Comparison of ultrasound and biopsy findings in children with cystic fibrosis related liver disease

Early detection of hepatobiliary involvement in cystic fibrosis: Biomarkers, radiologic methods, and genetic influences

Cystic fibrosis-related hepatobiliary involvement (CFHBI) is a term used to describe a spectrum of hepatobiliary involvement ranging from a transient elevation of transaminase levels to advanced cystic fibrosis-associated liver disease (aCFLD). While CFHBI is common among people with cystic fibrosis (PwCF), aCFLD is rare impacting only approximately 5%-10% of the CF population. After respiratory/cardiorespiratory issues and transplant-related complications, aCFLD is now the 4th leading cause of mortality among PwCF. Additionally, aCFLD is an independent predictor of all-cause mortality and is associated with significant morbidity. Despite this recognition, our ability to predict those patients at greatest risk for aCFLD, identify early aCFLD, and monitor the incremental progression of CFHBI is lacking. Here, we review the strengths and weaknesses of the common biomarkers and imaging modalities used in the evaluation and monitoring of CFHBI, as well as the current understanding of genetic modifiers related to aCFLD.

Cystic fibrosis hepatobiliary involvement: an update on imaging in diagnosis and monitoring

Analysis of the liver using imaging for persons with cystic fibrosis (CF) continues to evolve as new medical therapies are developed improving and extending life. In the 2010s, therapies targeted at modulating protein folding became available to those with CF. Therapeutic options have continued to expand, now providing both correction of protein folding and stabilization for most gene mutations that code for the CF transmembrane receptor protein (CFTR). Today, approximately 80% of persons with CF are eligible for highly effective modulator therapy. With these advancements, the impact of CF on the liver has become more complex, adding metabolism of CFTR modulators to intrinsic CF hepatobiliary involvement (CFHBI) and adding not previously appreciated vascular changes within the liver due to increased longevity in persons with CF. A combination of serum biomarkers and imaging is needed to add clarity to the diagnosis and monitoring of the severity of liver disease. A substantial portion of persons with CF will develop at least CFHBI and a subset will develop advanced cystic fibrosis-associated liver disease (aCFLD); therefore, diagnosis and monitoring need to begin in childhood. In this review, we cover the use of and need for imaging, including elastography, ultrasound, and magnetic resonance imaging (MRI), in diagnosing and monitoring CFHBI and its associated complications.

Cystic fibrosis liver disease in the new era of cystic fibrosis transmembrane conductance regulator (CFTR) modulators

Cystic fibrosis liver disease (CFLD) is characterised by a wide heterogenity of manifestations and severity. It represents a major cause of morbidity in people with cystic fibrosis (PwCF), which will be of increasing relevance as survival increases in the new era of cystic fibrosis care. No medical therapy currently available has evidence to treat or prevent progression of liver disease. Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) modulators may be transformative on pulmonary, nutritional and quality of life, but direct effect on long term liver disease outcomes is not yet established. Drug-associated hepatic adverse effects may be common, and clinician familiarity with drug-monitoring recommendations is essential. Longitudinal studies are required to understand the effect of CFTR modulators on the incidence and natural history of CFLD, including with early treatment initiation, in established advanced liver disease, and post liver transplantation.

Towards a Standardized Classification of the Hepatobiliary Manifestations in Cystic Fibrosis (CFHBI): A Joint ESPGHAN/NASPGHAN Position Paper

The broad spectrum of hepatobiliary involvement in cystic fibrosis (CF) has been commonly referred to as cystic fibrosis liver disease (CFLD). However, differences in the definitions of CFLD have led to variations in reported prevalence, incidence rates, and standardized recommendations for diagnosis and therapies. Harmonizing the description of the spectrum of hepatobiliary involvement in all people with CF (pwCF) is deemed essential for providing a reliable account of the natural history, which in turn supports the development of meaningful clinical outcomes in patient care and research. Recognizing this necessity, The European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) commissioned and tasked a committee to develop and propose a systematic classification of the CF hepatobiliary manifestations to increase uniformity, accuracy, and comparability for clinical, registry, and research purposes. This report describes the committee's combined expert position statement on hepatobiliary involvement in CF, which has been endorsed by NASPGHAN and ESPGHAN. We recommend using CFHBI (Cystic Fibrosis Hepato-Biliary Involvement) as the updated term to describe and classify all hepatobiliary manifestations in all pwCF. CFHBI encompasses the current extensive spectrum of phenotypical, clinical, or diagnostic expressions of liver involvement observed in pwCF. We present a schematic categorization of CFHBI, which may also be used to track and classify the changes and development of CFHBI in pwCF over time. The proposed classification for CFHBI is based on expert consensus and has not been validated for clinical practice and research purposes. Achieving validation should be an important aim for future research.

Improving detection of cystic fibrosis related liver disease using liver fibrosis assessment tools

Background & aims

Cystic Fibrosis related liver disease (CFLD) is the 3rd largest cause of death in Cystic Fibrosis (CF). As advances in pulmonary therapies have increased life-expectancy, CFLD has become more prevalent. Current guidelines may underdiagnose liver fibrosis, particularly in its early stages. Newer modalities for the assessment of fibrosis may provide a more accurate assessment. FibroScan is validated in assessing fibrosis for several aetiologies including alcohol and fatty liver, the CFLD cohort have an entirely different phenotype so the cut off values are not transferrable. We appraised fibrosis assessment tools to improve diagnosis of CFLD.

Methods

A prospective cohort (n = 114) of patients from the Manchester Adult Cystic Fibrosis Centre, UK were identified at annual assessment. Demographic data including co-morbidity, CFTR genotyping, biochemistry and imaging were used alongside current guidelines to group into CFLD and CF without evidence of liver disease. All patients underwent liver stiffness measurement (LSM) and assessment of serum-based fibrosis biomarker panels. A new diagnostic criterion was created and validated in a second, independent cohort.

Results

12 of 114 patient classified as CFLD according to the European Cystic Fibrosis Society best practice guidelines. No specific risk factors for development of CFLD were identified. Liver enzymes were elevated in patients with CFLD. Serum biomarker panels did not improve diagnostic criteria. LSM accurately predicted CFLD. A new diagnostic criterion was proposed and validated in a separate cohort, accurately predicating CFLD in 10 of 32 patients (31 %).

Conclusion

We present a cohort of patients with CF assessed for the presence of liver fibrosis using blood biomarkers and LSM based platforms. We propose a new, simplified diagnostic criteria, capable of accurately predicting liver disease in patients with CF.Clinical trials number: NCT04277819.

Shear wave elastography options in the integrated assessment of liver parenchyma in children

Introduction. Chronic liver diseases in children are accompanied by fibrocirrhotic transformation of the organ. Modern ultrasound diagnostic procedures offer a method that can differentiate between the fibrous and unchanged tissues. The paper includes the results of a study of liver stiffness in healthy children using shear wave elastography. The method presented in the article can come to an active use in the non-invasive detection of fibrosis as part of the integrated assessment of liver in pediatric practice. Aim. To study the stiffness of unchanged liver in children of different gender and age groups.

Materials and methods. Shear wave elastography was performed in 200 healthy children aged 3 to 18 years (103 girls and 97 boys) using Aixplorer apparatus (Supersonic Imagine, France), in three age subgroups: a 3- to 6-year-old group (n = 103), a 7- to 11-year-old group (n = 52), and a 12- to 18-year-old group (n = 45). The measurements were taken in different segments of the right lobe of the liver, in the area free from the vascular structures, fixing the zone of scanning at the depth of 3-5 cm from the capsule. Not less than 10 measurements were made, which enabled to calculate the mean value of liver elasticity.

Results. The study identified the liver stiffness measurement normal range in a group of healthy children. Significant differences in liver stiffness were obtained by comparing the values of 3- to 6- year-old and 7- to 11-year-old groups (P = 0.001); 3- to 6-year-old and 12- to 18-year-old groups (P = 0.001); there were no statistically significant differences in the stiffness values depending on gender (P = 0.345).

Conclusions. Young modulus values obtained may be used as normative. The use of shear wave elastography enhances the accuracy of the conventional ultrasound examination in identifying patients with liver disease.

Comparison of Transient Elastography, ShearWave Elastography, Magnetic Resonance Elastography and FibroTest as routine diagnostic markers for assessing liver fibrosis in children with Cystic Fibrosis

BACKGROUND AND OBJECTIVE

Reliable markers are needed for early diagnosis and follow-up of liver disease in Cystic Fibrosis (CF). The objective was to evaluate the diagnostic performance of Transient Elastography (TE), Real-Time ShearWave Ultrasound Elastography (SWE), Magnetic Resonance Elastography (MRE) and the FibroTest as markers of Cystic Fibrosis Liver Disease (CFLD).

METHODS

A monocentric prospective cross-modality comparison study was proposed to all children (6 to 18 years of age) attending the CF center. Based on liver ultrasound findings, participants were classified into 3 groups: multinodular liver or portal hypertension (Nodular US/PH, advanced CFLD), heterogeneous increased echogenicity (Heterogeneous US, CFLD) or neither (Normal/Homogeneous US, no CFLD). The 4 tests were performed on the same day. The primary outcome was the FibroTest value and liver stiffness measurements (LSM).

RESULTS

55 participants (mean age 12.6 ± 3.3 years; 25 girls) were included between 2015 and 2018: 23 in group Nodular US/PH, 8 in group Heterogeneous US and 24 in group Normal/Homogeneous US (including 4 with steatosis). LSM on TE, SWE and MRE were higher in participants with CFLD (groups Nodular US/PH and Heterogeneous US) compared to others (group Normal/Homogeneous US) (p<0.01), while FibroTest values did not differ (p = 0.09). The optimal cut-off values for predicting CFLD on TE, SWE and MRE were 8.7 (AUC=0.83, Se=0.71, Sp=0.96), 7.8 (AUC=0.85, Se=0.73, Sp=0.96) and 4.15 kPa (AUC=0.68, Se=0.73, Sp=0.64), respectively. LSM predicted the occurrence of major liver-related events at 3 years. TE and SWE were highly correlated (Spearman's ρ=0.9) and concordant in identifying advanced CFLD (Cohen's κ=0.84) while MRE was moderately correlated and concordant with TE (ρ=0.41; κ=36) and SWE (ρ=0.5; κ=0.50).

CONCLUSION

This study demonstrated excellent diagnostic performance of TE, SWE and MRE for the diagnosis of CFLD.

Cystic fibrosis-related liver disease: Clinical presentations, diagnostic and monitoring approaches in the era of CFTR modulator therapies

Cystic fibrosis (CF) is the most common autosomal recessive disease in the Caucasian population. Cystic fibrosis-related liver disease (CFLD) is defined as the pathogenesis related to the underlying CFTR defect in biliary epithelial cells. CFLD needs to be distinguished from other liver manifestations that may not have any pathological significance. The clinical/histological presentation and severity of CFLD vary. The main histological presentation of CFLD is focal biliary fibrosis, which is usually asymptomatic. Portal hypertension develops in a minority of cases (about 10%) and may require specific management including liver transplantation for end-stage liver disease. Portal hypertension is usually the result of the progression of focal biliary fibrosis to multilobular cirrhosis during childhood. Nevertheless, non-cirrhotic portal hypertension as a result of porto-sinusoidal vascular disease is now identified increasingly more frequently, mainly in young adults. To evaluate the effect of new CFTR modulator therapies on the liver, the spectrum of hepatobiliary involvement must first be precisely classified. This paper discusses the phenotypic features of CFLD, its underlying physiopathology and relevant diagnostic and follow-up approaches, with a special focus on imaging.

Association Between Transient Elastography and Controlled Attenuated Parameter and Liver Ultrasound in Children With Cystic Fibrosis

Methods to identify children with cystic fibrosis (CF) at risk for development of advanced liver disease are lacking. We aim to determine the association between liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) with research ultrasound (US) patterns and conventional hepatic markers as a potential means to follow liver disease progression in children with CF. ELASTIC (Longitudinal Assessment of Transient Elastography in CF) is a nested cohort of 141 patients, ages 7-21, enrolled in the Prediction by US of Risk of Hepatic Cirrhosis in CF (PUSH) Study. We studied the association between LSM with research-grade US patterns (normal [NL], heterogeneous [HTG], homogeneous [HMG], or nodular [NOD]) and conventional hepatic markers. In a subgroup (n = 79), the association between controlled attenuation parameter (CAP) and US pattern was explored. Among 133 subjects undergoing VCTE, NOD participants (n = 26) had a significantly higher median (interquartile range) LSM of 9.1 kPa (6.3, 15.8) versus NL (n = 72, 5.1 kPa [4.2, 7.0]; P < 0.0001), HMG (n = 17, 5.9 kPa [5.2, 7.8]; P = 0.0013), and HTG (n = 18, 6.1 kPa [4.7, 7.0]; P = 0.0008) participants. HMG participants (n = 14) had a significantly higher mean CAP (SD) (270.5 dB/m [61.1]) compared with NL (n = 40, 218.8 dB/m [46.5]; P = 0.0027), HTG (n = 10, 218.1 dB/m [60.7]; P = 0.044), and NOD (n = 15, 222.7 dB/m [56.4]; P = 0.041) participants. LSM had a negative correlation with platelet count (r_s =  - 0.28, P = 0.0071) and positive correlation with aspartate aminotransferase-to-platelet ratio index (r_s = 0.38, P = 0.0002), Fibrosis-4 index (r_s = 0.36, P = 0.0007), gamma-glutamyltransferase (GGT; r_s = 0.35, P = 0.0017), GGT-to-platelet ratio (r_s = 0.35, P = 0.003), and US spleen size z-score (r_s = 0.27, P = 0.0073). Conclusion: VCTE is associated with US patterns and conventional markers in patients with liver disease with CF.

Non-invasive Diagnostic Tests in Cystic Fibrosis-Related Liver Disease: A Diagnostic Test Accuracy Network Meta-Analysis

Background and Aims: Cystic fibrosis-related liver disease (CFLD) is one of the leading causes of morbidity and mortality in cystic fibrosis (CF). Several non-invasive diagnostic methods have been proposed as screening tools for CFLD. Our aim was to rank all available non-invasive modalities for diagnostic performance.

Methods: A systematic search was performed in five medical databases to find studies which reported on any single or composite non-invasive diagnostic test (as an index test) compared to the Debray, the EuroCare or the Colombo criteria (as a reference standard). Ranking was carried out with a Bayesian diagnostic test accuracy network meta-analysis based on superiority indices, calculated for pooled sensitivity (Se) and specificity (Sp) with a 95% confidence interval (CI). The study was registered under CRD42020155846 in PROSPERO.

Results: Fifteen studies with 15 index tests and a combination of them were included. The New criteria proposed by Koh et al. – which represent a composite diagnostic definition for CFLD including liver biochemistry, ultrasonography, transient elastography and fibrosis markers—had the best performance for detecting CFLD (Se:94%[CI:58–100], Sp:72%[CI:52–84]); while transient elastography (Se:65%[CI:56–74], Sp:88%[CI:84–91]) and a combination of it with a tissue inhibitor of metalloproteinase-4 measurement (Se:78%[CI:30–100], Sp:64%[CI:18–95%]) proved to be the second and third best options, respectively. In the imaging techniques subgroup, transient elastography (Se:66%[CI:57–72], Sp:88%[CI:85–91%]), acoustic radiation force impulse in the right lobe (Se:54%[CI:33–74], Sp:88%[CI:66–96]) and that in the left lobe (Se:55%[CI:23–81], Sp:82%[CI:50–95]) were ranked the highest. Comparing biochemical markers/fibrosis indices, the measurement of the Forns index (Se:72%[CI:25–99], Sp:63%[CI:16–94]), the aspartate aminotransferase-to-platelet ratio (Se:55%[CI:41–68], Sp:83%[CI:66–89]) and alkaline phosphatase (Se:63%[CI:18–93], Sp:64%[CI:19–95]) were ranked the highest.

Conclusion: The New criteria show the best diagnostic performance. In clinical practice, transient elastography seems to be a simple, cheap and non-invasive tool, outperforming imaging, biochemical and fibrosis tests for detecting CFLD. Further studies are needed to validate our findings.

Clinical use of shear-wave elastography for detecting liver fibrosis in children and adolescents with cystic fibrosis

BACKGROUND

Complications from liver cirrhosis are a leading cause of death in children with cystic fibrosis. Identifying children at risk for developing liver cirrhosis and halting its progression are critical to reducing liver-associated mortality.

OBJECTIVE

Quantitative US imaging, such as shear-wave elastography (SWE), might improve the detection of liver fibrosis in children with cystic fibrosis (CF) over gray-scale US alone. We incorporated SWE in our pediatric CF liver disease screening program and evaluated its performance using magnetic resonance (MR) elastography.

MATERIALS AND METHODS

Ninety-four children and adolescents with CF underwent 178 SWE exams, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT) and platelet measurements. Of these, 27 children underwent 34 MR elastography exams. We evaluated SWE performance using 6-MHz and 9-MHZ point SWE, and 9-MHz two-dimensional (2-D) SWE.

RESULTS

The 6-MHz point SWE was the only method that correlated with MR elastography (r=0.52; 95% confidence interval [CI] 0.20-0.74; P=0.003). SWE of 1.45 m/s distinguished normal from abnormal MR elastography (79% sensitivity, 100% specificity, 100% positive predictive value [PPV], 55% negative predictive value [NPV], area under the receiver operating characteristic [AUROC] curve 0.94). SWE of 1.84 m/s separated mild-moderate (3.00-4.77 kPa) from severe (>4.77 kPa) MR elastography (88% sensitivity, 86% specificity, 78% PPV, 93% NPV, AUROC 0.79). Elevations of AST, ALT, GGT and thrombocytopenia were associated with higher SWE. AST-to-platelet ratio index of 0.42, fibrosis-4 of 0.29, and GGT-to-platelet ratio of 1.43 all had >95% NPV for SWE >1.84 m/s.

CONCLUSION

Given its correlation with MR elastography, SWE might be a clinically useful predictor of liver fibrosis. We identified imaging criteria delineating the use of SWE to identify increased liver stiffness in children with CF. With multicenter validation, these data might be used to improve the detection and monitoring of liver fibrosis in children with CF.

A review of liver dysfunction in the lung transplant patient

Liver dysfunction is an increasingly common finding in patients evaluated for lung transplantation. New or worsening dysfunction in the perioperative period, defined by presence of clinical ascites/encephalopathy, high model for end-stage liver disease (MELD) score, and/or independent diagnostic criteria, is associated with high short- and long-term mortality. Therefore, a thorough liver function assessment is necessary prior to listing for lung transplant. Unfortunately, identification and intraoperative monitoring remain the only options for prevention of disease progression with isolated lung transplantation. Combined lung and liver transplantation may provide an option for definitive long-term management in selecting patients with known liver disease at high risk for postoperative progression. However, experience with the combined operation is extremely limited and indications for combined lung and liver transplant remain unclear. Herein, we present a comprehensive literature review of patients with liver dysfunction undergoing lung transplantation with and without concurrent liver transplant in an effort to illuminate the risks, benefits, and clinical judgement surrounding decision to pursue combined lung-liver transplantation (CLLT). We also argue description of liver function is currently a weakness of the current lung allocation scoring system. Additional algorithms incorporating liver function may aid in risk stratification and decision to pursue combined transplantation.

Role of transient elastography and APRI in the assessment of pediatric cystic fibrosis liver disease

Background

Diagnosis and monitoring of cystic fibrosis liver disease (CFLD) is challenging. Transient elastography (TE) is a rapid, non-invasive method for assessing liver fibrosis. Its role in detecting fibrosis in CFLD has only begun to be explored. The aspartate aminotransferase to platelet ratio index (APRI) has been validated as a predictor of hepatic fibrosis in other chronic liver diseases. The purpose of this study was to assess the utility of APRI and TE in identifying liver fibrosis in pediatric CF patients.

Methods

Patients aged 2-18 years were recruited from the British Columbia Children's Hospital CF clinic. Patients were determined to have CFLD using standard criteria. Charts were reviewed, and each patient underwent TE.

Results

Of the 55 patients included in the study (50.9% male, mean age 11.6 y), 22 (40%) had CFLD. All mean liver enzymes were higher in the CFLD group, notably alanine transaminase (p = 0.031). Mean liver stiffness (LS) and APRI were also higher in the CFLD group (LS: 5.9 versus 4.5 kPa, p = 0.015; APRI: 0.40 versus 0.32, p = 0.119). Linear regression showed a mild positive association between the two (r 2 = 0.386).

Conclusions

TE values were higher among CFLD patients and correlated with APRI values, suggesting that these tools may have clinical applications for identifying and following this population. Further research is needed on a larger scale to determine the relative value and clinical utility of TE and APRI among patients with CFLD.

Extended Screening for Cystic Fibrosis-related Liver Disease Including Elastography in Children and Adolescents

OBJECTIVES

Advances in treatment of cystic fibrosis (CF) have increased survival and thereby prevalence of patients with liver disease, making chronic liver disease one of the major complications of CF. We describe the prevalence of liver fibrosis, portal hypertension, and liver decompensation by extended screening for cystic fibrosis-related liver disease (CFLD) including ultrasound, elastography, and an extended panel of biochemical markers.

METHODS

A cross sectional study of CFLD in all pediatric CF patients (1-18 years) from the Copenhagen CF Center. Screening for liver disease included physical examination, biochemical analysis, Vibration-Controlled Transient Elastography (FibroScan), conventional ultrasound, and Real-Time Shear Wave elastography (SWE). Patients were scored according to Williams ultrasound scoring scale (WUSS) within 6 months.

RESULTS

A total of 84 consecutive patients (male sex 46.4%, median age 10.4 years) were included. Eight patients (9.5%) had both ≥2 abnormal results of sonographic methods and ≥2 abnormal biochemical results and were in this study categorized as having manifest CFLD. Manifest CFLD patients were significantly older and had a higher mean value of APRI, but no differences in gender, z-height, z-weight, z-BMI, FEV1%, or mean value of bilirubin or albumin were found.

CONCLUSIONS

In total, 8 patients (9.5%) in this pediatric CF population were categorized as having CFLD according to both biochemical and sonographic tests. Consistency was found among the results of FibroScan and SWE. We suggest WUSS and either FibroScan or SWE, combined with GGT as diagnostic markers for CFLD.

Can Point Shear Wave Elastography Be Used as an Early Indicator of Involvement?: Evaluation of the Pancreas and Liver in Children With Cystic Fibrosis

OBJECTIVES

The aim of this study was to determine the effect of cystic fibrosis (CF) on pancreas and liver elasticity in young children using point shear wave elastography and to determine the relationship with clinical findings.

METHODS

Twenty-two patients with genetically proven CF, who were admitted to our pediatric gastroenterology clinic, and 22 healthy control participants were enrolled in the study. The shear wave velocity (SWV) of the liver and pancreas were measured with point shear wave elastography.

RESULTS

The 22 patients with CF included 45.5% girls with a mean age ± SD of 35 ± 35.8 months (range, 5-123 months). The 22 healthy control participants included 41.2% girls with a mean age of 58.9 ± 44.4 months (range, 2-159 months). The mean SWV of the pancreas in the patients with CF (1.06 ± 0.26 m/s) was significantly higher than that of the healthy control participants (0.85 ± 0.23 m/s; P = .01). The mean SWV of the liver in the patients with CF (1.46 ± 0.24 m/s) was significantly higher than that of the healthy control participants (1.12 ± 0.21 m/s; P = .001). The SWV of the pancreas and liver did not show any significant differences depending on ursodeoxycholic acid use, malnutrition status, and the presence of the F508 deletion mutation.

CONCLUSIONS

This study showed an increased SWV of the pancreas in children with CF, contrary to the literature. We also found an increased liver SWV even in the absence of CF-related liver disease. Ultrasound elastography may be a useful method of evaluating early changes in the pancreas and liver before the obvious clinical, laboratory, and B-mode ultrasound signs of CF-related involvement.

[18F]-Alfatide PET imaging of integrin αvβ3 for the non-invasive quantification of liver fibrosis

BACKGROUND & AIMS

The vitronectin receptor integrin αvβ3 drives fibrogenic activation of hepatic stellate cells (HSCs). Molecular imaging targeting the integrin αvβ3 could provide a non-invasive method for evaluating the expression and the function of the integrin αvβ3 on activated HSCs (aHSCs) in the injured liver. In this study, we sought to compare differences in the uptake of [18F]-Alfatide between normal and injured liver to evaluate its utility for assessment of hepatic fibrogenesis.

METHODS

PET with [18F]-Alfatide, non-enhanced CT, histopathology, immunofluorescence staining, immunoblotting and gene analysis were performed to evaluate and quantify hepatic integrin αvβ3 levels and liver fibrosis progression in mouse models of fibrosis (carbon tetrachloride [CCl4] and bile duct ligation [BDL]). The liver AUC divided by the blood AUC over 30 min was used as an integrin αvβ3-PET index to quantify fibrosis progression. Ex vivo analysis of frozen liver tissue from patients with fibrosis and cirrhosis verified the animal findings.

RESULTS

Fibrotic mouse livers showed enhanced [18F]-Alfatide uptake and retention compared to control livers. The radiotracer was demonstrated to bind specifically with integrin αvβ3, which is mainly expressed on aHSCs. Autoradiography and histopathology confirmed the PET imaging results. Further, the mRNA and protein level of integrin αvβ3 and its signaling complex were higher in CCl4 and BDL models than controls. The results obtained from analyses on human fibrotic liver sections supported the animal findings.

CONCLUSIONS

Imaging hepatic integrin αvβ3 with PET and [18F]-Alfatide offers a potential non-invasive method for monitoring the progression of liver fibrosis.

LAY SUMMARY

Integrin αvβ3 expression on activated hepatic stellate cells (aHSCs) is associated with HSC proliferation during hepatic fibrogenesis. Herein, we show that a radioactive tracer, [18F]-Alfatide, binds to integrin αvβ3 with high affinity and specificity. [18F]-Alfatide could thus be used as a non-invasive imaging biomarker to track hepatic fibrosis progression.

Accuracy of Transient Elastography Data Combined With APRI in Detection and Staging of Liver Disease in Pediatric Patients With Cystic Fibrosis

BACKGROUND & AIMS

Liver disease develops in 15%-72% of patients with cystic fibrosis, and 5%-10% develop cirrhosis or portal hypertension, usually during childhood. Transient elastography (TE) is a noninvasive method to measure liver stiffness. We aimed to validate its accuracy in detection of liver disease and assessment of fibrosis in children with cystic fibrosis.

METHODS

We performed a cross-sectional study to evaluate the accuracy of TE in analysis of liver disease in 160 consecutive children who presented with cystic fibrosis (9.0 ± 0.4 years old, 53% male) at a tertiary referral pediatric center in Australia, from 2011 through 2016. Patients were classified as having cystic fibrosis-associated liver disease (CFLD) or cystic fibrosis without liver disease (CFnoLD) based on clinical, biochemical, and imaging features. Fibrosis severity was determined from histologic analysis of dual-pass liver biopsies from children with CFLD, as the reference standard. Data from healthy children without cystic fibrosis (n = 64, controls) were obtained from a separate study. Liver stiffness measurements (LSMs) were made by Fibroscan analysis, using the inter-quartile range/median ≤30% of 10 valid measurements. Children with macronodularity or portal hypertension with heterogeneous changes on ultrasound without available biopsy were assigned to the category of stage F3-F4 fibrosis.

RESULTS

LSM was made reliably in 86% of children; accuracy increased with age. LSMs were significantly higher in children with CFLD (10.7 ± 2.4 kPa, n = 33) than with CFnoLD (4.6 ± 0.1 kPa, n = 105) (P < .0001) or controls (4.1 ± 0.1kPa) (P < .0001); LSMs were higher in children with CFnoLD than controls (P < .05). At a cut-off value of 5.55kPa, LSM identified children with CFLD with an area under the receiver operating characteristic (AUROC) curve of 0.82, 70% sensitivity, and 82% specificity (P < .0001). Classification and regression tree models that combined LSM and aspartate aminotransferase to platelet ratio index (APRI) identified children with CFLD with an AUROC curve of 0.89, 87% sensitivity, and 74% specificity (odds ratio, 18.6). LSMs correlated with fibrosis stage in patients with CFLD (r = 0.67, P = .0001). A cut-off value of 8.7kPa differentiated patients with stage F3-F4 fibrosis from patients with stage F1-F2 fibrosis (AUROC, 0.87; 75% sensitivity; 100% specificity, P=.0002). The combination of LSMs and APRI improved the differentiation of patients with F3-F4 fibrosis vs F1-F2 fibrosis (AUROC, 0.92; 83% sensitivity; and 100% specificity (P < .01).

CONCLUSIONS

LSMs made by TE accurately detect liver disease in children with cystic fibrosis; diagnostic accuracy increases when LSMs are combined with APRI. LSMs also differentiate between children with cystic fibrosis with mild-moderate fibrosis vs advanced fibrosis.

Liver Ultrasound Patterns in Children With Cystic Fibrosis Correlate With Noninvasive Tests of Liver Disease

OBJECTIVES

Early identification of children with cystic fibrosis (CF) at risk for severe liver disease (CFLD) would enable targeted study of preventative therapies. There is no gold standard test for CFLD. Ultrasonography (US) is used to identify CFLD, but with concerns for its diagnostic accuracy. We aim to determine if differences in standard blood tests, imaging variables and noninvasive liver fibrosis indices correlate with liver US patterns, and thus provide supportive evidence that a heterogeneous US liver pattern reflects clinically relevant liver disease.

METHODS

We studied baseline research abdominal US and bloodwork from 244 children with pancreatic insufficient CF, ages 3 to 12 years, enrolled in a prospective study of the ability of US to predict CF cirrhosis (PUSH study). Children with a heterogeneous (HTG) liver pattern on US (n = 62) were matched 1 : 2 in design with children with normal US (NL, n = 122). Analyses included children with nodular (NOD, n = 22) and homogeneous hyperechoic (HMG, n = 38) livers.

RESULTS

Univariate analysis showed significant differences between US groups for standard blood tests, spleen size, and noninvasive liver fibrosis indices. Multivariable models discriminated NOD versus NL with excellent accuracy (AUROC 0.96). Models also distinguish HTG versus NL (AUROC 0.76), NOD versus HTG (0.78), and HMG versus NL (0.79).

CONCLUSIONS

Liver US patterns in children with CF correlate with platelet count, spleen size and indices of liver fibrosis. Multivariable models of these biomarkers have excellent discriminating ability for NL versus NOD, and good ability to distinguish other US patterns, suggesting that US patterns correlate with clinically relevant liver disease.

Cystic fibrosis liver disease: A condition in need of structured transition and continuity of care

Liver disease affects one-third of patients with cystic fibrosis (CF) and it is one of the major causes of morbidity and mortality in these patients. Historically considered a disease of childhood, its impact is now seen more often in adulthood. The heterogeneous pattern of CF liver disease and its rapid progression to cirrhosis remain a diagnostic challenge and new questions pertaining to the nature of liver involvement have recently been raised. Non-invasive measures to stratify the severity of liver involvement are increasingly used to predict clinical outcomes. A single treatment, ursodeoxycholic acid, has been used to slow progression of liver disease while recent advances in the field of CF treatments are promising. Management of portal hypertension remains challenging but outcomes after liver transplantation are encouraging. While many questions remain unanswered, a growing number of CF patients reach adulthood and will require care for CF liver disease.

Evaluation of liver tissue by ultrasound elastography and clinical parameters in children with multiple blood cell transfusions

BACKGROUND

Children receiving multiple blood cell transfusions are prone to iron overload and successive tissue damage in liver parenchyma, making noninvasive screening options desirable. Ultrasound (US) elastography using acoustic radiation force impulse (ARFI) imaging enables evaluation of liver parenchyma stiffness, and MRI allows for quantification of liver iron concentration.

OBJECTIVE

The objective was to correlate US elastography with MRI in children who had undergone bone marrow transplantation and to evaluate the modification of liver tissue with US in combination with clinical parameters at follow-up.

MATERIALS AND METHODS

ARFI, T2*-weighted MRI and a clinical score (HepScore, based on parameters of liver function) were performed in 45 patients (24 male; mean age 9.7 years) before and 100 days and 365 days after transplantation. All received multiple blood transfusions (mean number 22.2 up until 1 year after transplantation). We correlated US findings and HepScore with MRI findings.

RESULTS

We observed signs of iron accumulation in 29/45 (64.4%) patients on MRI (T2*<10 ms) and 15/45 (33.3%) showed increased tissue stiffness (ARFI>5.5 kPa). Correlation of elastography and MRI was not significant (P=0.57; n=51 matched measurements). Comparing US elastography with HepScore in receiver operating characteristic (ROC) curve analysis indicated a cut-off for affected parenchyma if HepScore was >5 points (sensitivity 67%, specificity 68%). Simultaneous increases of both indicated tissue alteration.

CONCLUSION

Combining US and HepScore enabled detection of liver tissue alteration through iron overload, but we found no direct significant effect of estimated iron from MRI on ARFI imaging.

Practical approach to the gastrointestinal manifestations of cystic fibrosis

Cystic fibrosis (CF) is the most common, life-shortening, genetic illness affecting children in Australia and New Zealand. The genetic abnormality results in abnormal anion transport across the apical membrane of epithelial cells in a number of organs, including the lungs, gastrointestinal tract, liver and genito-urinary tract. Thus, CF is a multi-system disorder that requires a multi-disciplinary approach. Respiratory disease is the predominant cause of both morbidity and mortality in patients with CF. However, there are significant and clinically relevant gastrointestinal, liver, pancreatic and nutritional manifestations that must be detected and managed in a timely and structured manner. The aim of this review is to provide evidence-based information and clinical algorithms to guide the nutritional and gastrointestinal management of patients with CF.

Assessment of liver disease in cystic fibrosis

Liver disease in cystic fibrosis has many causes, with biliary fibrosis due to abnormal CFTR protein predominating. Assessment requires aetiology to be defined. Biliary fibrosis may progress to cirrhosis and portal hypertension, which although initially asymptomatic, may cause varices and splenomegaly. Monitoring progression includes clinical and ultrasound assessment with endoscopic assessment of varices for those at risk. Extrapolated primarily from longitudinal assessment of viral hepatitis in adults, non-invasive elastography has a potential role. Evidence is lacking to support intervention strategies, but ursodeoxycholic acid and ligation of varices are widely applied. Indication and timing of liver transplantation are not clearly defined. Multidisciplinary approach is needed to tailor assessment and guide management.

Assessment of Liver Disease Progression in Cystic Fibrosis Using Transient Elastography

OBJECTIVES

Cystic fibrosis-related liver disease (CFLD) can develop silently in early life and approximately 10% of children with cystic fibrosis (CF) become cirrhotic before adulthood. Clinical, biological, and ultrasound criteria used to define CFLD often reveal liver involvement at an advanced stage. The aim of this retrospective study was to assess the progression of liver stiffness measurement (LSM) in pediatric patients with CF.

METHODS

The change of LSM, expressed as kPa/year and %/year, was measured using transient elastography (Fibroscan) in 82 children with CF (median age: 6.8 years, interquartile range [IQR]: 5.8). Mean time interval between the 2 LSM was 3.5 years.

RESULTS

Median initial liver stiffness was 3.7 kPa (IQR: 1.3), and then progressed by 0.23 kPa/year, that is, 6%/year. The 7 patients who developed CFLD had a higher initial level of alanine aminotransferase (50 [IQR: 15] vs 30 [IQR: 18], P = 0.0001) and presented a more rapid progression of LSM (0.94 vs 0.23 kPa/year, P = 0.02).

CONCLUSIONS

The present study shows that the slope of worsening of liver stiffness is greater in patients who will develop CFLD, suggesting that annual transient elastography may be useful to detect risk of severe liver disease at an earlier stage.

Cystic Fibrosis-related Liver Disease: Research Challenges and Future Perspectives

OBJECTIVES

Hepatobiliary complications are a leading cause of morbidity and mortality in cystic fibrosis (CF) patients. Knowledge of the underlying pathological aspects and optimal clinical management is, however, sorely lacking.

METHODS

We provide a summary of the lectures given by international speakers at the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) monothematic conference on cystic fibrosis-related liver disease (CFLD) held in Paris in January 2016, to discuss the status of our current knowledge of liver disease in CF patients, to define the critical areas that need to be addressed, and to resolve actions to elucidate relevant mechanisms of disease to optimise future therapeutic options.

CONCLUSIONS

The need for a universal consensus on the definition of CFLD to clarify disease stage and to identify relevant biomarkers to assess disease severity was highlighted. A deeper understanding of the pathophysiology and prognostic factors for the long-term evolution of CFLD is fundamental to move forward and has a strong bearing on identifying potential treatments. Novel experimental models and new treatment options under investigation are discussed and offer hope for the near future of CFLD.

Imaging the Abdominal Manifestations of Cystic Fibrosis

Cystic fibrosis (CF) is a multisystem disease with a range of abdominal manifestations including those involving the liver, pancreas, and kidneys. Recent advances in management of the respiratory complications of the disease has led to a greater life expectancy in patients with CF. Subsequently, there is increasing focus on the impact of abdominal disease on quality of life and survival. Liver cirrhosis is the most important extrapulmonary cause of death in CF, yet significant challenges remain in the diagnosis of CF related liver disease. The capacity to predict those patients at risk of developing cirrhosis remains a significant challenge. We review representative abdominal imaging findings in patients with CF selected from the records of two academic health centres, with a view to increasing familiarity with the abdominal manifestations of the disease. We review their presentation and expected imaging findings, with a focus on the challenges facing diagnosis of the hepatic manifestations of the disease. An increased familiarity with these abdominal manifestations will facilitate timely diagnosis and management, which is paramount to further improving outcomes for patients with cystic fibrosis.

Longitudinal Transient Elastography Measurements Used in Follow-up for Patients with Cystic Fibrosis

Cystic fibrosis-related liver disease (CFLD) is diagnosed using a combination of criteria. Transient elastography (TE), an ultrasonographic method to evaluate liver stiffness, can differentiate patients with and without liver disease. This retrospective study (2007-2013) aimed to detect developing CFLD using consequent TE measurements. All cystic fibrosis patients with TE measurements between 2007 and 2013 (n = 150, median age 17 (9-24) y) were included, of which 118 had a median of three (range, 2-4) measurements with an interval of 1 (1-2) y. Twenty (14%) had CFLD at the first TE measurement; five (3%) developed CFLD during follow-up. The median TE value in CFLD was 14 kPa (8.7-32.2) compared with 5.3 (4.9-5.7) in cystic fibrosis patients without liver disease (CFnoLD; p = 0.0001). In CFnoLD, TE was correlated with age (p = 0.031). A TE result >6.8 kPa had a sensitivity of 91.5% and a specificity of 91.7% in predicting CFLD, according to the receiver operating characteristics analysis. It also has a positive predictive value of 88.6% and a negative predictive value of 86.9%, increasing to 91.7% and 98%, respectively, in patients at risk (<14 y) for developing CFLD. Patients with developing CFLD had progressively increasing consecutive TE measurements.

(13) C Breath Tests Are Feasible in Patients With Extracorporeal Membrane Oxygenation Devices

Temporary extracorporeal membrane oxygenation (ECMO) has been established as an essential part of therapy in patients with pulmonary or cardiac failure. As physiological gaseous exchange is artificially altered in this patient group, it is debatable whether a (13) C-breath test can be carried out. In this proof of technical feasibility report, we assess the viability of the (13) C-breath test LiMAx (maximum liver function capacity) in patients on ECMO therapy. All breath probes for the test device were obtained directly via the membrane oxygenator. Data of four patients receiving liver function assessment with the (13) C-breath test LiMAx while having ECMO therapy were analyzed. All results were compared with validated scenarios of the testing procedures. The LiMAx test could successfully be carried out in every case without changing ECMO settings. Clinical course of the patients ranging from multiorgan failure to no sign of liver insufficiency was in accordance with the results of the LiMAx liver function test. The (13) C-breath test is technically feasible in the context of ECMO. Further evaluation of (13) C-breath test in general would be worthwhile. The LiMAx test as a (13) C-breath test accessing liver function might be of particular predictive interest if patients with ECMO therapy develop multiorgan failure.

Aspartate aminotransferase to platelet ratio and fibrosis-4 as biomarkers in biopsy-validated pediatric cystic fibrosis liver disease

Up to 10% of cystic fibrosis (CF) children develop cirrhosis by the first decade. We evaluated the utility of two simple biomarkers, aspartate aminotransferase to platelet ratio index (APRI) and FIB-4, in predicting degree of fibrosis in pediatric CF liver disease (CFLD) validated by liver biopsy. In this retrospective, cross-sectional study, 67 children with CFLD had dual-pass liver biopsies and 104 age- and sex-matched CF children without liver disease (CFnoLD) had serum to calculate APRI and FIB-4 collected at enrollment. CFLD was defined as having two of the following: (1) hepatomegaly±splenomegaly; (2)>6 months elevation of ALT (>1.5× upper limit of normal ULN); or (3) abnormal liver ultrasound findings. Biopsies were staged according to Metavir classification by two blinded pathologists. Receiver operating characteristic (ROC) analysis and continuation ratio logistic regression were performed to assess the predictability of these biomarkers to distinguish CFLD from CFnoLD and determine fibrosis stage-specific cut-off values. The AUC for APRI was better than FIB-4 (0.75 vs. 0.60; P=0.005) for predicting CFLD and severe CFLD (F3-F4) (0.81). An APRI score>0.264 demonstrated a sensitivity (95% confidence interval [CI]) of 73.1% (60.9, 83.2) and specificity of 70.2% (60.4, 78.8) in predicting CFLD. A 50% increase in APRI was associated with a 2.4-fold (95% CI: 1.7, 3.3) increased odds of having CFLD. APRI demonstrated full agreement with histology staging 37% of the time, but was within one stage 73% of the time. Only FIB-4 predicted portal hypertension at diagnosis (area under the receiver operator characteristic curve [AUC 0.91; P<0.001).

CONCLUSION

This is the first liver biopsy-validated study of APRI and FIB-4 in pediatric CFLD. APRI appears superior to FIB-4 in differentiating CFLD versus CFnoLD. APRI also exhibited a high AUC in predicting severe liver fibrosis with specific cutoffs for lower stages.

Increase of Serum γ-Glutamyltransferase Associated With Development of Cirrhotic Cystic Fibrosis Liver Disease

BACKGROUND

Identification of patients at risk for developing cirrhotic cystic fibrosis liver disease (CCFLD) is essential for targeting potentially preventive treatment. We studied the evolution of serum liver enzymes and thrombocyte counts as predictors of CCFLD development.

METHODS

For this study, we defined the diagnosis of CCFLD as the combination of splenomegaly (on either physical examination or ultrasound scan) and macronodularity of the liver on ultrasound scan. We reviewed the medical records of 277 pediatric patients with CF for the diagnosis of CCFLD. In each patient with CCFLD, we reviewed serum liver enzymes and thrombocyte counts in the 2-year period preceding the diagnosis of CCFLD. We compared these results with a non-CCFLD control group (patients with CF older than 15 years with no reported signs or symptoms of CCFLD).

RESULTS

In the 2 years preceding the diagnosis, the γ-glutamyltranspeptidase (GGT) levels of patients with CCFLD were significantly higher compared to non-CCFLD controls (42 ± 5 vs 17 ± 2 U/L, respectively; P < 0.001). Corresponding aspartate aminotransferase and alanine aminotransferase levels did not significantly differ between patients with CCFLD and controls. The thrombocyte counts in patients with CCFLD were significantly lower than those in controls (252 ± 108 vs 320 ± 94 × 10 /L, respectively; P < 0.05). The predictive value for CCFLD of a single GGT measurement was low; however, for patients with CF with a mean GGT > 35 U/L, based on repeated measurements, the odds ratio for developing CCFLD was 39 (95% confidence interval 9-175, specificity was 95%, sensitivity was 64%, positive predictive value was 50%). For the thrombocytes, however, no reliable cutoff value could be identified.

CONCLUSIONS

In pediatric patients with CF, a persistently high-normal GGT is strongly associated with the diagnosis of CCFLD within 2 years. The prognostic value of a single GGT measurement is limited, but repeated GGT measurements may allow the identification of groups of patients at increased risk for CCFLD.

Cystic fibrosis: an update for clinicians. Part 2: hepatobiliary and pancreatic manifestations

This paper, the second in the series, will build on the first and explore the importance of liver and pancreatic manifestations of cystic fibrosis (CF) and the effect on morbidity and mortality of this multifaceted genetic condition. It will also further develop the critical role of the gastroenterologist as part of the multidisciplinary group of clinicians and allied health staff in the effective management of patients with CF.

Cystic fibrosis related liver disease--another black box in hepatology

Due to improved medical care, life expectancy in patients with cystic fibrosis (CF) has veritably improved over the last decades. Importantly, cystic fibrosis related liver disease (CFLD) has become one of the leading causes of morbidity and mortality in CF patients. However, CFLD might be largely underdiagnosed and diagnostic criteria need to be refined. The underlying pathomechanisms are largely unknown, and treatment strategies with proven efficacy are lacking. This review focuses on current invasive and non-invasive diagnostic standards, the current knowledge on the pathophysiology of CFLD, treatment strategies, and possible future developments.

Paediatric ultrasonography of the liver, hepatobiliary tract and pancreas

In the field of paediatric radiology ultrasonography (US) is the most versatile imaging tool available. Children in general, by virtue of their body composition, are excellent candidates for US exams in whom abdominal anatomy and pathology can be visualised in great detail. The fact that during the US study a clinical history can be obtained strongly adds to the value of the US exam. This does require investment in time and expertise and ideally a paediatric radiologist performing the exam. In this review the role of ultrasonography (US) of the liver, biliary tract and pancreas in children is discussed.

Liver disease in cystic fibrosis

The survival of patients with cystic fibrosis (CF) has progressively increased over recent decades, largely attributable to early diagnosis through newborn screening and advances in nutritional and respiratory care. As the life expectancy of patients with CF has improved, non-respiratory complications such as liver disease have become increasingly recognized. Biochemical derangements of liver enzymes in CF are common and may be attributed to a number of specific hepatobiliary abnormalities. Among them, Cystic Fibrosis-associated Liver Disease (CFLD) is clinically the most significant hepatic complication and is believed to have a significant impact on morbidity and mortality. However, there remains much conjecture about the extent of the adverse prognostic implications that a diagnosis of CFLD has on clinical outcomes. The purpose of this review is to give an overview of the current knowledge regarding liver disease in children with CF.

Liver disease in cystic fibrosis: an update

CONTEXT

Cystic fibrosis (CF) is the most widespread autosomal recessive genetic disorder that limits life expectation amongst the Caucasian population. As the median survival has increased related to early multidisciplinary intervention, other manifestations of CF have emerged especially for the broad spectrum of hepatobiliary involvement. The present study reviews the existing literature on liver disease in cystic fibrosis and describes the key issues for an adequate clinical evaluation and management of patients, with a focus on the pathogenetic, clinical and diagnostic-therapeutic aspects of liver disease in CF.

EVIDENCE ACQUISITION

A literature search of electronic databases was undertaken for relevant studies published from 1990 about liver disease in cystic fibrosis. The databases searched were: EMBASE, PubMed and Cochrane Library.

RESULTS

CF is due to mutations in the gene on chromosome 7 that encodes an amino acidic polypeptide named CFTR (cystic fibrosis transmembrane regulator). The hepatic manifestations include particular changes referring to the basic CFTR defect, iatrogenic lesions or consequences of the multisystem disease. Even though hepatobiliary disease is the most common non-pulmonary cause of mortality in CF (the third after pulmonary disease and transplant complications), only about the 33%of CF patients presents clinically significant hepatobiliary disease.

CONCLUSIONS

Liver disease will have a growing impact on survival and quality of life of cystic fibrosis patients because a longer life expectancy and for this it is important its early recognition and a correct clinical management aimed at delaying the onset of complications. This review could represent an opportunity to encourage researchers to better investigate genotype-phenotype correlation associated with the development of cystic fibrosis liver disease, especially for non-CFTR genetic polymorphisms, and detect predisposed individuals. Therapeutic trials are needed to find strategies of fibrosis prevention and to avoid its progression prior to development its related complications.

A pilot study of the characterization of hepatic tissue strain in children with cystic-fibrosis-associated liver disease (CFLD) by acoustic radiation force impulse imaging

BACKGROUND

Progressive fibrotic alterations of liver tissue represent a major complication in children with cystic fibrosis. Correct assessment of cystic-fibrosis-associated liver disease (CFLD) in clinical routine is a challenging issue. Sonographic elastography based on acoustic radiation force impulse imaging (ARFI) is a new noninvasive approach for quantitatively assessing in vivo elasticity of biological tissues in many organs.

OBJECTIVE

To characterize ARFI elastography as a diagnostic tool to assess alteration of liver tissue elasticity related to cystic fibrosis in children.

MATERIALS AND METHODS

ARFI elastography and B-mode US imaging were performed in 36 children with cystic fibrosis. The children's clinical history and laboratory parameters were documented. According to the findings on conventional US, children were assigned to distinct groups indicating severity of hepatic tissue alterations. The relationship between US findings and respective elastography values was assessed. Additionally, differences between ARFI elastography values of each US group were statistically tested.

RESULTS

Children with sonomorphologic characteristics of fibrotic tissue remodeling presented significantly increased values for tissue elasticity. Children with normal B-mode US or discrete signs of hepatic tissue alterations showed a tendency toward increased tissue stiffness indicating early tissue remodeling.

CONCLUSION

Assessment of children with CFLD by means of ARFI elastography yields adequate results when compared to conventional US. For detection of early stages of liver disease with mild fibrotic reactions of hepatic tissue, ARFI elastography might offer diagnostic advantages over conventional US. Thus, liver stiffness measured by means of elastography might represent a valuable biological parameter for evaluation and follow-up of CFLD.

Acoustic radiation force impulse (ARFI) imaging with Virtual Touch Tissue Quantification in liver disease associated with cystic fibrosis in children

PURPOSE

Cystic-fibrosis-associated liver disease (CFLD) may lead to portal hypertension (PHT) and cirrhosis. Clinical signs and biochemistry of liver involvement are not discriminating. The aim of the study was to evaluate the performance of acoustic radiation force impulse (ARFI) with virtual tissue quantification in comparison with clinical signs, biochemistry and standard hepatic ultrasound (US) patterns.

MATERIALS AND METHODS

Virtual Touch Tissue Quantification, an implementation of US ARFI with shear-wave velocity (SWV) measurements was used in 75 children with cystic fibrosis (CF) and suspected CFLD to quantify hepatic stiffness. In each patient, ten measurements of SWV were performed on the right hepatic lobe. Patients were also evaluated by standard diagnostic tools (standard US, liver- and lung function tests, oesophagogastroscopy).

RESULTS

Among CF patients, median SWV was significantly higher in patients with clinical, biochemical and US signs of hepatic involvement than in patients without US evidence of liver disease 1.08 m/s [(95% confidence interval (CI), 1.02-1.14]. Median SWV values in patients with portal hypertension, splenomegaly and oesophageal varices were 1.30 (95% CI, 1.17-1.43), 1.54 (95% CI, 1.32-1.75) and 1.63 (95% CI, 1.26-1.99), respectively. Differences were significant (p<0.001).

CONCLUSIONS

ARFI is an innovative screening technique able to help identify CFLD in children.

TIMP-1/-2 and transient elastography allow non invasive diagnosis of cystic fibrosis associated liver disease

BACKGROUND

Cystic fibrosis (CF) associated liver disease develops in approximately 30% of CF patients. However, routine sensitive diagnostic tools are lacking.

AIMS

We aimed to compare the value of transient elastography and experimental fibrosis markers for the detection of liver disease in CF patients.

METHODS

145 CF patients (75 children, 70 adults) were prospectively studied and received transient elastography. CF liver disease was diagnosed according to recent guidelines. Serum concentrations of YKL-40, HA, PIIIP, MMP-9, TIMP-1 and TIMP-2 were determined by ELISA.

RESULTS

Transient elastography was increased in adults and children with CF hepatopathy compared to those without and exhibited a high diagnostic accuracy for CF liver disease. In adults with portal hypertension, elastography was further enhanced. TIMP-2 was elevated in adults with CF hepatopathy associated portal hypertension and exhibited a high diagnostic accuracy for portal hypertension in adults and for CF hepatopathy in children. TIMP-1 had a high diagnostic accuracy for CF hepatopathy in adults. Diagnostic sensitivities were increased when elastography and respective biomarkers were combined for the detection of CF hepatopathy and portal hypertension.

CONCLUSIONS

TIMP-1 and TIMP-2 represent powerful biomarkers for CF associated liver disease and portal hypertension. Their determination may confirm and improve the diagnostic accuracy of transient elastography.

Non-invasive evaluation of cystic fibrosis related liver disease in adults with ARFI, transient elastography and different fibrosis scores

Background

Cystic fibrosis-related liver disease (CFLD) is present in up to 30% of cystic fibrosis patients and can result in progressive liver failure. Diagnosis of CFLD is challenging. Non-invasive methods for staging of liver fibrosis display an interesting diagnostic approach for CFLD detection.

Aim

We evaluated transient elastography (TE), acoustic radiation force impulse imaging (ARFI), and fibrosis indices for CFLD detection.

Methods

TE and ARFI were performed in 55 adult CF patients. In addition, AST/Platelets-Ratio-Index (APRI), and Forns' score were calculated. Healthy probands and patients with alcoholic liver cirrhosis served as controls.

Results

Fourteen CF patients met CFLD criteria, six had liver cirrhosis. Elastography acquisition was successful in >89% of cases. Non-cirrhotic CFLD individuals showed elastography values similar to CF patients without liver involvement. Cases with liver cirrhosis differed significantly from other CFLD patients (ARFI: 1.49 vs. 1.13 m/s; p = 0.031; TE: 7.95 vs. 4.16 kPa; p = 0.020) and had significantly lower results than individuals with alcoholic liver cirrhosis (ARFI: 1.49 vs. 2.99 m/s; p = 0.002). APRI showed the best diagnostic performance for CFLD detection (AUROC 0.815; sensitivity 85.7%, specificity 70.7%).

Conclusions

ARFI, TE, and laboratory based fibrosis indices correlate with each other and reliably detect CFLD related liver cirrhosis in adult CF patients. CF specific cut-off values for cirrhosis in adults are lower than in alcoholic cirrhosis.

Liver disease in cystic fibrosis

PURPOSE OF REVIEW

This review looks at what is currently known about liver disease in cystic fibrosis (CF) in light of the literature over the past year, and what the ongoing challenges are from a clinical and research perspective for the optimal management of cystic fibrosis liver disease (CFLD).

RECENT FINDINGS

Patients with CF who develop clinically significant liver disease have a worse overall phenotype, and whereas there is no definite evidence that they have a shorter life expectancy, longer follow-up is required to determine if liver disease is a risk factor for mortality in CF.The development of the ferret and pig animal models of CF with multiorgan involvement is an important breakthrough which will enhance our understanding of the pathogenesis of CFLD, and with which it is hoped novel therapeutic targets for the treatment of CFLD will be identified.

SUMMARY

Whereas there is still no effective treatment for liver disease in CF, recent developments of animal models of CFLD will enhance our capacity to develop new therapeutic targets and reduce the impact of liver disease on mortality in CF.

Best practice guidance for the diagnosis and management of cystic fibrosis-associated liver disease

Approximately 5-10% of cystic fibrosis (CF) patients develop multilobular cirrhosis during the first decade of life. Most CF patients later develop signs of portal hypertension with complications, mainly variceal bleeding. Liver failure usually occurs later, after the paediatric age. Annual screening for liver disease is recommended to detect pre-symptomatic signs and initiate ursodeoxycholic acid therapy, which might halt disease progression. Liver disease should be considered if at least two of the following variables are present: abnormal physical examination, persistently abnormal liver function tests and pathological ultrasonography. If there is diagnostic doubt, a liver biopsy is indicated. All CF patients with liver disease need annual follow-up to evaluate the development of cirrhosis, portal hypertension or liver failure. Management should focus on nutrition, prevention of bleeding and variceal decompression. Deterioration of pulmonary function is an important consideration for liver transplantation, particularly in children with hepatic dysfunction or advanced portal hypertension.

Hepatobiliary and pancreatic imaging in children-techniques and an overview of non-neoplastic disease entities

Imaging plays a major role in the diagnostic work-up of children with hepatobiliary or pancreatic diseases. It consists mainly of US, CT and MRI, with US and MRI being the preferred imaging modalities because of the lack of ionizing radiation. In this review the technique of US, CT and MRI in children will be addressed, followed by a comprehensive overview of the imaging characteristics of several hepatobiliary and pancreatic disease entities most common in the paediatric age group.

Outcome in cystic fibrosis liver disease

OBJECTIVES

Evidence suggests that cystic fibrosis liver disease (CFLD) does not affect mortality or morbidity in patients with cystic fibrosis (CF). The importance of gender and age in outcome in CF makes selection of an appropriate comparison group central to the interpretation of any differences in mortality and morbidity in patients with CFLD.

METHODS

This is a 7-year follow-up of 42 children with CFLD and their age- and sex-matched controls. Participants were reviewed clinically, biochemically, and radiologically at follow-up.

RESULTS

Overall, 85% (72 of 84) of the original cohort were included, 36 CFLD participants and 36 CF controls. There was no significant difference in the number of deaths/transplants between groups (7 of 36 (19.4%) CFLD participants, 3 of 36 (8.3%) CF controls). There was a tendency for participants with CFLD to die younger than their respective CF controls. There was no difference in height, weight, body mass index, or pulmonary function between the groups. Nutritional parameters (sum skinfold thickness 31.6 vs. 42.3, P=0.03; mean upper arm fat area 15.08 vs. 10.59, P=0.001; Shwachman score 43.7 vs. 32.1, P=0.001) were worse among CFLD participants than among CF controls. Cystic fibrosis-related diabetes was more common in CFLD participants (11 of 27 (40.7%) vs. 5 of 33 (15.2%), P=0.02). Eight children (22.2%) with evidence of CFLD at baseline had no clinical evidence of liver disease as adults.

CONCLUSIONS

Patients with CFLD have a more severe CF phenotype than do CF patients without liver disease. However, a subgroup of children with CFLD will not manifest clinically significant liver disease as adults.

Importance of hepatic fibrosis in cystic fibrosis and the predictive value of liver biopsy

Cystic fibrosis liver disease (CFLD), which results from progressive hepatobiliary fibrosis, is an important cause of morbidity and mortality, but it is difficult to identify before portal hypertension (PHT) ensues. Clinical signs, serum alanine aminotransferase (ALT) levels, and ultrasound (US) are widely applied, but their value in predicting the presence of cirrhosis, the development of PHT, or adverse outcomes is undetermined. The potential gold standard, liver biopsy, is not standard practice and, notwithstanding sampling error considerations, has not been systematically evaluated. Forty patients with cystic fibrosis (median age = 10.6 years) with abnormal clinical, biochemical, and US findings were subjected to dual-pass percutaneous liver biopsy. Clinical outcomes were recorded over 12 years of follow-up (median = 9.5 years for survivors). Logistic regression and receiver operating characteristic analyses were applied to predict hepatic fibrosis (which was assessed by fibrosis staging and quantitative immunohistochemistry) and the occurrence of PHT. PHT occurred in 17 of 40 patients (42%), including 6 of 7 (17%) who died during follow-up. Clinical examination, serum ALT levels, and US findings failed to predict either the presence of liver fibrosis or the development of PHT. Fibrosis staging on liver biopsy, where the accuracy was improved by dual passes (P = 0.002, nonconcordance = 38%), predicted the development of PHT (P < 0.001), which occurred more frequently and at a younger age in those with severe fibrosis.

CONCLUSION

Clinical modalities currently employed to evaluate suspected CFLD help to identify a cohort of children at risk for liver disease and adverse outcomes but do not predict an individual's risk of liver fibrosis or PHT development. Liver fibrosis on biopsy predicts the development of clinically significant liver disease. Dual passes help to address sampling concerns. Liver biopsy has a relevant role in the management of patients with suspected CFLD and deserves more widespread application.