Utility of Transient Elastography in Differentiating Biliary Atresia from Other Causes of Neonatal Cholestasis: A Prospective Observational Study

Background

Differentiating biliary atresia (BA) from non-BA is paramount, as their management and outcome differ. So far, BA is diagnosed by intraoperative cholangiogram (IOC) or liver biopsy. However, literature is sparse on the utility of transient elastography (TE) in neonatal cholestasis. We aimed to study the usefulness and accuracy of TE in differentiating BA from other causes of neonatal cholestasis (NCS).

Methods

A prospective observational study was conducted from June 2021 to February 2024; consecutive cases of NCS were recruited. Patients were grouped as BA and non-BA. All patients underwent clinical, laboratory, and radiological evaluation, along with TE. Receiver operating characteristic curve (ROC) analysis was performed to derive an LSM cutoff for diagnosing BA. The liver stiffness measurement (LSM) was correlated with histopathological fibrosis.

Results

We enrolled 135 patients, BA (n = 68) and non-BA (n = 67). The median LSM was higher in BA, 19.4 (12.9-38.75) kPa vs. 12.0 (8.4-17.9) kPa (P=<0.001). LSM positively correlated with the METAVIR fibrosis score (Spearman's correlation coefficient, r = 0.590, P < 0.001). We derived an LSM cutoff of 13.1 kPa to differentiate BA from non-BA (sensitivity 75%, specificity 61.2%, AUC 0.736). By adding ultrasound (USG) finding of a small gallbladder (<19 mm) to our LSM cutoff (13.1 kPa), the sensitivity improved to 97.0%, but specificity remained low (52.2%).

Conclusion

LSM correlates well with histopathological fibrosis in NCS. An LSM cut off of 13.1 kPa can be used to differentiate BA from non-BA with a sensitivity of 75%. In resource-constraint setting where liver biopsy and IOC may not be available, TE in combination with USG can be a good screening tool for BA (sensitivity 97%).

Portal vein hypoplasia is present in patients with biliary atresia at the time of diagnosis

BACKGROUND

In patients with biliary atresia (BA), severe portal hypertension (HTN) develops even with successful bile flow restoration, suggesting an intrinsic factor driving portal HTN independent from bile obstruction. We hypothesize that patients with BA have abnormal portal vein (PV) development, leading to PV hypoplasia.

METHODS

In this observational cohort study, we enrolled patients who were referred to a tertiary center from 2017 to 2021 to rule out BA. Newborns who underwent computed tomography angiogram as a clinical routine before intraoperative cholangiogram, and laparoscopic Kasai hepatoportoenterostomy. The diameter of the PV and hepatic artery (HA) were compared to the degree of liver fibrosis in the wedge biopsies. The jaundice clearance, native liver survival, and clinical portal hypertensive events, including ascites development and intestinal bleeding, were assessed.

RESULTS

47 newborns with cholestasis were included in the cohort; 35 were diagnosed with BA. The patients with BA had a smaller median PV diameter (4.3 vs. 5.1 mm; p < 0.001) and larger median HA diameter (1.4 vs. 1.2 mm; p < 0.05) compared to the patients with other forms of cholestasis. The median PV and HA diameter did not correlate with the degree of liver fibrosis. Among 35 patients with BA, 29 patients (82.9%) achieved jaundice clearance, and 23 patients (65.7%) were alive with their native liver at two years of age. Seven patients (20%) developed intestinal bleeding, and seven patients (20%) developed ascites, with one overlapping patient.

CONCLUSION

PV hypoplasia is present in patients with BA independent of liver fibrosis at the time of diagnosis.

Novel Scoring Systems and Age-Based Hepatic Shear Wave Stiffness Cut-Offs for Improving Sonographic Diagnosis of Biliary Atresia

OBJECTIVES

To make sonographic evaluation for biliary atresia (BA) more objective and reproducible using scoring systems, and evaluate hepatic shear wave elastography (SWE) as an adjunct in sonographic diagnosis of BA.

METHODS

Sixty-four infants with cholestatic jaundice were enrolled between June 2016 and March 2018 in this prospective observational cohort study. Sonography and SWE was performed with SuperSonic Aixplorer system. Novel scoring systems were developed incorporating established sonographic parameters and hepatic stiffness values and analysed using SPSS software.

RESULTS

Of the 18 patients confirmed as BA, 3 were misdiagnosed on conventional sonography (16.7%) as non-BA. Gall bladder (GB) wall irregularity and fasting GB length were the most accurate (93.8%) and most specific (97.8%) individual parameters, respectively. A significant difference was noted in the triangular cord (TC) thickness of BA and non-BA infants (p <0.001), with a high specificity of 95.6% for a 4 mm cut-off value for a positive TC sign. Comparison of hepatic SWE stiffness among age-matched groups of BA and non-BA showed significant differences (≤60 d: p = 0.003; >60 d: p <0.001) but with a reduced accuracy (93.8%). Diagnostic accuracy of greyscale scoring system (96.9%), greyscale + elastography scoring system in ≤60 d (94.4%) and >60 d (97.8%) were better than that of conventional sonographic diagnosis (93.8%).

CONCLUSIONS

Grey scale scoring system improves the accuracy of sonographic diagnosis of BA without any additional cost or time penalty along with making it universally reproducible. SWE has only an adjunctive role, if any, in the sonographic diagnosis of BA.

Porta hepatis lymph nodes on US: not only identify biliary atresia but also predict outcomes after Kasai portoenterostomy surgery

OBJECTIVES

To evaluate the usefulness of porta hepatis lymph nodes (PHLNs) on ultrasonography (US) scans in diagnosing biliary atresia (BA) and predicting the outcomes after Kasai portoenterostomy (KPE) surgery.

METHODS

A total of 668 patients from one hospital were enrolled in the study (542 non-BA and 126 BA). The independent and combined diagnostic efficacy of PHLNs, triangular cord (TC) thickness, and gallbladder morphology were assessed by drawing the receiver operating characteristic (ROC) curves and counting the area under the ROC curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The US features, histopathological findings of PHLNs, and serum total bilirubin (TBIL) levels 3 months post-KPE were correlated.

RESULTS

The AUC, sensitivity, specificity, PPV, and NPV of PHLNs with hyperechogenicity and a maximum length larger than 8.4 mm were 0.898, 81.8%, 97.8%, 89.6%, and 95.8%, respectively. The combination of PHLNs, TC thickness, and gallbladder morphology achieved the best overall diagnostic efficacy among all indicators with an AUC of 0.927 and a sensitivity of 99.2%. The germinal center number and bile particle number of PHLNs were positively correlated with pathological size and US echogenicity intensity of PHLNs, respectively (r = 0.591, 0.377, p = 0.001, 0.004). The pathological size of PHLNs in BA patients was negatively correlated with jaundice clearance status 3 months after KPE surgery (r = -0.385, p = 0.047).

CONCLUSION

PHLNs with hyperechogenicity and a maximum length > 8.4 mm are useful US indicators for BA diagnosis. Additionally, the enlargement of PHLNs might play a role in predicting outcomes of KPE surgery.

CRITICAL RELEVANCE STATEMENT

The article proposed for the first time that PHLNs with hyperechogenicity and a maximum length > 8.4 mm are a useful US indicator for diagnosing BA.

KEY POINTS

PHLNs may be helpful in diagnosing BA and predicting outcomes after surgery. Enlarged hyperechoic PHLNs are a useful diagnostic indicator for BA, and play a role in predicting surgical outcomes. These findings can assist clinicians in more accurately diagnosing BA, enabling more timely treatments.

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.

Interpretable artificial intelligence-based app assists inexperienced radiologists in diagnosing biliary atresia from sonographic gallbladder images

BACKGROUND

A previously trained deep learning-based smartphone app provides an artificial intelligence solution to help diagnose biliary atresia from sonographic gallbladder images, but it might be impractical to launch it in real clinical settings. This study aimed to redevelop a new model using original sonographic images and their derived smartphone photos and then test the new model's performance in assisting radiologists with different experiences to detect biliary atresia in real-world mimic settings.

METHODS

A new model was first trained retrospectively using 3659 original sonographic gallbladder images and their derived 51,226 smartphone photos and tested on 11,410 external validation smartphone photos. Afterward, the new model was tested in 333 prospectively collected sonographic gallbladder videos from 207 infants by 14 inexperienced radiologists (9 juniors and 5 seniors) and 4 experienced pediatric radiologists in real-world mimic settings. Diagnostic performance was expressed as the area under the receiver operating characteristic curve (AUC).

RESULTS

The new model outperformed the previously published model in diagnosing BA on the external validation set (AUC 0.924 vs 0.908, P = 0.004) with higher consistency (kappa value 0.708 vs 0.609). When tested in real-world mimic settings using 333 sonographic gallbladder videos, the new model performed comparable to experienced pediatric radiologists (average AUC 0.860 vs 0.876) and outperformed junior radiologists (average AUC 0.838 vs 0.773) and senior radiologists (average AUC 0.829 vs 0.749). Furthermore, the new model could aid both junior and senior radiologists to improve their diagnostic performances, with the average AUC increasing from 0.773 to 0.835 for junior radiologists and from 0.749 to 0.805 for senior radiologists.

CONCLUSIONS

The interpretable app-based model showed robust and satisfactory performance in diagnosing biliary atresia, and it could aid radiologists with limited experiences to improve their diagnostic performances in real-world mimic settings.

Shear Wave Elastography: A Reliable Secondary Parameter for Diagnosing Biliary Atresia in Infants With Neonatal Cholestasis

Objective In this study, we aimed to optimize various grayscale, Doppler, and elastography parameters and evaluate their diagnostic performance in the preoperative diagnosis of biliary atresia (BA). Materials and methods A total of 158 infants aged <6 months with neonatal cholestasis (NC) were enrolled in the study and sonography was performed after four hours of fasting. For comparison of elastography, 31 exclusively age-matched controls, not suffering from liver disease, were included separately. Triangular cord and gallbladder (GB) parameters were considered as primary parameters, while right hepatic artery (RHA) caliber, RHA-to-right portal vein (RPV) ratio, hepatic subcapsular flow (HSF), and shear wave elastography (SWE) were considered as secondary parameters. Diagnosis of infants with BA was confirmed on histopathology. Data were presented as mean ±standard deviation (SD) and frequency. Differences between groups were compared using the Chi-square test and the unpaired student t-test. Receiver operating characteristic (ROC) curve analysis was done for individual ultrasound/Doppler/SWE parameters to calculate the optimal cutoff value. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for each parameter and their combinations. Results Of the primary parameters, GB contractility index (CI) and length showed the highest sensitivity and specificity respectively. A cutoff of 14 kPA was derived for SWE for the diagnosis of BA. Among secondary parameters, SWE had the best diagnostic performance, better than even the individual primary parameters. A combination of primary parameters with SWE in series showed the highest accuracy. Conclusion Among secondary parameters, elastography can prove to be highly useful. The highest accuracy in diagnosing BA can be obtained by combining primary parameters with SWE.

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.

The application of artificial intelligence to support biliary atresia screening by ultrasound images: A study based on deep learning models

Purpose

Early confirmation or ruling out biliary atresia (BA) is essential for infants with delayed onset of jaundice. In the current practice, percutaneous liver biopsy and intraoperative cholangiography (IOC) remain the golden standards for diagnosis. In Taiwan, the diagnostic methods are invasive and can only be performed in selective medical centers. However, referrals from primary physicians and local pediatricians are often delayed because of lacking clinical suspicions. Ultrasounds (US) are common screening tools in local hospitals and clinics, but the pediatric hepatobiliary US particularly requires well-trained imaging personnel. The meaningful comprehension of US is highly dependent on individual experience. For screening BA through human observation on US images, the reported sensitivity and specificity were achieved by pediatric radiologists, pediatric hepatobiliary experts, or pediatric surgeons. Therefore, this research developed a tool based on deep learning models for screening BA to assist pediatric US image reading by general physicians and pediatricians.

Methods

De-identified hepatobiliary US images of 180 patients from Taichung Veterans General Hospital were retrospectively collected under the approval of the Institutional Review Board. Herein, the top network models of ImageNet Large Scale Visual Recognition Competition and other network models commonly used for US image recognition were included for further study to classify US images as BA or non-BA. The performance of different network models was expressed by the confusion matrix and receiver operating characteristic curve. There were two methods proposed to solve disagreement by US image classification of a single patient. The first and second methods were the positive-dominance law and threshold law. During the study, the US images of three successive patients suspected to have BA were classified by the trained models.

Results

Among all included patients contributing US images, 41 patients were diagnosed with BA by surgical intervention and 139 patients were either healthy controls or had non-BA diagnoses. In this study, a total of 1,976 original US images were enrolled. Among them, 417 and 1,559 raw images were from patients with BA and without BA, respectively. Meanwhile, ShuffleNet achieved the highest accuracy of 90.56% using the same training parameters as compared with other network models. The sensitivity and specificity were 67.83% and 96.76%, respectively. In addition, the undesired false-negative prediction was prevented by applying positive-dominance law to interpret different images of a single patient with an acceptable false-positive rate, which was 13.64%. For the three consecutive patients with delayed obstructive jaundice with IOC confirmed diagnoses, ShuffleNet achieved accurate diagnoses in two patients.

Conclusion

The current study provides a screening tool for identifying possible BA by hepatobiliary US images. The method was not designed to replace liver biopsy or IOC, but to decrease human error for interpretations of US. By applying the positive-dominance law to ShuffleNet, the false-negative rate and the specificities were 0 and 86.36%, respectively. The trained deep learning models could aid physicians other than pediatric surgeons, pediatric gastroenterologists, or pediatric radiologists, to prevent misreading pediatric hepatobiliary US images. The current artificial intelligence (AI) tool is helpful for screening BA in the real world.

[Diagnostic Imaging of Biliary Atresia]

Biliary atresia is a rare but significant cause of neonatal cholestasis. An early and accurate diagnosis is important for proper management and prognosis. To diagnose biliary atresia, various imaging studies using ultrasonography, MRI, hepatobiliary scans, and cholangiography can be performed, although ultrasonography is more important for initial imaging studies. In this article, we review the findings of biliary atresia from various imaging modalities, including ultrasonography, MRI, hepatobiliary scans, and cholangiography. The known key imaging features include abnormal gallbladder size and shape, periportal thickening visible as a 'triangular cord' sign, invisible common bile duct, increased hepatic arterial flow, and combined anomalies. Aside from the imaging findings of biliary atresia, we also reviewed the diagnostic difficulty in the early neonatal period and the role of imaging in predicting hepatic fibrosis. We hope that this review will aid in the diagnosis of biliary atresia.

['Triangular Cord' Sign in Biliary Atresia]

Biliary atresia is an unknown etiology of extrahepatic bile duct obstruction with a 'fibrous ductal remnant,' which represents the obliterated ductal remnant in the porta hepatis. The sonographic'triangular cord' (TC) sign has been reported to indicate a fibrous ductal remnant in the porta hepatis. In this review, we discuss the correlations among surgicopathological and sonographic findings of the porta hepatis and the definition, objective criteria, diagnostic accuracy, and differential diagnosis of the TC sign in biliary atresia.

Development and validation of a novel nomogram and risk score for biliary atresia in patients with cholestasis

BACKGROUND

Timely discriminating biliary atresia (BA) from other causes of cholestasis is important but challenging.

AIMS

To develop a useful diagnostic nomogram and a simplified scoring system to diagnosing BA.

STUDY DESIGN

All medical records of the patients who were consecutively admitted to our institution with cholestasis from March 2016 to December 2020 were retrospectively searched. The patients were allocated to the derivation cohort (n = 343) and the validation cohort (n = 246). Multivariable logistic regression models were used to construct the nomogram. The nomogram was validated in both cohorts. The simplified risk score was derived from the nomogram.

RESULTS

The nomogram was constructed based on presence of clay stool, gallbladder length, gallbladder emptying index, shear wave elastography value, and gamma-glutamyl transferase level. This model showed good calibration and discrimination ability, with the C-index of 0.968 (95% CI: 0.951-0.984). The discriminating ability is most prominent in the 61-90 days group, with AUC of 0.982 (95% CI: 0.955-1.000). The simplified risk score identified most patients with very high or low risk of BA, and was capable of exempting 64.3% non-BA patients from intraoperative cholangiogram procedure.

CONCLUSIONS

This novel diagnostic nomogram had good discrimination and calibration abilities. The simplified scoring system showed significant clinical utility.

Biliary atresia and congenital disorders of the extrahepatic bile ducts

Biliary atresia (BA) and choledochal cysts are diseases of the intrahepatic and extrahepatic biliary tree. While their exact etiopathogeneses are not known, they should be treated promptly due to the potential for irreversible parenchymal liver disease. A diagnosis of BA may be easy or complicated, but should not be delayed. BA is always treated surgically, and performing the surgery before the age of 2 mo greatly increases its effectiveness and extends the time until the need for liver transplantation arises. While the more common types of choledochal cysts require surgical treatment, some can be treated with endoscopic retrograde cholangiopancreatography. Choledochal cysts may cause recurrent cholangitis and the potential for malignancy should not be ignored.

A nomogram model based on preoperative grey-scale US features and routine serum biomarkers to predict the outcome of infants with biliary atresia after Kasai portoenterostomy

OBJECTIVE

To establish a nomogram to predict the outcome of biliary atresia (BA) infants 3-months post- Kasai portoenterostomy (KPE).

METHODS

BA Infants who underwent KPE from two hospitals were included in the training (n = 161) and validation cohorts (n = 64). A logistic regression equation (Equation A) for predicting the serum total bilirubin (TBIL) level 3-month post-KPE was established in the training cohort. Then, a nomogram was developed based on Equation A in the training cohort and validated in the validation cohort. Moreover, a new equation (Equation B) was generated based on the nomogram and the size of the enlarged hilar lymph nodes (LNs) in the validation cohort. The predictive performance of the nomogram was evaluated by the receiver operating characteristic (ROC) curve and by calculating the area under the ROC curve (AUC), sensitivity, specificity, and positive (PPV) and negative (NPV) prediction values.

RESULTS

A nomogram based on gallbladder morphology and serum levels of TBIL and total protein (TP) was established with AUC (95%CI) of 0.673 (0.595, 0.745) and 0.647 (0.518, 0.763), sensitivity (95%CI) of 71.4% (62.1%,79.6%) and 81.8% (59.7%,94.8%), specificity (95%CI) of 63.3% (48.3%,76.6%) and 47.6% (32.0%,63.6%), PPV (95%CI) of 81.6% (72.5%,88.9%) and 45.0% (29.3%,61.5%), and NPV (95%CI) 49.2% (36.4%,62.1%) and 83.3% (62.6%,95.3%), respectively, in the training and validation cohorts. Furthermore, in the validation cohort, the AUC (95%CI) of Equation B was 0.798 (95%CI: 0.679, 0.888), which was significantly higher than that of the nomogram (P = 0.042).

CONCLUSION

A nomogram based on the pre-KPE gallbladder morphology, TBIL, and TP to predict the outcome of BA 3-months post-KPE is established. Moreover, the addition of the size of the enlarged hilar LNs into the nomogram further improves its predictive value.

Ultrasound for the Diagnosis of Biliary Atresia: From Conventional Ultrasound to Artificial Intelligence

Biliary atresia is an aggressive liver disease of infancy and can cause death without timely surgical intervention. Early diagnosis of biliary atresia is critical to the recovery of bile drainage and long-term transplant-free survival. Ultrasound is recommended as the initial imaging strategy for the diagnosis of biliary atresia. Numerous ultrasound features have been proved helpful for the diagnosis of biliary atresia. In recent years, with the help of new technologies such as elastography ultrasound, contrast-enhanced ultrasound and artificial intelligence, the diagnostic performance of ultrasound has been significantly improved. In this review, various ultrasound features in the diagnosis of biliary atresia are summarized. A diagnostic decision flow chart for biliary atresia is proposed on the basis of the hybrid technologies, combining conventional ultrasound, elastography and contrast-enhanced ultrasound. In addition, the application of artificial intelligence in the diagnosis of biliary atresia with ultrasound images is also introduced.

Latest diagnostic performance of different ultrasonic features for biliary atresia

BACKGROUND

Early diagnosis of biliary atresia (BA) is an important clinical challenge.

PURPOSE

To summarize the latest diagnostic performance of different ultrasonic (US) features for BA.

MATERIAL AND METHODS

MeSH terms "biliary atresia" and "ultrasonography" and related hyponyms were used to search PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Eligible articles were included and data were retrieved. The methodologic quality was assessed by version 2 of the Quality Assessment of Diagnostic Accuracy Studies tool. Estimated sensitivity and specificity of each US feature were calculated by Stata 14.0.

RESULTS

Fifty eligible studies on 5622 patients were included. Respective summary sensitivity and specificity were 77% (95% CI=69-84) and 98% (95% CI=96-99) for triangular cord sign (TCS) in 32 studies, 86% (95% CI=78-92) and 86% (95% CI=72-94) for shear wave elastography (SWE) in seven studies, 75% (95% CI=65-83) and 92% (95% CI=86-95) for gallbladder and biliary system abnormality (GBA) in 25 studies, and 81% (95% CI=69-90) and 79% (95% CI=67-87) for hepatic artery (HA) enlargement in seven studies. The overall US features from 11 studies yielded a summary sensitivity of 84% (95% CI=72-92) and specificity of 86% (95% CI=77-92).

CONCLUSION

TCS and GBA were the two most widely accepted US features currently used for differential diagnosis of BA. The newly developed SWE was an objective and convenient method with good diagnostic performance. HA enlargement can be used as an auxiliary sign.

Neonatal Cholestasis: Updates on Diagnostics, Therapeutics, and Prevention

Cholestatic jaundice is a common presenting feature of hepatobiliary and/or metabolic dysfunction in the newborn and young infant. Timely detection of cholestasis, followed by rapid step-wise evaluation to determine the etiology, is crucial to identify those causes that are amenable to medical or surgical intervention and to optimize outcomes for all infants. In the past 2 decades, genetic etiologies have been elucidated for many cholestatic diseases, and next-generation sequencing, whole-exome sequencing, and whole-genome sequencing now allow for relatively rapid and cost-effective diagnosis of conditions not previously identifiable via standard blood tests and/or liver biopsy. Advances have also been made in our understanding of risk factors for parenteral nutrition-associated cholestasis/liver disease. New lipid emulsion formulations, coupled with preventive measures to decrease central line-associated bloodstream infections, have resulted in lower rates of cholestasis and liver disease in infants and children receiving long-term parental nutrition. Unfortunately, little progress has been made in determining the exact cause of biliary atresia. The median age at the time of the hepatoportoenterostomy procedure is still greater than 60 days; consequently, biliary atresia remains the primary indication for pediatric liver transplantation. Several emerging therapies may reduce the bile acid load to the liver and improve outcomes in some neonatal cholestatic disorders. The goal of this article is to review the etiologies, diagnostic algorithms, and current and future management strategies for infants with cholestasis.

Development and Validation of a Nomogram Incorporating Ultrasonic and Elastic Findings for the Preoperative Diagnosis of Biliary Atresia

RATIONALE AND OBJECTIVES

To develop and validate a nomogram that incorporates the gallbladder morphology, hepatic elasticity, and demographic information for the prediction of biliary atresia (BA) in children.

MATERIALS AND METHODS

A total of 294 consecutive patients under the age of 70 days with cholestasis and suspected symptoms of BA were enrolled in this study, who were divided into a training cohort (150 patients) and a validation cohort (144 patients). Ultrasonography and two-dimensional shear wave elastography were performed for each patient prior to knowing the final diagnosis. Multivariate logistic regression was used to analyze the gallbladder morphologic feature in the sonogram (absence of gallbladder, small gallbladder, lower postprandial gallbladder contractibility, or abnormal gallbladder wall), hepatic elasticity and clinical data from the training cohort, and a diagnostic nomogram for BA was subsequently developed. The performance of the nomogram was respectively evaluated with respect to the discrimination and calibration in every cohort.

RESULTS

The multivariate analysis showed that the factors of age (p = 0.009), gallbladder morphology (p = 0.001) and hepatic elasticity (p < 0.001) could serve as independent predictive factors to differentiate between BA and other causes of cholestasis. The nomogram incorporating these three parameters showed good discrimination and satisfactory calibration, indicating a better performance compared to using only the gallbladder morphologic features and hepatic elasticity. The observed area under the receiver operator characteristic curve in the training cohort and validation cohort was 0.939 (p < 0.001) and 0.942 (p < 0.001), respectively, with a sensitivity of 95.5% and a specificity of 83.4% in the combined cohort.

CONCLUSION

The established nomogram shows a favored and improved predictive value for the diagnosis of BA.

Ultrasound characteristics combined with gamma-glutamyl transpeptidase for diagnosis of biliary atresia in infants less than 30 days

PURPOSE

To retrospectively assess the diagnostic performance of grey-scale ultrasound (US) characteristics and gamma-glutamyl transpeptidase (GGT) alone or combined in distinguishing biliary atresia (BA) from other cholestasis diseases in infants younger than 30 days.

MATERIALS AND METHODS

Between January 2012 and October 2020, the demographic characteristics, laboratory results and US characteristics of 35 BA and 52 non-BA infants younger than 30 days were retrospectively evaluated. Areas under the receiver operating characteristic curves (AUCs) were used to estimate the probability of predicting BA, which were compared by DeLong test.

RESULTS

The diagnostic performance of gallbladder classification in identifying BA was higher than that of fibrotic cord thickness (AUC 0.900 vs. 0.771, P = 0.03). With the cutoff level of 188 IU/L, serum GGT had a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 77.1%, 69.2%, 62.8%, and 81.8%, respectively. Combined with gallbladder classification and GGT, the sensitivity, specificity, PPV, NPV and accuracy were 100.0%, 63.5%, 64.8%, 100.0% and 78.2%.

CONCLUSIONS

Gallbladder classification was more valuable than fibrotic cord thickness in the diagnosis of BA among infants less than 30 days. Combined with gallbladder classification and GGT, the sensitivity for the diagnosis of BA can reach 100.0%.

Outcomes of late Kasai portoenterostomy in biliary atresia: a single-center experience

OBJECTIVES

To describe the clinical, histopathologic, and outcomes data for a cohort of patients with biliary atresia (BA), and to identify the factors affecting survival.

METHODS

This was a cross-sectional study of all BA patients diagnosed between 1999 and 2017. Clinical, biochemical, imaging, and histopathologic data were analyzed, and Kaplan-Meier survival rates were compared to identify potential prognostic factors.

RESULTS

We evaluated 23 patients. The median age at the Kasai procedure was 77 ± 34 days, and the median overall survival was 12.5 ± 65 months. Thirteen (56%) patients survived with their native livers, 3 (13%) received a transplant, and 6 died (26%) while awaiting a transplant. Cholangitis and the use of ursodeoxycholic acid were associated with longer survival, while impaired synthetic function was associated with shorter survival.

CONCLUSIONS

Most patients presented late for the Kasai procedure. The survival rate with the native liver was comparable to other cohorts. Therefore, clinicians are encouraged to refer for the Kasai procedure even with late presentation (between 60 and 90 days), provided there is no hepatic decompensation.

Ensembled deep learning model outperforms human experts in diagnosing biliary atresia from sonographic gallbladder images

It is still challenging to make accurate diagnosis of biliary atresia (BA) with sonographic gallbladder images particularly in rural area without relevant expertise. To help diagnose BA based on sonographic gallbladder images, an ensembled deep learning model is developed. The model yields a patient-level sensitivity 93.1% and specificity 93.9% [with areas under the receiver operating characteristic curve of 0.956 (95% confidence interval: 0.928-0.977)] on the multi-center external validation dataset, superior to that of human experts. With the help of the model, the performances of human experts with various levels are improved. Moreover, the diagnosis based on smartphone photos of sonographic gallbladder images through a smartphone app and based on video sequences by the model still yields expert-level performances. The ensembled deep learning model in this study provides a solution to help radiologists improve the diagnosis of BA in various clinical application scenarios, particularly in rural and undeveloped regions with limited expertise.

Practical approach to imaging diagnosis of biliary atresia, Part 1: prenatal ultrasound and magnetic resonance imaging, and postnatal ultrasound

We present a practical approach to imaging in suspected biliary atresia, an inflammatory cholangiopathy of infancy resulting in progressive fibrosis and obliteration of extrahepatic and intrahepatic bile ducts. Left untreated or with failure of the Kasai procedure, biliary atresia progresses towards biliary cirrhosis, end-stage liver failure and death by age 3. Differentiation of biliary atresia from other nonsurgical causes of neonatal cholestasis is challenging because there is no single method for diagnosing biliary atresia, and clinical, laboratory and imaging features of this disease overlap with those of other causes of neonatal cholestasis. Concerning imaging, our systematic literature review shows that ultrasonography is the main tool for pre- and neonatal diagnosis. Key prenatal features, when present, are non-visualisation of the gallbladder, cyst in the liver hilum, heterotaxy syndrome and irregular gallbladder walls. Postnatal imaging features have a very high specificity when present, but a variable sensitivity. Triangular cord sign and abnormal gallbladder have the highest sensitivity and specificity. The presence of macro- or microcyst or polysplenia syndrome is highly specific but less sensitive. The diameter of the hepatic artery and hepatic subcapsular flow are less reliable. When present in the context of acholic stools, dilated intrahepatic bile ducts rule out biliary atresia. Importantly, a normal US exam does not rule out biliary atresia. Signs of chronic hepatopathy and portal hypertension (portosystemic derivations such as patent ductus venosus, recanalised umbilical vein, splenomegaly and ascites) should be actively identified for - but are not specific for - biliary atresia.

The Utility of Gallbladder Absence on Ultrasound for Children With Biliary Atresia

Background: Biliary Atresia (BA) is congenital condition, where infant intra- and extrahepatic bile ducts become obliterated, leading to cholestasis, and cirrhosis if untreated. This study aims to assess the predictive measure of absent gallbladder on ultrasounds (US) performed in infants with cholestasis for diagnosing BA. Method: After Institutional Review Board approval, retrospective chart reviews of 61 infants with cholestasis found 43 (70.5%) were diagnosed with BA. A pediatric radiologist provided interpretations of all ultrasounds in a blinded fashion. Statistical analysis was used to assess the utility of absence of gallbladder on US in predicting BA, confirmed intraoperatively. Results: Absent gallbladder on US predicts absent gallbladder with 77% accuracy, 92% sensitivity, 73% specificity, PPV 43%, and NPV 97% (P < 0.001, Fisher exact test). To diagnose BA, absent gallbladder on US has 66% accuracy, 53% sensitivity, 94% specificity, 96% PPV, and 46% NPV (P < 0.001, Fisher exact test). Conclusion: Sonographic gallbladder absence has high specificity and PPV, indicating utility for BA diagnosis; however, it is not useful for ruling out BA given its low sensitivity.

Recent developments in diagnostics and treatment of neonatal cholestasis

Neonatal cholestasis is characterized by conjugated hyperbilirubinemia in the newborn and young infant and is a sign common to over 100 hepatobiliary and/or metabolic disorders. A timely evaluation for its etiology is critical in order to quickly identify treatable causes such as biliary atresia, many of which benefit from early therapy. An expanding group of molecularly defined disorders involving bile formation, canalicular transporters, tight junction proteins and inborn errors of metabolism are being continuously discovered because of advances in genetic testing and bioinformatics. The advent of next generation sequencing has transformed our ability to test for multiple genes and whole exome or whole genome sequencing within days to weeks, enabling rapid and affordable molecular diagnosis for disorders that cannot be directly diagnosed from standard blood tests or liver biopsy. Thus, our diagnostic algorithms for neonatal cholestasis are undergoing transformation, moving genetic sequencing to earlier in the evaluation pathway once biliary atresia, "red flag" disorders and treatable disorders are excluded. Current therapies focus on promoting bile flow, reducing pruritus, ensuring optimal nutrition, and monitoring for complications, without addressing the underlying cause of cholestasis in most instances. Our improved understanding of bile formation and the enterohepatic circulation of bile acids has led to emerging therapies for cholestasis which require appropriate pediatric clinical trials. Despite these advances, the cause and optimal therapy for biliary atresia remain elusive. The goals of this review are to outline the etiologies, diagnostic pathways and current and emerging management strategies for neonatal cholestasis.

Gut Microbiota Dysbiosis Associated with Bile Acid Metabolism in Neonatal Cholestasis Disease

Neonatal cholestasis disease (NCD) is a complex and easily mis-diagnosed condition. We analyzed microbiota community structure in feces and measured short-chain fatty acids, bile acids (BAs) and liver function of 12 healthy, 13 NCD, and 13 treated infants after diagnosis. Based on 16S rRNA gene amplicon sequencing and gas-chromatographic-mass-spectrometric analysis of secondary BAs, we identified microbial genera and metabolites that associate with abnormal bile secretion. Streptococcus gallolyticus and Parabacteroides distasonis, and Lactobacillus gasseri had higher relative abundance in healthy and NCD infants respectively. Compared to NCD patients, healthy infants had higher LCA, CDCA and GCDCA fecal concentrations. The three microbial species and three secondary bile acids were selected as potential non-invasive combined biomarkers to diagnose NCD. We propose that microbiota-metabolite combined biomarkers could be used for diagnosis of NCD, and this may contribute to improved early clinical diagnosis of NCD in the future.

Ultrasound findings in paediatric cholestasis: how to image the patient and what to look for

Paediatric biliary tract and gallbladder diseases include a variety of entities with a wide range of clinical presentations. Cholestasis represents an impaired secretion of bilirubin by hepatocytes, manifesting with high blood levels of conjugated bilirubin and jaundice. Various causes may be involved, which can be recognised analysing blood tests and hepatobiliary imaging, while sometimes liver biopsy or surgery may be necessary. High-resolution real-time ultrasonography is an important tool for differentiation of obstructive and non-obstructive causes of jaundice in infants and children. In this paper, we briefly review the normal anatomy and the ultrasound aspects of main pathologies affecting gallbladder and biliary tree in neonatal and paediatric age.

Is "gallbladder length-to-width ratio" useful in diagnosing biliary atresia?

BACKGROUND

The accurate assessment of gallbladder shape and wall abnormalities by ultrasound (US) in diagnosing biliary atresia (BA) remains a subjective determination. The objective of this study was to examine the reliability of gallbladder length-to-width ratio (LTWR) by US measurement for diagnosis of BA.

METHODS

One hundred infants with conjugated hyperbilirubinemia and unknown cause of jaundice who underwent transabdominal US from February 2009 to February 2017 were enrolled. The gallbladder classification and other detailed US findings were reviewed.

RESULTS

There were statistical differences in gallbladder lumen, classification, length, width and LTWR of gallbladder (all P < 0.05) between BA and non-BA groups. The gallbladder LTWR with a cutoff at 4.1 had the highest sensitivity of 71.7%, while the fibrotic cord thickness had the highest specificity of 95.9%. The combination of portal vein (PV) diameter > 4.4 mm, hepatic artery (HA) diameter > 1.2 mm, and gallbladder LTWR >4.1, provided much higher specificity (98%), odds ratio (11), and positive likelihood ratio (LR+) (10.6).

CONCLUSION

The gallbladder LTWR by US could be a suggestive US parameter for BA screening. The triad of PV diameter, HA diameter, and gallbladder LTWR yielded the highest specificity, odds ratio, and LR+ for diagnosing BA.

LEVEL OF EVIDENCE

Level III study of diagnostic test.

Does Supersonic Shear Wave Elastography Help Differentiate Biliary Atresia from Other Causes of Cholestatic Hepatitis in Infants Less than 90 Days Old? Compared with Grey-Scale US

Purpose

To investigate the diagnostic performance of shear wave elastography (SWE) for measuring liver stiffness to identify and differentiate biliary atresia (BA) from cholestatic hepatitis in infants younger than 90 days.

Methods

A total of 138 infants younger than 90 days with cholestatic hepatitis were examined by SWE. The infants were subclassified into BA and nonbiliary atresia (non-BA) groups. Receiver operating characteristic (ROC) analysis was used to determine the sensitivity and specificity of hepatic Young's modulus measurements, the ultrasonic findings in the differential diagnosis of suspected BA, and the cut-off value to diagnose BA.

Results

In all infants with cholestatic hepatitis, the cut-off value of hepatic Young's modulus to differentiate the BA group from the non-BA group was 12.35 kPa and the area under the ROC curve (AUC) was 0.937, with a sensitivity of 84.3% and a specificity of 89.7%; nevertheless the AUC of the abnormal gallbladder (AbGB) was 0.940, with a sensitivity of 96.1% and a specificity of 92.0%. In the parallel test, triangular cord (TC) sign combined with AbGB had the best diagnostic performance and the AUC was 0.960, with a sensitivity of 100% and a specificity of 92.0%. In the serial test, SWE combined with AbGB achieved the best diagnostic performance; the AUC was 0.902, the sensitivity and specificity were 80.4% and 100%, respectively.

Conclusions

SWE could not only help differentiate BA from cholestatic hepatic diseases but also increase the diagnostic specificity when combined with grey-scale ultrasound in the serial test.

Neonatal cholestasis: emerging molecular diagnostics and potential novel therapeutics

Neonatal cholestasis is a group of rare disorders of impaired bile flow characterized by conjugated hyperbilirubinaemia in the newborn and young infant. Neonatal cholestasis is never physiological but rather is a sign of hepatobiliary and/or metabolic disorders, some of which might be fatal if not identified and treated rapidly. A step-wise timely evaluation is essential to quickly identify those causes amenable to treatment and to offer accurate prognosis. The aetiology of neonatal cholestasis now includes an expanding group of molecularly defined entities with overlapping clinical presentations. In the past two decades, our understanding of the molecular basis of many of these cholestatic diseases has improved markedly. Simultaneous next-generation sequencing for multiple genes and whole-exome or whole-genome sequencing now enable rapid and affordable molecular diagnosis for many of these disorders that cannot be directly diagnosed from standard blood tests or liver biopsy. Unfortunately, despite these advances, the aetiology and optimal therapeutic approach of the most common of these disorders, biliary atresia, remain unclear. The goals of this Review are to discuss the aetiologies, algorithms for evaluation and current and emerging therapeutic options for neonatal cholestasis.

Management options for cholestatic liver disease in children

Due to a peculiar age-dependent increased susceptibility, neonatal cholestasis affects the liver of approximately 1 in every 2500 term infants. A high index of suspicion is the key to an early diagnosis, and to implement timely, often life-saving treatments. Even when specific treatment is not available or curative, prompt medical management and optimization of nutrition are of paramount importance to survival and avoidance of complications. Areas covered: The present article will prominently focus on a series of newer diagnostic and therapeutic options of cholestasis in neonates and infants blended with consolidated established paradigms. The overview of strategies for the management reported here is based on a systematic literature search published in English using accessible databases (PubMed, MEDLINE) with the keywords biliary atresia, choleretics and neonatal cholestasis. References lists from retrieved articles were also reviewed. Expert commentary: A large number of uncommon and rare hepatobiliary disorders may present with cholestasis during the neonatal and infantile period. Potentially life-saving disease-specific pharmacological and surgical therapeutic approaches are currently available. Advances in hepatobiliary transport mechanisms have started clarifying fundamental aspects of inherited and acquired cholestasis, laying the foundation for the development of possibly more effective specific therapies.

Diagnostic Performance of Sonographic Features in Patients With Biliary Atresia: A Systematic Review and Meta-analysis

OBJECTIVES

To evaluate the diagnostic performance of sonographic features of biliary atresia in patients with infantile cholestasis.

METHODS

The Ovid-MEDLINE and EMBASE databases were searched for studies of the diagnostic performance of sonographic features of biliary atresia in patients with infantile cholestasis. A meta-analysis was performed to evaluate the diagnostic performance of the triangular cord sign and other sonographic features in patients with biliary atresia.

RESULTS

Seventeen eligible studies with 1444 patients were included. The triangular cord sign had high accuracy for diagnosing biliary atresia: the meta-analytic summary sensitivity and specificity were 85% (95% confidence interval, 77%-90%) and 97% (95% confidence interval, 94%-99%), respectively. The area under the hierarchical summary receiver operating characteristic curve was 0.97. Meta-regression analysis revealed that the cutoff thickness of the triangular cord sign (3 or 4 mm) was a significant factor affecting study heterogeneity (P < .01). The proportions of nonidentification of the gallbladder (GB) ranged from 0% to 53%. Abnormal GB morphologic characteristics, nonvisualization of the common bile duct, and the presence of hepatic subcapsular flow showed relatively high sensitivities and specificities.

CONCLUSIONS

The triangular cord sign and other sonographic features, including abnormal GB morphologic characteristics, nonvisualization of the common bile duct, and the presence of hepatic subcapsular flow, had high diagnostic performance for the diagnosis of biliary atresia.

Role of Hepatobiliary Scintigraphy and Preoperative Liver Biopsy for Exclusion of Biliary Atresia in Neonatal Cholestasis Syndrome

All diagnostic algorithms for Neonatal Cholestasis Syndrome (NCS) focus on differentiating numerous medical causes from Biliary Atresia (BA). No preoperative diagnostic algorithm has 100% diagnostic accuracy for BA and yet, timely diagnosis is crucial to optimize surgical outcome. Markers for high index of clinical suspicion for BA are: a "usually" well thriving infant with conjugated hyperbilirubinemia, raised gamma glutamyl transpeptidase, persistently "acholic" stools, firm hepatomegaly with dysmorphic, hypoplastic gall bladder. In the presence of above 'red flag' signs, there has been much debate on diagnostic accuracy of percutaneous liver biopsy (PLB) vs. hepatobiliary scintigraphy (HBS) to substantiate or exclude BA. Recent guidelines suggest a shift towards PLB (91.6% overall diagnostic accuracy) as the diagnostic cornerstone with key differentiating feature being 'bile ductular proliferation'. HBS has a high (98.7%) sensitivity but low specificity (37-74%) with an overall diagnostic accuracy of 67% for BA. Severe hepatocellular disease without anatomic obstruction would also have a non-excretory scan. Thus, while excretory HBS excludes BA, non-excretion does not confirm BA. Hence, diagnostic algorithms relying on non-excretory HBS as the primary standalone benchmark for surgical exploration would be mired by a high negative laparotomy rate revealing a normal peroperative cholangiogram (POC). However, an excretory HBS obviates need for laparotomy in case of equivocal stool color or PLB. A POC continues to be the ultimate gold standard. Hence, with high index of clinical suspicion but equivocal ultrasonography or PLB and a non-excretory HBS, the baby should not be denied a POC within time frame crucial for successful hepatoportoenterostomy.

Prenatal diagnosis of biliary atresia: A case series

BACKGROUND

Biliary atresia is a progressive disease presenting with jaundice, and is the most common indication for liver transplantation in the pediatric population. Prenatal series have yielded conflicting results concerning a possible association between BA and prenatal nonvisualization of the gallbladder.

AIMS

This retrospective case series was performed to assess the association between biliary atresia, prenatal nonvisualization of the gallbladder and other sonographic signs.

STUDY DESIGN/SUBJECTS

We identified biliary atresia patients who underwent a Kasai procedure by a single pediatric surgeon and/or follow up by a single pediatric gastroenterologist. Axial plane images and/or video recordings were scrutinized for sonographic signs of biliary atresia on the second trimester anomaly scan.

OUTCOME MEASURES

Proportion of biliary atresia cases with prenatal sonographic signs.

RESULTS

Twenty five charts of children with biliary and high quality prenatal images were retrieved. 6/25 (24%) of cases analyzed had prenatal nonvisualization of the gallbladder or a small gallbladder on the prenatal scan. Two cases had biliary atresia splenic malformation syndrome. None of the cases had additional sonographic markers of biliary atresia.

CONCLUSIONS

Our study suggests that in addition to the well-established embryonic and cystic forms, an additional type can be suspected prenatally, which is characterized by prenatal nonvisualization of the gallbladder in the second trimester. This provides additional evidence that some cases of BA are of fetal rather than perinatal onset and may have important implications for prenatal diagnosis, for counseling and for research of the disease's etiology and pathophysiology.

Ultrasound of congenital and inherited disorders of the pediatric hepatobiliary system, pancreas and spleen

Ultrasound is often the initial imaging examination performed of the solid organs of the pediatric abdomen. The sonographic appearance of the hepatobiliary system, pancreas and spleen changes with growth and development. This article reviews the normal US appearance of these organs in children and illustrates, through case examples, congenital and inherited conditions that affect them.

Imaging findings of Alagille syndrome in young infants: differentiation from biliary atresia

OBJECTIVE

To compare the imaging findings using ultrasonography, MR cholangiopancreatography (MRCP), and intraoperative cholangiography (IOC) between Alagille syndrome (AGS) and biliary atresia (BA) in young infants with cholestatic jaundice.

METHODS

The institutional review board approved this retrospective study. Ultrasonography (n = 55), MRCP (n = 33), and IOC (n = 22) studies were performed in 55 infants (all younger than 3 months) with AGS (n = 7) and BA (n = 48). The ultrasound images were reviewed focusing on gallbladder (GB) abnormalities, triangular cord sign, hepatic artery enlargement and signs of portal hypertension. Visualization of the extrahepatic biliary tree was assessed by MRCP and IOC.

RESULTS

Six (86%) AGS patients showed a small GB on ultrasound; this was comparable to that in BA patients (81%, 35/43). The images were negative for triangular cord sign and hepatic artery enlargement in all AGS patients, whereas they were positive in 48% (23/48) (p = 0.034) and 77% (33/43) (p < 0.001) of the BA patients, respectively. Signs of portal hypertension were less common in AGS patients than in BA patients (p = 0.010). Although non-visualization of the extrahepatic biliary tree by MRCP did not differ significantly between patients with AGS and BA, AGS patients showed a higher proportion of visible common bile ducts with IOC, compared to BA patients. The diagnosis of AGS was made in four infants (57%) before ultrasonography, based on extrahepatic manifestations.

CONCLUSION

The small GB visualized on ultrasonography and non-visualization of extrahepatic biliary tree by MRCP commonly occurred in patients with either AGS or BA. However, triangular cord sign, hepatic artery enlargement and signs of portal hypertension onultrasonography and non-visualized common bile duct with IOC were less frequent in AGS patients than in BA patients. Advances in knowledge: Atypical imaging findings for BA should prompt a meticulous evaluation for the extrahepatic manifestations of AGS to avoid possibly harmful surgery.

Liver stiffness measurements with supersonic shear wave elastography in the diagnosis of biliary atresia: a comparative study with grey-scale US

OBJECTIVES

To prospectively assess the diagnostic performance of supersonic shear wave elastography (SSWE) in identifying biliary atresia (BA) among infants with conjugated hyperbilirubinaemia by comparing this approach with grey-scale ultrasonography (US).

METHODS

Forty infants were analysed as the control group to determine normal liver stiffness values. The use of SSWE values for identifying BA was investigated in 172 infants suspected of having BA, and results were compared with the results obtained by grey-scale US. The Mann-Whitney U test, unpaired t-test, Spearman correlation and linear regression were also performed.

RESULTS

The success rates of SSWE measurements in the control and study group were 100% (40/40) and 96.4% (244/253), respectively. Age, direct bilirubin, and indirect bilirubin all significantly correlated with SSWE in the liver (all P < 0.001). Linear regression showed that age had a greater effect on SSWE values than direct or indirect bilirubin. The diagnostic performance of liver stiffness values in identifying BA was lower than that of grey-scale US (area under the receiver operating characteristic curve [AUC], 0.790 vs 0.893, P < 0.001).

CONCLUSIONS

SSWE is feasible and valuable in differentiating BA from non-BA. However, its diagnostic performance does not exceed that of grey-scale US.

KEY POINTS

• SSWE could be successfully performed in an infant population. • For infants, the liver stiffness will increase as age increases. • SSWE is potentially useful in assessing infants suspected of biliary atresia. • SSWE is inferior to grey-scale US in identifying biliary atresia.

Guideline for the Evaluation of Cholestatic Jaundice in Infants: Joint Recommendations of the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition

Cholestatic jaundice in infancy affects approximately 1 in every 2500 term infants and is infrequently recognized by primary providers in the setting of physiologic jaundice. Cholestatic jaundice is always pathologic and indicates hepatobiliary dysfunction. Early detection by the primary care physician and timely referrals to the pediatric gastroenterologist/hepatologist are important contributors to optimal treatment and prognosis. The most common causes of cholestatic jaundice in the first months of life are biliary atresia (25%-40%) followed by an expanding list of monogenic disorders (25%), along with many unknown or multifactorial (eg, parenteral nutrition-related) causes, each of which may have time-sensitive and distinct treatment plans. Thus, these guidelines can have an essential role for the evaluation of neonatal cholestasis to optimize care. The recommendations from this clinical practice guideline are based upon review and analysis of published literature and the combined experience of the authors. The committee recommends that any infant noted to be jaundiced after 2 weeks of age be evaluated for cholestasis with measurement of total and direct serum bilirubin, and that an elevated serum direct bilirubin level (direct bilirubin levels >1.0 mg/dL or >17 μmol/L) warrants timely consideration for evaluation and referral to a pediatric gastroenterologist or hepatologist. Of note, current differential diagnostic plans now incorporate consideration of modern broad-based next-generation DNA sequencing technologies in the proper clinical context. These recommendations are a general guideline and are not intended as a substitute for clinical judgment or as a protocol for the care of all infants with cholestasis. Broad implementation of these recommendations is expected to reduce the time to the diagnosis of pediatric liver diseases, including biliary atresia, leading to improved outcomes.

Incremental Value of MR Cholangiopancreatography in Diagnosis of Biliary Atresia

Purpose

To evaluate the incremental value of a combination of magnetic resonance cholangiopancreatography (MRCP) and ultrasonography (US), compared to US alone, for diagnosing biliary atresia (BA) in neonates and young infants with cholestasis.

Materials and Methods

The institutional review board approved this retrospective study. The US and MRCP studies were both performed on 64 neonates and young infants with BA (n = 41) or without BA (non-BA) (n = 23). Two observers reviewed independently the US alone set and the combined US and MRCP set, and graded them using a five-point scale. Diagnostic performance was compared using pairwise comparison of the receiver operating characteristics (ROC) curve. The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value were assessed.

Results

The diagnostic performance (the area under the ROC curve [A_z]) for diagnosing BA improved significantly after additional review of MRCP images; A_z improved from 0.688 to 0.901 (P = .015) for observer 1 and from 0.676 to 0.901 (P = .011) for observer 2. The accuracy of MRCP combined with US (observer 1, 95% [61/64]; observer 2 92% [59/64]) and PPV (observer 1, 95% [40/42]; observer 2 91% [40/44]) were significantly higher than those of US alone for both observers (accuracy: observer 1, 73% [47/64], P = 0.003; observer 2, 72% [46/64], P = 0.004; PPV: observer 1, 76% [35/46], P = 0.016; observer 2, 76% [34/45], P = 0.013). Interobserver agreement of confidence levels was good for US alone (ĸ = 0.658, P < .001) and was excellent for the combined set of US and MRCP (ĸ = 0.929, P < .001).

Conclusion

Better diagnostic performance was achieved with the combination of US and MRCP than with US alone for the evaluation of BA in neonates and young infants with cholestasis.

Ultrasonography: Applications in Pediatric Abdomen

Ultrasonography (US) is a valuable imaging tool for evaluation of different clinical conditions in children, in general and abdominal conditions, in particular. The interest in US derives primarily from the lack of ionizing radiation exposure, low cost, portability, real-time imaging and Doppler capabilities. In addition, US application requires no preparation or sedation, making it particularly attractive in the pediatric population. Because of these advantages, US has been adopted as the primary imaging tool for evaluation of a number of pediatric abdominal conditions that would have involved the use of ionising radiation in the past, e.g., pyloric stenosis, intussusception and various renal and bladder abnormalities, to name a few. Certain limitations, however, are inherent to US including large body habitus, excessive bowel gas, postoperative state and the learning curve. In addition, pediatric US is particularly challenging as the children are frequently unable to co-operate for breath holding and many of them are crying during the scanning. In the present review, the authors discuss the various applications of US in the evaluation of pediatric abdomen.

Comparison of phenobarbitone and ursodeoxycholic acid in drug-augmented hepatobiliary scintigraphy for excluding the diagnosis of obstructive cholestasis in neonatal cholestasis syndrome

OBJECTIVES

Neonatal cholestasis is a common cause of jaundice among newborns. Hepatobiliary scintigraphy plays an important role in the diagnosis of neonatal cholestasis by ruling out extrahepatic biliary atresia, which is one of the common causes. Phenobarbitone and ursodeoxycholic acid (UDCA) have been used to improve the specificity of hepatobiliary scintigraphy in ruling out obstructive causes of neonatal cholestasis syndrome (NCS). The present study was undertaken to compare the utility of phenobarbitone and UDCA in augmenting hepatobiliary scintigraphy in the evaluation of NCS.

MATERIALS AND METHODS

Seventy-four consecutive patients with NCS referred for hepatobiliary scintigraphy were initially subjected to a baseline scan. Twenty patients showed tracer activity in the intestine within 24 h after injection, thus ruling out obstructive cholestasis. Fifty-four patients who did not show any tracer activity in the intestine were categorized as nonexcretors. Four nonexcretors were lost to follow-up and were excluded from the study. Fifty nonexcretors showing scan features suggestive of obstructive cholestasis were further randomized into those receiving phenobarbitone (n=20), UDCA (n=20), or placebo (n=10). These groups were further evaluated with drug-augmented hepatobiliary scintigraphy, after premedication, for any excretory activity in the intestine.

RESULTS AND CONCLUSION

Out of 50 patients who were evaluated with drug-augmented hepatobiliary scintigraphy two patients from the phenobarbitone group and one patient each from UDCA and placebo groups showed a change in excretory pattern from the baseline scan. However, these results were statistically nonsignificant (P=1.00). In the present study, drug-augmented (phenobarbitone or UDCA) hepatobiliary scintigraphy did not seem to improve the results (negative predictive value) for ruling out an obstructive cause of neonatal cholestasis.

Comparison of different noninvasive diagnostic methods for biliary atresia: a meta-analysis

BACKGROUND

This study was undertaken to retrospectively analyze the accuracy of different methods in differentiating biliary atresia from neonatal jaundice.

METHODS

A search was made in MEDLINE, and the Web of Science for relevant original articles published in English; methodological quality of the included studies was also assessed. Two reviewers extracted data independently. Studies were pooled, summary receiver operating characteristics curve and diagnostic odds ratio (DOR) with corresponding confidence intervals were calculated.

RESULTS

For diagnosis of biliary atresia, ultrasonography (US), hepatic scintigraphy (HBS), and magnetic resonance cholangiography (MRCP) had a pooled sensitivity of 74.9% (range: 70.4%-79.1%), 93.4% (range: 90.3%-95.7%) and 89.7% (range: 84.8%-93.4%), a specificity of 93.4% (range: 91.4%-95.1%), 69.2% (range: 65.1%-73.1%) and 64.7% (range: 58.0%-71.0%), a positive likelihood ratio of 12.16 (range: 6.41-23.08), 3.01 (range: 2.15-4.20) and 3.10 (range: 1.59-6.06), a negative likelihood ratio of 0.23 (range: 0.13-0.38), 0.13 (range: 0.06-0.25) and 0.16 (range: 0.06-0.44), DOR of 72.56 (range: 27.34-192.58), 29.88 (range: 12.82-69.64) and 32.48 (range: 8.22-128.29), with an area under the curve of 0.96, 0.91, and 0.92, and Q value of 0.90, 0.85, and 0.85, respectively.

CONCLUSIONS

US, HBS and MRCP can be very useful for the diagnostic work-up of neonatal cholestasis. To improve the sensitivity and specificity, several additional measures can be used.

Ultrasonographic Diagnosis of Biliary Atresia Based on a Decision-Making Tree Model

Objective

To assess the diagnostic value of various ultrasound (US) findings and to make a decision-tree model for US diagnosis of biliary atresia (BA).

Materials and Methods

From March 2008 to January 2014, the following US findings were retrospectively evaluated in 100 infants with cholestatic jaundice (BA, n = 46; non-BA, n = 54): length and morphology of the gallbladder, triangular cord thickness, hepatic artery and portal vein diameters, and visualization of the common bile duct. Logistic regression analyses were performed to determine the features that would be useful in predicting BA. Conditional inference tree analysis was used to generate a decision-making tree for classifying patients into the BA or non-BA groups.

Results

Multivariate logistic regression analysis showed that abnormal gallbladder morphology and greater triangular cord thickness were significant predictors of BA (p = 0.003 and 0.001; adjusted odds ratio: 345.6 and 65.6, respectively). In the decision-making tree using conditional inference tree analysis, gallbladder morphology and triangular cord thickness (optimal cutoff value of triangular cord thickness, 3.4 mm) were also selected as significant discriminators for differential diagnosis of BA, and gallbladder morphology was the first discriminator. The diagnostic performance of the decision-making tree was excellent, with sensitivity of 100% (46/46), specificity of 94.4% (51/54), and overall accuracy of 97% (97/100).

Conclusion

Abnormal gallbladder morphology and greater triangular cord thickness (> 3.4 mm) were the most useful predictors of BA on US. We suggest that the gallbladder morphology should be evaluated first and that triangular cord thickness should be evaluated subsequently in cases with normal gallbladder morphology.

Optimizing the US Diagnosis of Biliary Atresia with a Modified Triangular Cord Thickness and Gallbladder Classification

Purpose To evaluate the diagnostic performance of ultrasonography (US) in the identification and exclusion of biliary atresia with a modified triangular cord thickness metric together with a gallbladder classification scheme, as well as hepatic artery (HA) diameter and liver and spleen size, in a large sample of jaundiced infants. Materials and Methods The ethics committee approved this study, and written informed parental consent was obtained. In 273 infants with conjugated hyperbilirubinemia (total bilirubin level ≥ 31.2 μmol/L, with direct bilirubin level > indirect bilirubin level), detailed abdominal US was performed to exclude biliary atresia. Biliary atresia was found in 129 infants and ruled out in 144. A modified triangular cord thickness was measured at the anterior branch of the right portal vein, and a gallbladder classification scheme was identified that incorporated the appearance of the gallbladder and a gallbladder length-to-width ratio of up to 5.2 when the lumen was visualized, as well as HA diameter and liver and spleen size. Reference standard diagnosis was based on results of one or more of the following: surgery, liver biopsy, cholangiography, and clinical follow-up. Area under the receiver operating characteristic curve (AUC) analysis, binary logistic regression analysis, Fisher exact test, and unpaired t test were performed. Results Triangular cord thickness, HA diameter, ratio of gallbladder length to gallbladder width, liver size, and spleen size exhibited statistically significant differences (all P < .05) between the group with biliary atresia and the group without. AUCs of triangular cord thickness, ratio of gallbladder length to width, and HA diameter were 0.952, 0.844, and 0.838, respectively. Logistic regression analysis demonstrated that these three US parameters were significantly associated (all P < .05) with biliary atresia. The combination of triangular cord thickness and gallbladder classification could yield comparable AUCs (0.915 vs 0.933, P = .400) and a higher sensitivity (96.9% vs 92.2%), compared with triangular cord thickness alone. Conclusion By using the combination of modified triangular cord thickness and gallbladder classification scheme, most infants with biliary atresia could be identified. (©) RSNA, 2015.

Contribution of acoustic radiation force impulse (ARFI) elastography to the ultrasound diagnosis of biliary atresia

BACKGROUND

Children with biliary atresia rapidly develop liver fibrosis secondary to inflammatory destruction of the biliary tract. Noninvasive detection of liver fibrosis in neonatal/infantile cholestasis is an additional criterion for the diagnosis of biliary atresia, leading to prompt surgical exploration.

OBJECTIVE

To assess the value of US with acoustic radiation force impulse (ARFI) elastography to detect biliary atresia in the workup of neonatal/infantile cholestasis.

MATERIALS AND METHODS

In this retrospective study, 20 children with cholestasis suspected of having biliary atresia were investigated by US and ARFI. We evaluated the association between US findings and the diagnosis of biliary atresia and with two scores of liver fibrosis obtained from liver biopsy.

RESULTS

In univariate analyses, gallbladder size, triangular cord sign, spleen size and ARFI values were found to be associated with biliary atresia, though only the triangular cord sign remained significant when elevated gamma glutamyltransferase (GGT) was included as a predictor. In contrast, spleen size and ARFI correlated with the degree of liver fibrosis on biopsy (r > 0.70, P < 0.001), which remained significant when gamma glutamyltransferase elevation was included as a predictor.

CONCLUSION

The addition of ARFI to a standard abdominal US in the initial workup of the neonate with possible infantile cholestasis can provide reliable information on liver fibrosis and help in the diagnosis of biliary atresia.