Diagnostic Accuracy of Serum Matrix Metalloproteinase-7 for Biliary Atresia

Development of a diagnostic model for biliary atresia based on MMP7 and serological tests using machine learning

OBJECTIVE

To develop a machine learning diagnostic model based on MMP7 and other serological testing indicators for early and efficient diagnosis of biliary atresia (BA).

METHODS

A retrospective analysis was conducted on patient information from those hospitalized for pathological jaundice at Beijing Children's Hospital between January 1, 2019, and December 31, 2023. Patients with serum MMP7, liver stiffness measurements, and other routine serological tests were included in the study. Six machine learning models were constructed, including logistic regression (LR), random forest (RF), decision tree (DET), support vector machine classifier (SVC), neural network (MLP), and extreme gradient boosting (XGBoost), to diagnose BA. The area under the receiver operating characteristic curve was used to evaluate the diagnostic efficacy of the various models.

RESULTS

A total of 98 patients were included in the study, comprising 64 BA patients and 34 patients with other cholestatic liver diseases. Among the six machine learning models, the XGBoost algorithm model and RF algorithm model achieved the best predictive performance, with an AUROC of nearly 100% in both the training and validation sets. In the training set, these two algorithm models achieved an accuracy, precision, recall, F1 score, and AUROC of 1. Through model interpretation analysis, serum MMP7 levels, serum GGT levels, and acholic stools were identified as the most important indicators for diagnosing BA. The nomogram constructed based on the XGBoost algorithm model also demonstrated convenient and efficient diagnostic efficacy.

CONCLUSION

Machine learning models, especially the XGBoost algorithm and RF algorithm models, constructed based on preoperative serum MMP7 and serological tests can diagnose BA more efficiently and accurately. The most important influencing factors for diagnosis are serum MMP7, serum GGT, and acholic stools.

Serum matrix metalloproteinase-7 for discriminating biliary atresia: a diagnostic accuracy and validation study

BACKGROUND

Prompt and precise differential diagnosis of biliary atresia (BA) among cholestatic patients is of great importance. Matrix metalloproteinase-7 (MMP-7) holds great promise as a diagnostic marker for BA. This study aimed to investigate the accuracy of age-specific serum MMP-7 for discriminating BA from other cholestatic pediatric patients.

METHODS

This was a single center diagnostic accuracy and validation study including both retrospective and prospective cohorts. Serum MMP-7 concentrations were measured using an ELISA kit, the trajectory of which with age was investigated in a healthy infants cohort aged 0 to 365 days without hepatobiliary diseases (n = 284). Clinical BA diagnosis was based on intraoperative cholangiography and subsequent histological examinations. The diagnostic accuracy of age-specific cutoffs of serum MMP-7 were assessed in a retrospective cohort of cholestatic patients (n = 318, with 172 BA) and validated in a prospective cohort (n = 687, including 395 BA).

RESULTS

The MMP-7 concentration declines non-linearly with age, showing higher levels in healthy neonates as well as higher cutoff value in neonatal cholestasis. The area under the ROC curve (AUROC) was 0.967 (95% confidence interval [CI]: 0.946-0.988) for the retrospective cohort, and the cutoff of 18 ng/mL yielded 93.0% (95%CI: 88.1-96.3%), 93.8% (95%CI: 88.6-97.1%), 94.7% (95%CI: 90.1-97.5%), and 91.9% (95%CI: 86.4-95.8%) for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), respectively. The performance of MMP-7 was successfully validated in the larger prospective cohort, resulting in a diagnostic sensitivity of 95.9% (379/395; 95% CI: 93.5-97.7%), a specificity of 87.3% (255/292; 95% CI: 83.0-90.9%), a PPV of 91.1% (379/416; 95% CI: 87.9-93.7%), and a NPV of 94.1% (255/271; 95% CI: 90.6-96.6%), respectively. Besides, higher cutoff value of 28.1 ng/mL achieved the best sensitivity, specificity, PPV, and NPV for infants aged 0-30 days, which was 86.4% (95% CI: 75.0-94.0%), 95.5% (95% CI: 77.2-99.9%), 98.1% (95% CI: 89.7-100%), and 72.4% (95% CI: 52.8-87.3%), respectively.

CONCLUSIONS

The serum MMP-7 is accurate and reliable in differentiating BA from non-BA cholestasis, showing its potential application in the diagnostic algorithm for BA and significant role in the future research regarding pathogenesis of BA.

Diagnostic accuracy of serum matrix metalloproteinase-7 as a biomarker of biliary atresia in a large North American cohort

BACKGROUND AND AIMS

High levels of serum matrix metalloproteinase-7 (MMP-7) have been linked to biliary atresia (BA), with wide variation in concentration cutoffs. We investigated the accuracy of serum MMP-7 as a diagnostic biomarker in a large North American cohort.

APPROACH AND RESULTS

MMP-7 was measured in serum samples of 399 infants with cholestasis in the Prospective Database of Infants with Cholestasis study of the Childhood Liver Disease Research Network, 201 infants with BA and 198 with non-BA cholestasis (age median: 64 and 59 days, p = 0.94). MMP-7 was assayed on antibody-bead fluorescence (single-plex) and time resolved fluorescence energy transfer assays. The discriminative performance of MMP-7 was compared with other clinical markers. On the single-plex assay, MMP-7 generated an AUROC of 0.90 (CI: 0.87-0.94). At cutoff 52.8 ng/mL, it produced sensitivity = 94.03%, specificity = 77.78%, positive predictive value = 64.46%, and negative predictive value = 96.82% for BA. AUROC for gamma-glutamyl transferase = 0.81 (CI: 0.77-0.86), stool color = 0.68 (CI: 0.63-0.73), and pathology = 0.84 (CI: 0.76-0.91). Logistic regression models of MMP-7 with other clinical variables individually or combined showed an increase for MMP-7+gamma-glutamyl transferase AUROC to 0.91 (CI: 0.88-0.95). Serum concentrations produced by time resolved fluorescence energy transfer differed from single-plex, with an optimal cutoff of 18.2 ng/mL. Results were consistent within each assay technology and generated similar AUROCs.

CONCLUSIONS

Serum MMP-7 has high discriminative properties to differentiate BA from other forms of neonatal cholestasis. MMP-7 cutoff values vary according to assay technology. Using MMP-7 in the evaluation of infants with cholestasis may simplify diagnostic algorithms and shorten the time to hepatoportoenterostomy.

A Pilot Study for Biliary Atresia Diagnosis: Fluorescent Imaging of Indocyanine Green in Stool

BACKGROUND

Biliary atresia is the most common cause of obstructive jaundice in infants and conventional cholangiography is the current diagnostic gold standard. Fluorescent cholangiography with indocyanine green can enhance biliary tree visualization during surgery because it is exclusively excreted into the bile ducts and eventually into the intestine. Therefore, we hypothesized that indocyanine green presence in stool could confirm bile duct patency in infants.

METHODS

A prospective single center cohort study was performed on infants (age ≤ 12 months) with and without jaundice after obtaining IRB approval. Indocyanine green was administered intravenously (0.1 mg/kg). Soiled diapers collected post-injection were imaged for fluorescence.

RESULTS

After indocyanine green administration, fluorescence was detected in soiled diapers for control patients (n = 4, x = 14 h22 m post-injection) and jaundiced patients without biliary atresia (n = 11, x = 13 h28 m post-injection). For biliary atresia patients (n = 7), post-injection soiled diapers before and after Kasai portoenterostomy were collected. Fluorescence was not detected in stool from 6 of 7 biliary atresia patients. As a test, indocyanine green detection in stool was 97% accurate for assessing biliary patency.

CONCLUSION

Fluorescent Imaging for Indocyanine Green (FIInd Green) in stool is a fast and accurate approach to assess biliary patency non-invasively in infants.

LEVEL OF EVIDENCE

Level III.

Proteomics Defines Plasma Biomarkers for the Early Diagnosis of Biliary Atresia

Early diagnosis of biliary atresia (BA) is crucial for improving the chances of survival and preserving the liver function of pediatric patients with BA. Herein, we performed proteomics analysis using data-independent acquisition (DIA) and parallel reaction monitoring (PRM) to explore potential biomarkers for the early diagnosis of BA compared to other non-BA jaundice cases. Consequently, we detected and validated differential protein expression in the plasma of patients with BA compared to the plasma of patients with intrahepatic cholestasis. Bioinformatics analysis revealed the enriched biological processes characteristic of BA by identifying the differential expression of specific proteins. Signaling pathway analysis revealed changes in the expression levels of proteins associated with an alteration in immunoglobulin levels, which is indicative of immune dysfunction in BA. The combination of polymeric immunoglobulin receptor expression and immunoglobulin lambda variable chain (IGL c2225_light_IGLV1-47_IGLJ2), as revealed via machine learning, provided a useful early diagnostic model for BA, with a sensitivity of 0.8, specificity of 1, accuracy of 0.89, and area under the curve value of 0.944. Thus, our study identified a possible effective plasma biomarker for the early diagnosis of BA and could help elucidate the underlying mechanisms of BA.

Neurotensin contributes to cholestatic liver disease potentially modulating matrix metalloprotease-7

The diagnosis and treatment of biliary atresia pose challenges due to the absence of reliable biomarkers and limited understanding of its etiology. The plasma and liver of patients with biliary atresia exhibit elevated levels of neurotensin. To investigate the specific role of neurotensin in the progression of biliary atresia, the patient's liver pathological section was employed. Biliary organoids, cultured biliary cells, and a mouse model were employed to elucidate both the potential diagnostic significance of neurotensin and its underlying mechanistic pathway. In patients' blood, the levels of neurotensin were positively correlated with matrix metalloprotease-7, interleukin-8, and liver function enzymes. Neurotensin and neurotensin receptors were mainly expressed in the intrahepatic biliary cells and were stimulated by bile acids. Neurotensin suppressed the growth and increased expression of matrix metalloprotease-7 in biliary organoids. Neurotensin inhibited mitochondrial respiration, oxidative phosphorylation, and attenuated the activation of calmodulin-dependent kinase kinase 2-adenosine monophosphate-activated protein kinase (CaMKK2-AMPK) signaling in cultured biliary cells. The stimulation of neurotensin in mice and cultured cholangiocytes resulted in the upregulation of matrix metalloprotease-7 expression through binding to its receptors, namely neurotensin receptors 1/3, thereby attenuating the activation of the CaMKK2-AMPK pathway. In conclusion, these findings revealed the changes of neurotensin in patients with cholestatic liver disease and its mechanism in the progression of the disease, providing a new understanding of the complex mechanism of hepatobiliary injury in children with biliary atresia.

Clinical Characteristics and Prognosis of Biliary Atresia with Low Serum Matrix Metalloproteinase-7 Levels

PURPOSE

Serum matrix metalloproteinase-7 (MMP-7) levels can precisely differentiate biliary atresia (BA) from non-BA cholestasis. However, serum MMP-7 levels of some BA patients were within normal range or slightly elevated. This study aimed to investigate the clinical characteristics and prognosis of biliary atresia with low serum MMP-7 levels.

METHOD

This is a retrospective cohort study. Cases of BA from July 2020 to December 2022 were consecutively enrolled. They were divided into low-MMP-7 group (MMP-7 ≤ 25 ng/ml) and high-MMP-7 group (MMP-7 > 25 ng/ml) according to serum MMP-7 levels preoperatively. The perioperative clinical characteristics, the 3-month and 6-month jaundice clearance rate post-Kasai procedure, and the native liver survival were compared between the two groups.

RESULTS

A total of 329 cases were included in this study, 40 of which were divided into the low-MMP-7 group. Preoperative GGT and direct bilirubin levels in the low-MMP-7 group were significantly lower than those in the high-MMP-7 group (258.6 U/L, interquartile range [IQR]: 160.4411.6 vs. 406.8 IU/L, IQR: 215,655.0, P = 0.0076; 103.8 μmol/L, IQR: 79.0,121.4 vs. 115.3 μmol/L, IQR: 94,138.8, P = 0.0071), while the gender, the day at surgery and preoperative ALT, AST, TBA, total bilirubin levels showed no significant differences (P > 0.05). The 3-month and 6-month jaundice clearance rate post-Kasai procedure in the low-MMP-7 group were lower than those in the high-MMP-7 group (29.73% vs. 53.09%, P = 0.049; 32.14% vs. 54.73%, P = 0.023). The 1-year native liver survival rate was 29.63% for the low-MMP-7 group and 53.02% for the high-MMP-7 group (P = 0.022).

CONCLUSION

Preoperative clinical characteristics were similar between low-MMP-7 group and high-MMP-7 group, while patients with low serum MMP-7 levels showed worse prognosis, indicating that this might be listed as a new clinical subtype of BA which could contribute to designing new treatment strategies for BA in the future.

STUDY TYPE

Cohort Study.

LEVEL OF EVIDENCE

Level II.

Progress in Biomarkers Related to Biliary Atresia

Biliary atresia (BA) is a congenital cholestatic disease that can seriously damage children's liver function. It is one of the main reasons for liver transplantation in children. Early diagnosis of BA is crucial to the prognosis of patients, but there is still a lack of reliable non-invasive diagnostic methods. Additionally, as some children are in urgent need of liver transplantation, evaluating the stage of liver fibrosis and postoperative native liver survival in children with BA using a straightforward, efficient, and less traumatic method is a major focus of doctors. In recent years, an increasing number of BA-related biomarkers have been identified and have shown great potential in the following three aspects of clinical practice: diagnosis, evaluation of the stage of liver fibrosis, and prediction of native liver survival. This review focuses on the pathophysiological function and clinical application of three novel BA-related biomarkers, namely MMP-7, FGF-19, and M2BPGi. Furthermore, progress in well-known biomarkers of BA such as gamma-glutamyltransferase, circulating cytokines, and other potential biomarkers is discussed, aiming to provide a reference for clinical practice.

Diseases of bile duct in children

Several diseases originate from bile duct pathology. Despite studies on these diseases, certain etiologies of some of them still cannot be concluded. The most common disease of the bile duct in newborns is biliary atresia, whose prognosis varies according to the age of surgical correction. Other diseases such as Alagille syndrome, inspissated bile duct syndrome, and choledochal cysts are also time-sensitive because they can cause severe liver damage due to obstruction. The majority of these diseases present with cholestatic jaundice in the newborn or infant period, which is quite difficult to differentiate regarding clinical acumen and initial investigations. Intraoperative cholangiography is potentially necessary to make an accurate diagnosis, and further treatment will be performed synchronously or planned as findings suggest. This article provides a concise review of bile duct diseases, with interesting cases.

Alterations of gut microbiota in infants with biliary atresia identified by 16S rRNA-sequencing

BACKGROUND

Biliary atresia (BA) is a severe neonatal disease with progressive intra- and extra-hepatic bile ducts inflammation and hepatic fibrosis. Characterization of gut microbiome profiles in infants with biliary atresia can provide valuable information and potential disease biomarkers. Our study aims to explore the relationship between gut microbiota and biliary atresia.

METHODS

16 S ribosomal RNA (rRNA) gene sequencing was carried out to identify the differences in composition and diversity of gut microbiota between infants with BA and healthy subjects. A total of 31 infants with biliary atresia and 20 healthy subjects were recruited.

RESULTS

The composition of gut microbiota in BA group was significantly different with the normal control group (P < 0.05) and the abundance ratio of Klebsiella/Bifidobacterium showed great potential for identification of BA (P < 0.01). In addition, the differential bacterial taxa were involved in lipid and vitamins metabolism.

CONCLUSION

Our results could provide potential non-invasive biomarker for identification of biliary atresia and contribute to the treatment in terms of ameliorating microbiota dysbiosis.

The magnetic resonance imaging and age-adjusted matrix metalloproteinase-7 assist the diagnosis of biliary atresia

BACKGROUND

We investigated the utilities of the liver-to-psoas apparent diffusion coefficient ratios (LTPAR) yielded by diffusion-weighted magnetic resonance imaging (DWMRI) and the age-adjusted serum matrix metalloproteinase-7 (MMP-7) for the diagnosis of biliary atresia (BA) in cholestatic infants.

METHODS

In total, 170 cholestatic infants were recruited, of whom 50 (29.41%) were diagnosed with BA after cholestatic workups. The LTPAR and MMP7 levels were assessed.

RESULTS

The LTPAR was significantly lower in BA infants, and the age-adjusted MMP7 ratio was significantly higher, compared to other cholestatic infants (both p < 0.001). Receiver operating characteristic curve analysis yielded a cutoff > 0.1 ng/mL.day for the age-adjusted MMP-7 ratio, and an LTPAR < 1.01 for the optimal prediction of BA (both p < 0.001). Univariate logistic regression analysis revealed that both an age-adjusted MMP-7 ratio > 0.1 ng/mL.day and an LTPAR < 1.01 were significant predictors of BA among cholestatic infants (odds ratio = 30.98 and 13.28; p < 0.001 and < 0.001, respectively). The significance of the age-adjusted MMP-7 ratio and the LTPAR persisted on multivariate logistic regression analysis after adjusting for sex and the serum gamma-glutamyl transferase level (p < 0.001 and < 0.001, respectively). The negative predictive values (NPVs) for BA were 91.49% and 94.17%, respectively, for the LTPAR and age-adjusted MMP-7 ratio.

CONCLUSION

The age-adjusted MMP-7 ratio and the LTPAR are both significant non-invasive predictors of BA. The consideration of both serum and imaging parameters may enhance BA diagnostic performance in cholestatic infants.

Intrahepatic Cholangiolitis in Cystic Fibrosis (ICCF): An Under-Appreciated Cause of Persistent Cholestasis in Infancy

Liver histology in infants with cystic fibrosis (CF) and persistent cholestasis is seldom reported in detail. We extend previous observation of a distinctive intrahepatic cholangiopathy (ICCF) to 3 additional infants homozygous for CFTR pathological variants and a fourth infant with a heterozygous CFTR variant, summarizing our experience in 10 infants with CFTR variants and persistent cholestasis. Cholangiograms demonstrate abnormal extrahepatic ducts in 2 infants with CF, 1 with uniform dilatation interpreted as a choledochal cyst and the other with narrow patent ducts. Liver histology in 3 CF homozygotes had prominent ductular reaction with a focally destructive cholangiolitis (inflammation of small bile ducts). The CFTR heterozygote had generalized portal edema with ductular reaction and paucity but no cholangitis. Cholestasis slowly subsided in all infants. ICCF is characterized by severe ductular reaction, prominent cholangiocyte injury, and multifocal necrotizing cholangiolitis. Local aggregates of portal ceroid might suggest previous bile leakage from damaged ducts. ICCF in liver biopsies from infants with cystic fibrosis and persistent cholestasis is unrelated to the specific CFTR genotype. Liver biopsy findings and intraoperative cholangiogram help rule out biliary atresia. ICCF is an early manifestation of CF, a likely prototype for pathogenesis of cystic fibrosis liver disease later in life.

Accurate prediction of biliary atresia with an integrated model using MMP-7 levels and bile acids

BACKGROUND

Biliary atresia (BA) is a rare fatal liver disease in children, and the aim of this study was to develop a method to diagnose BA early.

METHODS

We determined serum levels of matrix metalloproteinase-7 (MMP-7), the results of 13 liver tests, and the levels of 20 bile acids, and integrated computational models were constructed to diagnose BA.

RESULTS

Our findings demonstrated that MMP-7 expression levels, as well as the results of four liver tests and levels of ten bile acids, were significantly different between 86 BA and 59 non-BA patients (P < 0.05). The computational prediction model revealed that MMP-7 levels alone had a higher predictive accuracy [area under the receiver operating characteristic curve (AUC) = 0.966, 95% confidence interval (CI): 0.942, 0.989] than liver test results and bile acid levels. The AUC was 0.890 (95% CI 0.837, 0.943) for liver test results and 0.825 (95% CI 0.758, 0.892) for bile acid levels. Furthermore, bile levels had a higher contribution to enhancing the predictive accuracy of MMP-7 levels (AUC = 0.976, 95% CI 0.953, 1.000) than liver test results. The AUC was 0.983 (95% CI 0.962, 1.000) for MMP-7 levels combined with liver test results and bile acid levels. In addition, we found that MMP-7 levels were highly correlated with gamma-glutamyl transferase levels and the liver fibrosis score.

CONCLUSION

The innovative integrated models based on a large number of indicators provide a noninvasive and cost-effective approach for accurately diagnosing BA in children. Video Abstract (MP4 142103 KB).

Expedited Laparoscopic Cholangiogram and Liver Biopsy in the Workup of Biliary Atresia

PURPOSE

Recent studies demonstrate the success of Kasai portoenterostomy for biliary atresia (BA) is linearly related to infant age at time of Kasai. We sought to review the feasibility and safety of laparoscopic needle micropuncture cholangiogram with concurrent core liver biopsy (if needed) for expedited exclusion of BA in patients with direct conjugated hyperbilirubinemia.

METHODS

Expedited laparoscopic cholangiogram and liver biopsy were instituted at our facility for infants with direct hyperbilirubinemia for whom clinical exam and laboratory workup failed to diagnose. A retrospective chart review was performed in infants <1 year with hyperbilirubinemia from 2016 to 2021. Demographics, preoperative evaluation, procedure details, and complications were reviewed.

RESULTS

Two hundred ninety-seven infants with unspecified jaundice were identified, of which, 86 (29%) required liver biopsy. Forty-seven percutaneous liver biopsies were obtained including 8 (17%) in whom BA could not be excluded. Laparoscopic cholangiogram was attempted in 47 infants following basic workup; BA was diagnosed in 22 infants (47%) of which 3 were <18 days old. Biliary patency was demonstrated laparoscopically in 22 of 25 (88%); 3 (12%) required conversion to open cholangiogram. Infants with percutaneous liver biopsy had an average delay of 3 days (range: 2-36) to cholangiogram. Preoperative studies and liver biopsy alone did not reliably exclude the diagnosis of BA.

CONCLUSION

Laparoscopic cholangiogram with liver biopsy is a safe procedure resulting in the confirmation or exclusion of BA in infants. Forty-seven percent of infants who underwent laparoscopic cholangiogram were found to have BA; those who were surgical candidates underwent Kasai during the same operation.

Measurement of MMP-7 in micro-volume peripheral blood: development of dried blood spot approach

Purpose

Serum matrix metalloproteinase-7 (MMP-7) is significant in differentiating biliary atresia (BA). This study aims to develop a new peripheral blood quantitative collection device to detect MMP-7 levels via dried blood spot (DBS).

Methods

This is a diagnostic accuracy test. Serum and DBS MMP-7 concentrations were measured using an ELISA kit. Intraoperative cholangiography and subsequent histological examinations were used to confirm BA diagnoses.

Results

A total of 241 infants with obstructive jaundice were enrolled, among whom 168 were BA. Linear regression showed DBS MMP-7 correlated well with serum MMP-7 (R = 0.93, P < 0.001). The best cut-off value of serum MMP-7 for BA was 25.9 ng/ml, achieving the area under the ROC curve (AUC) of 0.962 (95% CI: 0.941, 0.983), and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 86.9%, 94.5%, 97.3% and 75.8%, respectively. The best cut-off value of DBS MMP-7 for BA was 12.5 ng/ml, achieving the AUC of 0.922 (95% CI: 0.888, 0.956), and the sensitivity, specificity, PPV, and NPV were 86.9%, 89.0%, 94.8%, and 74.7%, respectively. The dried blood spots were intervened under different storage conditions, including 1-5 days at room temperature, 2 or 3 days at 30 °C and 2 or 3 days at 37 °C. The DBS MMP-7 concentration under different storage conditions had good correlation and consistency with that at -80 °C.

Conclusions

Serum and DBS MMP-7 correlate well, both of which have high accuracy in the diagnosis of BA, while the requirements for the storage of DBS are low.

Treatment of Cholestasis in Infants and Young Children

PURPOSE OF REVIEW

Cholestasis is characterized by a conjugated hyperbilirubinemia secondary to impaired bile synthesis, transport, or excretion from the liver. It is always pathologic and can be indicative of an underlying hepatobiliary, genetic, or metabolic disorder, several of which require timely diagnosis to ensure proper management and optimal outcomes. This review provides an overview of the evaluation of cholestasis with a focus on current and emerging treatment strategies.

RECENT FINDINGS

Increased accessibility of next generation sequencing (NGS) allows for utilization of genetic testing early in the diagnostic process. This may alter the clinical algorithm for diagnosis of cholestatic disorders. An enhanced understanding of the underlying pathophysiology may help guide future development of targeted therapies, such as ileal bile acid transporter (IBAT) inhibitors. These were recently approved for treatment of cholestatic pruritus in patients with Alagille syndrome and Progressive Familial Intrahepatic Cholestasis. Current management of cholestasis is aimed at the biochemical consequences of impaired bile flow, including malnutrition, pruritus, and progressive fibrosis. NGS has led to an enhanced understanding of biliary pathology and may guide development of future treatment modalities based on specific gene mutations. Rapid discernment of the underlying etiology is essential as new treatment modalities emerge.

Development and validation of a model for early diagnosis of biliary atresia

BACKGROUND AND AIMS

Early diagnosis of biliary atresia (BA), particularly distinguishing it from other causes of neonatal cholestasis (NC), is challenging. This study aimed to design and validate a predictive model for BA by using the data available at the initial presentation.

METHODS

Infants presenting with NC were retrospectively identified from tertiary referral hospitals and constituted the model design cohort (n = 148); others were enrolled in a prospective observational study and constituted the validation cohort (n = 21). Clinical, laboratory, and abdominal ultrasonographic features associated with BA were assessed. A prediction model was developed using logistic regression and decision tree (DT) analyses.

RESULTS

Three predictors, namely, gamma glutamyl transpeptidase (γGT) level, triangular cord sign (TC sign), and gallbladder abnormalities, were identified as factors for diagnosing BA in multivariate logistic regression, which was used to develop the DT model. The area under the receiver operating characteristic (ROC) curve (AUC) value for the model was 0.905, which was greater than those for γGT level, TC sign, or gallbladder abnormalities alone in the prediction of BA.

CONCLUSION

A simple prediction model combining liver function and abdominal ultrasonography findings can provide a moderate and early estimate of the risk of BA in patients with NC.

Assessment of Matrix Metalloprotease - 7 (MMP7) Immunohistochemistry in Biliary Atresia and Other Pediatric Cholestatic Liver Diseases

Background and aims: Biliary atresia (BA) is a progressive fibro-obliterative cholangiopathy. The histopathological diagnosis is often challenging and an immunohistochemical marker is often sought as an adjunct. We evaluated MMP7 immunohistochemistry in BA and other non-BA pediatric cholestatic liver diseases. Materials and methods: MMP7 immunohistochemistry was applied in 5 age-matched normal control, 23 cases of BA and 43 cases of non-BA pediatric cholestasis including 16 cases of choledochal cyst (CC), and a multiplication score was obtained by multiplying the intensity and percentage positivity in the cholangiocytes. Results: BA showed a high mean MMP7 multiplication score which was significantly different from the normal control and other non-BA pediatric cholestatic diseases including CC (p value < 0.001). The sensitivity, specificity, positive, and negative predictive values of MMP7 immunohistochemistry were 91.3%, 93.02%, 87.5%, and 95.2% respectively. Conclusion: MMP7 immunohistochemistry may be an adjunct to histomorphology in BA.

Matrix Metalloproteinase-7 and Osteopontin Serum Levels as Biomarkers for Biliary Atresia

OBJECTIVES

Matrix metallopeptidase-7 (MMP-7) and osteopontin (OPN) are important components in the pathophysiology of fibrosis in biliary atresia (BA). There has been much recent interest in MMP-7 serum level in the diagnosis of BA. We aimed to assess the diagnostic accuracy and prognostic value of both MMP-7 and OPN in a Western BA study.

METHODS

Diagnostic value was assessed by comparison of serum MMP-7 and OPN levels in infants with BA and age-matched cholestatic controls. Prognostic value was assessed through subsequent clearance of jaundice (COJ) and need for liver transplantation (LT).

RESULTS

Serum was assessed from 32 BA and 27 controls. Median MMP-7 was higher in BA (96.4 vs 35 ng/mL; P < 0.0001) with an optimal cut-off value of 69 ng/mL. Sensitivity and specificity was 68% and 93%, respectively [negative predictive value (NPV) = 71%]. Similarly, median OPN was higher in BA (1952 vs 1457 ng/mL; P = 0.0001) and an optimal cut-off of 1611 ng/mL. Sensitivity and specificity was 84% and 78%, respectively (NPV = 81%). MMP-7 level correlated positively with Ishak liver fibrosis score (r = 0.27, P = 0.04). Neither MMP-7 (70 vs 100 ng/mL; P = 0.2) nor OPN (1969 vs 1939 ng/mL; P = 0.3) were predictive of COJ, or need for LT (99 vs 79 ng/mL; P = 0.7, and 1981 vs 1899 ng/mL; P = 0.2), respectively.

CONCLUSIONS

MMP-7 and OPN may have contributory value in the diagnosis of BA, but remain far of the "gold standard" role. Much more prospective data are required and collaborative multi-center initiatives should be the next logical steps.

A Pilot Study of Biliary Atresia Newborn Screening Using Dried Blood Spot Matrix Metalloproteinase-7

OBJECTIVES

Timely diagnosis is a critical challenge and is associated with improved survival of biliary atresia (BA) patients. We aimed to measure matrix metalloproteinase-7 (MMP-7) levels in BA patients within 3 days of birth using the dried blood spot (DBS) method and evaluate its potential as a screening tool.

METHODS

The study enrolled 132 patients, including 25 patients diagnosed with BA and 107 non-BA patients with other congenital or perinatal conditions from the National Taiwan University Children Hospital. The stored DBS samples collected from 48 to 72 hours of life were retrieved from newborn screening centers. MMP-7 on the DBS was quantified using a sensitive sandwich enzyme-linked immunosorbent assay (ELISA).

RESULTS

The MMP-7 levels of BA patients on the DBS were significantly higher than those of non-BA patients (19.2 ± 10.4 vs 5.6 ± 2.7 ng/mL, P value < 0.0001). MMP-7 levels in non-BA patients, including 5 patients with hepatobiliary structural anomaly, 9 patients with intrahepatic cholestasis, and 93 patients with other perinatal diseases, were 11.6 ± 4.2 ng/mL, 6.9 ± 3.0 ng/mL, and 5.2 ± 2.1 ng/mL, respectively. The DBS MMP-7 level showed good accuracy for identifying BA, with an area under the curve of 93.7% [95% confidence interval (CI): 87.7%-99.7%]. The MMP-7 cutoff at 8.0 ng/mL showed a sensitivity of 92.0% (95% CI: 75.0%-98.6%) and specificity of 92.5% (95% CI: 85.9%-96.1%) for detecting BA from other congenital or perinatal diseases.

CONCLUSIONS

MMP-7 DBS analysis can be used to distinguish BA from other conditions as early as 3 days of age.

COL3A1, CXCL8, VCAN, THBS2, and COL1A2 are correlated with the onset of biliary atresia

BACKGROUND

Biliary atresia (BA) is a devastating progressive fibro inflammatory disorder in infants. The exact etiology of BA is still unclear. This study aimed screen key genes potentially associated with the occurrence of BA.

METHODS

All BA data was obtained from GSE46960 dataset. The limma package in R language was used for differentially expressed gene (DEG) analyses. gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis were performed on the screened DEGs, using "clusterProfiler" package. protein-protein interaction network was built based on STRING Cytoscape software (Bethesda, Rockville, MD). The logistic regression model was constructed based on the selected DEGs.

RESULTS

There were totally 78 DEGs in BA samples compared with normal samples, which were significantly enriched in 200 biological process terms, 37 molecular function terms, 17 cellular component terms, and 18 Kyoto encyclopedia of genes and genomes pathways. Among which, the top 10 genes with the highest importance in protein-protein interaction network were selected. Subsequently, on the basis of the stepwise regression method and 5-fold cross-validation, the logistic regression model constructed based on COL3A1, CXCL8, VCAN, THBS2, and COL1A2 was finally evidenced to predict the BA sample relatively reliably.

CONCLUSIONS

In conclusion, COL3A1, CXCL8, VCAN, THBS2, and COL1A2 are potentially crucial genes in BA. The logistic regression model constructed based on them could predict the BA sample relatively reliably.

Advances in understanding of biliary atresia pathogenesis and progression - a riddle wrapped in a mystery inside an enigma

INTRODUCTION

Biliary atresia is a potentially fatal condition of the bile ducts - both intra- and extrahepatic, for which we have no cure. Though principally a cholestatic condition, much of its pathology stems from its tendency to aggressively induce liver fibrosis and ultimately cirrhosis, only partially restrained by the portoenterostomy.

AREAS COVERED

This review is based on the current literature exploring the heterogeneous nature of biliary atresia. Thus, there are various phenotypes or variants of biliary atresia, each potentially with different etiological backgrounds caused by a number of hypothetical pathological mechanisms thought to be important in the genesis of the condition. Search methodology: the review (Oct. - Nov. 2022) is based on a search of PubMed (NLM) using main keyword 'biliary atresia' with supplementary searches using 'fibrosis'; 'inflammation'; 'BASM'; 'genetics'; 'surgery'; 'experimental'; 'etiology'; 'virology'; 'cases'; and 'syndromes.'

EXPERT OPINION

Future developments will be made on matching clinical variants with a more distinct pathophysiological discrimination and those pathways linking the initial cholestatic phase of biliary atresia to the early stages of fibrosis.

Questioning Diagnostic Value of Serum Matrix Metalloproteinase 7 for Biliary Atresia

Background

Matrix metalloproteinase 7 (MMP7) has been suggested as a promising biomarker in diagnosing biliary atresia (BA). This study aimed to assess the diagnostic accuracy of serum MMP7 in BA in the Middle Eastern population.

Methods and materials

In this cross-sectional study, neonates and infants with direct hyperbilirubinemia admitted to Namazi referral hospital, Shiraz, Iran, were studied. Baseline demographic and clinical characteristics and blood samples were obtained on admission. MMP7 serum concentration was measured using an enzyme-linked immunosorbent assay (ZellBio GmbH, Ulm, Germany).

Results

44 infants with a mean age of 65.59 days were studied. Of these patients, 13 cases were diagnosed with BA, and 31 cases' cholestasis related to other etiologies. Serum MMP7 concertation was 2.13 ng/mL in the BA group and 1.85 ng/mL in the non-BA group. MMP7 was significantly higher in those presented with either dark urine or acholic stool. The predictive performance capability of the MMP7 was not significant in the discrimination of BA from the non-BA group based on receiver operating characteristic curve analysis (area under curve: 0.6, 95% confidence interval: 0.45-0.75). In the optimal cut of point 1.9, the sensitivity and specificity were 84.6% and 45.1%, respectively. Further combination of MMP7 with Gamma-glutamyl transferase (GGT), alkaline phosphatase, direct and total bilirubin, and dark urine or acholic stool was not remarkably boosted the diagnostic accuracy of the test. Interestingly, GGT at a cut-off point of 230 U/L was 84.6% sensitive and 90.3% specific for BA.

Conclusion

Our results are not consistent with previous studies on this subject. Considering more conventional and available tests like GGT besides conducting future studies with greater samples and different geographical areas is recommended.

Serum biomarkers correlated with liver stiffness assessed in a multicenter study of pediatric cholestatic liver disease

BACKGROUND AND AIMS

Detailed investigation of the biological pathways leading to hepatic fibrosis and identification of liver fibrosis biomarkers may facilitate early interventions for pediatric cholestasis.

APPROACH AND RESULTS

A targeted enzyme-linked immunosorbent assay-based panel of nine biomarkers (lysyl oxidase, tissue inhibitor matrix metalloproteinase (MMP) 1, connective tissue growth factor [CTGF], IL-8, endoglin, periostin, Mac-2-binding protein, MMP-3, and MMP-7) was examined in children with biliary atresia (BA; n = 187), alpha-1 antitrypsin deficiency (A1AT; n = 78), and Alagille syndrome (ALGS; n = 65) and correlated with liver stiffness (LSM) and biochemical measures of liver disease. Median age and LSM were 9 years and 9.5 kPa. After adjusting for covariates, there were positive correlations among LSM and endoglin ( p = 0.04) and IL-8 ( p < 0.001) and MMP-7 ( p < 0.001) in participants with BA. The best prediction model for LSM in BA using clinical and lab measurements had an R2 = 0.437; adding IL-8 and MMP-7 improved R2 to 0.523 and 0.526 (both p < 0.0001). In participants with A1AT, CTGF and LSM were negatively correlated ( p = 0.004); adding CTGF to an LSM prediction model improved R2 from 0.524 to 0.577 ( p = 0.0033). Biomarkers did not correlate with LSM in ALGS. A significant number of biomarker/lab correlations were found in participants with BA but not those with A1AT or ALGS.

CONCLUSIONS

Endoglin, IL-8, and MMP-7 significantly correlate with increased LSM in children with BA, whereas CTGF inversely correlates with LSM in participants with A1AT; these biomarkers appear to enhance prediction of LSM beyond clinical tests. Future disease-specific investigations of change in these biomarkers over time and as predictors of clinical outcomes will be important.

Fractionated Bilirubin Among 252,892 Utah Newborns With and Without Biliary Atresia: A 15-year Historical Birth Cohort Study

OBJECTIVES

To determine whether neonatal conjugated or direct bilirubin levels were elevated in infants with biliary atresia, and to estimate the number of newborns that would have positive screens in the nursery necessitating repeat testing following discharge.

STUDY DESIGN

We used administrative data from a large integrated healthcare network in Utah to identify newborns who had a fractionated bilirubin recorded during birth admission from 2005 through 2019. Elevated conjugated bilirubin was defined as greater than 0.2 mg/dL and direct bilirubin was defined as greater than 0.5 mg/dL (>97.5^th percentile for the assays). We performed simulations to estimate the anticipated number of false positive screens.

RESULTS

There were 32 cases of biliary atresia and 468,161 live births during the study period (1/14,700). 252,892 newborns had fractionated bilirubin assessed including 26 of those subsequently confirmed to have biliary atresia. Conjugated or direct bilirubin was elevated in all 26 infants with biliary atresia and an additional 3,246 (1.3%) newborns without biliary atresia. Simulated data suggest nine to 21 per 1,000 screened newborns will have an elevated conjugated or direct bilirubin using laboratory-based thresholds for a positive screen. Screening characteristics improved with higher thresholds without increasing false negative tests.

CONCLUSIONS

This study validates the previous findings that conjugated or direct bilirubin are elevated in the newborn period in patients with biliary atresia. A higher threshold for conjugated bilirubin improved screening performance. Future studies are warranted to determine the optimal screening test for biliary atresia and to assess the effectiveness and cost-effectiveness of implementing such a program.

Kasai portoenterostomy delays: Is a HIDA scan worth the wait?

BACKGROUND

Biliary Atresia (BA), an obstructive cholangiopathy, is the most common cause of end-stage liver disease and liver transplantation in children. Timely differentiation of BA from other causes of neonatal jaundice remains a challenge, yet is critical to improving outcomes.

METHODS

Clinical characteristics including demographics, age at jaundice presentation, age at hepatobiliary scintigraphy, age at surgery, severity of liver fibrosis, and native-liver survival were reviewed in infants with hyperbilirubinemia and suspected BA for this single center retrospective cohort study. We investigated the accuracy of hepatobiliary scintigraphy as well as elapsed time from jaundice presentation to diagnostic intervention.

RESULTS

BA was suspected in 234 infants. BA was identified in 17% of infants with hepatobiliary scintigraphy and 72% of infants who underwent operative exploration without hepatobiliary scintigraphy. Elapsed time from jaundice presentation to Kasai Portoenterostomy (KPE) for BA patients was 2.1x longer if hepatobiliary scintigraphy was obtained (p = 0.084). The mean age at KPE for this cohort was 66.8 days (n = 54), with a significantly higher mean age at KPE (75.2 days) for infants who were later listed or underwent liver transplantation (p = 0.038). Histologically, the lowest liver fibrosis scores were seen in infants undergoing KPE <30 days old and worsened significantly with increased age (p < 0.001).

CONCLUSION

Hepatobiliary scintigraphy compared to operative exploration for the diagnostic evaluation of infants with suspected BA introduces significant time delays to KPE but enables avoidance of surgery in some infants. The temporal pattern of worsening cholestatic liver injury from BA with each day of increased age highlights the importance of intervening as early as possible for the best prognosis.

TYPE OF STUDY

Retrospective study, Level of evidence: III.

A novel prediction tool based on shear wave elastography, gallbladder ultrasound, and serum biomarkers for the early diagnosis of biliary atresia in infants younger than 60 days old

Background

Early Kasai surgery before 60 days of life results in better clinical outcomes in patients with biliary atresia (BA). We aimed to develop and validate a prediction tool for the early diagnosis of BA in infants younger than 60 days old.

Methods

This prospective study recruited consecutive infants younger than 60 days old with conjugated hyperbilirubinemia who were evaluated with an ultrasound (US) scan, including B-mode US with color Doppler flow imaging (CDFI) features and liver two-dimensional shear wave elastography (2D SWE), from March 2017 to July 2021. The reference standard for diagnosis was intraoperative cholangiography, liver biopsy, or the resolution of jaundice. Area under the receiver operating characteristic curve (AUC) analysis, logistic regression analysis, and establishment of a nomogram were performed.

Results

A total of 174 patients (mean age, 46 days), including 87 infants with BA and 87 non-BA cholestatic infants, were included in the study. The established nomogram based on gallbladder (GB) abnormality, liver 2D SWE, and serum γ-glutamyl transferase (GGT) and alanine aminotransferase (ALT) had an AUC of 0.99 [95% confidence interval (CI): 0.94-1.00], a sensitivity of 92%, and a specificity of 100%. The nomogram in the validation cohort also had good diagnostic performance in the diagnosis of BA, with an AUC of 0.98 (95% CI: 0.95-1.00).

Conclusions

The new prediction tool had a good diagnostic performance in the early prediction of BA in infants younger than 60 days old and will facilitate timely Kasai surgery.

A novel model based on immune-related genes for differentiating biliary atresia from other cholestatic diseases

PURPOSE

Based on a public gene expression database, this study established the immune-related genetic model that distinguished BA from other cholestasis diseases (DC) for the first time. We explored the molecular mechanism of BA based on the gene model.

METHODS

The BA microarray dataset GSE46960, containing BA, other cause of intrahepatic cholestasis than biliary atresia and normal liver gene expression data, was downloaded from the Gene Expression Omnibus (GEO) database. We performed a comprehensive bioinformatics analysis to establish and validate an immune-related gene model and subsequently identified hub genes as biomarkers associated with the molecular mechanisms of BA. To assess the model's performance for separating BA from other cholestasis diseases, we used receiver operating characteristic (ROC) curves and the area under the curve (AUC) of the ROC. Independent datasets GSE69948 and GSE122340 were used for the validation process.

RESULTS

The model was built using eight immune-related genes, including EDN1, HAMP, SAA1, SPP1, ANKRD1, MMP7, TACSTD2, and UCA1. In the GSE46960 and validation group, it presented excellent results, and the prediction accuracy of BA in comparison to other cholestasis diseases was good. Functional enrichment analysis revealed significant immunological differences between BA and other cholestatic diseases. Finally, we found that the TNFα-NF-κB pathway is associated with EDN1 gene expression and may explain fibrosis progression, which may become a new therapeutic target.

CONCLUSION

In summary, we have successfully constructed an immune-related gene model that can distinguish BA from other cholestatic diseases, while identifying the hub gene. Our exploration of immune genes provides new clues for the early diagnosis, molecular mechanism, and clinical treatment of biliary atresia.

Selective enlargement of left lateral segment liver volume as a potential diagnostic predictor for biliary atresia

PURPOSE

To determine an early diagnostic indicator of biliary atresia (BA), we focused on morphological left-right differences of BA livers.

METHODS

Of 74 infants with suspected BA at our hospital in the last 12 years, 25 met the conditions for investigation: 15 infants with BA (BA group) and 10 with other pathologies (non-BA group). CT volumetry of the liver in each patient was performed using a 3D image analysis system. Patient characteristics, blood data, and proportion of the left lateral segment to the total liver volume (LLS ratio) were compared between the two groups.

RESULTS

Among the patient characteristics and liver function tests, only γ-glutamyl transpeptidase (GGT) were significantly higher in the BA group (p < 0.001). The LLS ratio was 0.321 (0.227-0.382) in the BA group and 0.243 (0.193-0.289) in the non-BA group (p = 0.01). The summary cut-off, area under the curve, sensitivity, and specificity were 0.322, 0.813, 53.3, and 100% for the LLS ratio and 94.26, 0.95, 86.7, and 100% for the GGT × LLS ratio, respectively.

CONCLUSIONS

The LLS ratio is highly specific and may be an early diagnostic predictor of BA. Moreover, this segmental LLS enlargement may be associated with the etiology of BA.

Surgical and Medical Aspects of the Initial Treatment of Biliary Atresia: Position Paper

Biliary atresia, a fibro-obliterative disease of the newborn, is usually initially treated by Kasai portoenterostomy, although there are many variations in technique and different options for post-operative adjuvant medical therapy. A questionnaire on such topics (e.g., open vs. laparoscopic; the need for liver mobilisation; use of post-operative steroids; use of post-operative anti-viral therapy, etc.) was circulated to delegates (n = 43) of an international webinar (Biliary Atresia and Related Diseases-BARD) held in June 2021. Respondents were mostly European, but included some from North America, and represented 18 different countries overall. The results of this survey are presented here, together with a commentary and review from an expert panel convened for the meeting on current trends in practice.

Beta-amyloid Deposition in Biliary Atresia Reduces Liver Regeneration by Inhibiting Energy Metabolism and Mammalian Target of Rapamycin Signaling

INTRODUCTION

Biliary atresia (BA) is a devastating obstructive bile duct disease found in newborns. This study aims to investigate the roles and involved mechanisms of beta-amyloid (Aβ) in the pathogenesis of BA.

METHODS

We examined the distribution of Aβ protein and its precursor in the livers of patients with BA. A murine liver organoid and a zebrafish model were established to investigate the exact roles of Aβ in liver regeneration for BA.

RESULTS

Both Aβ mRNA and protein significantly increased in livers of infants with BA and deposited around the central vein. In the plasma, Aβ elevated significantly in patients with BA and positively correlated with liver injury progression. In vitro , Aβ treatment induced abnormal morphology and caused impaired growth in liver organoids. Energy metabolism analysis demonstrated Aβ increased aerobic glycolysis and reduced ATP synthase in organoids, in which the mammalian target of rapamycin signaling was suppressed. In vivo , Aβ42 exposure caused liver degeneration in zebrafish larvae.

DISCUSSION

Aβ depositing in livers of infants with BA reduced the liver regeneration through attenuating mitochondrial respiration and mammalian target of rapamycin signaling.

Gamma-Glutamyl Transferase Combined With Conventional Ultrasound Features in Diagnosing Biliary Atresia: A Two-Center Retrospective Analysis

OBJECTIVES

To develop and validate a biliary atresia (BA) diagnostic score based on serum gamma-glutamyl transferase (GGT) levels and conventional ultrasound features for discriminating BA in patients with jaundice from two centers.

METHODS

A total of 958 patients from one hospital were classified as the derivation cohort, and 725 patients from another hospital were classified as the validation cohort. The optimal GGT cutoff value for diagnosing BA was calculated in the derivation cohort and subsequently verified in the validation cohort. Gallbladder abnormalities and the triangular cord (TC) sign were evaluated in all patients. A BA diagnostic score was developed for diagnosing BA using the GGT levels, gallbladder abnormalities and the TC sign based on the data from the derivation cohort followed by external validation.

RESULTS

Based on the optimal cutoff value 350.0 U/L, GGT yielded a sensitivity of 59.3% and specificity of 85.4% in diagnosing BA. The area under the receiver operating characteristic curve (AUC 0.724) was inferior to that of the gallbladder (AUC 0.911, P < .001) and comparable to that of the TC sign (AUC 0.771, P = .128). The combination of GGT and ultrasound diagnosis could help to reduce the misdiagnosis of 9 infants with BA. The BA diagnostic score yielded a sensitivity of 93.3% and specificity of 95.0% with the highest AUC in this study (0.941).

CONCLUSIONS

GGT can add diagnostic value to ultrasound examination when diagnosing BA. The BA diagnostic score based on GGT, gallbladder abnormalities and the TC sign shows satisfactory discrimination abilities in BA.

Diagnostic values of plasma matrix metalloproteinase-7, interleukin-8, and gamma-glutamyl transferase in biliary atresia

Biliary atresia (BA) is a severe cholestatic liver disease in children featuring cholestasis and liver fibrosis. The early diagnosis of BA is still challenging. This study aimed to evaluate the diagnostic values of matrix metalloprotease-7 (MMP-7), interleukin-8 (IL-8), and gamma-glutamyl transferase (GGT) in BA. Infants diagnosed with BA and non-BA between 2013 and 2018 were retrospectively analyzed. Plasma levels of MMP-7, IL-8, and GGT were measured in these infants. The receiver operating characteristic (ROC) curves and area under the ROC curve (AUC) were used to assess the diagnostic values of MMP-7, IL-8, and GGT. The expression of MMP-7 and IL-8 in the livers was detected by immunofluorescence staining. A total of 229 infants were enrolled in this study: 156 BA infants and 73 non-BA infants including 16 ones with infantile hepatitis syndrome. The plasma levels of MMP-7, IL-8, and GGT in BA infants had a median of 11.8 ng/mL (interquartile range, IQR: 5.3-57.5), 1.5 ng/mL (IQR: 1.0-2.8), and 381.0 U/L (IQR: 197.0-749.0), respectively, which were higher than non-BA subjects [MMP-7, 4.4 ng/mL (IQR: 3.3-6.1); IL-8, 0.7 ng/mL (IQR: 0.5-1.0); GGT, 59.0 U/L (IQR: 26.0-124.0)]. The AUC values of MMP-7, IL-8, and GGT for the diagnosis of BA were 0.8035, 0.8083, and 0.9126, respectively. The AUC values of MMP-7 + IL-8, MMP-7 + GGT, IL-8 + GGT, and MMP-7 + IL-8 + GGT for the diagnosis of BA were 0.8248, 0.9382, 0.9168, and 0.9392, respectively. The AUC values of MMP-7, IL-8, and GGT for differentiating BA infants with cholic stool from non-BA infants with cholic stool were 0.8006, 0.8258, and 0.9141, respectively. The expression of MMP-7 and IL-8 was increased in the cholangiocytes in BA livers.   Conclusion: Plasma MMP-7, IL-8, and GGT alone or a combination of them has good accuracy to differentiate BA from non-BA and may be reliable biomarkers for BA. What is Known: • Biliary atresia (BA) is a severe cholestatic liver disease in children featuring cholestasis and progressive liver fibrosis. • Although early diagnosis of BA is crucial for good outcomes, it remains a clinical challenge. What is New: • Plasma MMP-7, IL-8, and GGT alone or a combination of them has good accuracy to differentiate BA from non-BA. • Plasma MMP-7, IL-8, and GGT have good accuracy for differentiating BA infants with cholic stool from non-BA infants with cholic stool.

Protocols of Investigation of Neonatal Cholestasis-A Critical Appraisal

Neonatal cholestasis (NC) starts during the first three months of life and comprises extrahepatic and intrahepatic groups of diseases, some of which have high morbimortality rates if not timely identified and treated. Prolonged jaundice, clay-colored or acholic stools, and choluria in an infant indicate the urgent need to investigate the presence of NC, and thenceforth the differential diagnosis of extra- and intrahepatic causes of NC. The differential diagnosis of NC is a laborious process demanding the accurate exclusion of a wide range of diseases, through the skillful use and interpretation of several diagnostic tests. A wise integration of clinical-laboratory, histopathological, molecular, and genetic evaluations is imperative, employing extensive knowledge about each evaluated disease as well as the pitfalls of each diagnostic test. Here, we review the difficulties involved in correctly diagnosing the cause of cholestasis in an affected infant.

Comparing Serum Matrix Metalloproteinase-7 in Parenteral Nutrition-Associated Liver Disease and Biliary Atresia

In this cross-sectional study, serum matrix metalloproteinase-7 levels were significantly lower in infants with jaundice and parenteral nutrition-associated liver disease compared with those with confirmed biliary atresia. Serum metalloproteinase-7 may aid in excluding biliary atresia and thus may minimize invasive testing in infants with a history of parenteral nutrition.

The cholestatic infant: updates on diagnosis and genetics

PURPOSE OF REVIEW

Cholestasis in infants can indicate a serious hepatobiliary disease and requires timely assessment, diagnosis and intervention to prevent progression to serious liver decompensation. This report aims to highlight recently published studies regarding diagnosis and treatment of cholestasis in infants.

RECENT FINDINGS

The evaluation of neonatal cholestasis can be challenging, requiring the assessment of a broad differential diagnosis in timely fashion. The Italian Society of pediatric gastroenterology, hepatology, and nutrition position paper on the evaluation of neonatal cholestasis is reviewed and compared to other published guidelines. In biliary atresia, the most time-sensitive of these diagnoses, serum matrix metalloproteinase-7 was studied in Japanese infants with biliary atresia with excellent diagnostic performance characteristics. Genetic testing panels are an increasingly used tool to help identify causes of cholestasis. An American experience of genetic testing in large cohort of infants identified a definite or possible genetic diagnosis in 11% of cholestatic infants. In the treatment of prutitus in Alagille syndrome and progressive familial intrahepatic cholestasis the clinical studies of two newly Food and Drug Administration approved ileal bile acid transport inhibitors are discussed. New information on the prevalence of cytomegalovirus and idiopathic cholestasis as other etiologies of infant cholestasis is also reviewed. Lastly, new insight on potential maternal microbiome regulation on biliary disease in neonates on experimental biliary atresia models is discussed.

SUMMARY

Cholestasis in infants requires timely diagnosis and intervention. There are exciting new diagnostic and treatment options now being studied which could help minimize the likelihood of advanced liver disease and development of serious complications.

Dynamic analysis of serum MMP-7 and its relationship with disease progression in biliary atresia: a multicenter prospective study

PURPOSE

We aimed to assess the dynamic changing trend of serum matrix metalloproteinase-7 (MMP-7) in biliary atresia (BA) patients from diagnosis to LTx to further elucidate its clinical value in diagnosis and prognoses and its relationship with disease progression.

METHODS

In this multicentre prospective study, 440 cholestasis patients (direct bilirubin level of > 17 μmol/L) were enrolled. Serum MMP-7 levels were measured using an enzyme-linked immunosorbent assay at diagnosis, 1 week, 2 weeks, 1 month, 6 weeks, 2 months, 3 months, 6 months and then every 6 months post-KPE. The medical record at each follow-up visit for post-Kasai portoenterostomy patient was collected and analyzed.

RESULTS

Using a cut-off value of > 26.73 ng/mL, serum MMP-7 had an AUC of 0.954 in BA neonates and 0.983 in BA infants. A genetic mutation (G137D) was associated with low MMP-7 levels in serum of BA patients. MMP-7 showed a mediation effect on the association between inflammation and liver fibrosis in BA patients. Four dynamic patterns of serum MMP-7 post-KPE were associated with prognosis. Serum MMP-7 was the only significant predictor at 6 weeks post-KPE and the most accurate predictor at 3 months post-KPE of survival with the native liver in 2 years.

CONCLUSION

As one of the critical factors associated with BA occurrence and progression, serum MMP-7 can be used for early diagnosis of BA and post-KPE MMP-7 level is the earliest prognostic biomarker so far.

The Bioinformatic Study Uncovers Probable Critical Genes Involved in the Pathophysiology of Biliary Atresia

Background

Biliary atresia (BA) is an uncommon illness that causes the bile ducts outside and within the liver to become clogged in babies. If left untreated, the cholestasis causes increasing conjugated hyperbilirubinemia, cirrhosis, and hepatic failure. BA has a complicated aetiology, and the mechanisms that drive its development are unknown. The objective of this study was to show the role of probable critical genes involved in the pathophysiology of biliary atresia.

Methods

We utilised the public Gene Expression Omnibus (GEO) microarray expression profiling dataset GSE46960 to find differentially expressed genes (DEGs) in 64 biliary atresia newborns, 14 infants with various causes of intrahepatic cholestasis, and 7 deceased-donor children as control subjects in our study. The relevant information was looked into. The important modules were identified after functional enrichment, GO and KEGG pathway analyses, protein-protein interaction (PPI) network analyses, and GSEA analysis.

Results

The differential expression analysis revealed a total of 22 elevated genes. To further understand the biological activities of the DEGs, we run functional enrichment analyses on them. Meanwhile, KEGG analysis has revealed significant enrichment of pathways involved in activating cross-talking with inflammation and fibrosis in BA. SERPINE1, THBS1, CCL2, MMP7, CXCL8, EPCAM, VCAN, ITGA2, AREG, and HAS2, which may play a significant regulatory role in the pathogenesis of BA, were identified by PPI studies.

Conclusion

Our findings suggested 10 hub genes and probable mechanisms of BA in the current study through bioinformatic analysis.

Serum matrix metalloproteinase-7 levels in infants with cholestasis and biliary atresia

Background

The aim of this study was to evaluate the serum level of matrix metalloproteinase 7 (MMP7) in infants with cholestasis and the diagnostic values of this biomarker to differentiate biliary atresia (BA) from other causes of cholestasis.

Methods

This multi-center study is conducted during 2 years in Mofid children’s hospital and Children’s Medical Center, Pediatrics Center of Excellence Tehran, Iran. 54 infants with cholestasis were enrolled in this study with a control group consists of 41 healthy infants with the same age. Serum samples were taken from all these patients to assess serum levels of MMP7, Gamma-glutamyl Transferase (GGT). For each biomarker, we calculated the sensitivity and specificity and other statistical characteristics.

Results

There were 89 subjects, 22 patients with BA, 32 patients with non-BA cholestasis and 41 subjects as control group. The mean serum MMP7 levels in BA, non-BA cholestasis and control group was 15.91 ng/ml ± 6.64, 4.73 ng/ml ± 2.59 and 0.49 ng/ml ± 0.33, respectively. The best cut-off point is calculated 7.8 ng/ml for MMP7 and 434.5 U/L for GGT. The area under curve (AUC) for these two markers are 0.988 ± 0.008 and 0.854 ± 0.052, respectively. The sensitivity and specificity of MMP7 to differentiate biliary atresia from nonbiliary atresia cholestasis in our study was 95.5% and 94.5%, respectively. The sensitivity and specificity of GGT was 77.3% and 77.8%, respectively. These results show that the MMP7 has more sensitivity and specificity in differentiation.

Conclusion

MMP7 demonstrated good accuracy to differentiate biliary atresia from other causes of cholestasis.

Identification of Hub Genes and Immune Infiltration in Pediatric Biliary Atresia by Comprehensive Bioinformatics Analysis

Background: Biliary atresia (BA) is the leading cause of pediatric liver failure and pediatric liver transplantation worldwide. Evidence suggests that the immune system plays a central role in the pathogenesis of BA. Methods: In this work, the novel immune-related genes between BA and normal samples were investigated based on weighted gene co-expression network analysis (WGCNA) and the deconvolution algorithm of CIBERSORT. Results: Specifically, 650 DEGs were identified between the BA and normal groups. The blue module was the most positively correlated with BA containing 3274 genes. Totally, 610 overlapping BA-related genes of DEGs and WGCNA were further used to identify IRGs. Three IRGs including VCAM1, HLA-DRA, and CD74 were finally identified as the candidate biomarkers. Particularly, the CD74 biomarker was discovered for the first as a potential immune biomarker for BA. Conclusions: Possibly, these 3 IRGs might serve as candidate biomarkers and guide the individualized treatment strategies for BA patients. Our results would provide great insights for a deeper understanding of both the occurrence and the treatment of BA.

Serum matrix metalloproteinase-7 in biliary atresia: A Japanese multicenter study

BACKGROUND

Biliary atresia (BA) is among the commonest indications for liver transplantation (LT) in children. We examined whether serum matrix metalloproteinase-7 (MMP-7) is useful for diagnosis of BA in Japanese infants, and whether serum MMP-7 concentrations before and after Kasai portoenterostomy (KP) predicted LT within a year.

METHODS

Subjects under 6 months old at eight pediatric centers in Japan were enrolled retrospectively, including patients with cholestasis and normal controls (NC) without liver disease. Patients with cholestasis were divided into groups representing BA versus cholestasis from other causes (non-BA). Serum samples were collected from patients with BA at diagnosis and 1 and 4 weeks after KP, as well as from non-BA and NC.

RESULTS

Serum MMP-7 concentrations were significantly higher in BA at diagnosis (median, 89.1 ng/ml) than in non-BA (11.0; p < 0.001) or NC (10.3; p < 0.001). Receiver operating characteristic (ROC) analysis of MMP-7 for BA versus non-BA yielded an area under the ROC curve of 0.99 (95% confidence interval, 0.96-1.00). An optimal cut-off value of 18.6 ng/ml for serum MMP-7 in diagnosing BA demonstrated sensitivity and specificity of 100% and 90%, respectively. Serum MMP-7 before and 1 week and 4 weeks after KP did not differ significantly between BA requiring only KP and BA requiring LT after KP.

CONCLUSION

Serum MMP-7 is a useful marker for diagnosis of BA in Japanese infants, but it could not predict LT within a year.

Percutaneous ultrasound-guided cholecystocholangiography with microbubbles combined with liver biopsy for the assessment of suspected biliary atresia

BACKGROUND

Percutaneous ultrasound (US)-guided cholecystocholangiography is effective in diagnosing biliary atresia for infants with a gallbladder >1.5 cm in length on US. However, whether it is still effective for other types of gallbladders needs further clarification.

OBJECTIVE

To evaluate the diagnostic performance and safety of percutaneous US-guided cholecystocholangiography combined with liver biopsy in children with suspected biliary atresia and with different types of gallbladders on US.

MATERIALS AND METHODS

Sixty-five infants were referred for percutaneous US-guided cholecystocholangiography with microbubbles and liver biopsy after an equivocal (n=39) or highly suspected (n=26) US diagnosis of biliary atresia. Two radiologists evaluated US and percutaneous US-guided cholecystocholangiography images in consensus. One pathologist independently evaluated liver specimens. We used the unpaired t-test, Mann-Whitney U test and chi-square test to analyze the data.

RESULTS

Of the 65 infants, 59 (90.8%) underwent a successful percutaneous US-guided cholecystocholangiography, with both sensitivity and specificity of 100%. All six infants for whom puncture failed had contracted gallbladders. The sensitivity and specificity of liver biopsy in the diagnosis of biliary atresia were 89.7% (26/29) and 83.3% (30/36), respectively. When percutaneous US-guided cholecystocholangiography and liver biopsy were combined, all infants gained correct diagnosis, and in 35 infants (97.2%, 35/36) biliary atresia could be excluded without intraoperative cholangiography. Twenty-two of 65 infants (33.8%) had fluid collections around the liver related to puncture. None of these complications needed treatment.

CONCLUSION

Percutaneous US-guided cholecystocholangiography combined with liver biopsy appears safe and effective for excluding or confirming biliary atresia in cholestatic infants with a dilated gallbladder on US.

Current Understanding in the Clinical Characteristics and Molecular Mechanisms in Different Subtypes of Biliary Atresia

Biliary atresia is a severe obliterative cholangiopathy in early infancy that is by far the most common cause of surgical jaundice and the most common indicator for liver transplantation in children. With the advanced knowledge gained from different clinical trials and the development of research models, a more precise clinical classification of BA (i.e., isolated BA (IBA), cystic BA (CBA), syndromic BA (SBA), and cytomegalovirus-associated BA (CMVBA)) is proposed. Different BA subtypes have similar yet distinguishable clinical manifestations. The clinical and etiological heterogeneity leads to dramatically different prognoses; hence, treatment needs to be specific. In this study, we reviewed the clinical characteristics of different BA subtypes and revealed the molecular mechanisms of their developmental contributors. We aimed to highlight the differences among these various subtypes of BA which ultimately contribute to the development of a specific management protocol for each subtype.

Neonatal diagnosis of biliary atresia: a practical review and update

Biliary atresia is challenging to diagnose because many of the clinical and imaging features of this condition overlap with those of other causes of cholestasis in newborns. When jaundice persists beyond 2 weeks of age, the neonate should be evaluated for cholestasis, and biliary atresia - the most common cause of neonatal cholestasis - should be considered. It is critical to diagnose biliary atresia early because failure to treat can result in hepatic fibrosis and death in less than 1 year. In this paper, we review the current diagnostic imaging methods, differential considerations and treatment options for biliary atresia.

The Liver Biopsy in Neonatal Cholestasis: Just a Cherry on Top?

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Diagnostic Tools for Early Detection of Biliary Atresia: Is a Newborn Screen Attainable?

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TGF-β1-Mediated Leukocyte Cell-Derived Chemotaxin 2 Is Associated With Liver Fibrosis in Biliary Atresia

OBJECTIVE

Biliary atresia (BA) presents as a severe infantile cholangiopathy disease, characterized by progressive liver fibrosis and the resulting poor prognosis. Leukocyte cell-derived chemotaxin 2 (LECT2) was proposed as the key gene associated with hepatic fibrosis in BA, but the molecular mechanism is unclear. This study aims to investigate the function of LECT2 in BA.

METHODS

A total of 53 patients were enrolled in this study; 36 patients with BA, and 17 control patients with cholestasis, including congenital biliary dilations, biliary hypoplasia, and inspissated bile syndrome. The role of LECT2 in BA was analyzed using histological and cytological tests. The correlation between LECT2 and infiltrating immune cells was further analyzed by bioinformatics. The analyses were conducted using correlational analyses and ROC curves.

RESULTS

LECT2 was highly expressed in infants with BA and positively related with fibrosis (0.1644 ± 0.0608 vs. 0.0779 ± 0.0053, p < 0.0001; r _s = 0.85, p < 0.0001). Serum levels of LECT2 showed high distinguishing features for patients with BA having an AUC of 0.95 (95% CI: 0.90-1.00). CD163 was highly expressed in the aggravation of fibrosis (0.158 ± 0.062 vs. 0.29 ± 0.078, p < 0.0001), and the expression of LECT2 was positively correlated with the accumulation of CD163⁺ macrophages (r = 0.48, p = 0.003). The bioinformatic analysis also showed that LECT2 was positively correlated with macrophage M2 (r = 0.34, p = 0.03). TGF-β1 and CD163 colocalized to the portal area in the livers of patients with BA. Moreover, TGF-β1 upregulated the expression of LECT2.

CONCLUSION

LECT2 is highly expressed in both BA liver tissue and serum, and serum LECT2 is a potential diagnostic biomarker of BA. Meanwhile, TGF-β1 is secreted by macrophages to regulate LECT2 associated with BA liver fibrosis.

Plasma amyloid-beta levels correlated with impaired hepatic functions: An adjuvant biomarker for the diagnosis of biliary atresia

BACKGROUND

Biliary atresia (BA) is an infantile fibro-obstructive cholestatic disease with poor prognosis. An early diagnosis and timely Kasai portoenterostomy (KPE) improve clinical outcomes. Aggregation of amyloid-beta (Aβ) around hepatic bile ducts has been discovered as a factor for BA pathogenesis, yet whether plasma Aβ levels correlate with hepatic dysfunctions and could be a biomarker for BA remains unknown.

METHOD

Plasma samples of 11 BA and 24 controls were collected for liver function test, Aβ40 and Aβ42 measurement by enzyme-linked immunosorbent assay (ELISA). Pearson's chi-squared test or Mann-Whitney U test was performed to assess differences between groups. Correlation between Aβ42/Aβ40 and liver function parameters was performed using Pearson analysis. The area under the receiver-operative characteristic (ROC) curve (area under curve; AUC) was measured to evaluate the diagnostic power of Aβ42/Aβ40 for BA. Diagnostic enhancement was further evaluated by binary regression ROC analysis of Aβ42/Aβ40 combined with other hepatic function parameters.

RESULTS

Plasma Aβ42/Aβ40 was elevated in BA patients. Aβ42 displayed a weak positive correlation with γ-glutamyl transpeptidase (GGT) (Pearson's correlation = 0.349), while there was no correlation for Aβ40 with hepatic functions. Aβ42/Aβ40 was moderately correlated with GGT, total bile acid (TBA), direct bilirubin (DBIL) (Pearson's correlation = 0.533, 0.475, 0.480), and weakly correlated with total bilirubin (TBIL) (Pearson's correlation = 0.337). Aβ42/Aβ40 showed an acceptable predictive power for cholestasis [AUC = 0.746 (95% CI: 0.552-0.941), p < 0.05]. Diagnostic powers of Aβ42/Aβ40 together with hepatic function parameters for cholestasis were markedly improved compared to any indicator alone. Neither Aβ42/Aβ40 nor hepatic function parameters displayed sufficient power in discriminating BA from choledochal cysts (CC); however, combinations of Aβ42/Aβ40 + GGT along with any other hepatic function parameters could differentiate BA from CC-cholestasis (AUC = 1.000, p < 0.05) with a cut-off value as 0.02371, -0.28387, -0.34583, 0.06224, 0.01040, 0.06808, and 0.05898, respectively.

CONCLUSION

Aβ42/Aβ40 is a good indicator for cholestasis, but alone is insufficient for a distinction of BA from non-BA. However, Aβ42/Aβ40 combined with GGT and one other hepatic function parameter displayed a high predictive power as a screening test for jaundiced neonates who are more likely to be BA, enabling them to early intraoperative cholangiography for BA confirmation and KPE to improve surgical outcomes. However, a multi-centers validation is needed before introduction into daily clinical practice.

Serum Matrix Metalloproteinase 7 as a Diagnostic and Prognostic Biomarker for Extrahepatic Biliary Atresia

Background

Differentiation of neonatal cholestasis into neonatal hepatitis (NH) and extrahepatic biliary atresia (EHBA) is essential to formulate the treatment plan; promptness is indispensable for optimal outcomes. The clinical and nonoperative algorithms lack precision; the gold standard investigations (liver biopsy or per-operative cholangiogram) are invasive. There is a need for a noninvasive test which is both, sensitive and specific and has a high likelihood ratio.

Aim

To study the (diagnostic) role of matrix metalloproteinase 7 (MMP-7) as a serum biomarker to differentiate between EHBA and NH and evaluate the prognostic significance in EHBA based on its correlation with liver histopathology and serological predictors of liver fibrosis - Aspartate-to-Platelet Ratio Index (APRI) and Fibrosis-4 (FIB-4).

Materials and Methods

This was a prospective study conducted upon patients of neonatal cholestasis presenting with acholic stools (n = 46) with equal number of controls (n = 45) with no liver pathology. Observational parametric included disease-specific workup and serum MMP-7 levels (all participants); liver biopsyl and APRI-FIB-4 (EHBA).

Results

(Diagnostic) Serum MMP-7 levels were significantly elevated in EHBA (n = 25; 28 ng/mL) as compared to those in NH (n = 21; 1.88 ng/mL) and normal infants (n = 45; 1.2 ng/mL) (P < 0.001 for both). Serum cutoff at 4.99 ng/mL differentiated EHBA-NH with a high sensitivity (96%), specificity (90.5%), and a negative predictive value (95%), with the number needed to misdiagnose being 23. (Prognostic) Inflammatory activity and fibrosis-stage on liver histopathology (METAVIR-and-Ishak scores) correlated with MMP-7 levels. APRI and FIB-4 scores also depicted a strong correlation with each other, age of the patient, and liver fibrosis.

Conclusions

MMP-7 has a diagnostic value in differentiating EHBA from NH and may also be used as a prognostic biomarker in the follow-up of these patients. MMP-7 levels in controls may be used as a baseline for future studies.