Chronic hepatitis: what is activity and how should it be assessed?

IIB or not IIB, part 1: retrospective evaluation of Kenney-Doig categorization of equine endometrial biopsies at a veterinary diagnostic laboratory and comparison with published reports

The Kenney-Doig scale is a histopathology categorization (grading) system often used as the standard for assessing endometrial disease and communicating prognostic fertility information for equine breeding prospects. We investigated how Kenney-Doig categories compared within the same institution and across different institutions to determine if observer variability may contribute to category frequencies. We conducted a retrospective analysis of all equine endometrial submission records between 1998 and 2018 at the Western College of Veterinary Medicine (WCVM) and Prairie Diagnostic Services (PDS). Of 726 biopsies, we found the following category distribution: 46 of 726 (6.3%) I, 307 of 726 (42.3%) IIA, 326 of 726 (44.9%) IIB, and 47 of 726 (6.5%) III. We also conducted a review of the literature and included 6 studies reporting Kenney-Doig category distributions. Chi-square analysis showed significant differences between the category distribution found at WCVM and PDS and the category distribution reported in the 6 studies. To account for differences in mare populations, individual category distributions were generated for 5 pathologists at the WCVM and PDS. The Fisher exact test among these 5 Kenney-Doig categories revealed significant differences in category tendencies, suggesting that observer variation affects the use of the scale. Our results suggest that there is a need for prospective inter-rater and intra-rater agreement studies of the repeatability of the Kenney-Doig scale.

What is expected from the pathologist in the diagnosis of viral hepatitis?

The clinician expects from the pathologist a clinically relevant diagnosis on the basis of liver biopsy interpretation. Today, a liver biopsy, as invasive procedure, is only justified when a significant benefit for the patient can be expected particularly with respect to the clinical management. Consequently, liver biopsy is usually not required in uncomplicated acute viral hepatitis. It is, however, an important diagnostic tool in chronic hepatitis and in transplanted liver to confirm the clinical diagnosis and to assess stage and grade of necroinflammation, treatment efficiency, and concurrent diseases. The diagnosis of liver disease is based on teamwork between clinician and pathologist. Evaluation of the biopsy in the clinical context requires clinical information and appropriate size and handling of the biopsy specimen. Aim of this review is the discussion of morphologic features of acute and chronic viral hepatitis with regard to their clinical relevance.

Pathology of chronic hepatitis B and chronic hepatitis C

Histologic evaluation of the liver is a major component in the medical management and treatment algorithm of patients with chronic hepatitis B (HBV) and chronic hepatitis C (HCV). Liver biopsy in these patients remains the gold standard, and decisions on treatment are often predicated on the degree of damage and stage of fibrosis. This article outlines the clinical course and serologic diagnosis of HBV and HCV for the clinician and the pathologist, who together have a close working relationship in managing patients with acute and chronic liver disease. The salient histologic features are elucidated in an attempt to provide the clinician with an understanding of the basic histopathology underlying chronic HCV and HBV.

Contrast-enhanced ultrasound to evaluate the severity of chronic hepatitis C

BACKGROUND

Non-invasive techniques are being developed to assess the severity of liver disease. Haemodynamic changes in the hepatic circulation during the development of liver disease can be evaluated with contrast-enhanced ultrasound.

AIM

To evaluate the possible correlation between ultrasound contrast-agent transit times and different stages of chronic hepatitis C.

PATIENTS

Sixteen patients with clinically evident hepatitis C virus-related cirrhosis, 22 non-cirrhotic patients with chronic hepatitis C and 14 controls with no clinical evidence of liver disease were studied.

METHODS

Contrast-enhanced hepatic ultrasonography was performed with a sulphur hexafluoride-filled microbubble contrast agent, and time curves of hepatic vein signal intensity were analysed to determine the time of enhancement onset (hepatic vein arrival time) and peak enhancement (hepatic vein peak enhancement).

RESULTS

Hepatic vein arrival time in cirrhotic patients was significantly shorter (p<0.001) than in non-cirrhotic patients and controls. Within the group with chronic hepatitis C, METAVIR scores of fibrosis and necro-inflammatory changes had no significant effect on hepatic vein arrival times.

CONCLUSION

Analysis of the time of onset of ultrasound contrast enhancement of the hepatic vein appears to be a simple, non-invasive method for reliably excluding cirrhosis with signs of portal hypertension, but not for assessing the severity of either chronic hepatitis C or cirrhosis.

Quantitative assessment of liver fibrosis: a novel automated image analysis method

BACKGROUND

Semiquantitative staging of liver fibrosis is a highly subjective procedure and may lead to an uncertainty in judgment regarding the degree of severity and hence the progression of the disease.

AIM

In this work, we present an automated quantification system (AQS) for evaluating the degree of severity of fibrosis in liver biopsies based on Ishak et al.'s classification. Accordingly, liver fibrosis is classified into six classes depending on its severity and progression. The described system is of special value in accurately assessing the prognosis of chronic liver disease.

METHODS

In our method, we tried to approximate the architecture of the fibrosis in the subject sample using texture features and shape representation of the fibrosis structural expansion with an overall accuracy of about 98%.

RESULTS AND CONCLUSION

The presented AQS is considered to be a novel approach in the domain of automatic liver fibrosis quantification. It is a true quantification and intelligent approach that attempts to utilize the current semiquantitative methods of liver fibrosis assessment to turn them into real quantitative ones with significant reduction in variability and subjectivity. We propose that our method can be adopted by a panel of expert liver pathologists and software to be developed and used on a wide scale.

Serum markers detect the presence of liver fibrosis: a cohort study

BACKGROUND & AIMS

Histologic examination of a liver biopsy specimen is regarded as the reference standard for detecting liver fibrosis. Biopsy can be painful and hazardous, and assessment is subjective and prone to sampling error. We developed a panel of sensitive automated immunoassays to detect matrix constituents and mediators of matrix remodeling in serum to evaluate their performance in the detection of liver fibrosis.

METHODS

In an international multicenter cohort study, serum levels of 9 surrogate markers of liver fibrosis were compared with fibrosis stage in liver biopsy specimens obtained from 1021 subjects with chronic liver disease. Discriminant analysis of a test set of samples was used to identify an algorithm combining age, hyaluronic acid, amino-terminal propeptide of type III collagen, and tissue inhibitor of matrix metalloproteinase 1 that was subsequently evaluated using a validation set of biopsy specimens and serum samples.

RESULTS

The algorithm detected fibrosis (sensitivity, 90%) and accurately detected the absence of fibrosis (negative predictive value for significant fibrosis, 92%; area under the curve of a receiver operating characteristic plot, .804; standard error, .02; P < .0001; 95% confidence interval, .758-.851). Performance was excellent for alcoholic liver disease and nonalcoholic fatty liver disease. The algorithm performed equally well in comparison with each of the pathologists. In contrast, pathologists' agreement over histologic scores ranged from very good to moderate (kappa = .97-.46).

CONCLUSIONS

Assessment of liver fibrosis with multiple serum markers used in combination is sensitive, specific, and reproducible, suggesting they may be used in conjunction with liver biopsy to assess a range of chronic liver diseases.

Feasibility of histological grading and staging of chronic viral hepatitis using specimens obtained by thin-needle biopsy

We performed a retrospective study to investigate the feasibility of grading and staging of chronic viral hepatitis on specimens obtained by means of thin-needle biopsy (TNB; 20G) using the modified Ishak-system (J Hepatol 1995; 22:696-699). Specimens obtained using large-needle biopsy (LNB; 17G) served as a control. A total of 100 biopsy specimens from 88 patients were included in the study. Of the patients, 30 suffered from chronic hepatitis B, 54 from chronic hepatitis C, and 4 from both; 59 specimens were obtained by TNB and 41 by LNB. All four categories of the Ishak-system, i.e., interface hepatitis, confluent necrosis, lobular inflammation and portal inflammation, could be applied to TNB specimens and provided similar total scores to those observed in LNB specimens. Specimens obtained by TNB facilitated the diagnosis of liver cirrhosis. However, they bore the risk of underestimating the presence of cirrhosis in favor of advanced bridging fibrosis, whereas no differences were found in the overall recognition of liver fibrosis. Intra- and interobserver variabilities were not affected by the needle size. For the interobserver agreement, the kappa values for the category of inflammation ranged from 0.003 to 0.419 (TNB) and 0.096 to 0.470 (LNB) and for staging we noted kappa values of 0.351 (TNB) and 0.456 (LNB). Reproducibility increased when a tolerance of +/-1 was accepted for grading (total score) and staging; in this case, observer variability was less than 20%. This study showed that grading and staging of chronic viral hepatitis is feasible in TNB specimens and that intra- and interobserver variability poses a greater problem than needle size.

Role of non-alcoholic steatohepatitis in methotrexate-induced liver injury

BACKGROUND AND AIMS

Hepatotoxicity, especially liver fibrosis, is the major concern with long-term, 'low-dose' oral methotrexate (MTX) therapy for psoriasis. The histological features are non-specific and resemble those of non-alcoholic steatohepatitis (NASH). Moreover, most of the risk factors of MTX-induced liver injury are also associated with NASH. In this study, we investigate whether NASH contributes to the prevalence and progression of MTX-induced liver injury in patients receiving MTX for psoriasis.

METHODS

Clinical details, including MTX dosage schedules and risk factors for liver injury, was documented for 24 patients on long-term MTX therapy for psoriasis. Serial liver biopsies were graded according to the Roenigk classification scale and a recently proposed grading and staging system for NASH.

RESULTS

Thirteen of the 17 patients who had a NASH-like pattern of liver injury also had the risk factors for NASH obesity and/or diabetes, and all had progressive liver injury. The other four patients had no risk factors, but a mean cumulative dose of 6.5 g. Seven patients, who did not have a NASH-like pattern of injury, had a mean cumulative dose of 3.8 g. There was a positive correlation between the cumulative dose, risk factors and progression when the biopsies were scored by the modified grading and staging classification for NASH, but not with the Roenigk system.

CONCLUSIONS

Non-steatohepatitis, probably aggravated by MTX, is an important cause of liver injury in patients on long-term, 'low-dose' MTX treatment for psoriasis. In addition, MTX alone can cause a NASH-like pattern of injury that is at least, in part, caused by a higher cumulative dose.

Expression of the mucosal vascular addressin, MAdCAM-1, in inflammatory liver disease

AIMS/BACKGROUND

The integrin alpha4beta7 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are involved in normal recirculation of lymphocytes between the blood and the tissues of the gastrointestinal tract. In this study we have examined the expression of MAdCAM-1 in human liver.

METHODS

MAdCAM-1 expression was determined in archival human liver tissues by immunohistochemistry.

RESULTS

While MAdCAM-1 was not detected in normal fetal or adult human liver, expression was observed in association with portal tract inflammation in a variety of liver diseases. Detailed analysis of liver biopsies from patients with hepatitis C showed a positive correlation between the portal/periportal component of the histological activity index (HAI) grade and the presence or absence of MAdCAM-1 expression.

CONCLUSION

MAdCAM-1 expression may be important in the recruitment of lymphocytes to the liver during inflammation.

Broadsheet number 47: Chronic hepatitis: an update with guidelines for histopathological assessment of liver biopsies. Board of Education of The Royal College of Pathologists of Australasia

The liver biopsy remains the 'gold standard' for the diagnosis of chronic hepatitis, particularly since it is the only investigation that permits assessment of the severity (grade of histological activity and stage of fibrosis) of liver injury. As outlined below, the liver biopsy is invaluable for both diagnosis and the monitoring of therapy. To optimise the value of the liver biopsy, a standardised approach for assessment and reporting of chronic hepatitis is recommended.

Grading and scoring in histopathology

In many areas of histopathology a nominal category, such as a diagnosis of breast carcinoma, does not give enough information for the referring clinician to make decisions about patient prognosis and treatment. Therefore scoring and grading systems have been developed which provide additional information. This article reviews the principles behind these systems with particular reference to the relationships between the natural clustering (or nonclustering) of cases and the imposition of arbitrary class boundaries on such distributions. The difference between real numbers and the ordinal categorical numeric labels, which are often produced by histopathology scoring systems, is discussed. The reproducibility of scoring and grading systems is reviewed and generic suggestions are given for developing new systems and for their validation.

Mild abnormalities in liver histology associated with chronic hepatitis: distinction from normal liver histology

BACKGROUND

Chronic hepatitis C virus infection associated with contaminated anti-D immunoglobulin has become an issue of recent concern. The clinical course of chronic hepatitis C infection is unpredictable and histological assessment is felt to be the most reliable means of assessing disease status. Semiquantitative scoring systems have been devised, which assess degree of necroinflammatory disease activity (grade) and extent of disease progression with fibrosis (stage) in chronic hepatitis. Often, using these systems, biopsies of anti-D associated chronic hepatitis C cases show mild changes only, with low scores. The significance of these low scores is uncertain.

AIMS

To evaluate the significance of low scores in chronic hepatitis.

METHODS

Liver biopsies were assessed from two groups of patients in whom liver histology would be expected to be normal: 30 cases of Gilbert's syndrome and 13 necropsy cases of young people (< 45 years) with no history or risk factors for liver disease. These biopsies were scored using the histological activity index of Knodell et al and its recent modification (separation of scores for grade and stage) by Ishak et al.

RESULTS

Twenty of 30 cases of Gilbert's syndrome and 11 of the 13 necropsy cases had chronic hepatitis scores of 1 or 2, whereas only eight cases of Gilbert's and two necropsy cases had scores of 0. The remaining two Gilbert's cases had scores of 3 and 5. Similar results were found using both the histological activity index of Knodell et al and the method of Ishak et al.

CONCLUSION

The finding of low but positive scores using these systems in people with normal liver histology questions the reliability and significance of finding such scores in patients with chronic hepatitis and is of particular concern in the evaluation of chronic hepatitis C infection.