrically and chemically. We aimed to evaluate the expression patterns of Cx26, Cx36, and Cx43 in the colon of children with HSCR and in healthy control colon. MATERIALS AND METHODS: Entire resected colonic specimens were collected from children undergoing pull-through surgery for HSCR (n = 10). Colonic controls were collected at colostomy closure in children with imperforate anus (n = 8). Distribution of Cx26, Cx36, and Cx43 was assessed using double-labeled immunofluorescence and confocal microscopy. Protein expression was quantified using Western blot analysis. RESULTS: Sparse punctate Cx36 expression was seen in the myenteric plexus in nerve trunks and some platelet-derived growth factor receptor-alpha-positive cell and ICC fibers. Cx26 was similarly distributed, although it was not coexpressed in ICCs. Cx43 was only coexpressed with ICCs in the myenteric plexus. Expression of Cx26 and Cx43 was markedly reduced in the aganglionic colon in HSCR compared to controls, while Cx26 expression was also moderately reduced in the ganglionic bowel in HSCR. CONCLUSIONS: Reduced expression of Cx26 and Cx43 is implicated in the pathophysiology of colonic dysmotility in the aganglionic bowel as well as, in the case of Cx26, the ganglionic bowel in HSCR.

Spinal Cord Compression Secondary to Extramedullary Hematopoiesis: Case Report and Review of the Literature.

Extramedullary hematopoiesis (EMH) is a rare cause of spinal cord compression (SCC). EMH represents the growth of blood cells outside of the bone marrow and occurs in a variety of hematologic illnesses, including various types of anemia and myeloproliferative disorders. Although EMH usually occurs in the liver, spleen, and lymph nodes, it may also occur within the spinal canal. When this occurs, the mass effect can compress the spinal cord, potentially leading to the development of neurological deficits. We present a case of SCC secondary to EMH. This report illustrates the importance of considering EMH in the differential diagnosis of SCC, even in the absence of signs of its most common etiologies.

Successful Treatment of Complex Regional Pain Syndrome with Pseudoaneurysm Excision and Median Nerve Neurolysis.

BACKGROUND: Complex regional pain syndrome (CRPS), formerly referred to as reflex sympathetic dystrophy, is a pain syndrome characterized by severe pain, altered autonomic and motor function, and trophic changes. CRPS is usually associated with soft tissue injury or trauma. It has also been described as a rare complication of arterial access for angiography secondary to pseudoaneurysm formation. CASE DESCRIPTION: A 73-year-old woman underwent catheterization of the left brachial artery for angiography of the celiac artery. The following day, the patient noticed numbness and severe pain in the median nerve distribution of the left upper extremity. Over the next 6 months, the patient developed CRPS in the left hand with pain and signs of autonomic dysfunction. Further work-up revealed the formation of a left brachial artery pseudoaneurysm with impingement on the median nerve. She underwent excision of the pseudoaneurysm with decompression and neurolysis of the left median nerve. Approximately 6 weeks after surgery, the patient had noticed significant improvement in autonomic symptoms. CONCLUSIONS: This case involves a unique presentation of CRPS caused by brachial artery angiography and pseudoaneurysm formation. In addition, the case demonstrates the efficacy of pseudoaneurysm excision and median nerve neurolysis in the treatment of CRPS as a rare complication of arterial angiography.

Altered tryptophan hydroxylase 2 expression in enteric serotonergic nerves in Hirschsprung's-associated enterocolitis.

AIM: To determine if expression of colonic tryptophan hydroxylase-2 (TPH2), a surrogate marker of neuronal 5-hydroxytryptamine, is altered in Hirschsprung's-associated enterocolitis. METHODS: Entire resected colonic specimens were collected at the time of pull-through operation in children with Hirschsprung's disease (HSCR, n = 12). Five of these patients had a history of pre-operative Hirschsprung's-associated enterocolitis (HAEC). Controls were collected at colostomy closure in children with anorectal malformation (n = 10). The distribution of expression of TPH2 was evaluated using immunofluorescence and confocal microscopy. Protein expression of TPH2 was quantified using western blot analysis in the deep smooth muscle layers. RESULTS: TPH2 was co-expressed in nitrergic and cholinergic ganglia in the myenteric and submucosal plexuses in ganglionic colon in HSCR and healthy controls. Co-expression was also seen in submucosal interstitial cells of Cajal and PDGFRα(+) cells. The density of TPH2 immuno-positive fibers decreased incrementally from ganglionic bowel to transition zone bowel to aganglionic bowel in the myenteric plexus. Expression of TPH2 was reduced in ganglionic bowel in those affected by pre-operative HAEC compared to those without HAEC and healthy controls. However, expression of TPH2 was similar or high compared to controls in the colons of children who had undergone diverting colostomy for medically refractory HAEC. CONCLUSION: Altered TPH2 expression in colonic serotonergic nerves of patients with HSCR complicated by HAEC may contribute to intestinal secretory and motor disturbances, including recurrent HAEC.

Altered neurotransmitter expression profile in the ganglionic bowel in Hirschsprung's disease.

PURPOSE: Despite having optimal pull-through (PT) surgery for Hirschsprung's disease (HSCR), many patients experience persistent bowel symptoms with no mechanical/histopathological cause. Murine models of HSCR suggest that expression of key neurotransmitters is unbalanced proximal to the aganglionic colonic segment. We aimed to investigate expression of key enteric neurotransmitters in the colon of children with HSCR. METHODS: Full-length PT specimens were collected fresh from children with HSCR (n=10). Control specimens were collected at colostomy closure from children with anorectal malformation (n=8). The distributions of neuronal nitric oxide synthase (nNOS), choline acetyltransferase (ChAT), vasoactive intestinal peptide (VIP), and substance P (SP) were evaluated using immunofluorescence and confocal microscopy. Neurotransmitter quantification was with Western blot analysis. RESULTS: ChAT expression was high in aganglionic bowel and transition zone but reduced in ganglionic bowel in HSCR relative to controls. Conversely, nNOS expression was markedly reduced in aganglionic bowel but high in ganglionic bowel in HSCR relative to controls. VIP expression was similar in ganglionic HSCR and control colon. SP expression was similar in all tissue types. CONCLUSION: Imbalance of key excitatory and inhibitory neurotransmitters in the ganglionic bowel in HSCR may explain the basis of bowel dysmotility after an optimal pull-through operation in some patients.

Use of anoctamin 1 (ANO1) to evaluate interstitial cells of Cajal in Hirschsprung's disease.

PURPOSE: Interstitial cells of Cajal (ICCs) are pacemaker cells involved in facilitating neurotransmission and the generation of slow electrical waves necessary for colonic peristalsis. Their distribution has been found to be abnormal in the aganglionic and ganglionic colon in Hirschsprung's disease (HSCR) using c-kit-labelling. Anoctamin-1 (ANO1) is a Ca(2+)-activated Cl(-) channel thought to be specifically expressed on ICCs. Unlike c-kit, it plays a key role in ICC pacemaker activity. We aimed to investigate the utility of ANO1 in evaluating the colonic ICC network in HSCR. MATERIALS AND METHODS: We collected full-length pull-through specimens from children with HSCR (n = 10). Control colon specimens were collected at colostomy closure in children with anorectal malformation (n = 6). The distribution of ANO1 and c-kit expression was evaluated using immunofluorescence and confocal microscopy. ANO1 expression was quantified using Western blot analysis. RESULTS: ANO1 was not expressed on 23 % of c-kit immuno-positive cells in the circular muscle; however, 100 % of ANO1-positive ICCs were c-kit positive. The distribution of ANO1-positive ICCs was sparse in aganglionic colon, with a modest reduction in ICCs seen in the ganglionic colon in HSCR compared to controls (p = 0.044). ANO1 protein expression was reduced in aganglionic colon but similar in ganglionic colon relative to controls. CONCLUSIONS: ANO1 is preferential to c-kit in evaluating the ICC network in HSCR due to its specificity and functional importance. Abnormal distribution of ANO1-positive ICCs in the ganglionic colon in HSCR may contribute to persistent bowel symptoms in some patients after pull-through surgery.