Optimization of tracheoesophageal fistula model established with T-shaped magnet system based on magnetic compression technique.

BACKGROUND: The magnetic compression technique has been used to establish an animal model of tracheoesophageal fistula (TEF), but the commonly shaped magnets present limitations of poor homogeneity of TEF and poor model control. We designed a T-shaped magnet system to overcome these problems and verified its effectiveness via animal experiments. AIM: To investigate the effectiveness of a T-shaped magnet system for establishing a TEF model in beagle dogs. METHODS: Twelve beagles were randomly assigned to groups in which magnets of the T-shaped scheme (study group, n = 6) or normal magnets (control group, n = 6) were implanted into the trachea and esophagus separately under gastroscopy. Operation time, operation success rate, and accidental injury were recorded. After operation, the presence and timing of cough and the time of magnet shedding were observed. Dogs in the control group were euthanized after X-ray and gastroscopy to confirm establishment of TEFs after coughing, and gross specimens of TEFs were obtained. Dogs in the study group were euthanized after X-ray and gastroscopy 2 wk after surgery, and gross specimens were obtained. Fistula size was measured in all animals, and then harvested fistula specimens were examined by hematoxylin and eosin (HE) and Masson trichrome staining. RESULTS: The operation success rate was 100% for both groups. Operation time did not differ between the study group (5.25 min ± 1.29 min) and the control group (4.75 min ± 1.70 min; P = 0.331). No bleeding, perforation, or unplanned magnet attraction occurred in any animal during the operation. In the early postoperative period, all dogs ate freely and were generally in good condition. Dogs in the control group had severe cough after drinking water at 6-9 d after surgery. X-ray indicated that the magnets had entered the stomach, and gastroscopy showed TEF formation. Gross specimens of TEFs from the control group showed the formation of fistulas with a diameter of 4.94 mm ± 1.29 mm (range, 3.52-6.56 mm). HE and Masson trichrome staining showed scar tissue formation and hierarchical structural disorder at the fistulas. Dogs in the study group did not exhibit obvious coughing after surgery. X-ray examination 2 wk after surgery indicated fixed magnet positioning, and gastroscopy showed no change in magnet positioning. The magnets were removed using a snare under endoscopy, and TEF was observed. Gross specimens showed well-formed fistulas with a diameter of 6.11 mm ± 0.16 mm (range, 5.92-6.36 mm), which exceeded that in the control group (P < 0.001). Scar formation was observed on the internal surface of fistulas by HE and Masson trichrome staining, and the structure was more regular than that in the control group. CONCLUSION: Use of the modified T-shaped magnet scheme is safe and feasible for establishing TEF and can achieve a more stable and uniform fistula size compared with ordinary magnets. Most importantly, this model offers better controllability, which improves the flexibility of follow-up studies.

Case report of radiotherapy combined with anlotinib and immunotherapy for a patient with esophageal cancer and esophageal fistula.

BACKGROUND: Esophageal cancer (EC) is a frequent gastrointestinal malignancy. The most common types of EC pathology worldwide are esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC). Although surgical resection is still the main treatment modality for EC, most patients are already lost to surgery at the time of presentation due to the late stage. In recent years, the development of radiation therapy (RT) combined with targeted therapy (TT) and immunization therapy (IT) has brought more options for the treatment of EC. During radiation therapy, the radiation therapy area is very close to the trachea and esophagus, so radiation therapy may cause damage to the tissues of the trachea and esophagus, which is also known as a tracheoesophageal fistula (TF). We present the case of an EC patient who developed TF during radiation therapy and gradually improved after a combination of anlotinib and immunotherapy. METHODS: The patient was diagnosed with poorly differentiated ESCC by pathological biopsy and treated with "lobaplatin + Tegafur Gimeracil Oteracil Porassium Capsule" for 5 cycles. RESULTS: CT scan of the chest showed progression after treatment. During RT, the patient developed radiotherapy-related adverse effects, which were relieved by symptomatic support therapy. At the end of RT, the patient developed TF, but we chose to let the patient continue his radiation treatment plan with the anti-angiogenic drug "anlotinib." CONCLUSION: After radiation therapy, the patient continued to be treated with anlotinib and immunotherapy with camrelizumab, and the patient's lesion improved.

Magnetic Resonance Imaging-Based Evaluation of Anatomy and Outcome Prediction in Infants with Esophageal Atresia.

INTRODUCTION: There is currently no validated diagnostic modality to characterize the anatomy and predict outcomes of tracheal esophageal defects, such as esophageal atresia (EA) and tracheal esophageal fistulas (TEFs). We hypothesized that ultra-short echo-time MRI would provide enhanced anatomic information allowing for evaluation of specific EA/TEF anatomy and identification of risk factors that predict outcome in infants with EA/TEF. METHODS: In this observational study, 11 infants had pre-repair ultra-short echo-time MRI of the chest completed. Esophageal size was measured at the widest point distal to the epiglottis and proximal to the carina. Angle of tracheal deviation was measured by identifying the initial point of deviation and the farthest lateral point proximal to the carina. RESULTS: Infants without a proximal TEF had a larger proximal esophageal diameter (13.5 ± 5.1 mm vs. 6.8 ± 2.1 mm, p = 0.07) when compared to infants with a proximal TEF. The angle of tracheal deviation in infants without a proximal TEF was larger than infants with a proximal TEF (16.1 ± 6.1° vs. 8.2 ± 5.4°, p = 0.09) and controls (16.1 ± 6.1° vs. 8.0 ± 3.1°, p = 0.005). An increase in the angle of tracheal deviation was positively correlated with duration of post-operative mechanical ventilation (Pearson r = 0.83, p < 0.002) and total duration of post-operative respiratory support (Pearson r = 0.80, p = 0.004). DISCUSSION: These results demonstrate that infants without a proximal TEF have a larger proximal esophagus and a greater angle of tracheal deviation which is directly correlated with the need for longer post-operative respiratory support. Additionally, these results demonstrate that MRI is a useful tool to assess the anatomy of EA/TEF.

Quantifying Upper Aerodigestive Sequelae in Esophageal Atresia/Tracheoesophageal Fistula Neonates.

OBJECTIVES: We examined rates of upper aerodigestive tract (UADT) procedures in a multi-institutional cohort of neonates with esophageal atresia/tracheoesophageal fistula (EA/TEF) to estimate secondary UADT pathology. METHODS: A retrospective cohort study was performed using a previously-validated population of patients with EA/TEF within the Pediatric Health Information System (PHIS) between 2007 and 2015. ICD-9/10-CM codes for aerodigestive procedures were examined from 2007 to 2020: 1) diagnostic direct laryngoscopy and/or bronchoscopy (DLB), 2) DLB with intervention, 3) tracheostomy, 4) gastrostomy, 5) fundoplication, 6) aortopexy, 7) laryngotracheoplasty, and 8) esophageal dilation. Associations between procedures and demographics, length of gestation, and weight were estimated using generalized linear mixed models. RESULTS: We identified 2,509 patients with EA/TEF from 47 hospitals, 56.7% male and 43.3% female. Median length of stay for the first admission was 24 days (interquartile range: 12-55). Of these patients, 1,943 (77.4%) had at least one aerodigestive procedure within 14 admissions. Specifically, 1,635 (65.2%) underwent diagnostic DLB, 85 (3.4%) DLB with intervention, 167 (6.7%) tracheostomy, 1,043 (41.2%) gastrostomy, 211 (11.0%) fundoplication, 52 (2.1%) aortopexy, 161 (6.4%) laryngotracheoplasty, and 207 (8.3%) esophageal dilation. Preterm gestation increased odds of tracheostomy (adjusted odds ratio (OR) 2.4, 95% confidence interval (CI) 1.5-3.7), gastrostomy (OR 2.1, CI 1.7-2.7), fundoplication (OR 1.7, CI 1.1-2.4), aortopexy (OR 5.8, CI 2.1-16.1), and esophageal dilation (OR 2.0, CI 1.4-3.0). Very low birth weight (<1,500 g) increased odds of gastrostomy (OR 2.5, CI 1.6-3.8). CONCLUSION: Patients with EA/TEF frequently have aerodigestive sequelae. This work helps quantify aerodigestive needs in neonates with EA/TEF, suggesting early otolaryngology evaluation in their care. LEVEL OF EVIDENCE: 3 Laryngoscope, 132:695-700, 2022.

Heritability and De Novo Mutations in Oesophageal Atresia and Tracheoesophageal Fistula Aetiology.

Tracheoesophageal Fistula (TOF) is a congenital anomaly for which the cause is unknown in the majority of patients. OA/TOF is a variable feature in many (often mono-) genetic syndromes. Research using animal models targeting genes involved in candidate pathways often result in tracheoesophageal phenotypes. However, there is limited overlap in the genes implicated by animal models and those found in OA/TOF-related syndromic anomalies. Knowledge on affected pathways in animal models is accumulating, but our understanding on these pathways in patients lags behind. If an affected pathway is associated with both animals and patients, the mechanisms linking the genetic mutation, affected cell types or cellular defect, and the phenotype are often not well understood. The locus heterogeneity and the uncertainty of the exact heritability of OA/TOF results in a relative low diagnostic yield. OA/TOF is a sporadic finding with a low familial recurrence rate. As parents are usually unaffected, de novo dominant mutations seems to be a plausible explanation. The survival rates of patients born with OA/TOF have increased substantially and these patients start families; thus, the detection and a proper interpretation of these dominant inherited pathogenic variants are of great importance for these patients and for our understanding of OA/TOF aetiology.

Exome survey of individuals affected by VATER/VACTERL with renal phenotypes identifies phenocopies and novel candidate genes.

The acronym VATER/VACTERL refers to the rare nonrandom association of the following component features (CFs): vertebral defects (V), anorectal malformations (ARM) (A), cardiac anomalies (C), tracheoesophageal fistula with or without esophageal atresia (TE), renal malformations (R), and limb anomalies (L). For the clinical diagnosis, the presence of at least three CFs is required, individuals presenting with only two CFs have been categorized as VATER/VACTERL-like. The majority of VATER/VACTERL individuals displays a renal phenotype. Hitherto, variants in FGF8, FOXF1, HOXD13, LPP, TRAP1, PTEN, and ZIC3 have been associated with the VATER/VACTERL association; however, large-scale re-sequencing could only confirm TRAP1 and ZIC3 as VATER/VACTERL disease genes, both associated with a renal phenotype. In this study, we performed exome sequencing in 21 individuals and their families with a renal VATER/VACTERL or VATER/VACTERL-like phenotype to identify potentially novel genetic causes. Exome analysis identified biallelic and X-chromosomal hemizygous potentially pathogenic variants in six individuals (29%) in B9D1, FREM1, ZNF157, SP8, ACOT9, and TTLL11, respectively. The online tool GeneMatcher revealed another individual with a variant in ZNF157. Our study suggests six biallelic and X-chromosomal hemizygous VATER/VACTERL disease genes implicating all six genes in the expression of human renal malformations.

Mammalian tracheal development and reconstruction: insights from in vivo and in vitro studies.

The trachea delivers inhaled air into the lungs for gas exchange. Anomalies in tracheal development can result in life-threatening malformations, such as tracheoesophageal fistula and tracheomalacia. Given the limitations of current therapeutic approaches, development of technologies for the reconstitution of a three-dimensional trachea from stem cells is urgently required. Recently, single-cell sequencing technologies and quantitative analyses from cell to tissue scale have been employed to decipher the cellular basis of tracheal morphogenesis. In this Review, recent advances in mammalian tracheal development and the generation of tracheal tissues from pluripotent stem cells are summarized.

Surgical management of benign cervical tracheoesophageal fistulas: A single-tertiary academic institution experience.

PURPOSE: Despite improvements of diagnosis and management, acquired benign tracheoesophageal fistulas (AB-TEFs) remain a challenging clinical problem and a life-threating condition. In the present study, we reviewed the early results and the long-term outcomes after surgical treatment of cervical AB-TEFs treated in our institution during the last 9 years. METHODS: This retrospective study included patients who underwent transcervical repair of benign cervical AB-TEFs. Patients were identified from a prospectively filled electronic database which included patients' demographics, medical history, disease presentation, prior treatments, operative report, morbidity and mortality, hospital stay, postoperative results and follow-up information. RESULTS: A total of 13 patients affected by cervical AB-TEF were treated. Most of the patients (91%) in our series were treated with a lateral cervicotomic approach with interposition of either sternocleidomastoid muscle flap (72.7%) or pectoralis major myocutaneous flap (9.1%) or infrahyoid muscle flap (9.1%). The univariate analysis of showed that the etiology and surgical technique were significantly associated with immediate postoperative outcome. Esophageal diversion was removed in all patients but 3 due to their neurological status, which was the only significant factor related to post-operative oral-intake (p =0.016). We experienced 2 (18.2%) failures of the reconstruction, which occurred in patients previously treated with chemoradiation for head and neck malignancies. None of the remaining patients (72.8%) relapsed after a long-term follow-up restoring a normal oral diet was restored. CONCLUSION: The lateral cervicotomic approach with sternocleidomastoid flap interposition showed its effectiveness and safety in the treatment of AB-TEFs in our single-institution experience.

Feingold syndrome type 2 in a patient from China.

Feingold syndrome type 2 (FGLDS2, MIM614326) is a genetic congenital malformation syndrome, caused by germline heterozygous deletion of MIR17HG on chromosome 13q31, which is extremely rare worldwide. To date, less than 25 patients have been described in the literature. Here, we report on a 3-year-old girl presented with hip dysplasia, polysyndactyly of the left thumb, brachymesophalangy of the fifth digit, microcephaly, intellectual disability, and growth delay. This is likely to be the first case of Feingold syndrome type 2 ever discovered among Chinese population. Through genetic testing and pedigree analysis, she was identified to have a de novo 4.8-Mb microdeletion at chromosome 13q31.3-q32.1, encompassing MIR17HG, GPC5, and GPC6. Additionally, we detected two common compound heterozygous variants (c.919-2A>G and c.147C>G) in SLC26A4 encoding pendrin protein, as well as a novel heterozygous variant c.985_988del in COMP encoding cartilage oligomeric matrix protein. This case report aims to analyze the microdeletion and the three types of variant detected in the patient, and to explore the association between the genotype and phenotype in patients with Feingold syndrome type 2, which may contribute to further understanding and future diagnosis of this disorder.

Clinical and molecular characterizations of 11 new patients with type 1 Feingold syndrome: Proposal for selecting diagnostic criteria and further genetic testing in patients with severe phenotype.

Feingold Syndrome type 1 (FS1) is an autosomal dominant disorder due to a loss of function mutations in the MYCN gene. FS1 is generally clinically characterized by mild learning disability, microcephaly, short palpebral fissures, short stature, brachymesophalangy, hypoplastic thumbs, as well as syndactyly of toes, variably associated with organ abnormalities, the most common being gastrointestinal atresia. In current literature, more than 120 FS1 patients have been described, but diagnostic criteria are not well agreed upon, likewise the genotype-phenotype correlations are not well understood. Here, we describe 11 FS1 patients, belonging to six distinct families, where we have identified three novel MYCN mutations along with three pathogenetic variants, the latter which have already been reported. Several patients presented a mild phenotype of the condition and they have been diagnosed as being affected only after segregation analyses of the MYCN mutation identified in the propositus. We also describe here the first ever FS1 patient with severe intellectual disability having a maternally inherited MYCN variant together with an additional GNAO1 mutation inherited paternally. Mutations in the GNAO1 gene are associated with a specific form of intellectual disability and epilepsy, thus the finding of two different rare diseases in the same patient could explain his severe phenotype. Therein, a thorough investigation is merited into the possibility that additional variants in patients with a MYCN mutation and severe phenotype do exist. Finally, in order to guarantee a more reliable diagnosis of FS1, we suggest using both major and minor clinical-molecular diagnostic criteria.

Thoracoscopic repair of esophageal atresia with distal tracheoesophageal fistula: is it a safe procedure in infants weighing less than 2000 g?

BACKGROUND: Since Rothenberg first performed thoracoscopic repair for esophageal atresia with distal tracheoesophageal fistula (EA/TEF) successfully in 2000, thoracoscopic repair has achieved status as a routine procedure worldwide. Previously, an international multicenter study reported that this procedure was not inferior to conventional open surgery. However, thoracoscopic surgery is a highly difficult operation for surgeons and anesthesiologists; as a result, the safety and efficacy of the surgery is still under debate. Considering these circumstances, the purpose of this study was to analyze the results of single-center thoracoscopic surgery and to compare the outcomes relative to the patient's weight at the time of surgery. METHODS: We retrospectively analyzed patients with EA/TEF who underwent thoracoscopic surgery in a single center between October 2008 and February 2017. RESULTS: In total, 41 cases of thoracoscopic repair of EA/TEF were performed. Upon subgrouping by over and under 2000 g of body weight at the time of operation, 34 were found to be over 2000 g and seven were under 2000 g. Intraoperative factors and events were not significantly different between the two groups. Additionally, most of the postoperative outcomes, including the rate of postoperative leakage and strictures, showed no difference. On the other hand, the under 2000 g group had more gastroesophageal reflux requiring fundoplication than did the heavier group (P = 0.04). CONCLUSIONS: The results of this center's thoracoscopic repair of EA/TEF were not inferior to other centers' outcomes. Additionally, the intraoperative and postoperative outcomes were similar despite differences in weight at operation. Therefore, thoracoscopic repair might be a feasible surgical option for infants weighing less than 2000 g when performed by a surgeon and anesthesiologist team who are experienced in pediatric thoracoscopic surgery.

Histological, immunohistochemical and transcriptomic characterization of human tracheoesophageal fistulas.

Esophageal atresia (EA) and tracheoesophageal fistula (TEF) are relatively frequently occurring foregut malformations. EA/TEF is thought to have a strong genetic component. Not much is known regarding the biological processes disturbed or which cell type is affected in patients. This hampers the detection of the responsible culprits (genetic or environmental) for the origin of these congenital anatomical malformations. Therefore, we examined gene expression patterns in the TEF and compared them to the patterns in esophageal, tracheal and lung control samples. We studied tissue organization and key proteins using immunohistochemistry. There were clear differences between TEF and control samples. Based on the number of differentially expressed genes as well as histological characteristics, TEFs were most similar to normal esophagus. The BMP-signaling pathway, actin cytoskeleton and extracellular matrix pathways are downregulated in TEF. Genes involved in smooth muscle contraction are overexpressed in TEF compared to esophagus as well as trachea. These enriched pathways indicate myofibroblast activated fibrosis. TEF represents a specific tissue type with large contributions of intestinal smooth muscle cells and neurons. All major cell types present in esophagus are present-albeit often structurally disorganized-in TEF, indicating that its etiology should not be sought in cell fate specification.

Muscle Flap Transposition for the Management of Intrathoracic Fistulas.

BACKGROUND: Intrathoracic fistulas pose unique challenges for thoracic and reconstructive surgeons. To decrease the incidence of fistula recurrence, pedicled flaps have been suggested to buttress the repair site. The authors aimed to report their experience with muscle flap transposition for the management of intrathoracic fistulas. METHODS: A retrospective review of all patients who underwent intrathoracic muscle flap transposition for the management of intrathoracic fistulas from 1990 to 2010 was conducted. Patient demographics, surgical characteristics, and complication rates were abstracted and analyzed. RESULTS: A total of 198 patients were identified. Bronchopleural fistula was present in 156 of the patients (79 percent), and 48 had esophageal fistula (24 percent). A total of 238 flaps were used, constituting an average of 1.2 flaps per patient. After the initial fistula repair, bronchopleural fistula complicated the course of 34 patients (17 percent), and esophageal fistula occurred in 13 patients (7 percent). Partial flap loss was identified in 11 flaps (6 percent), and total flap loss occurred in four flaps (2 percent). Median follow-up was 27 months. At the last follow-up, 182 of the patients (92 percent) had no evidence of fistula, 175 (89 percent) achieved successful chest closure, and 164 (83 percent) had successful treatment. Preoperative radiation therapy and American Society of Anesthesiologists score of 4 or greater were identified as risk factors for unsuccessful treatment. CONCLUSIONS: Intrathoracic fistulas remain a source of major morbidity and mortality. Reinforcement of the fistula closure with vascularized muscle flaps is a viable option for preventing dehiscence of the repair site and can be potentially life-saving. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Transition Zone in Total Colonic Aganglionosis and Colorectal Hirschsprung's Disease Shows a Similar Trend of Mucosal Innervation: Image Processing and Analysis Study.

The aganglionic segment of bowel in Hirschsprung's disease (HD) varies in length. It is not clear whether total colonic aganglionosis (TCA) merely represents a long form of HD or a different phenotype of the disease. Animal model studies suggest that TCA may have a longer transition zone (TZ) than conventional colorectal HD. We compared mucosal innervation of TZ in 2 TCA cases and 10 conventional colorectal HD cases by quantifying calretinin-positive mucosal nerve fibers using image processing and analysis. One TCA was associated with esophageal atresia-tracheoesophageal fistula, the other with trisomy 21. The gradients of calretinin-stained pixel count increase per distance from the beginning of TZ (slope) for TCA were not significantly different from those for the conventional HD group. Given this observation, it is speculated that the length of TZ in TCA may fall within the range of and may not be much longer than conventional colorectal HD.

An Unusual Lung Mass of Heterotopic Pancreatic Tissue in a Neonate With an Elevated Immunoreactive Trypsinogen on Newborn Screen.

We present a case of a neonate with tracheoesophageal fistula and esophageal atresia along with a suspicious lung mass who had a false-positive newborn screen for cystic fibrosis due to an elevated serum immunoreactive trypsinogen with an additionally elevated serum lipase. The infant's lung mass was found to contain heterotopic pancreatic tissue consisting of acini, ducts, and islet cells, without an associated gastrointestinal duplication cyst. This constellation of congenital abnormalities has not been described in previous literature. Also, this is the first reported case of a neonate with elevated serum pancreatic enzymes in which the underlying etiology was discovered to be heterotopic pancreas.

Novel magnetic compression technique for establishment of a canine model of tracheoesophageal fistula.

BACKGROUND: Clinically, tracheoesophageal fistula (TEF) is lack of effective surgical strategies. One reason is due to the lack of appropriate animal models of acquired TEF, which is usually complex and difficult. Recently, the magnetic compression technique has been applied for digestive tract anastomosis or vascular anastomosis in animals. In this study, an animal model of TEF in dogs was developed by using the magnetic compression technique, hoping to provide a new method for mimicking TEF. AIM: To establish a TEF model in dogs by using the magnetic compression technique. METHODS: Six male beagles were used as models with two Nd-Fe-B permanent magnets for TEF. The parent magnet and the daughter magnet were placed in the cervical esophagus and trachea, respectively. The anterior wall of the esophagus and the posterior wall of the trachea were compressed when the two magnets coupled. After 4-6 d, the necrotic tissue between the two magnets fell off and the parent and daughter magnets disengaged from the target location, leaving a fistula. Gastroscopy/bronchoscopy, upper gastrointestinal contrast study, and histological analysis were performed. RESULTS: The establishment of the TEF model in all six beagles was successful. The average time of magnet placement was 4.33 ± 1.11 min (range, 3-7 min). Mean time for the magnets to disengage from the target location was 4.67 ± 0.75 d (range, 4-6 d). TEFs were observed by gastroscopy/bronchoscopy and esophageal angiography. The gross anatomical structure of the esophagus and the trachea was in good condition. There was no esophageal mucosa or pseudostratified ciliated columnar epithelium at the site of the fistula according to histological analysis. CONCLUSION: It is simple, feasible, and minimally invasive to use the magnetic compression technique for the establishment of the TEF model in dogs.