Percutaneous liver biopsy complications in patients with chronic renal failure

Aminotransferase-to-platelet ratio index and Fibrosis-4 index score predict hepatic fibrosis evaluated by transient hepatic elastography in hepatitis C virus-infected hemodialysis patients

OBJECTIVE

This study aimed to evaluate the performance of aminotransferase-to-platelet ratio index (APRI) and Fibrosis-4 index (FIB-4) in chronic kidney disease stage 5D HCV-infected patients compared to transient hepatic elastography (TE) as the gold standard.

METHODS

Hemodialysis HCV-infected patients submitted to TE (FibroScan, Echosens, Paris, France) had APRI and FIB-4 calculated. Based on the best area under receiver operating characteristic curve (AUROC) for significant fibrosis and cirrhosis, APRI and FIB-4 cutoffs were determined and their performances were compared.

RESULTS

Seventy patients were included. Both APRI and FIB-4 showed good performance for identifying significant fibrosis [AUROC = 0.73, 95% confidence interval (CI) 0.61-0.83 and 0.79, 95% CI 0.68-0.88; P < 0.05] and cirrhosis [AUROC = 0.82, 95% CI 0.71-0.90 and 0.85, 95% CI 0.75-0.93; P < 0.05]. APRI ≤ 0.25 excluded significant fibrosis with negative predictive value (NPV) of 81.8% and APRI > 0.61 confirmed it with a positive predictive value (PPV) of 81.8%. Similarly, NPV for FIB-4 ≤ 0.60 regarding significant fibrosis was 90.9%. NPV for cirrhosis for APRI ≤ 0.42 or FIB-4 ≤ 1.40 was 97%. However, APRI > 0.73 or FIB-4 > 2.22 showed a modest PPV of 60 and 70% to confirm cirrhosis, respectively.

CONCLUSION

APRI and FIB-4 are simple, non-expensive scoring systems with good accuracy to assess fibrosis in HCV-infected hemodialysis patients, mainly excluding both significant fibrosis or cirrhosis and may be an alternative to TE in the evaluation of this population.

Impact of hemodialysis on liver stiffness measured with real-time two-dimensional shear wave elastography

BACKGROUND AND AIMS

The impact of hemodialysis on liver stiffness is still unclear. The aim of the study was to assess liver fibrosis by real-time two-dimensional shear wave elastography (RT 2D-SWE) and to quantify the influence of net fluid withdrawal on liver stiffness during one hemodialysis session. The second aim was to investigate the influence of systolic blood pressure and time spent on dialysis (in years) on liver stiffness measurements.

METHODS

This before/after hemodialysis (HD) study in a group of end stage renal disease (ESRD) patients was carried out with patients on regular HD. Measurements of liver stiffness were done using RT 2D-SWE directly before and after a hemodialysis session.

RESULTS

In this study 27 patients with mean age 69.4 ± 14.75 years were included. Mean net fluid withdrawal volume per session was 2874.07 ± 778.35 ml. Mean pre-HD and post-HD liver stiffness measurements were 8.15 kPa (95% confidence interval, CI 7.61-8.68) and 6.70 kPa (95% CI 6.10-7.30 kPa), respectively. Mean liver stiffness reduction was 1.448 ± 1.14 kPa. The amount of fluid removed correlated with the decline in liver stiffness values after HD (ρ = 0.523, P = 0.003). There was a positive but statistically not significant correlation between time spent in HD and liver stiffness (ρ = 0.151, P = 0.623) CONCLUSION: Liver stiffness significantly declined after one session of HD. The change in liver stiffness was strongly correlated with the amount of net fluid withdrawal. Random liver stiffness measurements (LSM) by RT 2D-SWE does not precisely show the degree of fibrosis, Furthermore, it is presumed that postdialysis liver stiffness values likely reflect the real degree of liver fibrosis.

Diagnostic Accuracy of Aspartate Aminotransferase to Platelet Ratio Index and Fibrosis 4 Scores in Predicting Advanced Liver Fibrosis in Patients with End-stage Renal Disease and Chronic Viral Hepatitis: Experience from Pakistan

Objectives

The aim was to assess the diagnostic accuracy of APRI and FIB-4 in assessing the stage of liver fibrosis in end stage renal disease (ESRD) patients with chronic viral hepatitis and to compare the two tests with standard tru-cut liver biopsy.

Material and Methods

The study was conducted at Sindh Institute of Urology and Transplantation Karachi (SIUT) from May 2010 to May 2014. All ESRD patients, being considered as candidates for renal transplantation and in whom liver biopsy was performed were included. Fibrosis stage was assessed on liver biopsy using Ishak scoring system. The serum transaminases and platelet counts were used to calculate APRI and FIB-4 scores.

Results

Out of 109 patients, hepatitis C and B virus infections were present in 104 (95.4%) and 3(2.8%), respectively, while 2 (1.8%) patients had both infections. The mean Ishak fibrosis score was 1.95 ± 2. Advanced fibrosis was noted in 37 (34%) patients. Univariate analysis showed that advanced liver fibrosis was associated with lower platelets counts (P=0.001) and higher aspartate aminotransferase (AST) (P=0.001), alanine aminotransferase (ALT) (P=0.022), APRI score (P=0.001) and FIB-4 score (P=0.001). On logistic regression analysis, only APRI score (P < 0.001) was found to be the independent variable associated with advanced liver fibrosis. APRI score cutoff ≥1 indicating advanced fibrosis showed sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 91.9%, 90.3%, 82.9%, 95.6%, respectively with area under the curve (AUC) of 0.97. Similarly, a FIB-4 score cutoff ≥1.1 had sensitivity, specificity, PPV and NPV of 70.27%, 66.67%, 52% and 81.36%, respectively with AUC of 0.74.

Conclusion

APRI is more accurate noninvasive test for assessing advanced liver fibrosis in ESRD patients as compared to FIB-4. It can be used to obviate the need for liver biopsy in this high risk population.

Can aminotransferase-to-platelet ratio index and other non-invasive markers effectively reduce liver biopsies for renal transplant evaluation of hepatitis C virus-positive patients?

BACKGROUND

Advanced fibrosis or cirrhosis is still regarded as a contraindication for kidney transplantation alone by most centers. The value of aminotransferase to platelet ratio index (APRI) and other non-invasive markers has been less studied in hepatitis C virus (HCV)-positive patients with concurrent end-stage renal disease to predict hepatic fibrosis. Can these be used to effectively decrease the number of biopsies done in these patients being evaluated for transplantation?

METHODS

Our study population included 255 patients with liver biopsy data. All patient information was collected and reviewed from medical records. The diagnostic accuracy of the predictive models was analyzed by calculating sensitivity, specificity, positive predictive value and negative predictive value.

RESULTS

The variables associated with F3-F4 were aspartate aminotransferase (P = 0.007), bilirubin (P ≤ 0.001), platelet count (P = 0.01) and APRI (P ≤ 0.001). The use of any one laboratory abnormality to predict liver biopsy scores did not show high positive predictive values (22.6-72.7%). Having abnormal liver findings or cirrhosis on imaging was associated with high specificities (92.0-97.8%) but low sensitivities (31.4-42.9%). Using APRI levels of ≥0.40 and ≤0.95 as an indication for liver biopsy, 50% of patients with F3-F4 would have correctly avoided having a biopsy. However, 33% of patients with F3-F4 would have been mislabeled and not be indicated for biopsy.

CONCLUSIONS

Our data suggest that there may not currently be a simple and sufficiently accurate non-invasive test to replace liver biopsy in renal transplant workup for HCV-positive patients. The risks outweigh the benefits when it comes to using non-invasive markers like the APRI.

Hepatitis C infection and chronic renal diseases

Hepatitis C virus (HCV) infection and chronic renal diseases can be linked in two different ways. Some forms of renal disease are precipitated by HCV infection, while patients with end-stage renal disease are at increased risk for acquiring HCV infection. Patients with chronic HCV infection and renal disease have a poor prognosis. Most studies on treatment of HCV and renal diseases have been uncontrolled trials with small number of subjects. So, there is a lack of evidence-based recommendations and guidelines on the management of this condition. In this review, we will attempt to provide the most recent insights on HCV infection both as a extrahepatic manifestations and as a complication of end-stage renal patients.

Management of hepatitis C in patients with chronic kidney disease

Chronic kidney disease represents a global health problem. Chronic hepatitis C virus (HCV) infection is prevalent in patients with end stage renal disease (ESRD) on hemodialysis (HD) and in renal transplant recipients with significant impact on morbidity and mortality. Furthermore, HCV can cause various forms of glomerulopathy with the predominant type being cryglobulinemia associated membranoproliferative glomerulonephritis. Liver enzymes are traditionally used as markers of liver injury; however, there is wide variation in aminotransferase levels in patients with ESRD. Therefore, diagnosis of chronic hepatitis C (CHC) in patients with ESRD is based on HCV antibody testing and further confirmation with polymerase chain reaction testing. Current standard therapy for CHC is composed of pegylated interferon and ribavirin. However, this combination is challenging in patients with ESRD due to its tolerability. We describe in this review relevant issues in epidemiology, diagnosis and management of CHC in ESRD, HD and renal transplant recipients.

Transient elastography to assess hepatic fibrosis in hemodialysis chronic hepatitis C patients

BACKGROUND AND OBJECTIVES

Although percutaneous liver biopsy (PLB) is the gold standard for staging hepatic fibrosis in hemodialysis patients with chronic hepatitis C (CHC) before renal transplantation or antiviral therapy, concerns exist about serious postbiopsy complications. Using transient elastography (TE, Fibroscan(®)) to predict the severity of hepatic fibrosis has not been prospectively evaluated in these patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A total of 284 hemodialysis patients with CHC were enrolled. TE and aspartate aminotransferase-to-platelet ratio index (APRI) were performed before PLB. The severity of hepatic fibrosis was staged by METAVIR scores ranging from F0 to F4. Receiver operating characteristic curves were used to assess the diagnostic accuracy of TE and APRI, taking PLB as the reference standard.

RESULTS

The areas under curves of TE were higher than those of APRI in predicting patients with significant hepatic fibrosis (≥F2) (0.96 versus 0.84, P<0.001), those with advanced hepatic fibrosis (≥F3) (0.98 versus 0.93, P=0.04), and those with cirrhosis (F4) (0.99 versus 0.92, P=0.13). Choosing optimized liver stiffness measurements of 5.3, 8.3, and 9.2 kPa had high sensitivity (93-100%) and specificity (88-99%), and 87, 97, and 93% of the patients with a fibrosis stage of ≥F2, ≥F3, and F4 were correctly diagnosed without PLB, respectively.

CONCLUSIONS

TE is superior to APRI in assessing the severity of hepatic fibrosis and can substantially decrease the need of staging PLB in hemodialysis patients with CHC.

Outpatient percutaneous liver biopsy: still a good option

OBJECTIVE

To assess security of "blind" percutaneous liver biopsy as an ambulatory procedure.

MATERIAL AND METHODS

Defining inclusion criteria, surveillance protocol, data from ultrasonography done 6 h after procedure and complications.

RESULTS

We analysed 192 percutaneous liver biopsies done between 2000-2007. There were no major complications and only a small number of minor complications. There were no deaths related to the procedure.

CONCLUSION

It is possible to perform percutaneous liver biopsy as an ambulatory procedure not expecting to find threatening complications.

Hepatitis C infection and chronic renal diseases

More than 170 million people worldwide are chronically infected with the hepatitis C virus (HCV), which is responsible for over 1 million deaths resulting from cirrhosis and liver cancers. Extrahepatic manifestations are also relevant and include mixed cryoglobulinemia, lymphoproliferative disorders, and kidney disease. HCV infection is both a cause and a complication of chronic kidney disease, occurring largely in the context of mixed cryoglobulinemia. This infection also represents a major medical and epidemiologic challenge in patients with end-stage renal disease on renal replacement therapy with dialysis or transplantation. In these settings the presence of HCV correlates with higher rates of patient mortality than in HCV-negative subjects on dialysis or undergoing kidney transplant. The major concern is the lack of safe and effective drugs to treat HCV-infected patients with chronic kidney disease. Unfortunately, there are no large-scale clinical trials in this population, especially those receiving renal replacement therapy, so that strong evidence for treatment recommendations is scant. This review article provides the readers with the most recent insights on HCV infection both as cause and complication of chronic kidney disease, discusses pitfalls and limitations of current therapies, and reports on preliminary experience with novel therapeutic agents, as well as directions for future research.

Serum levels of YKL-40 and hyaluronic acid as noninvasive markers of liver fibrosis in haemodialysis patients with chronic hepatitis C virus infection

Hepatitis C virus (HCV) infection is highly prevalent among end-stage renal disease (ESRD) patients undergoing haemodialysis and it is an important cause of morbidity and mortality in this population. The aim of this study was to evaluate the diagnostic value of YKL-40 and hyaluronic acid (HA) as noninvasive markers of liver fibrosis in 185 ESRD HCV-infected patients. Significant liver fibrosis was defined as METAVIR F2, F3 or F4 stages. Significant fibrosis was observed in 45 patients (24%). By univariate analysis, higher levels of YKL-40, HA, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) as well as reduced platelet count were associated with fibrosis. However, by multivariate analysis, only AST (P = 0.001), platelet count (P = 0.004) and HA (P = 0.042) were independently associated with significant fibrosis. For the prediction of significant fibrosis, the areas under receiver operating characterictic curve (AUROC) of the regression model (0.798) was significantly higher than the AUROC of YKL-40 (0.607) and HA (0.650). No difference was noted between the AUROC of the regression model and AST to platelet ratio index (APRI) (0.787). Values <8.38 of the regression model showed a negative predictive value of 94% and scores >or=9.6 exhibited a positive predictive value of 65%. If biopsy indication was restricted to scores in the intermediate range of the regression model, it could have been correctly avoided in 61% of the cases. In conclusion, APRI and a model based on AST, platelet count and HA showed better accuracy than YKL-40 and HA (when used solely) for the prediction of significant fibrosis in ESRD HCV-infected patients.

Simple blood tests as noninvasive markers of liver fibrosis in hemodialysis patients with chronic hepatitis C virus infection

HCV infection is common among patients with end-stage renal disease (ESRD) on hemodialysis, and it has been considered an independent risk factor for mortality in this setting. Although liver biopsy in ESRD patients with HCV infection is useful before kidney transplantation, it carries a high risk of complications. We sought to assess the diagnostic value of noninvasive markers to stage liver fibrosis in 203 ESRD HCV-infected patients. Univariate and multivariate analysis were used to identify variables associated with significant fibrosis (METAVIR F2, F3, or F4 stages). Significant liver fibrosis was observed in 48 patients (24%). Logistic regression analysis identified AST and platelet count as independent predictors of significant fibrosis (P < 0.001 and P = 0.001, respectively). The area under the receiver operating characteristic curve of the AST to platelet ratio index (APRI) for predicting significant fibrosis was 0.801. An APRI < 0.40 accurately identified patients with fibrosis stage 0 or 1 in 93% of the cases (NPV = 93%), and all misclassified subjects were F2. A cutoff > or = 0.95 to confirm significant fibrosis had a PPV of 66%. If biopsy indication was restricted to APRI scores in the intermediate range (> or = 0.40 and < 0.95), 52% of liver biopsies could have been correctly avoided.

CONCLUSION

Stage of liver fibrosis can be reliably predicted in ESRD HCV-infected subjects by simple and widely available blood tests such as AST levels and platelet count. These tests might obviate the requirement for a liver biopsy in a significant proportion of those patients.