Comparison of Plasma Exchange With Different Membrane Pore Sizes in the Treatment of Severe Viral Hepatitis

Progress in hepatitis B virus-related acute-on-chronic liver failure treatment in China: A large, multicenter, retrospective cohort study using a propensity score matching analysis

BACKGROUND

Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) has a high short-term mortality. However, the treatment progression for HBV-ACLF in China in the past decade has not been well characterized. The present study aimed to determine whether the HBV-ACLF treatment has significantly improved during the past decade.

METHODS

This study retrospectively compared short-term (28/56 days) survival rates of two different nationwide cohorts (cohort I: 2008-2011 and cohort II: 2012-2015). Eligible HBV-ACLF patients were enrolled retrospectively. Patients in the cohorts I and II were assigned either to the standard medical therapy (SMT) group (cohort I-SMT, cohort II-SMT) or artificial liver support system (ALSS) group (cohort I-ALSS, cohort II-ALSS). Propensity score matching analysis was conducted to eliminate baseline differences, and multivariate logistic regression analysis was used to explore the independent factors for 28-day survival.

RESULTS

Short-term (28/56 days) survival rates were significantly higher in the ALSS group than those in the SMT group (P < 0.05) and were higher in the cohort II than those in the cohort I (P < 0.001). After propensity score matching, short-term (28/56 days) survival rates were higher in the cohort II than those in the cohort I for both SMT (60.7% vs. 53.0%, 50.0% vs. 39.8%, P < 0.05) and ALSS (66.1% vs. 56.5%, 53.0% vs. 44.4%, P < 0.05) treatments. The 28-day survival rate was higher in patients treated with nucleos(t)ide analogs than in patients without such treatments (P = 0.046). Multivariate logistic regression analysis revealed that ALSS (OR = 0.962, 95% CI: 0.951-0.973, P = 0.038), nucleos(t)ide analogs (OR = 0.927, 95% CI: 0.871-0.983, P = 0.046), old age (OR = 1.028, 95% CI: 1.015-1.041, P < 0.001), total bilirubin (OR = 1.002, 95% CI: 1.001-1.003, P = 0.004), INR (OR = 1.569, 95% CI: 1.044-2.358, P < 0.001), COSSH-ACLF grade (OR = 2.683, 95% CI: 1.792-4.017, P < 0.001), and albumin (OR = 0.952, 95% CI: 0.924-0.982, P = 0.002) were independent factors for 28-day mortality.

CONCLUSIONS

The treatment for patients with HBV-ACLF has improved in the past decade.

Artificial Liver Support System Improves Short-Term Outcomes of Patients with HBV-Associated Acute-on-Chronic Liver Failure: A Propensity Score Analysis

Background

Hepatitis B virus-associated acute-on-chronic liver failure (HBV-ALCF) is a complicated syndrome with extremely high short-term mortality. The artificial liver support system (ALSS) may improve the liver function for patients with HBV-ACLF, but the data on its short-term outcomes are insufficient in China.

Methods

We recruited HBV-ACLF patients in this nationwide, multicenter, retrospective study. Patients with HBV-ACLF were diagnosed by the COSSH-ACLF criteria. Propensity score matching (PSM) analysis was used to generate compared pairs. The short-term (28/90 days) survival rates between the standard medical therapy (SMT) group and ALSS group were calculated using a Kaplan–Meier graph.

Result

In total, 790 patients with HBV-ACLF were included in this retrospective study; 412 patients received SMT only (SMT group), and 378 patients received SMT and ALSS treatment (ALSS group). PSM generated 310 pairs and eliminated the baseline differences between the two groups (p > 0.05 for all baseline variables). The probabilities of survival on day 28 were 65.2% (205/310) in the ALSS group and 59.0% (185/310) in the SMT group; on day 90, they were 51.0% (163/310) and 42.3% (136/310). The short-term (28/90 days) survival rates of the ALSS group were significantly higher than those of the SMT group (p=0.0452 and p=0.0187, respectively). Compared to receiving SMT alone, treatment with ALSS was associated with a significant reduction in serum bilirubin levels and the model for end-stage liver disease (MELD) scores at day 7 and day 28. Multivariate logistic regression analysis revealed that older age, high total bilirubin (T-Bil), low albumin, high ALT, high MELD scores, and high COSSH-ACLF grade were independent baseline factors associated with poor prognosis.

Conclusions

This retrospective study found that compared to SMT, the ALSS improved the short-term (28/90 days) survival rates and laboratory parameters in HBV-ACLF patients. The ALSS had a better therapeutic effect than SMT for patients with HBV-ACLF in China.

Plasma Adiponectin Levels in Acute Liver Failure Patients Treated with Plasma Filtration with Dialysis and Plasma Exchange

Plasma filtration with dialysis (PDF) is a blood purification therapy in which simple plasma exchange (PE) is performed using a selective membrane plasma separator while the dialysate flows outside of the hollow fibers. Improvement of hypoadiponectinemia is considered to be a useful therapeutic approach for ameliorating fatal conditions including cardio-metabolic and infectious disease. We investigated the effects of PDF in comparison to PE in terms of plasma adiponectin (APN) changes in patients with acute liver failure. Seventeen patients with liver failure were studied; PDF was performed 55 times and PE 14 times. Plasma APN levels increased significantly after PDF, while decreasing significantly after PE. PDF appears to be among the most useful blood purification therapies in acute liver failure cases in terms of increasing APN levels.

Acute liver failure caused by herpes simplex virus in a pregnant patient: is there a potential role for therapeutic plasma exchange?

A young woman presented with a febrile illness in the third trimester of pregnancy. Laboratory investigation revealed severe acute hepatitis with thrombocytopenia and coagulopathy. Liver injury progressed despite emergent caesarian section and delivery of a healthy infant. Therefore, therapeutic plasma exchange (TPE) was performed on three consecutive days post-partum for a presumed diagnosis of acute liver failure (ALF) associated with pregnancy due to hemolysis, elevated liver enzymes, and low platelets (HELLP) or acute fatty liver of pregnancy (AFLP). Treatment with TPE was followed by biochemical and clinical improvement but during her recovery herpes simplex virus type 2 (HSV-2) infection was diagnosed serologically and confirmed histologically. Changes in the immune system during pregnancy make pregnant patients more susceptible to acute HSV hepatitis, HSV-related ALF, and death. The disease is characterized by massive hepatic inflammation with hepatocyte necrosis, mediated by both direct viral cytotoxicity and the innate humoral immune response. TPE may have a therapeutic role in acute inflammatory disorders such as HSV hepatitis by reducing viral load and attenuating systemic inflammation and liver cell injury. Further investigation is needed to clarify this potential effect. The roles of vigilance, clinical suspicion, and currently accepted therapies are emphasized.

Extracorporeal liver perfusion system for artificial liver support across a membrane

BACKGROUND

An extracorporeal porcine liver perfusion (ECPLP) system circumvents the limitations of hepatocyte based bio-artificial liver, but its clinical application has been limited so far due to the potential risk of transmission of porcine endogenous retroviruses. The aim of this study was to develop an ECPLP model that can provide artificial hepatic support across a semi-permeable membrane, which has the potential to block porcine viruses due to its pore size.

MATERIALS AND METHODS

Livers from white landrace pigs were perfused with normothermic oxygenated blood using Medtronic BP560 centrifugal pump (Medtronic, Inc., Minneapolis. MN). This ECPLP system was used to support a "surrogate" patient across the filter Evaclio-EC4A. Function of liver was measured by indocyanine green retention at 15 min (ICGR15). Clearance of galactose, ammonia, and para-aminobenzoic acid infused into the "surrogate" patient circulation was calculated to assess liver support across the membrane. The study was designed as test (n = 15) versus control (n = 5), with control experiments having no liver in the circuit.

RESULTS

For the test experiments, we perfused 15 livers with mean hepatic artery pressure of 87 mm Hg and flows of 1.2 L/min. ICGR15 in test experiments was 11%. Ammonia clearance was 945 mg/min/kg, galactose metabolic rate was 111.7 mg/min/Kg, and the hippurate ratio was 91% in the test. In contrast, the control experiments did not show any significant change in the concentration of any of these compounds.

CONCLUSION

Our ECPLP model was able to provide hepatic support in an experimental setting across a hollow fiber filter. Further work on an anhepatic animal is needed prior to application in human trials.

Multicenter study of plasma diafiltration in patients with acute liver failure

Plasma diafiltration (PDF) is a blood purification therapy in which simple plasma exchange (PE) is performed using a selective membrane plasma separator while the dialysate flows outside the hollow fibers. A prospective, multicenter study was undertaken to evaluate the changes in bilirubin, IL-18, and cystatin C, as well as the 28-day and 90-day survival rates, with the use of PDF according to the level of severity as measured by the Model for End-Stage Liver Disease (MELD) score. Twenty-one patients with liver failure were studied: 10 patients had fulminant hepatitis and PDF therapies were performed 28 times; 11 had acute liver failure with the therapy performed 96 times. Levels of total bilirubin, IL-18, and cystatin C decreased significantly after treatment. The 28-day survival rate was 70.0% and that at 90 days was 16.7%. According to the severity of the MELD score, each of the results compared well with the use of Molecular Adsorbent Recirculating System or Prometheus therapy. In conclusion, PDF appears to be one of the most useful blood purification therapies for use in cases of acute liver failure in terms of medical economics and the removal of water-soluble and albumin-bound toxins.

Selective albumin exchange: a novel and simple method to remove bilirubin

PURPOSE

Owing to its non-selectivity, plasma exchange has limited use in the treatment of patients with hepatic failure, although it is effective in removal of protein-bound toxins. This study reports a novel way to perform selective albumin exchange (SAE) by using a secondary plasma separator and aims to study its depurative capacity in the removal of bilirubin.

METHOD

In ex vivo experiments, the sieving coefficients (SCs) of plasma proteins for two secondary plasma separators, EC20W and EC30W (Asahi Medical, Tokyo, Japan), were measured. The EC20W membrane was chosen for use in clinical treatment because of its higher selectivity in separating albumin from plasma than the EC30W. The SCs of albumin, immunoglobumin G, A and M (IgG, IgA, IgM) for the EC20W were 0.3+/-0.021, 0.017+/-0.012, and 0, respectively. Five inpatients with plasma total bilirubin (TB) more than 200 micromol/L were enrolled in the present study and received a total of 10 SAE therapy sessions. Each session lasted 10 hours. SAE using the EC20W was conducted, making it similar to post-dilution continuous veno-venous hemofiltration (CVVH), with a filtrate rate of 2000 ml/h. Replacement fluid was composed by adding human albumin into conventional CVVH replacement fluid, with a final albumin concentration of 0.6%. During each treatment, the parameters of plasma and filtrate TB, direct bilirubin (DB), indirect bilirubin (IDB), and proteins were dynamically monitored. Hemostasis parameters were measured before and after sessions.

RESULTS

The reduction ratio of plasma TB, DB, and IDB after a single session was 29.1+/-3.0%, 31.3+/-4.5%, and 18.7+/-10.2%, respectively. The clearance of TB at initiation was 11.1+/-1.3 mL/min and declined to 4.4+/-0.5 ml/min at the end (p<0.01). This decline was accompanied by a reduction in albumin SC from 0.3+/-0.021 to 0.13+/-0.05. The molar ratio of bilirubin to albumin in filtrate was comparable to that in plasma. After a single treatment, plasma protein concentration including total protein, albumin, IgA and IgM remained unaffected, except for globulin and IgG, which were reduced by 11.5+/-7.8% and 11.1+/-2.3%, respectively. An improvement in hemostasis parameters, including plasma fibrinogen, prothrombase time and INR, was found after treatment. No obvious side effects were reported during any of the sessions.

CONCLUSION

Selective albumin exchange is a simple and effective method to remove bilirubin. However, further studies are required to verify its effects on clinical outcome.