Correlation of Transient Elastography With Severity of Cystic Fibrosis-related Liver Disease

Assessment of cystic fibrosis related liver disease in a pediatric cohort

BACKGROUND

Cystic fibrosis (CF) is an autosomal recessive, chronic, potentially lethal genetic disease. CF manifestations are due to mutations in the CF transmembrane receptor transporter (CFTR) gene which codes for a protein (CFTR) that acts as an anion transporter, mainly chlorine, at epithelial cells where it is expressed. Cystic fibrosis related liver disease (CFRLD) includes a spectrum of hepatobiliary manifestations whose diagnosis and follow-up remains a challenge.

METHODS

Cross-sectional, descriptive study from 10 Spanish cystic fibrosis units. Clinical and biochemical data obtained. Patients categorized into 3 groups according to liver involvement based on ESPGHAN 2017 criteria. Liver stiffness assessed by transient elastography (TE) and findings from abdominal ultrasound recorded. Statistics performed using SPSS v25.0.

RESULTS

We obtained hepatic TE data from 155 pediatric CF patients. Forty-four classified as CFRLD, 38 (86%) had CFRLD without cirrhosis and 6 (14%) had cirrhosis. Fourteen patients without CFRLD (12%) had ultrasound abnormalities. Mean liver elastography value (kPa) was 4.7 (3.5-5.3) in non-CFRLD and 6.09 (4.4-6.7) in CFRLD (p=0.01; T Student [T]).

CONCLUSIONS

CFRLD is common in children with CF. Transient elastography is a useful method for diagnosis and follow-up, as higher values of TE are found in patients with CFRLD.

WFUMB Guideline/Guidance on Liver Multiparametric Ultrasound: Part 1. Update to 2018 Guidelines on Liver Ultrasound Elastography

The World Federation for Ultrasound in Medicine and Biology (WFUMB) endorsed the development of this document on multiparametric ultrasound. Part 1 is an update to the WFUMB Liver Elastography Guidelines Update released in 2018 and provides new evidence on the role of ultrasound elastography in chronic liver disease. The recommendations in this update were made and graded using the Oxford classification, including level of evidence (LoE), grade of recommendation (GoR) and proportion of agreement (Oxford Centre for Evidence-Based Medicine [OCEBM] 2009). The guidelines are clinically oriented, and the role of shear wave elastography in both fibrosis staging and prognostication in different etiologies of liver disease is discussed, highlighting advantages and limitations. A comprehensive section is devoted to the assessment of portal hypertension, with specific recommendations for the interpretation of liver and spleen stiffness measurements in this setting.

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 screening, evaluation, and management of hepatobiliary disease consensus recommendations

Cystic fibrosis (CF) may cause a spectrum of hepatobiliary complications, including portal hypertension, multilobular cirrhosis, and liver failure. Current guidelines on the detection and monitoring of hepatobiliary complications in CF were published in 1999. The CF Foundation assembled a committee to evaluate research advances and formulate revised guidelines for CF-associated liver disease. A committee of hepatologists, gastroenterologists, pulmonologists, pharmacists, nurses, dietitians, individuals with CF, and the parents of a child with CF devised "population, intervention, comparison, and outcome" questions regarding hepatobiliary disease in CF. PubMed literature searches were performed for each population, intervention, comparison, and outcome question. Recommendations were voted on with 80% agreement required to approve a recommendation. Public comment on initial recommendations was solicited prior to the formulation of final recommendations. Thirty-one population, intervention, comparison, and outcome questions were assembled, 6401 manuscripts were title screened for relevance, with 1053 manuscripts undergoing detailed full-text review. Seven recommendations were approved for screening, 13 for monitoring of existing disease, and 14 for treatment of CF-associated hepatobiliary involvement or advanced liver disease. One recommendation on liver biopsy did not meet the 80% threshold. One recommendation on screening ultrasound was revised and re-voted on. Through a multidisciplinary committee and public engagement, we have assembled updated recommendations and guidance on screening, monitoring, and treatment of CF-associated hepatobiliary involvement and advanced liver disease. While research gaps remain, we anticipate that these recommendations will lead to improvements in CF outcomes through earlier detection and increased evidence-based approaches to monitoring and treatment.

Prospective study of quantitative liver MRI in cystic fibrosis: feasibility and comparison to PUSH cohort ultrasound

BACKGROUND

Pediatric radiologists can identify a liver ultrasound (US) pattern predictive of progression to advanced liver disease. However, reliably discriminating these US patterns remains difficult. Quantitative magnetic resonance imaging (MRI) may provide an objective measure of liver disease in cystic fibrosis (CF).

OBJECTIVE

The purpose of this study was to determine if quantitative MRI, including MR elastography, is feasible in children with CF and to determine how quantitative MRI-derived metrics compared to a research US.

MATERIALS AND METHODS

A prospective, multi-institutional trial was performed evaluating CF participants who underwent a standardized MRI. At central review, liver stiffness, fat fraction, liver volume, and spleen volume were obtained. Participants whose MRI was performed within 1 year of US were classified by US pattern as normal, homogeneous hyperechoic, heterogeneous, or nodular. Each MRI measure was compared among US grade groups using the Kruskal-Wallis test.

RESULTS

Ninety-three participants (51 females [54.8%]; mean 15.6 years [range 8.1-21.7 years]) underwent MRI. MR elastography was feasible in 87 participants (93.5%). Fifty-eight participants had an US within 1 year of MRI. In these participants, a nodular liver had significantly higher stiffness (P<0.01) than normal or homogeneous hyperechoic livers. Participants with a homogeneous hyperechoic liver had a higher fat fraction (P<0.005) than others.

CONCLUSION

MR elastography is feasible in children with CF. Participants with a nodular pattern had higher liver stiffness supporting the US determination of advanced liver disease. Participants with a homogeneous hyperechoic pattern had higher fat fractions supporting the diagnosis of steatosis.

Risk factors for more rapid progression of severe liver fibrosis in children with cystic fibrosis-related liver disease: A multi-center study validated by liver biopsy

BACKGROUND AND AIMS

Early identification of risk factors for the development of severe fibrosis in children with cystic fibrosis-related liver disease (CFLD) is crucial as promising therapies emerge.

METHODS

This multi-center cohort study of children with a priori defined CFLD from 1999 to 2016, was designed to evaluate the clinical utility of CF-specific characteristics and liver biomarkers assessed years prior to liver biopsy-proven CFLD to predict risk of developing severe fibrosis (F3-4) over time. Fibrosis was staged by Metavir classification.

RESULTS

The overall study cohort of 42 patients (F0-2 (n = 22) and F3-4 (n = 20)) was 57% male (n = 24) with median age of 7.6 years at baseline visit versus 10.3 years at biopsy. Median FEV₁ % predicted was lower in F3-4 participants at baseline versus F0-2 (59% vs. 85%; p = .002), while baseline FIB-4, APRI and GGT were higher in F3-4. Median splits for FIB-4 (≥.13), APRI (≥.36), GPR (≥.09), GGT (≥25.5), and FEV₁ % (<64%) were associated with more rapid progression to F3-4 (p < .01 for all). Using a combination of change/year in FIB-4, APRI, and GPR to predict F3-4, the AUROC was .81 (95% CI, .66, .96; p < .0001). For up to 5.8 years prior, thresholds for GPR were met 6.5-fold more rapidly, and those for APRI and FIB-4 were met 2.5-fold more rapidly, in those who progressed to F3-4 than those that did not.

CONCLUSIONS

This study suggests mild-moderate pulmonary dysfunction and higher liver biomarker indices at baseline may be associated with faster progression of CFLD.

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

BACKGROUND AND AIMS

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

APPROACH AND RESULTS

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

CONCLUSIONS

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

Assessment of Liver Fibrosis with the Use of Elastography in Paediatric Patients with Diagnosed Cystic Fibrosis

Background

Complications of cystic fibrosis-associated liver disease (CFLD) are a leading nonpulmonary cause of death. Noninvasive tests enabling early detection of liver changes, especially in children are sought. The aim of the study was to assess the scale of liver fibrosis with the use of elastography in paediatric patients with diagnosed cystic fibrosis (CF) and its comparison with other tests (APRI and Fibrotest).

Methods

We examined 41 children, in the age range 2-21 years, with diagnosed CF. The analysis a included clinical picture, laboratory parameters of liver damage, and cholestasis. Aspartate aminotransferase-to-platelet ratio index (APRI) and Fibrotest were done in all patients. Liver stiffness measurements were acquired using shear-wave elastography (SWE).

Results

CFLD was diagnosed in 16/41 patients (39%). Abnormal elastography was observed in 19/41 patients (46.3%), and in 5/41 (12.2%), the changes were advanced (F4). Abnormal elastography was observed in 12/16 (75%) of the patients with CFLD, and in 7/25 (28%), there were no lesions observed in the liver in the course of cystic fibrosis. In all patients with F4, we observed abnormal results of the APRI and Fibrotest. In most patients with small changes in elastography, we found normal results of the APRI and Fibrotest.

Conclusion

Elastography seems to be a noninvasive examination useful in everyday clinical work in detecting early liver changes and monitoring of progression in paediatric patients with diagnosed cystic fibrosis, ahead of changes in laboratory tests. The cost-effectiveness of this test, the possibility of its repetition, and its availability are additional benefits.

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.

Elastography for Pediatric Chronic Liver Disease: A Review and Expert Opinion

In adults with chronic liver diseases, ultrasound and magnetic resonance shear wave elastography (SWE) can replace liver biopsy in several clinical scenarios. Several guidelines on the use of ultrasound SWE for the adult population have been published. However, the number of publications in the pediatric population is limited, and available guidelines on SWE do not specifically address pediatric chronic liver diseases. In this article, we review the literature on the use of SWE for pediatric chronic liver diseases and provide expert opinion on how to use SWE, both ultrasound and magnetic resonance techniques, in the pediatric population.

Cystic fibrosis foundation consensus statements for the care of cystic fibrosis lung transplant recipients

Cystic fibrosis (CF) is the indication for transplantation in approximately 15% of recipients worldwide, and Cystic Fibrosis Lung Transplant Recipients (CFLTRs) have excellent long-term outcomes. Yet, CFLTRs have unique comorbidities that require specialized care. The objective of this document is to provide recommendations to CF and lung transplant clinicians for the management of perioperative and underlying comorbidities of CFLTRs and the impact of transplantation on these comorbidities. The Cystic Fibrosis Foundation (CFF) organized a multidisciplinary committee to develop CF Lung Transplant Clinical Care Recommendations. Three workgroups were formed to develop focused questions. Following a literature search, consensus recommendations were developed by the committee members based on literature review, committee experience and iterative revisions, and in response to public comment. The committee formulated 32 recommendation statements in the topics related to infectious disease, endocrine, gastroenterology, pharmacology, mental health and family planning. Broadly, the committee recommends close coordination of care between the lung transplant team, the cystic fibrosis care center, and specialists in other disciplines with experience in the care of CF and lung transplant recipients. These consensus statements will help lung transplant providers care for CFLTRs in order to improve post-transplant outcomes in this population.

Diagnostic Performance of Noninvasive Methods for Liver Biopsy by Fibroscan in Pediatric

Liver biopsy is the gold standard for the diagnosis and management of various liver diseases; however, noninvasive diagnostic modalities may help prevent adverse effects of anesthesia, prolonged hospitalization, sampling error, and other serious complications, particularly in pediatric patients. The aim of this study is to compare the results of liver biopsy and fibroscan in children with chronic liver diseases. All patients presenting chronic liver disease admitted in the ward or clinic of Tehran's Children Medical Center were enrolled in the study. Required laboratory tests were performed to diagnose the disease, followed by elastography using fibroscan 402 (M-probe) Echosens machine and liver biopsy using Menghini technique. Samples were scored by using METAVIR scoring system. Thirty-two patients were reported (68.8%, female) with autoimmune hepatitis (18.8%), Wilson disease (12.5%), and glycogen storage disease (12.5%). The most common pathologic stage and fibroscan result was stage III and F0 (46.9%), respectively. Association between pathology and fibroscan results was not significant. Nonetheless, age and diagnosis, age and Fibroscan score, and pathology and liver function test were significantly associated with each other. Fibroscan cannot be used as an alternative to liver biopsy; however, it can be a useful accessory tool.

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.

Nonfasted Liver Stiffness Correlates with Liver Disease Parameters and Portal Hypertension in Pediatric Cholestatic Liver Disease

Elastographic measurement of liver stiffness is of growing importance in the assessment of liver disease. Pediatric experiences with this technique are primarily single center and limited in scope. The Childhood Liver Disease Research Network provided a unique opportunity to assess elastography in a well-characterized multi-institutional cohort. Children with biliary atresia (BA), alpha-1 antitrypsin deficiency (A1ATD), or Alagille syndrome (ALGS) followed in a prospective longitudinal network study were eligible for enrollment in a prospective investigation of transient elastography (FibroScan). Studies were performed in participants who were nonfasted and nonsedated. Liver stiffness measurements (LSMs) were correlated with standard clinical and biochemical parameters of liver disease along with a research definition of clinically evident portal hypertension (CEPH) graded as absent, possible, or definite. Between November 2016 and August 2019, 550 participants with a mean age of 8.8 years were enrolled, 458 of whom had valid LSMs (BA, n = 254; A1ATD, n = 104; ALGS, n = 100). Invalid scans were more common in participants <2 years old. There was a positive correlation between LSM and total bilirubin, international normalized ratio (INR), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), GGT to platelet ratio (GPR), pediatric end-stage liver disease score, AST to platelet ratio index, and spleen size, and a negative correlation with albumin and platelet count in BA, with similar correlations for A1ATD (except AST, ALT, and albumin) and ALGS (except for INR, GGT, GPR, and ALT). Possible or definite CEPH was more common in BA compared to ALGS and A1ATD. LSM was greater in definite versus absent CEPH in all three diseases. Disease-specific clinical and biochemical characteristics of the different CEPH grades were observed. Conclusion: It is feasible to obtain LSMs in children, especially over the age of 2 years. LSM correlates with liver parameters and portal hypertension, although disease-specific patterns exist.

Cystic fibrosis-associated liver disease in children

As improvements in nutritional and pulmonary care increase the life expectancy of cystic fibrosis (CF) patients, CF-associated liver disease (CFLD) is emerging as a cause of mortality. CFLD is the third leading cause of death in CF patients. We performed a search on PubMed and Google Scholar for published articles on CFLD. We reviewed the articles found in the literature search and gave priority to recent publications and studies with larger sample sizes. The prevalence of CFLD in the CF population is around 23% with a range of 2-62% and that prevalence increases linearly with age from 3.7% at age 5 to 32.2% at age 30. CFLD can present clinically in various ways such as hepatomegaly, variceal hemorrhage, persistent elevation of liver enzymes, and micro-gallbladder. Due to the focal nature of fibrosis in majority cases of CFLD, liver biopsies are sparsely performed for diagnosis or the marker of liver fibrosis. Although the mechanism of CFLD development is still unknown, many potential factors are reported. Some mutations of CFTR such as having a homozygous F508del mutation has been reported to increase the risk of developing CFLD and its severity. Having the SERPINA1 Z allele, a history of pancreatic insufficiency, a history meconium ileus, CF-related diabetes, or being male increases the risk of developing CFLD. Environmental factors do not appear to have significant effect on modulating CFLD development. Ursodeoxycholic acid is commonly used to treat or prevent CFLD, but the efficacy of this treatment is questionable.

Hepatic manifestations of cystic fibrosis

PURPOSE OF REVIEW

Liver disease in cystic fibrosis (CF) usually develops before puberty, is often asymptomatic and slowly progressive. Multilobular cirrhosis develops in approximately 5-10% of patients by the age of 18, and is a significant contributor to the morbidity and mortality. No therapy, including ursodeoxycholic acid and cystic fibrosis transmembrane conductance regulator correctors or potentiators, has proven effective to prevent or halt the progression of liver disease towards cirrhosis and portal hypertension. This review provides the current knowledge in the epidemiology of CF liver disease and development of noninvasive tools to assess liver disease severity and progression overtime in order to optimize clinical management and therapeutic options.

RECENT FINDINGS

Liver disease not only develops during childhood but also later in the lifetime of patients with CF; the incidence of cirrhosis with portal hypertension increases progressively reaching 10% by age 30. Several noninvasive tools to measure liver stiffness as an indirect measure of fibrosis are being investigated, and show promising results for the assessment of early stages of liver fibrosis and disease progression.

SUMMARY

Identifying noninvasive biomarkers is fundamental to improving early diagnosis, monitoring disease evolution and measuring treatment effects. A prerequisite is the use of consistent definitions for CF- liver disease (LD) in clinical trials.

Assessment of Selected Parameters of Liver Fibrosis and Inflammation in Patients with Diagnosed Cystic Fibrosis

Changes in the liver and bile ducts observed in patients diagnosed with cystic fibrosis result from inflammatory processes as well as fibrosis, remodeling, apoptosis, and cholestasis. As a consequence, portal hypertension, cirrhosis, and hepatic failure may develop. So far, the complexity of these processes has not been elucidated. Study Objectives. The aim of the study was to evaluate the selected parameters of hepatitis and fibrosis (Fibrotest, Actitest, and APRI) in patients diagnosed with cystic fibrosis. Material and Methods. The study included 79 patients with cystic fibrosis, aged 1 to 20 years (mean age 9.8 years), 49 girls (62%) and 30 boys (38%). The analysis involved the following: age, sex, clinical manifestations, laboratory tests evaluating pancreas function, parameters of liver damage, and cholestasis. Fibrotest, Actitest, and APRI were performed in all subjects. Results. Elevated parameters of hepatic cell damage (hypertransaminasemia) were found in 31/79 (39.2%) patients, while abnormal cholestasis parameters in 21/79 (26.6%). The abnormal results of Fibrotest were reported in 15% of patients (12/79), while of Actitest in 10% (8/79). In contrast, elevated APRI values were found in only 7.6% (6/79) of subjects. There was a statistically significant correlation between APRI and age (higher values were observed in younger children) and between Fibrotest and Actitest and pancreatic insufficiency (higher values were found in subjects without this abnormality). Moreover, Fibrotest values were significantly higher in girls. There was no correlation between Fibrotest, Actitest, and APRI values and the type of mutation. Conclusion. It appears that Fibrotest may be used as an early marker of liver fibrosis in patients with cystic fibrosis. Increased APRI values were only found in subjects with advanced hepatic lesions, most often in the form of portal hypertension.

Heterogeneous Liver on Research Ultrasound Identifies Children with Cystic Fibrosis at High Risk of Advanced Liver Disease: Interim Results of a Prospective Observational Case-Controlled Study

OBJECTIVE

To assess if a heterogeneous pattern on research liver ultrasound examination can identify children at risk for advanced cystic fibrosis (CF) liver disease.

STUDY DESIGN

Planned 4-year interim analysis of a 9-year multicenter, case-controlled cohort study (Prospective Study of Ultrasound to Predict Hepatic Cirrhosis in CF). Children with pancreatic insufficient CF aged 3-12 years without known cirrhosis, Burkholderia species infection, or short bowel syndrome underwent a screening research ultrasound examination. Participants with a heterogeneous liver ultrasound pattern were matched (by age, Pseudomonas infection status, and center) 1:2 with participants with a normal pattern. Clinical status and laboratory data were obtained annually and research ultrasound examinations biannually. The primary end point was the development of a nodular research ultrasound pattern, a surrogate for advanced CF liver disease.

RESULTS

There were 722 participants who underwent screening research ultrasound examination, of which 65 were heterogeneous liver ultrasound pattern and 592 normal liver ultrasound pattern. The final cohort included 55 participants with a heterogeneous liver ultrasound pattern and 116 participants with a normal liver ultrasound pattern. All participants with at least 1 follow-up research ultrasound were included. There were no differences in age or sex between groups at entry. Alanine aminotransferase (42 ± 22 U/L vs 32 ± 19 U/L; P = .0033), gamma glutamyl transpeptidase (36 ± 34 U/L vs 15 ± 8 U/L; P < .001), and aspartate aminotransferase to platelet ratio index (0.7 ± 0.5 vs 0.4 ± 0.2; P < .0001) were higher in participants with a heterogeneous liver ultrasound pattern compared with participants with a normal liver ultrasound pattern. Participants with a heterogeneous liver ultrasound pattern had a 9.1-fold increased incidence (95% CI, 2.7-30.8; P = .0004) of nodular pattern vs a normal liver ultrasound pattern (23% in heterogeneous liver ultrasound pattern vs 2.6% in normal liver ultrasound pattern).

CONCLUSIONS

Research liver ultrasound examinations can identify children with CF at increased risk for developing advanced CF liver disease.

Cystic Fibrosis Liver Disease: Know More

Cystic fibrosis (CF) is a multisystem disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. CFTR is expressed in the apical surface of cholangiocytes. Homozygous CFTR gene mutation results in viscous and acidic bile secretions secondary to deficient surface fluid and bicarbonate efflux. Viscous, inspissated bile causes ductular obstruction and hepatotoxicity from retained bile components, leading to fibrosis and ultimately cirrhosis, known as CF liver disease (CFLD). CFLD is the third leading cause of death in CF patients. CFLD manifestations can take many forms. They range from asymptomatic elevation of transaminases to cirrhosis and end-stage liver disease. CFLD is diagnosed after excluding other causes of chronic liver disease. To date, there is no effective therapy to prevent or treat CFLD. Management of CFLD emphasizes on optimizing nutritional status. Ursodeoxycholic acid is the only available treatment that may prevent progression of CFLD at present. All CF patients with CFLD need annual investigations and follow-up for early detection of the disease. Liver transplantation should be considered in patients with decompensated cirrhosis and portal hypertension, with acceptable long-term outcomes. Novel therapies of CFLD are promising. This review article aims to summarize the published literature on CFLD, its pathophysiology, clinical features and complications, and management including new therapeutic options.

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.

Noninvasive assessment of liver fibrosis in pediatric intestinal failure patients using liver stiffness measurement by Vibration-Controlled Transient Elastography

PURPOSE

The purpose of this study was to evaluate the diagnostic utility of noninvasive Vibration-Controlled Transient Elastography (VCTE) for assessing liver fibrosis in pediatric intestinal failure (PIF) patients.

METHODS

Data from children with severe intestinal failure (≥90 days parenteral nutrition dependence) who underwent liver stiffness measurement (LSM), as measured by VCTE, at our institution between December 2015 and March 2018 were reviewed. LSM was compared to METAVIR fibrosis score (F0-F4) on liver biopsy performed within 1 year of VCTE.

RESULTS

Seventy children underwent 75 LSM. Sixty-three patients (38% female) had at least one valid LSM, and 63% had a history of cholestasis (direct bilirubin ≥2 mg/dL). Median (IQR) age at first valid LSM was 4.5 years (2.6, 8.7). Sixteen patients had a liver biopsy. LSM differentiated between METAVIR F0-F1 (n = 6) and F2-F4 (n = 10) with an area under the receiver operating characteristic (AUROC) curve of 0.883 (95% CI: 0.686-0.999). The optimal cut-point derived to predict F2-F4 was an LSM ≥6 kPa (sensitivity 80%, specificity 100%).

CONCLUSION

LSM as determined by VCTE can distinguish mild (F0-F1) from moderate/severe (F2-F4) liver fibrosis in PIF. VCTE could allow for serial noninvasive monitoring of liver injury, potentially facilitating timely modifications to hepatoprotective management.

TYPE OF STUDY

Study of Diagnostic Test.

LEVEL OF EVIDENCE

II.

Hepatic Manifestations of Cystic Fibrosis

Cystic fibrosis liver disease (CFLD) remains the third leading cause of death in patients with cystic fibrosis. Although most patients with CFLD present in childhood, recent studies suggest a second wave of liver disease in adulthood. There are no clear guidelines for diagnosing CFLD. Treatment options for CFLD remain limited, and while UDCA is widely used, its long-term benefit is unclear. Those who develop hepatic decompensation or uncontrolled variceal bleeding may benefit from liver transplant, either alone, or in combination with lung transplant.

A Multidisciplinary Approach to Pretransplant and Posttransplant Management of Cystic Fibrosis-Associated Liver Disease

Approximately 5%-10% of patients with cystic fibrosis (CF) will develop advanced liver disease with portal hypertension, representing the third leading cause of death among patients with CF. Cystic fibrosis with advanced liver disease and portal hypertension (CFLD) represents the most significant risk to patient mortality, second only to pulmonary or lung transplant complications in patients with CF. Currently, there is no medical therapy to treat or reverse CFLD. Liver transplantation (LT) in patients with CFLD with portal hypertension confers a significant survival advantage over those who do not receive LT, although the timing in which to optimize this benefit is unclear. Despite the value and efficacy of LT in selected patients with CFLD, established clinical criteria outlining indications and timing for LT as well as disease-specific transplant considerations are notably absent. The goal of this comprehensive and multidisciplinary report is to present recommendations on the unique CF-specific pre- and post-LT management issues clinicians should consider and will face.

Diagnostic Performance of Ultrasound Elastography for Evaluating Portal Hypertension in Children: A Systematic Review and Meta-analysis

OBJECTIVES

To assess the diagnostic performance of ultrasound (US) elastography in evaluating portal hypertension in children and compare the liver and spleen stiffness values between the portal hypertension and control groups.

METHODS

Studies in the MEDLINE and Embase databases were selected that investigated the diagnostic performance of US elastography in children with portal hypertension up to December 21, 2017. Pooled sensitivity and specificity data were assessed by hierarchical logistic regression modeling.

RESULTS

Eleven studies were included in the systematic review, and a meta-analysis could be conducted in 7 of these publications to evaluate the diagnostic performance of US elastography. The summary sensitivity and specificity of this method for liver stiffness were 90% (95% confidence interval [CI], 83%-94%) and 79% (95% CI, 73%-84%), respectively, and the area under the hierarchical summary receiver operating characteristic curve was 0.92 (95% CI, 0.90-0.94). A subgroup analysis of 5 transient elastographic studies revealed similar diagnostic performance (sensitivity, 90%; specificity, 78%). In 10 of the 11 studies that investigated liver stiffness and 2 of the 3 studies that also measured spleen stiffness, patients in the portal hypertension group had a significantly higher stiffness value than the control group (P < .05).

CONCLUSIONS

Ultrasound elastography shows good performance in diagnosing portal hypertension and can identify significant differences in liver and spleen stiffness in children with this condition. This method thus has considerable potential as a noninvasive tool for screening portal hypertension-related complications in children with chronic liver disease.

Advances in diagnosis of chronic liver diseases in pediatric patients

BACKGROUND

Chronic liver diseases (CLD) present important clinical problem in children with various age-dependent causes. Nonalcoholic fatty liver disease (NAFLD) with its increasing prevalence is a major problem with regard to its timely recognition and the need for long-term disease monitoring. At present, a perfect non-invasive method for the evaluation of liver fibrosis is not available.

METHODS

A non-systematic literature search was performed to summarize the current knowledge about transient elastography (TE) with controlled attenuation parameter (CAP) in children with CLD. Ovid MEDLINE, Ovid EMBASE, Google scholar, and The Cochrane Library databases were searched for relevant articles evaluating TE in the pediatric population.

RESULTS

Normal values of liver stiffness measurements (LSM) according to the age are given, as well as the advantages and disadvantages of the method. The utility of TE in specific liver disease in pediatric population is summarized.

CONCLUSIONS

TE with CAP is a valuable non-invasive method for the liver-damage assessment. Clinical interpretation of TE results should be made in parallel with the assessment of the patient's demographics, disease etiology, and essential laboratory parameters.

Controlled attenuation parameter: A measure of hepatic steatosis in patients with cystic fibrosis

BACKGROUND

Hepatic steatosis is a common manifestation of CF-related liver disease(CFLD). Controlled attenuation parameter(CAP) measurement during transient elastography(TE) semiquantifies liver steatosis. We examined the relationship between CAP and CFLD severity, clinical factors and liver stiffness measurements(LSM).

METHODS

This is a cross-sectional study of CF patients seen for outpatient care between January 2013-March 2014. CFLD severity was categorized as no CFLD, CFLD without portal hypertension(PHTN) and CFLD with PHTN, based on published criteria.

RESULTS

129 patients (median 18.4y; 57% male) had valid CAP. 70(54%) had no CFLD, 44(34%) CFLD without PHTN, and 15(12%) CFLD with PHTN. The median CAP was 210 dB/m (IQR 181-239). Steatosis(CAP ≥230 dB/m) was seen in 27% of subjects without CFLD, 48% in CFLD but no PHTN, and 20% in with CFLD and PHTN(P = .04). CAP was higher for subjects with CFLD without PHTN (P < .05). There was no CAP difference between subjects with no CFLD and those with CFLD and PHTN (P ≥ .65). LSM was not different between no CFLD and CFLD without PHTN (P = .07), but each of these groups had lower LSM compared to subjects with CFLD and PHTN(P < .001 for each). Except for direct bilirubin, CAP was not associated with clinical markers of liver disease.

CONCLUSION

CAP was normal in 86(67%) of patients with CF and was not associated with standard clinical markers of liver disease. CAP was higher in patients with liver disease, which could possibly reflect the loss of steatosis observed with progression to cirrhosis and portal hypertension.

Point shear wave elastography of the pancreas in patients with cystic fibrosis: a comparison with healthy controls

PURPOSE

Manifestations of cystic fibrosis in the pancreas are gaining in clinical importance as patients live longer. Conventional ultrasonography and point shear wave elastography (pSWE) imaging are non-invasive and readily available diagnostic methods that are easy to perform. The aim of this study was to perform conventional ultrasonography and obtain pSWE values in the pancreases of patients with cystic fibrosis and to compare the findings with those of healthy controls.

METHODS

27 patients with cystic fibrosis (13 women/14 men; mean age 27.7 ± 13.7 years; range 9-58 years) and 60 healthy control subjects (30 women/30 men; mean age 30.3 ± 10.0 years; range 22-55 years) underwent examinations of the pancreas with conventional ultrasound and pSWE imaging.

RESULTS

Patients with cystic fibrosis have an echogenic pancreatic parenchyma. We found cystic lesions of the pancreas in six patients. pSWE imaging of the pancreatic parenchyma gave significantly lower shear wave velocities in patients with cystic fibrosis than in the control group (1.01 m/s vs 1.30 m/s; p < 0.001).

CONCLUSIONS

Using pSWE imaging in vivo, we have shown that the pancreas is considerably softer in patients with cystic fibrosis than in a healthy control population.

Cystic fibrosis year in review 2017

In this article, we highlight cystic fibrosis (CF) reports published in Pediatric Pulmonology during 2017. We also include articles from a variety of journals that are related or are of special interest to clinicians.

Transient Elastography in the Evaluation of Cystic Fibrosis-Associated Liver Disease: Systematic Review and Meta-analysis

Background and aims

Complications of cystic fibrosis-associated liver disease (CFLD) are a leading nonpulmonary cause of death. Transient elastography (TE) has recently been investigated to detect CFLD. This study reviews the current literature for TE in the detection CFLD. A meta-analysis was performed to determine the ideal liver stiffness measurement (LSM) cutoff.

Methods

PubMed, Medline, EMBASE and Web of Science were searched from inception until April 2016 for publications involving the detection of CFLD with TE. Data were extracted using a fixed protocol (a priori design) including study design, population characteristics, probe size and AST Platelet Ratio Index (APRI).

Results

Diagnostic properties were summarized from six studies of 605 patients. Cutoff for LSM was determined using pooled data submitted by authors. The cutoff for LSM and APRI were ≥5.95 kPa and ≥0.329 respectively, yielding a sensitivity, specificity and area under receiver operator characteristic of 55%, 87%, 0.76, 52%, 93% and 0.84 for LSM and APRI, respectively. When LSM ≥5.95 kPa and APRI ≥0.329, the sensitivity, specificity, positive predictive value and negative predictive value were 43%, 99%, 92% and 87% with a diagnostic odds ratio of 74.9. A bivariate metaregression model showed that pediatric specific cutoffs for liver stiffness and APRI may not be necessary.

Conclusion

Individually, LSM and APRI have poor sensitivity but good specificity for detecting CFLD. They are most useful when combined. We propose that patients with LSM ≥5.95 kPa and APRI ≥0.329 be investigated thoroughly for the presence of cystic fibrosis-associated liver disease.

Liver disease in patients with cystic fibrosis

PURPOSE OF REVIEW

The aim of this study was to provide an overview of the current understanding of the pathophysiology, diagnosis and management of cystic fibrosis-liver disease (CFLD).

RECENT FINDINGS

CFLD has a variety of manifestations. Previously, it was thought that patients progressed from mild cholestatic disease to cirrhosis to decompensated cirrhosis with portal hypertension. Newer evidence suggests that some patients may develop cirrhosis while others develop noncirrhotic portal hypertension. Advances in our understanding of the pathophysiology of disease necessitate modifications to the current diagnostic criteria. Both fibroscan and noninvasive biomarkers can be used to identify patients with cirrhosis and portal hypertension. Ursodeoxycholic acid remains the mainstay of therapy despite a paucity of rigorous studies supporting its use. Novel therapeutic agents such as CF transmembrane conductance regulator (CFTR) modulators and potentiators are encouraging but need to be evaluated specifically in CFLD.

SUMMARY

A better understanding of the pathophysiology of disease is critical to developing more disease-specific diagnostics and therapeutics.

Diagnosis, follow-up and treatment of cystic fibrosis-related liver disease

PURPOSE OF REVIEW

To provide an insight and overview of the challenges in the diagnosis, follow-up and treatment of cystic fibrosis-related liver disease (CFLD).

RECENT FINDINGS

The variable pathophysiology of CFLD complicates its diagnosis and treatment. A 'gold standard' for CFLD diagnosis is lacking. Over the past years, new techniques to diagnose features of CFLD, such as transient elastography, have been investigated. Although most of these tests confirm cystic fibrosis-related liver involvement (CFLI), they are, however, not suitable to distinguish various phenotypical presentations or predict progression to clinically relevant cirrhosis or portal hypertension. A combined initiative from the European and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition has been started, aimed to obtain consensus on CFLD criteria and definitions. Currently, only ursodeoxycholic acid is used in CFLD treatment, although it has not been convincingly demonstrated to change the natural course of the disease. Drugs that directly target cystic fibrosis transmembrane conductance regulator protein dysfunction show promising results; however, more long-term follow-up and validation studies are needed.

SUMMARY

CFLD is an umbrella term referring to a wide variety of liver manifestations with variable clinical needs and consequences. CFLD with portal hypertension is the most severe form of CFLD due to its significant implications on morbidity and mortality. The clinical relevance of other CFLI is uncertain. Consensus on CFLD definitions is essential to validate new diagnostic tools and therapeutic outcome measures.

Adult-onset cystic fibrosis liver disease: Diagnosis and characterization of an underappreciated entity

Cystic fibrosis (CF) liver disease (CFLD), a leading cause of death in CF, is mostly described in pediatric populations. Adult-onset CFLD lacks sufficient characterization and diagnostic tools. A cohort of CF patients without CFLD during childhood were followed for up to 38 years with serologic testing, imaging, and noninvasive fibrosis markers. Historical CFLD diagnostic criteria were compared with newly proposed CFLD criteria. Thirty-six CF patients were followed for a median of 24.5 years (interquartile range 15.6-32.9). By the last follow-up, 11 (31%) had died. With conventional criteria, 8 (22%) patients had CFLD; and by the new criteria, 17 (47%) had CFLD at a median age of 36.6 years (interquartile range 26.5-43.2). By the new criteria, those with CFLD had higher median alanine aminotransferase (42 versus 27, P = 0.005), aspartate aminotransferase (AST; 26 versus 21, P = 0.01), direct bilirubin (0.13 versus 0.1, P = 0.01), prothrombin time (14.4 versus 12.4, P = 0.002), and AST-to-platelet ratio index (0.31 versus 0.23, P = 0.003) over the last 2 years of follow-up. Subjects with a FibroScan >6.8 kPa had higher alanine aminotransferase (42 versus 28U/L, P = 0.02), AST (35 versus 25U/L, P = 0.02), AST-to-platelet ratio index (0.77 versus 0.25, P = 0.0004), and Fibrosis-4 index (2.14 versus 0.74, P = 0.0003) and lower platelet counts (205 versus 293, P = 0.02). One CFLD patient had nodular regenerative hyperplasia. Longitudinally, mean platelet counts significantly declined in the CFLD group (from 310 to 230 U/L, P = 0.0005). Deceased CFLD patients had lower platelet counts than those alive with CFLD (143 versus 258 U/L, P = 0.004) or those deceased with no CFLD (143 versus 327U/L, P = 0.006).

CONCLUSION

Adult-onset CFLD may be more prevalent than previously described, which suggests a later wave of CFLD that impacts morbidity; routine liver tests, radiologic imaging, noninvasive fibrosis markers, and FibroScan can be used algorithmically to identify adult CFLD; and further evaluation in other CF cohorts should be performed for validation. (Hepatology 2017;66:591-601).