Prognostic Markers in Pediatric Acute Liver Failure

Introduction

Acute liver failure (ALF), although rare in children, is a complex progressive pathology, with multisystem involvement and high mortality. Isolated variables or those included in prognostic scores have been studied, to optimize organ allocation. However, its validation is challenging. This study aimed to assess the accuracy of several biomarkers and scores as predictors of prognosis in pediatric ALF (PALF).

Methods

An observational study with retrospective data collection, including all cases of ALF, was defined according to the criteria of the Pediatric Acute Liver Failure Study Group, admitted to a pediatric intensive care unit (PICU) for 28 years. Two groups were defined: spontaneous recovery (SR) and non-SR (NSR) - submitted to liver transplantation (LT) or death at PICU discharge.

Results

Fifty-nine patients were included, with a median age of 24 months, and 54% were female. The most frequent etiologies were metabolic (25.4%) and infectious (18.6%); 32.2% were undetermined. SR occurred in 21 patients (35.6%). In NSR group (N = 38, 64.4%), 25 required LT (42.4%) and 19 died (32.2%), 6 (15.7%) of whom after LT. The accuracy to predict NSR was acceptable for lactate at admission (AUC 0.72; 95% CI: 0.57-0.86; p = 0.006), ammonia peak (AUC 0.72; 95% CI: 0.58-0.86; p = 0.006), and INR peak (AUC 0.70; 95% CI: 0.56-0.85; p = 0.01). The cut-off value for lactate at admission was 1.95 mmol/L (sensitivity 78.4% and specificity 61.9%), ammonia peak was 64 μmol/L (sensitivity 100% and specificity 38.1%), and INR peak was 4.8 (sensitivity 61.1% and specificity 76.2%). Lactate on admission was shown to be an independent predictor of NSR on logistic regression model. Two prognostic scores had acceptable discrimination for NSR, LIU (AUC 0.73; 95% CI: 0.59-0.87; p = 0.004) and PRISM (AUC 0.71; 95% CI: 0.56-0.86; p = 0.03). In our study, the PALF delta score (PALF-ds) had lower discrimination capacity (AUC 0.63; 95% CI: 0.47-0.78; p = 0.11).

Conclusions

The lactate at admission, an easily obtained parameter, had a similar capacity than the more complex scores, LIU and PRISM, to predict NSR. The prognostic value in our population of the promising dynamic score, PALF-ds, was lower than expected.

Pediatric acute liver failure: Current perspective in etiology and management

Pediatric acute liver failure (PALF) is a catastrophic clinical condition with very high morbidity and mortality without early detection and intervention. It is characterized by the acute onset of massive hepatocellular injury that releases circulating inflammatory mediators, resulting in metabolic disturbances, coagulopathy, hepatic encephalopathy and multi-organ failure. The etiological spectrum is dominated by hepatotropic viruses, drug-induced liver injury, metabolic and genetic disorders and immune-mediated diseases. Unlike adults, indeterminate causes for acute liver failure constitute a considerable proportion of cases of acute liver failure in children in the west. The heterogeneity of age and etiology in PALF has led to difficulties in developing prognostic scoring. The recent guidelines emphasize prompt identification of PALF, age-appropriate evaluation for hepatic encephalopathy and laboratory evaluation with careful monitoring. Current therapy focuses on supporting the failing liver and other organs, pending either spontaneous recovery or liver transplantation. Targeted therapy is available for a select group of etiologies. Liver transplantation can be lifesaving and a plan for the same should be organized, whenever indicated. The aim of this review is to define PALF, understand its etiopathogenesis, address the challenges encountered during the management and update the latest advances in liver transplantation and non-transplant treatment options in PALF.

Prognostic markers in hepatitis A-related pediatric acute liver failure and validation of the Peds-hepatitis A virus prognostic model

OBJECTIVES

Hepatitis A virus (HAV) is the commonest cause for pediatric acute liver failure (PALF) in India. The objective of the study was to identify the predictors of mortality and to evaluate the utility of Peds-HAV model in a cohort of non-LT HAV-PALF.

METHODS

The study included HAV-related PALF from two non-transplant centers. The predictors of outcome were identified by univariate analysis followed by Cox regression analysis. The prognostic accuracy of Peds-HAV model, King's College Hospital (KCH) criteria and pediatric end-stage liver disease score (PELD) were evaluated.

RESULTS

As many as 140 children with PALF were included, of whom 96 (68.6%) children had HAV-PALF. On Cox regression analysis, international normalized ratio (INR) (p < 0.001), jaundice to encephalopathy (JE) interval (p < 0.001) and hepatic encephalopathy (HE) grade 3/4 (p = 0.01) were independent predictors of mortality. The mortality rates were 0% (0/42), 14.3% (3/21), 60% (9/15) and 94.4% (17/18) when none, 1, 2 or 3 criteria of the Peds-HAV were met, respectively. Peds-HAV model at a listing cut-off of  ≥ 2 criteria predicted death with 89.7% sensitivity and 89.6% specificity. In contrast, KCH criteria had a lower sensitivity of 62.1%. PELD score had a sensitivity of 89.7% and specificity of 85.1% at a cut-off of 30. The overall prognostic accuracy of Peds-HAV model (89.6%) was higher than those of KCH (83.3%) and PELD (86.5%).

CONCLUSION

INR, HE grade and JE interval were independent predictors of mortality. The study provides an external validation of Peds-HAV model as a prognostic score in HAV-PALF.

CLINICAL TRIAL REGISTRY NUMBER

Not applicable as this is a retrospective study.

Dynamic risk score modeling for multiple longitudinal risk factors and survival

Modeling disease risk and survival using longitudinal risk factor trajectories is of interest in various clinical scenarios. The capacity to build a prognostic model using the trajectories of multiple longitudinal risk factors, in the presence of potential dependent censoring, would enable more informed, personalized decision making. A dynamic risk score modeling framework is proposed for multiple longitudinal risk factors and survival in the presence of dependent censoring, where both events depend on participants' post-baseline clinical progression and form a competing risks structure. The model requires relatively few random effects regardless of the number of longitudinal risk factors and can therefore accommodate multiple longitudinal risk factors in a parsimonious manner. The proposed method performed satisfactorily in extensive simulation studies. It is further applied to the motivating registry study on pediatric acute liver failure to model death using the trajectories of multiple clinical and biochemical markers. Once established, the model yields an easily calculable longitudinal risk score that can be used for disease monitoring among future patients.

Live donor liver transplantation for pediatric acute liver failure: challenges and outcomes

OBJECTIVE

This study aimed at studying the challenges and outcomes of live-donor liver transplantation (LDLT) for pediatric acute liver failure (PALF).

STUDY DESIGN

A total of 315 patients with PALF were treated over a period of 11 years. 42 underwent LT (41 LDLT and one DDLT), constituting 38% (41/110) of all pediatric transplants during this duration. The outcomes of LDLT for PALF were analyzed.

RESULTS

All the 41 children who underwent LT met the Kings College criteria (KCC). The etiology was indeterminate in 46.3% (n = 19) children. 75.6% (n = 31) were on mechanical ventilation for grade 3/4 hepatic encephalopathy. There was presence of cerebral edema on a computed tomography scan of the brain in 50% of the children. One-third of our children required hemodynamic support with vasopressors. Systemic inflammatory response syndrome and sepsis were observed in 46.3% and 41.4% of patients, respectively. Post-LDLT 1- and 5-yr patient and graft survival were 75.6% and 70.9%, respectively. The survival in children satisfying KCC but did not undergo LT was 24% (38/161). Vascular and biliary complication rates were 2.4% and 4.8%, respectively. No graft loss occurred because of acute rejection. In multivariate analysis, pre-LT culture positivity and cerebral edema, persistence of brain edema after transplantation, and resultant pulmonary complications were significantly associated with post-LT death. Thirteen (32%) children who underwent plasmapheresis prior to LT had better post-LT neurological recovery, as evidenced by early extubation.

CONCLUSION

LDLT for PALF is lifesaving and provides a unique opportunity to time transplantation. Good long-term survival can be achieved, despite the majority of patients presenting late for transplantation. Early referral and better selection can save more lives through timely transplantation.

Etiology, outcome and prognostic indicators of acute liver failure in Asian children

OBJECTIVE

Outcome of pediatric acute liver failure (PALF) in countries with limited availability of LT is not well described. We evaluated the outcome and prognostic indicators of PALF in Malaysia where emergency LT for ALF is limited.

METHODS

In this retrospective review on children < 18 years with PALF, we compared clinical and laboratory parameters between survival after supportive treatment and after LT or succumbed without LT. The predictive values of Liver Injury Unit (LIU; peak laboratory values for international normalized ratio [INR], ammonia, total bilirubin) and upon admission (aLIU) on outcome of PALF was evaluated using receiver operator characteristic (ROC) curves.

RESULTS

Of 77 children (39 males [51%]; median age 2.8 years) with PALF, the overall survival was 55% (n = 42); 52% (n = 40) survived with supportive management, 2.6% (n = 2) after LT. As compared to children who survived without LT, children who had LT/died had lower hemoglobin, aspartate transferase, γ-glutamyl transpeptidase (GGT), and higher serum bilirubin, alkaline phosphatase, ammonia, and serum sodium (p < 0.05). On multivariate analysis, significant independent predictor for death or LT were peak bilirubin > 452 μmol/L and peak GGT < 96 IU/L. The C-index of LIU and aLIU score were 0.79 and 0.68, respectively, indicating that LIU score was a good model in predicting outcome of PALF.

CONCLUSIONS

Overall survival of PALF remained poor. High peak bilirubin and low GGT predict poor outcome of PALF. LIU score is a good model in predicting outcome of PALF and maybe useful in selecting children for emergency LT.

An Update on Pediatric Acute Liver Failure: Emerging Understanding of the Impact of Immune Dysregulation and Novel Opportunities for Intervention

Pediatric acute liver failure (PALF) is a complex, unpredictable, often rapidly progressive, potentially devastating clinical syndrome that occurs in infants, children, and adolescents without pre-existing liver disease. PALF is characterized by acute onset of hepatocellular injury and liver-based coagulopathy, frequently accompanied by hepatic encephalopathy. Etiologies include drug and toxin exposures, metabolic and genetic disorders, infections, and immune-mediated disease. PALF management primarily involves early contact with and consideration of transfer to a pediatric liver transplant center and intensive supportive multidisciplinary clinical care, with targeted therapies available for a subset of causes. Outcomes include survival with native liver, death, and liver transplantation. Efforts to develop reliable clinical prognostic tools to predict PALF outcomes early in the course of disease have not yet been fulfilled, and the possibility remains that some transplanted PALF patients might have survived without transplantation.

Artificial liver support system in pediatric acute liver failure due to mushroom poisoning: Case series

Pediatric acute liver failure (PALF) due to mushroom poisoning is a rare and life-threatening disease. There is no specific treatment. Plasma exchange (PE) is often used as a bridge to the regeneration of the liver or transplantation. However, PE is limited due to an inadequate plasma supply and transfusion-related risks. The double plasma molecular adsorption system (DPMAS) can adsorb toxins, including bilirubin and inflammatory mediators. However, the DPMAS cannot improve coagulation disorders. Combining PE and the DPMAS could compensate for the shortcomings of the two techniques. A previous study showed that the combination might be more effective than using PE or the DPMAS alone in patients with mild acute-on-chronic liver failure. To the best of our knowledge, few studies combined PE and the DPMAS for the treatment of PALF due to mushroom poisoning. Here, we specifically describe our experience with PE and the DPMAS in PALF. In conclusion, our study shows that the DPMAS and PE are safe and effective in reducing the bilirubin level and improving blood coagulation in PALF due to mushroom poisoning as a bridge to transplantation or recovery.

Bispectral Index™ variation during living donor liver transplantation in a child with hepatic encephalopathy: a case report

Background

It is unclear whether perioperative Bispectral Index™ (BIS) monitoring in pediatric cases with acute liver failure (ALF) is effective for evaluation of neurological function. We describe a pediatric patient with hepatic encephalopathy (HE) in whom the BIS value increased from low levels to the normal range during liver transplantation (LT).

Case presentation

Electroencephalography in a 6-year-old comatose girl diagnosed with ALF and HE who was unresponsive to pain and auditory stimuli revealed continuous slow waves, and hence, emergency LT was performed. Intraoperatively, BIS values remained low until reperfusion. However, BIS value variability increased after reperfusion. She was subsequently discharged without any neurological sequelae.

Conclusions

Low BIS values were considered to reflect the severity of HE. It is possible that improvement of the BIS value and waveform was a reflection of graft function. BIS monitoring might be a good indicator of neurological recovery after LT.

[Etiological analysis and short-term efficacy evaluation of acute liver failure in children]

Objective: To explore etiology, optimize the search direction of etiology, and short-term efficacy evaluation of acute liver failure in children. Methods: Children with acute liver failure who were diagnosed in the First Affiliated Hospital of Zhengzhou University from November 2011 to November 2019 were collected. Gender difference, age, living environment, etiological factors on the seasonal onset and different etiological profile of short-term prognosis were statistically analyzed. Chi-square test or Fisher's exact probability method was used to compare the rate and the constituent ratio between groups. Results: Among the 236 cases, 114 (48.31%) had unknown etiology and 122 (51.69%) had definite etiology. In the definite etiology group, 38 (16.10%), 27 (11.44%), 22 (9.32%), 15 (6.36%), 17 (7.20%), and 3 (1.27%) cases were related to drugs/toxicants, infection, congenital/vascular/biliary diseases, genetic metabolic diseases, tumor-related, and autoimmune diseases. In addition, the overall etiological distribution did not change statistically with factors such as gender, age, and seasonal onset (P > 0.05), while the difference in different living environments was statistically significant (P < 0.05). Different initial-diagnosed departments had different etiological rates, with liver transplantation department being the highest (78.26%), and pediatrics department the lowest (26.09%). In 122 children with definite etiology, there was no significant difference in gender ratio between the different etiology groups (P>0.05), but there were significant differences in age, living environment and seasonal onset (P < 0.05). Among them, congenital development/vascular/biliary tract and infectivity were the main factors in children < 3 years old, and drug/toxin-related factors were the main factors in children > 3 years old. Most of the rural children had drug/toxin and infection-related etiology, while most of the urban children had tumor and drug/toxin-related etiology. In summer and autumn, drug/toxicant correlation was dominant, while in winter and spring, infection correlation was dominant. In the unknown etiology group, the clinical cure + improvement rate between the medical treatment group and the surgical treatment group was not statistically significant (37.50% vs. 20.00%, P > 0.05), while in the definite etiology group, the above differences were statistically significant (43.96% vs. 83.87%, P < 0.05). Among the different etiology groups, the congenital/vascular/biliary group had the best short-term efficacy (72.72%, 16/22), followed by the drug/toxicity-related group (60.53%, 23/38), and the tumor-related group had the worst (23.53%, 4/17). Conclusion: The definite etiology of acute liver failure in about half of children is still vague. The population distribution of children with definite etiology is related to age, living environment and season, but not to gender. However, the different ages, different living environments, and different seasonal onsets have definite etiology, and the short-term clinical efficacy of the treatment is significantly improved after the definite etiology is identified.

Timing of liver transplantation for pediatric acute liver failure due to mushroom poisoning: a case report and literature review

Background

Pediatric acute liver failure is a rare, life-threatening illness. Mushroom poisoning is a rare etiology. For patients with irreversible pediatric acute liver failure, liver transplantation is the ultimate lifesaving therapy. However, it is difficult to determine the optimal timing of transplantation. Here, we present a case of pediatric acute liver failure due to mushroom poisoning in northeastern China. He was treated with liver transplantation and recovered. To our knowledge, there are few reports about liver transplantation for pediatric acute liver failure caused by mushroom poisoning in mainland China.

Case presentation

The patient was a previously healthy 9-year-old boy who gradually developed nausea, vomiting, jaundice and coma within 5 days after ingesting mushrooms. He was diagnosed with mushroom poisoning and acute liver failure. He was treated with conservative care but still deteriorated. On the 7th day after poisoning, he underwent LT due to grade IV hepatic encephalopathy. Twenty days later, he recovered and was discharged. A review of the literature revealed that the specific criteria and optimal timing of transplantation remain to be determined.

Conclusions

Patients with pediatric acute liver failure should be transferred to a center with a transplant unit early. Once conservative treatment fails, liver transplantation should be performed.