Level of γ-glutamyltransferase in 2-Year-old Children With Biliary Atresia Associates With Progression of Portal Hypertension

Measurement of Gamma Glutamyl Transferase to Determine Risk of Liver Transplantation or Death in Patients With Primary Biliary Cholangitis

BACKGROUND & AIMS

Gamma-glutamyltransferase (GGT) is a serum marker of cholestasis. We investigated whether serum level of GGT is a prognostic marker for patients with primary biliary cholangitis (PBC).

METHODS

We analyzed data from patients with PBC from the Global PBC Study Group, comprising 14 centers in Europe and North America. We obtained measurements of serum GGT at baseline and time points after treatment. We used Cox model hazard ratios to evaluate the association between GGT and clinical outcomes, including liver transplantation and liver-related death.

RESULTS

Of the 2129 patients included in our analysis, 281 (13%) had a liver-related clinical endpoint. Mean age at diagnosis was 53 years and 91% of patients were female patients. We found a correlation between serum levels of GGT and alkaline phosphatase (ALP) (r = 0.71). Based on data collected at baseline and yearly for up to 5 years, higher serum levels of GGT were associated with lower hazard for transplant-free survival. Serum level of GGT at 12 months after treatment higher than 3.2-fold the upper limit of normal (ULN) identified patients who required liver transplantation or with liver-related death at 10 years with an area under the receiver operating characteristic curve of 0.70. The risk of liver transplantation or liver-related death in patients with serum level of GGT above 3.2-fold the ULN, despite level of ALP lower than 1.5-fold the ULN, was higher compared to patients with level of GGT lower than 3.2-fold the ULN and level of ALP lower than 1.5-fold the ULN (P < .05). Including information on level of GGT increased the prognostic value of the Globe score.

CONCLUSIONS

Serum level of GGT can be used to identify patients with PBC at risk for liver transplantation or death, and increase the prognostic value of ALP measurement. Our findings support the use of GGT as primary clinical endpoint in clinical trials. In patients with low serum level of ALP, a high level of GGT identifies those who might require treatment of metabolic disorders or PBC treatment escalation.

Modeling Outcomes in Children With Biliary Atresia With Native Liver After 2 Years of Age

Approximately 50% of infants with biliary atresia (BA) undergoing Kasai portoenterostomy show survival with native liver (SNL) at age 2 years. Predictors of disease progression after age 2 years are unknown, despite estimates of 20%-30% undergoing liver transplant (LT) between age 2 and 18 years. We sought to address this knowledge gap by developing prognostic models in participants of the multicenter prospective National Institutes of Health-supported Childhood Liver Disease Research Network. We extracted 14 clinical and biochemical variables at age 2 years to develop two models for future outcomes: 1) LT or death (LTD) and 2) first sentinel event (SE), either new onset ascites, hepatopulmonary syndrome (HPS), or gastrointestinal (GI) bleed. A total of 240 participants, enrolled between 2004 and 2017, were followed until a median age of 5.1 years (range, 2.0-13.3 years). Of these participants, 38 underwent LT (n = 37) or death (n = 1); cumulative incidence, 23.7% (95% confidence interval [CI], 16.2%-32.0%). Twenty-seven experienced either new-onset ascites (n = 13), HPS (n = 1), or GI bleed (n = 14). One participant had ascites and GI bleed concurrently; cumulative incidence, 21.5% (95% CI, 14.2%-29.8%) by age 10 years. The Cox proportional hazard model predicted risk of LTD, using total bilirubin, albumin, platelet count, and history of either ascites or cholangitis (BA LTD model), with a C-index of 0.88 (range, 0.86-0.89). A cause-specific hazard competing risk model predicted SE using platelet count and gamma glutamyltransferase levels (BA SE model) with a C-index of 0.81 (range, 0.80-0.84). Internal model validity was assessed using Harrell's C-index with cross-validation. Conclusion: Stratification using these models identified risk of poor outcomes in patients with BA SNL after age 2 years. The models may identify those who would benefit from enhanced clinical surveillance and prioritization in clinical trials.

Normal Gamma Glutamyl Transferase Levels at Presentation Predict Poor Outcome in Biliary Atresia

OBJECTIVES

Gamma-glutamyl transferase levels (GGT) are typically elevated in biliary atresia (BA), but normal GGT levels have been observed. This cohort of "normal GGT" BA has neither been described nor has the prognostic value of GGT level on outcomes in BA. We aimed to describe outcomes of a single-centre Australian cohort of infants with BA and assess the impact of GGT level at presentation on outcomes in BA.

METHODS

Infants diagnosed with BA between 1991 and 2017 were retrospectively analysed. Outcomes were defined as survival with native liver, liver transplantation (LT), and death. Patients were categorized into normal (<200I U/L) or high GGT groups based on a mean of 3 consecutive GGT values done before Kasai portoenterostomy (KPE). Baseline parameters, age at surgery, clearance of jaundice (COJ), and outcomes were compared between the 2 groups.

RESULTS

One hundred thirteen infants underwent KPE at median 61 (30-149) days. At a median follow-up of 14.2 (0.9-26.3) years, 35% (39/113) patients were surviving with native liver, 55% (62/113) underwent LT and 11% (12/113) died pretransplant. 12.3% (14/113) patients had normal GGT. Age at KPE and time to COJ were similar between normal and high GGT groups. Normal GGT group had shorter time from KPE to LT (11 vs 18 months, P = 0.02), underwent LT at a younger age (14 vs 20 months, P = 0.04), and had poorer transplant-free survival (P = 0.04) than high GGT group.

CONCLUSIONS

12.3% of infants with BA had normal GGT levels at diagnosis. Low GGT levels at presentation in BA was associated with a poorer outcome.

Racial disparities in presentation and outcomes of paediatric autoimmune hepatitis

BACKGROUND & AIMS

Most studies on autoimmune hepatitis (AIH) in children are in predominantly Caucasian cohorts. Paediatric AIH in African Americans (AA) is understudied, with a dearth of clinical predictors of outcome, often leading to serious complications and even mortality. The aim of the study was to define disease presentation, progression, response to therapy and outcomes in paediatric AIH in a well-defined, large, single centre, demographically diverse population.

METHODS

We conducted a review of patients with AIH who were followed at this tertiary liver transplant centre. Clinical and laboratory covariates were assessed with regard to disease presentation, progression and outcomes in AA vs Non-AA children.

RESULTS

African Americans patients constituted 42% of this cohort. At 1-year follow-up, AA children were receiving significantly higher doses of steroids compared to non-AA. More AA presented with end-stage liver disease (ESLD) with high immunoglobulin G and GGT:platelet ratio. After adjusting for other risk factor variables like gender, age at presentation and ESLD, AA children were at 4.5 times higher risk for significant outcome liver transplant/death within the first 12 months of presentation. Post-transplant, recurrent AIH was seen in 50% of AA vs 8% in non-AA.

CONCLUSIONS

African American patients with AIH are more likely to present with ESLD and have an increased early risk for transplantation with high likelihood of disease recurrence post-transplantation. Studies are needed to delineate factors such as inherent biology, genetics and access to care. Early referral and tailored immunosuppressive regimens are required for AA patients with AIH.

Gamma Glutamyltransferase Reduction Is Associated With Favorable Outcomes in Pediatric Primary Sclerosing Cholangitis

Adverse clinical events in primary sclerosing cholangitis (PSC) happen too slowly to capture during clinical trials. Surrogate endpoints are needed, but no such validated endpoints exist for children with PSC. We evaluated the association between gamma glutamyltransferase (GGT) reduction and long-term outcomes in pediatric PSC patients. We evaluated GGT normalization (< 50 IU/L) at 1 year among a multicenter cohort of children with PSC who did or did not receive treatment with ursodeoxycholic acid (UDCA). We compared rates of event-free survival (no portal hypertensive or biliary complications, cholangiocarcinoma, liver transplantation, or liver-related death) at 5 years. Of the 287 children, mean age of 11.4 years old, UDCA was used in 81% at a mean dose of 17 mg/kg/day. Treated and untreated groups had similar GGT at diagnosis (314 versus 300, P= not significant [NS]). The mean GGT was reduced at 1 year in both groups, with lower values seen in treated (versus untreated) patients (99 versus 175, P= 0.002), but 5-year event-free survival was similar (74% versus 77%, P= NS). In patients with GGT normalization (versus no normalization) by 1 year, regardless of UDCA treatment status, 5-year event-free survival was better (91% versus 67%, P< 0.001). Similarly, larger reduction in GGT over 1 year (> 75% versus < 25% reduction) was also associated with improved outcome (5-year event-free survival 88% versus 61%, P= 0.005). Conclusion:A GGT < 50 and/or GGT reduction of > 75% by 1 year after PSC diagnosis predicts favorable 5-year outcomes in children. GGT has promise as a potential surrogate endpoint in future clinical trials for pediatric PSC.