Shear-wave elastography for monitoring Fontan-associated liver disease: A prospective cohort study.

The spectrum of Fontan-associated liver disease (FALD) varies from abnormal liver function tests to fibrosis and even cirrhosis. In this prospective study, we evaluated the role of shear-wave elastography (SWE) in predicting the presence of advanced FALD. Forty-eight patients (30 males, 13.9 [6-21] years) with a Fontan circulation were evaluated at 8.3 (2.1-18.7) years since the Fontan surgery. The median liver stiffness measurement (LSM) value was higher than values in normal children at 15.4 (9.5-38.7) kPa. The LSMs had a weak but significant correlation with age at the time of LSM (r = 0.25, p = 0.01) and duration post-Fontan surgery (r = 0.31, p = 0.02). It had a poor correlation with the concomitant aspartate transaminase-to-platelet ratio index (r = 0.1, p = 0.39). No difference in the elastography values between children with and without ultrasound evidence of advanced liver disease (17.7 [interquartile range, IQR: 4] vs. 16.1 [IQR: 6], p = 0.62] was observed. Further studies are required to determine the precise role of SWE as a noninvasive marker of liver fibrosis in FALD.

Recommendations for Standardizing MRI-based Evaluation of Perianal Fistulizing Disease Activity in Pediatric Crohn's Disease Clinical Trials.

BACKGROUND: Perianal fistulas and abscesses occur commonly as complications of pediatric Crohn's disease (CD). A validated imaging assessment tool for quantification of perianal disease severity and activity is needed to evaluate treatment response. We aimed to identify magnetic resonance imaging (MRI)-based measures of perianal fistulizing disease activity and study design features appropriate for pediatric patients. METHODS: Seventy-nine statements relevant to MRI-based assessment of pediatric perianal fistulizing CD activity and clinical trial design were generated from literature review and expert opinion. Statement appropriateness was rated by a panel (N = 15) of gastroenterologists, radiologists, and surgeons using modified RAND/University of California Los Angeles appropriateness methodology. RESULTS: The modified Van Assche Index (mVAI) and the Magnetic Resonance Novel Index for Fistula Imaging in CD (MAGNIFI-CD) were considered appropriate instruments for use in pediatric perianal fistulizing disease clinical trials. Although there was concern regarding the use of intravascular contrast material in pediatric patients, its use in clinical trials was considered appropriate. A clinically evident fistula tract and radiologic disease defined as at least 1 fistula or abscess on pelvic MRI were considered appropriate trial inclusion criteria. A coprimary clinical and radiologic end point and inclusion of a patient-reported outcome were also considered appropriate. CONCLUSION: Outcomes of treatment of perianal fistulizing disease in children must include MRI. Existing multi-item measures, specifically the mVAI and MAGNIFI-CD, can be adapted and used for children. Further research to assess the operating properties of the indices when used in a pediatric patient population is ongoing.

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.

Characterization of CFTR mutations in people with cystic fibrosis and severe liver disease who are not eligible for CFTR modulators.

Cystic-fibrosis-related liver disease (CFLD) is a variable phenotype of CF. The severe CFLD variant with cirrhosis or portal hypertension has a poor prognosis and life expectancy. CFTR modulator therapies are now available for people with CF and eligibility for such treatment is based on their CFTR genotype. We evaluated the genetic eligibility for elexacaftor, tezacaftor, ivacaftor (ETI), and ivacaftor (IVA) monotherapy in a previously reported CF cohort of 1591 people with CF of whom 171 with severe CFLD. Based on their CFTR mutations, 13% (N=184/1420) of subjects without CFLD and 11% (N=19/171) of those with severe CFLD are not eligible for either ETI or IVA therapy. The non-eligible patients without CFLD or with severe CFLD can currently not take advantage of the potential benefits of these new treatments. Although this study cannot provide any data regarding the effect of ETI or IVA on the progression of severe CFLD, the consequences for ineligibility of patients with extreme liver phenotype may be even more significant because of their poorer disease risk profile.

Ursodeoxycholic acid and liver disease associated with cystic fibrosis: A multicenter cohort study.

BACKGROUND: The efficacy and safety of ursodeoxycholic acid (UDCA) for the treatment of liver disease associated with cystic fibrosis (CF) are under discussion, and clinical practice varies among centers. The study aimed at evaluating if the incidence of severe liver disease differs between CF centers routinely prescribing or not prescribing UDCA. METHODS: We carried out a retrospective multicenter cohort study including 1591 CF patients (1192 patients from UDCA-prescribing centers and 399 from non-prescribing centers) born between 1990 and 2007 and followed from birth up to 31 December 2016. We computed the crude cumulative incidence (CCI) of portal hypertension (PH) at the age of 20 years in the two groups and estimated the subdistribution hazard ratio (HR) through a Fine and Gray model. RESULTS: Over the observation period, 114 patients developed PH: 90 (7.6%) patients followed-up in UDCA prescribing centers and 24 (6.0%) in non-prescribing centers. The CCI of PH at 20 years was 10.1% (95% CI: 7.9-12.3) in UDCA-prescribing and 7.7% (95% CI: 4.6-10.7) in non-prescribing centers. The HR among patients followed in prescribing centers indicated no significant difference in the rate of PH either in the unadjusted model (HR: 1.21, 95% CI: 0.69-2.11) or in the model adjusted for pancreatic insufficiency (HR: 1.28, 95% CI: 0.77-2.12). CONCLUSIONS: CF patients followed-up in UDCA prescribing centers did not show a lower incidence of PH as compared to those followed in centers not prescribing UDCA. These results question the utility of UDCA in reducing the occurrence of severe liver disease in CF.

Advanced but not mild liver disease is a predictor of decreased survival in children with cystic fibrosis, with far greater impact in females: A 27-year real-life cohort study.

BACKGROUND: Improved survival of children with CF has increased our need to understand the relevance of cystic fibrosis-associated liver disease (CFLD). We assessed the impact of liver disease and disease severity on the survival of children with cystic fibrosis. METHODS: A real life, single center cohort study with 27 years follow up was conducted. Mild CFLD was diagnosed as children with abnormal serum liver function tests and abnormal ultrasound. Advanced CFLD was established by detection of cirrhosis or portal hypertension. A directed acyclic graph, Kaplan-Meier (KM) and Cox regression analysis were used to model survival. RESULTS: 290 patients were enrolled, 48 (16.5%) had mild CFLD and 55 (19%) had advanced CFLD. Ten children with advanced CFLD and 1 with mild CFLD died. Based on the KM analysis, the mean (SE) overall survival age of all CF children was 29.1 years (0.50). The mean (SE) survival among females with advanced CFLD was 24.7 years (1.58) compared to 30.4 years (0.66) for females without advanced CFLD (p = 0.0027). Advanced CFLD was a predictor of decreased survival when adjusted for sex and diabetes (HR 2.54, 95%CI 1.05-6.15, p = 0.039). Mild CFLD was not associated with decreased survival. The effect of advanced CFLD on survival was mainly borne by females (HR = 6.37, 95%CI 1.62-25.06 vs. males, HR = 1.00, 95%CI 0.25-4.01). CONCLUSION: Advanced but not mild CFLD was associated with an increased risk of death when adjusted for sex and diabetes, and resulted in premature death in females with cystic fibrosis by approximately 6 years.

Gamma-glutamyl transpeptidase-to-platelet ratio as a biomarker of liver disease and hepatic fibrosis severity in paediatric Cystic Fibrosis.

BACKGROUND: Cystic fibrosis (CF)-associated liver disease (CFLD) causes significant morbidity and mortality in children with CF. Diagnosis of liver disease prior to development of cirrhosis or portal hypertension (PHT) is challenging. While imaging modalities using Elastography show great promise they are still not widely available to all clinicians. This study investigated gamma-glutamyl transpeptidase-to-platelet ratio (GPR) as a non-invasive biomarker to detect liver disease and stage fibrosis severity in children with CF. METHODS: 237 children were enroled including 76 with CFLD and 161 with CF and no detectable liver disease (CFnoLD). CFLD was diagnosed using standard clinical, biochemical and imaging practice guidelines. Hepatic fibrosis was staged on liver biopsies available from 54 children with CFLD. Serum liver biochemistry was used to calculate GPR (median, [IQR]) and receiver operating characteristics (ROC) analysis assessed utility to detect liver disease and stage fibrosis severity. RESULTS: GPR was significantly increased in CFLD versus CFnoLD (0.33 [0.19-0.96] vs. 0.15 [0.11-0.21], P<0.0001). GPR demonstrated good diagnostic utility for detecting CFLD with an area under the curve (AUC) of 0.81 (95% confidence Interval [CI] [0.75-0.87]; P<0.0001), with sensitivity of 74% and specificity of 73%, using a cut-off of 0.20. GPR increased with increasing hepatic fibrosis stage. GPR discriminated both moderate-advanced (F2-F4) fibrosis vs. F0-F1 (AUC=0.82; 95%CI [0.71-0.94]; P<0.0001) and advanced (F3-F4) fibrosis vs. F0-F2 (AUC=0.77; 95%CI [0.64-0.90]; P = 0.004), with a cut-off 0.32 and 0.61, respectively. An elevated GPR of >0.84 was predictive of PHT at diagnosis of CFLD (AUC=0.81; 95%CI [0.67-0.95]; P = 0.0003). CONCLUSIONS: GPR demonstrates good diagnostic utility for assessing the presence of liver disease, PHT and hepatic fibrosis severity in children with CF. These findings will aid in better identification of patients at risk for CF-related liver involvement and the potential for more targeted and timely follow-up and treatment.

Standardisation of intestinal ultrasound scoring in clinical trials for luminal Crohn's disease.

BACKGROUND: Intestinal ultrasound (IUS) is a valuable tool for assessment of Crohn's disease (CD). However, there is no widely accepted luminal disease activity index. AIMS: To identify appropriate IUS protocols, indices, items, and scoring methods for measurement of luminal CD activity and integration of IUS in CD clinical trials. METHODS: An expert international panel of adult and paediatric gastroenterologists (n = 15) and radiologists (n = 3) rated the appropriateness of 120 statements derived from literature review and expert opinion (scale of 1-9) using modified RAND/UCLA methodology. Median panel scores of 1 to ≤3.5, >3.5 to <6.5 and ≥6.5 to 9 were considered inappropriate, uncertain and appropriate ratings respectively. The statement list and survey results were discussed prior to voting. RESULTS: A total of 91 statements were rated appropriate with agreement after two rounds of voting. Items considered appropriate measures of disease activity were bowel wall thickness (BWT), vascularity, stratification and mesenteric inflammatory fat. There was uncertainty if any of the existing IUS disease activity indices were appropriate for use in CD clinical trials. Appropriate trial applications for IUS included patient recruitment qualification when diseased segments cannot be adequately assessed by ileocolonoscopy and screening for exclusionary complications. At outcome assessment, remission endpoints including BWT and vascularity, with or without mesenteric inflammatory fat, were considered appropriate. Components of an ideal IUS disease activity index were identified based upon panel discussions. CONCLUSIONS: The panel identified appropriate component items and applications of IUS for CD clinical trials. Empiric evidence, and development and validation of an IUS disease activity index are needed.

Supersonic shear-wave elastography and APRI for the detection and staging of liver disease in pediatric cystic fibrosis.

BACKGROUND: Current diagnostic methods for the diagnosis of Cystic fibrosis (CF)-associated liver disease (CFLD) are non-specific and assessment of disease progression is difficult prior to the advent of advanced disease with portal hypertension. This study investigated the potential of Supersonic shear-wave elastography (SSWE) to non-invasively detect CFLD and assess hepatic fibrosis severity in children with CF. METHODS: 125 children were enrolled in this study including CFLD (n = 55), CF patients with no evidence of liver disease (CFnoLD = 41) and controls (n = 29). CFLD was diagnosed using clinical, biochemical and imaging best-practice guidelines. Advanced CFLD was established by the presence of portal hypertension and/or macronodular cirrhosis on ultrasound. Liver stiffness measurements (LSM) were acquired using SSWE and diagnostic performance for CFLD detection was evaluated alone or combined with aspartate aminotransferase-to-platelet ratio index (APRI). RESULTS: LSM was significantly higher in CFLD (8.1 kPa, IQR = 6.7-11.9) versus CFnoLD (6.2 kPa, IQR = 5.6-7.0; P < 0.0001) and Controls (5.3 kPa, IQR = 4.9-5.8; P < 0.0001). LSM was also increased in CFnoLD versus Controls (P = 0.0192). Receiver Operating Characteristic (ROC) curve analysis demonstrated good diagnostic accuracy for LSM in detecting CFLD using a cut-off = 6.85 kPa with an AUC = 0.79 (Sensitivity = 75%, Specificity = 71%, P < 0.0001). APRI also discriminated CFLD (AUC = 0.74, P = 0.004). Classification and regression tree modelling combining LSM + APRI showed 14.8 times greater odds of accurately predicting CFLD (AUC = 0.84). The diagnostic accuracy of SSWE for discriminating advanced disease was excellent with a cut-off = 9.05 kPa (AUC = 0.95; P < 0.0001). CONCLUSIONS: SSWE-determined LSM shows good diagnostic accuracy in detecting CFLD in children, which was improved when combined with APRI. SSWE alone discriminates advanced CFLD.

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.

Utility of proactive infliximab levels in paediatric Crohn's disease.

OBJECTIVE: Infliximab (IFX) has an established role in Crohn's disease (CD), with serum trough levels of IFX (TLI) increasingly used to optimise dosing. We report the utility of routine, proactive TLI in children on combination therapy with immunosuppression (IS) from a single paediatric centre. METHODS: This is a retrospective chart review of all children with CD receiving IFX therapy conducted betweenJanuary 2014-May 2017. Clinical phenotype, duration of therapy, TLI (µg/mL), drug antibodies, type of IS, biomarkers and changes in management were recorded. RESULTS: 60 children (8-17 years; median 14.1 years) had 206 TLIs recorded. 56/60 (93%) were on IS, with 5/60 (8%) developing antidrug antibodies (ADAs). 63/206 TLIs were recorded duringan episode of relapse (median 3.0 µg/mL) vs 143/206 TLIs recorded in remission (median 5.2 µg/mL). For children with TLI <3 µg/mL, 31/63 (49%) were in relapse vs 30/143 (21%) in remission. For children with TLI >7 µg/mL, 7/63 (11%) were in relapse vs 46/143 (32%) in remission. Change in management resulted from 43/206 (21%) TLIs in 31/60 (52%) children: 21 dose escalations, 12 de-escalations and 10 changed to adalimumab. Of 31 postinduction TLIs, 15/17 (88%) children with TLI >7 µg/mL achieved clinical and biochemical remission for the duration of therapy (median 14 months), while 4/5 (80%) children with TLI <3 µg/mL required early dose escalation. Combination therapy with thiopurines (TP) (median TLI 4.9 µg/mL) versus methotrexate (MTX) (median TLI 5.2 µg/mL) achieved comparable levels with no difference in relapse frequency. CONCLUSIONS: Routine, proactive TLIs guide optimal management in children with CD. Postinduction and during maintenance, levels <3 µg/mL were associated with relapse and levels >7 µg/mL with sustained remission. Combination IS with TP and MTX appears to offer comparable TLI and ADA rates.

MicroRNA Sequencing Identifies a Serum MicroRNA Panel, Which Combined With Aspartate Aminotransferase to Platelet Ratio Index Can Detect and Monitor Liver Disease in Pediatric Cystic Fibrosis.

Cystic fibrosis (CF)-associated liver disease (CFLD) is a hepatobiliary complication of CF. Current diagnostic modalities rely on nonspecific assessments, whereas liver biopsy is the gold standard to assess severity of fibrosis. MicroRNAs (miRNAs) regulate liver disease pathogenesis and are proposed as diagnostic biomarkers. We investigated the combined use of serum miRNAs and aspartate aminotransferase (AST) to platelet ratio (APRI) to diagnose and assess CFLD severity. This was a cross-sectional cohort study of the circulatory miRNA signature of 124 children grouped by clinical, biochemical, and imaging assessments as follows: CFLD (n = 44), CF patients with no evidence of liver disease (CFnoLD; n = 40), and healthy controls (n = 40). Serum miRNAs were analyzed using miRNA sequencing (miRNA-Seq). Selected differentially expressed serum miRNA candidates were further validated by qRT-PCR and statistical analysis performed to evaluate utility to predict CFLD and fibrosis severity validated by liver biopsy, alone or in combination with APRI. Serum miR-122-5p, miR-365a-3p, and miR-34a-5p levels were elevated in CFLD compared to CFnoLD, whereas miR-142-3p and let-7g-5p were down-regulated in CFLD compared to CFnoLD. Logistic regression analysis combining miR-365a-3p, miR-142-3p, and let-7g-5p with APRI showed 21 times greater odds of accurately predicting liver disease in CF with an area under the receiver operating characteristics curve (AUROC) = 0.91 (sensitivity = 83%, specificity = 92%; P < 0.0001). Expression levels of serum miR-18a-5p were correlated with increasing hepatic fibrosis (HF) stage in CFLD (rs  = 0.56; P < 0.0001), showing good diagnostic accuracy for distinguishing severe (F3-F4) from mild/moderate fibrosis (F0-F2). A unit increase of miR-18a-5p showed a 7-fold increased odds of having severe fibrosis with an AUROC = 0.82 (sensitivity = 93%, specificity = 73%; P = 0.004), indicating its potential to predict fibrosis severity. Conclusion: We identified a distinct circulatory miRNA profile in pediatric CFLD with potential to accurately discriminate liver disease and fibrosis severity in children with CF.

Taurocholate Induces Biliary Differentiation of Liver Progenitor Cells Causing Hepatic Stellate Cell Chemotaxis in the Ductular Reaction: Role in Pediatric Cystic Fibrosis Liver Disease.

Cystic fibrosis liver disease (CFLD) in children causes progressive fibrosis leading to biliary cirrhosis; however, its cause(s) and early pathogenesis are unclear. We hypothesized that a bile acid-induced ductular reaction (DR) drives fibrogenesis. The DR was evaluated by cytokeratin-7 immunohistochemistry in liver biopsies, staged for fibrosis, from 60 children with CFLD, and it demonstrated that the DR was significantly correlated with hepatic fibrosis stage and biliary taurocholate levels. To examine the mechanisms involved in DR induction, liver progenitor cells (LPCs) were treated with taurocholate, and key events in DR evolution were assessed: LPC proliferation, LPC biliary differentiation, and hepatic stellate cell (HSC) chemotaxis. Taurocholate induced a time-dependent increase in LPC proliferation and expression of genes associated with cholangiocyte differentiation (cytokeratin 19, connexin 43, integrin ß4, and γ-glutamyltranspeptidase), whereas the hepatocyte specification marker HNF4α was suppressed. Functional cholangiocyte differentiation was demonstrated via increased acetylated α-tubulin and SOX9 proteins, the number of primary cilia+ LPCs, and increased active γ-glutamyltranspeptidase enzyme secretion. Taurocholate induced LPCs to release MCP-1, MIP1α, and RANTES into conditioned medium causing HSC chemotaxis, which was inhibited by anti-MIP1α. Immunofluorescence confirmed chemokine expression localized to CK7+ DR and LPCs in CFLD liver biopsies. This study suggests that taurocholate is involved in initiating functional LPC biliary differentiation and the development of the DR, with subsequent induction of chemokines that drive HSC recruitment in CFLD.

Function and Regulation of MicroRNAs and Their Potential as Biomarkers in Paediatric Liver Disease.

MicroRNAs (miRNAs) are short non-coding RNAs involved in biological and pathological processes of every cell type, including liver cells. Transcribed from specific genes, miRNA precursors are processed in the cytoplasm into mature miRNAs and as part of the RNA-induced silencing complex (RISC) complex binds to messenger RNA (mRNA) by imperfect complementarity. This leads to the regulation of gene expression at a post-transcriptional level. The function of a number of different miRNAs in fibrogenesis associated with the progression of chronic liver disease has recently been elucidated. Furthermore, miRNAs have been shown to be both disease-and tissue-specific and are stable in the circulation, which has led to increasing investigation on their utility as biomarkers for the diagnosis of chronic liver diseases, including those in children. Here, we review the current knowledge on the biogenesis of microRNA, the mechanisms of translational repression and the use of miRNA as circulatory biomarkers in chronic paediatric liver diseases including cystic fibrosis associated liver disease, biliary atresia and viral hepatitis B.

Towards an integrated understanding of the therapeutic utility of exclusive enteral nutrition in the treatment of Crohn's disease.

Crohn's disease (CD) is a chronic disease characterized by episodic and disabling inflammation of the gastrointestinal tract in genetically susceptible individuals. The incidence and prevalence of CD is rising rapidly across the world emphasising that disease risk is also influenced by environmental and lifestyle factors, as well as the microbial community resident in the gut. Childhood-onset CD is associated with an aggressive disease course that can adversely impact patient growth and development. There is no cure for CD however new onset and recurrent cases of paediatric CD are often responsive to exclusive enteral nutrition (EEN) treatment. EEN treatment involves the exclusive consumption of an elemental or polymeric formula for several weeks and it is well established as a primary intervention strategy. EEN treatments typically achieve remission rates of over 80% and importantly they are associated with a high rate of mucosal healing, far superior to steroids, which is prognostic of improved long-term health outcomes. Furthermore, they are safe, have few side effects, and improve nutritional status and linear growth. Surprisingly, despite the utility of EEN our understanding of the host-microbe-diet interactions that underpin clinical remission and mucosal healing are limited. Here, we review the current state of knowledge and propose that the induction of autophagy, in addition to modulation of the microbiota and coordinated effects on inflammation and epithelial cell biology, may be critical for the therapeutic effects associated with EEN. A better understanding of EEN treatment will provide new opportunities to restore gut homeostasis and prolong periods of remission, as well as provide new insights into the factors that trigger and perhaps prevent CD.

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

UNLABELLED: 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.

Circulating microRNAs as noninvasive diagnostic biomarkers of liver disease in children with cystic fibrosis.

OBJECTIVES: Cystic fibrosis liver disease (CFLD), resulting from progressive hepatobiliary fibrosis, causes significant morbidity and mortality in up to 20% of children with cystic fibrosis (CF). Both pathogenesis and early detection of CFLD are elusive. Current diagnostic procedures to detect early CFLD and stage fibrosis severity are inadequate. Recent studies highlight a role for microRNAs (miRNAs) in the pathogenesis of many diseases and have suggested that serum miRNAs could be used as diagnostic biomarkers. METHODS: We profiled circulating serum miRNA levels in patients with CFLD (n = 52), patients with CF without liver disease (CFnoLD, n = 30), and non-CF pediatric controls (n = 20). Extracted RNA was subjected to polymerase chain reaction (PCR) array of 84 miRNAs detectable in human serum. Seven candidate miRNAs identified were validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR), normalizing data to geNorm-determined stable reference genes, miR-19b and miR-93. RESULTS: miR-122 was significantly elevated in patients with CFLD versus patients with CFnoLD and controls (P < 0.0001). miR-25 (P = 0.0011) and miR-21 (P = 0.0133) were elevated in patients with CFnoLD versus patients with CFLD and controls. CFLD was discriminated by both miR-122 (area under the curve [AUC] 0.71, P = 0.002) and miR-25 (AUC 0.65, P = 0.026). Logistic regression combining 3 miRNAs (-122, -25, -21) was greatly predictive of detecting CFLD (AUC 0.78, P < 0.0001). A combination of 6 miRNAs (-122, -21, -25, -210, -148a, -19a) distinguished F0 from F3-F4 fibrosis (AUC 0.73, P = 0.04), and miR-210 combined with miR-22 distinguished F0 fibrosis from any fibrosis, that is, F1-F4 (AUC 0.72, P = 0.02). CONCLUSIONS: These data provide the first evidence of changes to circulating miRNA levels in CF, suggesting that serum-based miRNA analysis may complement and extend current CFLD screening strategies with potential to predict early hepatic fibrosis.

Transcriptional basis for hepatic fibrosis in cystic fibrosis-associated liver disease.

OBJECTIVES: Liver disease contributes to significant morbidity and mortality in cystic fibrosis (CF). Although all patients with CF express the defective CF transmembrane conductance regulator in cholangiocytes, many develop asymptomatic fibrosing liver disease. Only some develop cirrhosis, with pathogenesis remaining enigmatic. Available noninvasive diagnostic tools do not identify patients at risk before development of advanced fibrosis. We conducted a pilot study to identify genes associated with hepatic injury and fibrosis on liver biopsy that may help elucidate determinants of CF-associated liver disease (CFLD). METHODS: Liver tissue from children with CFLD with various stages of hepatic fibrosis was compared with pediatric controls using cDNA array analysis. Differential expression of genes of interest was then assessed relative to pediatric control liver and non-CF cholestatic disease control liver from patients with biliary atresia, using both real-time reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: cDNA array demonstrated differential expression of numerous genes associated with hepatic fibrogenesis including collagens, matrix metalloproteinases, and chemokines in CFLD versus normal controls, particularly decreased expression in tissue remodeling genes including plasminogen activator inhibitor-1 (PAI-1, up to 25-fold) and tissue inhibitor of metalloproteinase-1 (TIMP-1); this was validated by real-time reverse transcription-polymerase chain reaction (PAI-1, P = 0.004; TIMP-1, P = 0.019). No significant decrease in PAI-1 or TIMP-1 mRNA was observed in biliary atresia versus normal control. Immunohistochemistry confirmed the decreased expression of hepatic PAI-1 and TIMP-1 protein in CFLD versus both normal and biliary atresia disease controls. CONCLUSIONS: The coordinated differential expression of these genes associated with liver fibrosis provides evidence for a transcriptional basis for the pathogenesis of CFLD and provides avenues for further study. Clarifying the pathogenesis of CFLD will facilitate techniques for early, precirrhotic detection and targeted interventions.