Arie P. van den Berg

Chronic hepatitis E virus infection in liver transplant recipients

Hepatitis E virus (HEV) infection is known to run a self‐limiting course. Sporadic cases of acute hepatitis due to infection with HEV genotype 3, present in pig populations, are increasingly recognized. Zoonotic transmission seems infrequent. The entity of unexplained chronic hepatitis after liver transplantation has been recognized. Detection of HEV in 2 liver transplant recipients triggered a review of these cases. Freeze‐stored sera were available for retrospective analysis. HEV antibodies were determined. For virus detection and identification, a fragment of the gene encoding the major capsid protein (open reading frame 2) was amplified by reverse‐transcription polymerase chain reaction and sequenced to identify the genotype. Two months after liver transplantation, case A developed unexplained chronic hepatitis, which developed into cirrhosis. Retransplantation followed 7 years later, after which chronic hepatitis recurred. In retrospect, HEV RNA was present in serum 3 weeks after the first transplantation and remained present afterwards. HEV RNA was also present in retransplant liver tissue. HEV antibodies appeared late after retransplantation. Case B developed unexplained chronic hepatitis 7 years after transplantation. Retransplantation was needed 5 years later, after which no signs of hepatitis recurred. In retrospect, the period of chronic hepatitis up to the retransplantation coincided with HEV RNA in serum. In case B, antibodies developed, the viral load was much lower than in case A, and the virus seemed to be cleared after retransplantation. Genotyping in both cases revealed 2 unique strains of genotype 3. In conclusion, chronic HEV infection may develop in immunosuppressed patients, who may then serve as long‐term carriers of the virus. We hypothesize that HEV may be the cause of chronic hepatitis in liver transplant recipients. Liver Transpl 14:547–553, 2008.

Prevalence of hepatitis E virus infection in liver transplant recipients

Hepatitis E virus (HEV) infection is known to run a self‐limited course. Recently, chronic hepatitis E has been described in several immunosuppressed patients after solid organ transplantation. The prevalence of HEV infection after transplantation, however, is unknown. We studied HEV parameters [HEV RNA, HEV immunoglobulin M (IgM), and HEV immunoglobulin G (IgG) by enzyme‐linked immunosorbent assay and confirmatory immunoblotting] in a cohort of 285 adult liver transplant recipients. The most recent freeze‐stored sera were investigated, and if they were positive, a retrospective analysis was performed. Samples from 274 patients (96.1%) tested negative for all HEV parameters. This included a patient described earlier as having experienced an episode of chronic HEV hepatitis in the past. One patient was found positive for HEV RNA without HEV antibodies. She presently suffers from chronic HEV hepatitis and has also been described before. Sera from 9 patients tested positive for HEV IgG without HEV IgM or HEV RNA. Six of these 9 patients (2.1% of the total) were found to have HEV IgG antibodies in retrospect related to an HEV infection at some time pre‐transplant as they also tested positive in a pretransplant serum sample. One of these 9 patients suffered in retrospect from a chronic HEV infection with mild hepatitis between 2 and 5 years after liver transplantation on the basis of the course of HEV RNA, IgM, and IgG, aminotransferases, and liver histology. Overall, the prevalence of acquired HEV hepatitis after liver transplantation was 1% in this cohort. We conclude that liver transplant recipients have a risk for chronic HEV infection, but the prevalence is low. Liver Transpl 15:1225–1228, 2009.

Treatment of chronic hepatitis E in liver transplant recipients with pegylated interferon alpha-2b.

Hepatitis E virus (HEV) infections are known to run a self‐limiting course. Recently, chronic hepatitis E has been described in immunosuppressed patients after solid‐organ transplantation. Besides the general recommendation to lower the immunosuppressive medication in these patients, there is currently no specific treatment. We here describe the successful use of pegylated interferon alpha‐2b in the treatment of 2 liver transplant recipients who suffered a chronic HEV infection for 9 years (case A) or 9 months (case B). After 4 weeks of therapy, a 2‐log decrease (case A) and a 3‐log decrease (case B) in the viral load were observed. In case A, who received treatment for 1 year, serum viral RNA became undetectable from week 20 onward, and serum liver enzymes normalized completely. In case B, interferon was discontinued at week 16 because of a lack of a further decline in the viral load. However, 4 weeks after the cessation of therapy, viral RNA was no longer detectable in the serum, and this was probably related to a further decline in the immunosuppressive medication. Liver tests normalized completely. In both cases, no relapse has been noted so far. We conclude that pegylated interferon alpha‐2b may be useful in the treatment of chronic HEV infections in patients in whom the reduction of the immunosuppressive medication alone is not sufficient. Liver Transpl , 2010.

Interlaboratory variability in assessment of the model of end‐stage liver disease score

Background: The model of end‐stage liver disease (MELD) score is nowadays widely used to prioritize patients for liver transplantation.

Differential in vitro inhibition of thrombin generation by anticoagulant drugs in plasma from patients with cirrhosis.

Background Treatment and prevention of thrombotic complications is frequently required in patients with cirrhosis. However anticoagulant therapy is often withheld from these patients, because of the perceived bleeding diathesis. As a result of the limited clinical experience, the anticoagulant of choice for the various indications is still not known. Objectives We evaluated the in vitro effect of clinically approved anticoagulant drugs in plasma from patients with cirrhosis. Patients/Methods Thirty patients with cirrhosis and thirty healthy controls were studied. Thrombin generation assays were performed before and after addition of unfractionated heparin, low molecular weight heparin, fondaparinux, dabigatran, and rivaroxaban, to estimate anticoagulant potencies of these drugs. Results Addition of dabigatran led to a much more pronounced reduction in endogenous thrombin potential in patients compared to controls (72.6% reduction in patients vs. 12.8% reduction in controls, P<0.0001). The enhanced effect of dabigatran was proportional to the severity of disease. In contrast, only a slightly increased anticoagulant response to heparin and low molecular weight heparin and even a reduced response to fondaparinux and rivaroxaban was observed in plasma from cirrhotic patients as compared to control plasma. Conclusions The anticoagulant potency of clinically approved drugs differs substantially between patients with cirrhosis and healthy individuals. Whereas dabigatran and, to a lesser extent, heparin and low molecular weight heparin are more potent in plasma from patients with cirrhosis, fondaparinux and rivaroxaban showed a decreased anticoagulant effect. These results may imply that in addition to dose adjustments based on altered pharmacokinetics, drug-specific dose adjustments based on altered anticoagulant potency may be required in patients with cirrhosis.

Vascular events after liver transplantation: a long-term follow-up study

Long‐term follow‐up studies on the impact of vascular events (VE) and risk factors of liver transplant recipients are scarce. In this study, 311 recipients of a first isolated liver transplant who survived at least 1 year were followed up from 1979 to 2002. The median follow‐up duration was 6.2 (range1–22.7) years. Overall median survival was 18.7 [95% confidence interval (CI): 15.5–20.1] years and this was significantly lower compared with age‐ and sex‐matched controls. Eleven (21%) of the patients had a vascular cause of death and VE were the third cause of death. VE occurred later compared with other causes of death (mean 10.3 years vs. 4.5 years, P < 0.0001, 95% CI: 2.7–8.9). Systolic hypertension, systolic blood pressure, smoking, renal failure, age, hypertriglyceridemia, serum total cholesterol levels and hypercholesterolemia at the 1‐year follow‐up visit were associated with the occurrence of VE, but renal failure and age at 1 year after transplantation were the only independent risk factors for vascular death (hazard ratio 0.06, 95% CI: 0.01–0.41 and hazard ratio 1.17, 95% CI: 1.02–1.34, respectively). Finally, it was shown that the adequate treatment of hypertension was associated with a significant reduced risk of vascular death. Therefore, vascular risk factors should be treated aggressively to prevent VE in the long term.

Immune-mediated diseases in primary sclerosing cholangitis

BACKGROUND Primary sclerosing cholangitis is a chronic cholestatic liver disease. An immune aetiology is suggested by associations between PSC and inflammatory bowel disease. Data on concomitant prevalence of other immune-mediated diseases is limited. AIM To assess the prevalence of concomitant immune-mediated diseases and the impact on disease outcome in PSC. METHODS We included 241 patients and retrospectively reviewed medical charts. RESULTS Altogether 172 (71.4%) patients had concomitant immune-mediated disease, including IBD (149, 61.8%), autoimmune hepatitis (15, 6.2%) and other immune-mediated diseases (47, 19.5%). Thirty nine patients (22.7%) had more than one immune-mediated disease other than PSC. Most frequent extrahepatic non-IBD immune-mediated diseases were sarcoidosis, thyroid disease, and type I diabetes mellitus. Age at PSC diagnosis was lower in patients with IBD. In patients with other immune-mediated diseases than autoimmune hepatitis or IBD, age at PSC diagnosis was higher. Younger age at diagnosis and concomitant IBD related to longer survival till death or liver transplantation. CONCLUSIONS In a large PSC population, a high prevalence of concomitant immune-mediated diseases was found. IBD occurred more often in early-acquired PSC, and the other immune-mediated diseases more often in later-acquired PSC. No effect on outcome was found for non-IBD immune mediated disease.

Incidence, risk factors, and outcome of antithymocyte globulin treatment of steroid-resistant rejection after liver transplantation

We retrospectively analyzed the incidence and outcome of steroid-resistant rejection (SRR) during the first 6 months after OLT in 126 patients receiving triple immunosuppression. A total of 95 patients either did not experience acute rejection at all or had acute rejection that subsided without additional treatment. A total of 31 patients had biopsy-proven acute rejection that required therapy: 18 patients had acute rejection that responded to steroid therapy (steroidsensitive rejection, SSR); the remaining 13 patients had SRR and received ATG. At the onset of acute rejection, no differences in clinical, biochemical, or immunological parameters were present between patients with SSR and SRR. However, the histological grade of acute rejection in the initial biopsy was higher in patients with SRR (P=0.05). ATG treatment was effective in 10 of the 13 patients and was not associated with an increased incidence of opportunistic infections. Patient and graft survival rates at 2 years were comparable in the three groups. These data show that the incidence of SRR during the first 6 months after OLT is low, and that its treatment with ATG is both effective and well tolerated.

Infusion of DDAVP does not improve primary hemostasis in patients with cirrhosis

Cirrhosis frequently affects multiple components of hemostasis. Reversal of the coagulopathy of these patients is frequently required in case of bleeding episodes, or as prophylaxis before invasive procedures. Although 1‐deamino‐8‐D‐arginine vasopressin (DDAVP) is widely used as a pro‐hemostatic agent in patients with cirrhosis, it is unclear whether DDAVP truly enhances hemostasis in these patients. Here we investigated the hemostatic effects of a single bolus of DDAVP in patients with cirrhosis.

Decreased tissue factor pathway inhibitor (TFPI)-dependent anticoagulant capacity in patients with cirrhosis who have decreased protein S but normal TFPI plasma levels

Protein S acts as a cofactor for tissue factor pathway inhibitor (TFPI) in the down regulation of thrombin generation, and acquired and congenital protein S deficiencies are associated with a concomitant TFPI deficiency. In contrast, in patients with liver diseases, decreased protein S, but normal or increased levels of TFPI have been reported. We compared TFPI and protein S plasma levels between 26 patients with cirrhosis and 20 healthy controls and found that TFPI levels were comparable between patients (111 ± 38%) and controls (108 ± 27%), despite reduced protein S levels (74 ± 23% in patients vs. 98 ± 10% in controls). Subsequently, we quantified the activity of the TFPI‐protein S system by measuring thrombin generation in the absence and presence of neutralizing antibodies to protein S or TFPI. Ratios of peak thrombin generation in the absence and presence of these antibodies were calculated. Both the protein S and the TFPI ratios were increased in patients with cirrhosis compared to controls. Protein S ratios were (0·62 [0·08–0·93] in patients vs. 0·32 [0·20–0·54] in controls; TFPI ratios were 0·50 [0·05–0·90] in patients vs. 0·18 [0·11–0·49] in controls). Thus, although the acquired protein S deficiency in patients with cirrhosis is not associated with decreased TFPI levels, the TFPI/protein S anticoagulant system is functionally impaired.