Comprehensive characterization of the genetic landscape of familial Hirschsprung's disease

Analysis of the causes of redo pull-through for recurrent constipation and the risk factors affecting the prognosis of the Hirschsprung's disease: a single-center retrospective study and systematic review

BACKGROUND

Hirschsprung's disease (HSCR) is a congenital gastrointestinal disorder. Pull-through (PT) surgery, the primary treatment, often leads to recurrent constipation. The causes of redo pull-through (redo-PT) for recurrent constipation remain unclear, with limited research on follow-up outcomes and prognostic factors.

METHODS

We searched "PubMed" and "Web of Science" for references using the title/abstract terms "Hirschsprung" and "Redo pull-through". We enrolled patients from the literature review group and our retrospective group who underwent redo-PT for recurrent constipation. A comparative analysis was conducted between two groups based on the clinical information for redo-PT.

RESULTS

A total of 360 cases were collected from the references (327 patients) and our center (33 patients). Recurrent aganglionosis (RA) and Mechanical Obstruction (MO) were the primary reasons for redo-PT, accounting for 52.50% and 36.67%, respectively. When comparing the causes of redo-PT between the literature group and our center group, RA accounted for 49.85% and 75.76%, while MO accounted for 49.85% and 21.21%, respectively. Prognostic outcomes of 31 patients from our center were analyzed, revealing no significant associations between postoperative complications and gender, age, causes of redo pull-through, or surgical approach (P > 0.05).

CONCLUSIONS

Recurrent constipation requiring redo-PT are predominantly caused by RA and MO. Gender, age, causes of redo pull-through, or surgical approach do not affect the prognosis of redo-PT. The laparoscopic approach demonstrated superior cosmetic outcomes compared to the laparotomy approach.

Rare and common genetic variants underlying the risk of Hirschsprung's disease

Hirschsprung's disease (HSCR) is a congenital enteric neuropathic disorder characterized by high heritability (>80%) and polygenic inheritance (>20 genes). The previous genome-wide association studies (GWAS) identified several common variants associated with HSCR and demonstrated increased predictive performance for HSCR risk in Europeans using a genetic risk score, there remains a notable gap in knowledge regarding Chinese populations. We conducted whole exome sequencing in a HSCR case cohort in Chinese. By using the common controls (505 controls from 1KG EAS and 10 588 controls from ChinaMAP), we conducted GWAS for the common variants in the exome and gene-based association for rare variants. We further validated the associated variants and genes in replicated samples and in vitro and vivo experiments. We identified one novel gene PLK5 by GWAS and suggested 45 novel putative genes based the gene-based test. By using genetic variant at RET and PLK5, we constructed a genetic risk score that could identify the individuals with very high genetic risk for HSCR. Compared with patients with zero or one risk allele from the three variants, the risk for HSCR was 36.61 times higher with six alleles. In addition, we delineated a HSCR risk gene landscape that encompasses 57 genes, which explains 88.5% and 54.5% of HSCR in Chinese and European, respectively. In summary, this study improved the understanding of genetic architecture of HSCR and provided a risk prediction approach for HSCR in the Chinese.

Scientific evolution from the definition of Hirschsprung disease to the present: a bibliometric analysis (1980-2023)

BACKGROUND

The primary objective of this study is to define the global productivity of Hirschsprung disease (HSCR), identify influential studies, determine research directions focused on both historical and contemporary perspectives.

METHODS

The study obtained 2816 articles published between 1980 and 2023 related to HSCR from the Web of Science database, and comprehensive bibliometric analysis were conducted.

RESULTS

The top three most productive countries were the USA (n = 1283), China (n = 1167), and Japan (n = 587). The most productive institution was Université Paris Cité (n = 149), and the most productive author was Prem Puri (n = 99). The most frequently used keywords in the articles were enterocolitis (n = 191), enteric nervous system (n = 136), and transanal endorectal pull-through (n = 129).

CONCLUSION

Academic interest in HSCR began in 1887-1888, significantly increased in 1948 and 1964, and reached its highest peak in 1994. The findings indicate that key topics such as enterocolitis, enteric nervous system, surgical techniques, and genetic factors have been prominent in HSCR research. Previous studies, which often focused on molecular and genetic mechanisms, have shifted towards clinical and surgical applications in the last decade. Factor analysis reveals the complexity and diversity of HSCR research, with various topics examined, including clinical features, surgical treatments, pathological findings, and genetic bases.

IMPACT STATEMENT

This study presents a comprehensive bibliometric analysis of global research trends and future directions in Hirschsprung disease, revealing significant changes and developments in the study of the disease. The study provides an important contribution to the existing literature by detailing the historical development, main research topics, and thematic evolution of Hirschsprung disease research. The findings indicate that future research focus in Hirschsprung disease may increasingly prioritize innovative approaches, such as stem cell therapy, alongside clinical and surgical advancements. These advancements have the potential to enhance patient quality of life and guide future research strategies.

Cinchophen induces RPA1 related DNA damage and apoptosis to impair ENS development of zebrafish

Nonsteroidal anti-inflammatory drugs (NSAIDs) have become contaminants widely distributed in the environment due to improper disposal and discharge. Previous study has found several components might involve in impairing enteric nervous system (ENS) development of zebrafish, including NSAIDs cinchophen. Deficient ENS development in fetal could lead to Hirschsprung disease (HSCR), a congenital neurocristopathy characterized by absence of enteric neurons in hindgut. However, the intrinsic mechanism of neurotoxicity of cinchophen is unclear. We confirmed that cinchophen could impair ENS development of zebrafish and transcriptome sequencing revealed that disfunction of Replication protein A1 (RPA1), which is involved in DNA replication and repairment, might be relevant to the neurotoxicity effects induced by cinchophen. Based on previous data of single cell RNA sequencing (scRNA-seq) of zebrafish gut cells, we observed that rpa1 mainly expressed in proliferating, differentiating ENS cells and neural crest progenitors. Interestingly, cinchophen induced apoptosis and impaired proliferation. Furthermore, cinchophen caused DNA damage and abnormal activation of ataxia telangiectasia mutated/ Rad3 related (ATM/ATR) and checkpoint kinase 2 (CHK2). Finally, molecular docking indicated cinchophen could bind and antagonize RPA1 more effectively. Our study might provide a better understanding and draw more attention to the role of environmental factors in the pathogenesis of HSCR. And the mechanism of cinchophen neurotoxicity would give theoretical guidance for clinical pharmacy.

Diagnostic accuracy of barium enema versus full-thickness rectal biopsy in children with clinically suspected Hirschsprung's disease: A comparative cross-sectional study

Background and Aims

Hirschsprung's disease (HSD) remains a common cause of pediatric intestinal obstruction. Barium contrast enema (BE) is the primary imaging modality for the evaluation of clinically suspected cases. Here, we aimed to assess the diagnostic accuracy of BE in children with clinically suspected HSD when compared to a gold standard full-thickness rectal biopsy (FTRB).

Methods

We recruited and consecutively enrolled children with clinically suspected HSD at two tertiary teaching hospitals. Participants underwent BE imaging and two radiologists interpreted the findings independently. Participants further underwent FTRB by pediatric surgeons as the confirmatory test. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristics (ROC) with the area under the curve (AUC) were calculated on Stata version 14.2, taking FTRB as the standard.

Results

We enrolled 55 cases, of which 49 completed the evaluation and were included in the final analysis. The median age was 9.4 months (interquartile range: 2-24], with a male-to-female ratio of 4.4:1. The sensitivity, specificity, PPV, and NPV of BE were 0.95 (95% confidence interval [CI] [0.81-0.99]), 0.73 (95% CI [0.39-0.94]), 0.92 (95% CI [0.82-0.97]), and 0.80 (95% CI [0.50-0.94]), respectively. On AUC, the diagnostic accuracy of BE compared to the confirmatory FTRB was 0.84 (95% CI [0.69-0.98]). The diagnostic accuracy was higher in neonates (ROC: 1.00) when compared to infants (ROC: 0.83) or those above 1 year of age (ROC: 0.798). HSD-suggestive BE findings were associated with absence of ganglion cells on FTRB (χ 2 = 23.301, p < 0.001). Inverted rectosigmoid ratio and transition zone were more sensitive in detecting HSD of 0.92 (95% CI [0.74-0.98]) and 0.81 (95% CI [0.63-0.92]), respectively.

Conclusion

BE is sufficiently accurate in the diagnosis of children with HSD, suggesting BE would likely be used to inform surgical management in settings where confirmatory biopsy is lacking. However, clinical judgment is warranted in interpreting negative BE findings.

Hirschsprung disease

Hirschsprung disease (HSCR) is a rare congenital intestinal disease that occurs in 1 in 5,000 live births. HSCR is characterized by the absence of ganglion cells in the myenteric and submucosal plexuses of the intestine. Most patients present during the neonatal period with the first meconium passage delayed beyond 24 h, abdominal distension and vomiting. Syndromes associated with HSCR include trisomy 21, Mowat-Wilson syndrome, congenital central hypoventilation syndrome, Shah-Waardenburg syndrome and cartilage-hair hypoplasia. Multiple putative genes are involved in familial and isolated HSCR, of which the most common are the RET proto-oncogene and EDNRB. Diagnosis consists of visualization of a transition zone on contrast enema and confirmation via rectal biopsy. HSCR is typically managed by surgical removal of the aganglionic bowel and reconstruction of the intestinal tract by connecting the normally innervated bowel down to the anus while preserving normal sphincter function. Several procedures, namely Swenson, Soave and Duhamel procedures, can be undertaken and may include a laparoscopically assisted approach. Short-term and long-term comorbidities include persistent obstructive symptoms, enterocolitis and soiling. Continued research and innovation to better understand disease mechanisms holds promise for developing novel techniques for diagnosis and therapy, and improving outcomes in patients.

Abnormally elevated expression of ACTA2 of circular smooth muscle leads to hyperactive contraction in aganglionic segments of HSCR

BACKGROUND

Actin Alpha 2 (ACTA2) is expressed in intestinal smooth muscle cells (iSMCs) and is associated with contractility. Hirschsprung disease (HSCR), one of the most common digested tract malformations, shows peristaltic dysfunction and spasm smooth muscles. The arrangement of the circular and longitudinal smooth muscle (SM) of the aganglionic segments is disorganized. Does ACTA2, as a marker of iSMCs, exhibit abnormal expression in aganglionic segments? Does the ACTA2 expression level affect the contraction function of iSMCs? What are the spatiotemporal expression trends of ACTA2 during different developmental stages of the colon?

METHODS

Immunohistochemical staining was used to detect the expression of ACTA2 in iSMCs of children with HSCR and Ednrb-/- mice, and the small interfering RNAs (siRNAs) knockdown technique was employed to investigate how Acta2 affected the systolic function of iSMCs. Additionally, Ednrb-/- mice were used to explore the changes in the expression level of iSMCs ACTA2 at different developmental stages.

RESULTS

The expression of ACTA2 is higher in circular SM in the aganglionic segments of HSCR patients and Ednrb-/- mice than in normal control children and mice. Down regulation of Acta2 weakens the contraction ability of intestinal smooth muscle cells. Abnormally elevated expression of ACTA2 of circular smooth muscle occurs since embryonic day 15.5 (E15.5d) in aganglionic segments of Ednrb-/- mice.

CONCLUSIONS

Abnormally elevated expression of ACTA2 in the circular SM leads to hyperactive contraction, which may cause the spasm of aganglionic segments in HSCR.