Chronic viral hepatitis B and C: an argument against the conventional classification of chronic hepatitis

Chronic viral hepatitis: the histology report

In chronic viral hepatitis, the role of liver biopsy as a diagnostic test has seen a decline, paralleled by its increasing importance for prognostic purposes. Nowadays, the main indication for liver biopsy in chronic viral hepatitis is to assess the severity of the disease, in terms of both necro-inflammation (grade) and fibrosis (stage), which is important for prognosis and therapeutic management. Several scoring systems have been proposed for grading and staging chronic viral hepatitis and there is no a general consensus on the best system to be used in the daily practice. All scoring systems have their drawbacks and all may be affected by sampling and observer variability. Whatever the system used, a histological score is a reductive approach since damage in chronic viral hepatitis is a complex biological process. Thus, scoring systems are not intended to replace the detailed, descriptive, pathology report. In fact, lesions other than those scored for grading and staging may have clinical relevance and should be assessed and reported. This paper aims to provide a systematic approach to the interpretation of liver biopsies obtained in cases of chronic viral hepatitis, with the hope of helping general pathologists in their diagnostic practice.

Quantitative assessment of fibrosis and steatosis in liver biopsies from patients with chronic hepatitis C

BACKGROUND

Hepatic fibrosis is one of the main consequences of liver disease. Both fibrosis and steatosis may be seen in some patients with chronic hepatitis C and alcoholic liver disease (ALD).

AIMS

To quantitate fibrosis and steatosis by stereological and morphometric techniques in patients with chronic hepatitis C and compare the results with a control group of patients with ALD. In addition, to correlate the quantitative features of fibrosis with the Ishak modified histological score.

MATERIALS AND METHODS

Needle liver biopsies from 86 patients with chronic hepatitis C and from 32 patients with alcoholic liver disease (disease controls) were analysed by stereological and morphometric analyses using the Prodit 5.2 system. Haematoxylin and eosin and Picro-Mallory stained sections were used. The area fractions (A(A)) of fibrosis, steatosis, parenchyma, and other structures (bile duct and central vein areas) were assessed by stereological method. The mean diameters of fat globules were determined by morphometric analysis.

RESULTS

Significant differences were found in the A(A) of fibrosis, including fibrosis within portal tract areas, between chronic hepatitis C patients and those with ALD (mean (SD): 19.14 (10.59) v 15.97 (12.51)). Portal and periportal (zone 1) fibrosis was significantly higher (p = 0.00004) in patients with chronic hepatitis C compared with the control group (mean (SD): 9.04 (6.37) v 3.59 (3.16)). Pericentral fibrosis (zone 3) occurred in both groups but was significantly more pronounced in patients with ALD. These results correlate well with the modified Ishak scoring system. However, in patients with cirrhosis (stage 6) with chronic hepatitis C the A(A) of fibrosis varied between 20% and 74%. The diameter of fat globules was significantly lower in patients with hepatitis C (p = 0.00002) than the ALD group (mean (SD): 14.44 (3.45) v 18.4 (3.32)). Microglobules were more frequent in patients with chronic hepatitis C than in patients with ALD. In patients with chronic hepatitis C, the fat globules had a zonal distribution in comparison with pan steatosis in ALD.

CONCLUSION

Quantitative, stereological techniques are simple and reliable for evaluating hepatic fibrosis and steatosis in chronic hepatitis C. They are most useful for assessing the origin, location, and the stage of fibrosis. Stereology and morphometry are recommended for the quantitation of fibrosis and steatosis, particularly for the evaluation of new treatment strategies in patients with chronic hepatitis C.

Chronic liver disease in heterozygous alpha1-antitrypsin deficiency PiZ

BACKGROUND/AIMS

The contribution of the heterozygous state PiZ of alpha1-antitrypsin deficiency (AATD) to the pathogenesis of chronic liver disease is debated. We analyzed whether patients with this genetic defect carrying a single PiZ gene are at increased risk for developing chronic liver disease.

METHODS

1847 consecutive biopsy cases and 1030 autopsy cases of Caucasian adults were screened immunohistochemically for PiZ deposits. The zygosity status was analyzed by single-strand conformational polymorphism (SSCP) and by sequencing DNA extracted from paraffin-embedded tissue.

RESULTS

All analyzed biopsy cases were heterozygous for the PiZ mutation. The biopsy group revealed a significantly higher rate of PiZ-positive cases (3.4%) than the autopsy group (1.8%) (p=0.019). PiZ deposits ranged from scarce granules to extensive globular inclusions as in homozygous AATD of PiZ type. The extent of PiZ deposits correlated well with the inflammatory activity and stage of fibrosis. Cirrhotic livers contained globular PiZ deposits significantly more often than the biopsies with minor fibrosis. PiZ-positive biopsies from patients without concurrent liver disease (n= 26) revealed only minor fibrosis in the age group between 20 and 39 years, but significantly more severe fibrosis and significantly more PiZ deposits in the older age groups. Biopsies with concurrent liver disease (n=28) presented with significantly more severe inflammation and fibrosis, and more PiZ deposits than the cases without concurrent liver disease.

CONCLUSIONS

Patients with heterozygous AATD of PiZ type bear an increased risk for chronic liver disease. If at all, this genetic defect will become clinically relevant only in middle-aged or old adults. It rarely causes liver cirrhosis even without concurrent liver disease. It can aggravate or can be aggravated by advanced coexistent chronic liver diseases. PiZ immunohistochemistry is an easy, highly specific method to detect this metabolic defect on liver biopsies.

The "interferon sensitivity determining region" of hepatitis C virus is a stable sequence element

BACKGROUND/AIMS

A sequence of 40 amino acids within the nonstructural protein 5A of hepatitis C virus (HCV) has been suggested to be an interferon sensitivity determining region (ISDR). The variations in the ISDR after 12-14 years of chronic infection and the correlation between ISDR and interferon response were studied in patients who were infected by the same HCV isolate.

METHODS

We determined the HCV-ISDRs of 13 chronically infected patients by direct sequencing of polymerase chain reaction products. All patients were infected by isolate HCV-AD78, but differed with respect to their sensitivity to interferon. Four patients were complete responders, two patients were non-responders, and seven showed a partial response.

RESULTS

The ISDR of HCV-AD78 differed from a prototypical HCV-1b sequence in one amino acid and was therefore classified as an intermediate type. Direct sequencing of the HCV-ISDRs of the patients 12-14 years after infection, but before interferon therapy, revealed a rate of 2.2x10(-3) nucleotide substitutions per site per year, resulting in only single intermediate type amino acid exchanges. All sequences ranked with the intermediate type. Moreover, during interferon treatment no selection to a wild type ISDR was observed in five partial responders.

CONCLUSIONS

Within the homogeneous patient group examined here, no correlation was found between the ISDR and the interferon response. Recent studies found only a small number of mutant type ISDRs in Europe. Additionally, our results indicate that the ISDR is a stable sequence element. This provides an explanation for the divergent data relating to the importance of the ISDR in different geographical regions.

Liver iron and fibrosis during long-term treatment with deferiprone in Swiss thalassaemic patients

Serum ferritin levels, hepatic histology and iron concentration were studied in a 'veteran' group of seven Swiss beta-thalassaemic patients after 93-99 months of treatment with the oral iron chelator deferiprone (L1), and another four patients who had received 54-82 months of L1 therapy. Despite continuous compliance, unexplained resurgence of serum ferritin levels occurred in 4/7 patients of the 'veteran' group after 4-5 years on L1. In three of these a concomitant increase of liver iron was also observed. Hepatic histology revealed significantly higher degrees of fibrosis in 6/11 hepatitis C (HC)-positive patients (fibrosis scores 1-5, mean 3.0) than in the HC-negative group (fibrosis score 0-2, mean 0.8). Two HC-negative patients had no detectable fibrosis after 98 and 93 months on deferiprone. Therefore the hepatic pathology in these patients cannot definitely be attributed as a side-effect of deferiprone. Chronic active hepatitis C and the accumulation of iron are the major causative factors to be considered.

Chronic hepatitis associated with leptospiral infection in vaccinated beagles

Sixteen juvenile Beagle dogs originating from a single breeding colony and regularly vaccinated against Leptospira interrogans (serogroups Canicola and Icterohaemorrhagiae) developed a clinical syndrome characterized by retarded growth, weight loss and often ascites. Over a 10-month period, post-mortem examinations were performed on all affected dogs. Gross lesions were confined to the liver which was often firm, tan-coloured and mottled. Microscopically, hepatic lesions ranged from those of severe chronic hepatitis to mild diffuse hepatocellular vacuolation, with bile stasis, occasional scattered lymphocytic aggregates and haemosiderin granulomas. Special stains and electron microscopy revealed spirochaetes within bile canaliculi. The genus Leptospira was recognized by immunohistochemical methods in nine dogs. Leptospires were isolated from six dogs, but serological tests failed to detect significant titres of antibody to L. interrogans in these animals. A serological survey of 37 kennelmates demonstrated that 20 dogs had high titres of serogroup Australis leptospiral antibody, which could not have resulted from vaccination. These findings strongly suggest a connection between the presence of leptospires and the hepatic lesions.

The apoptosis protector, bcl-2 protein, is downregulated in bile duct epithelial cells of human liver allografts

BACKGROUND/AIMS

Apoptosis of bile duct cells occurs in hepatic allografts and is correlated with acute rejection. bcl-2 protein counteracts apoptosis and prolongs cell survival. We therefore tested the expression of bcl-2 protein in bile ducts of liver grafts in comparison with those of liver cirrhosis.

METHODS

115 biopsies from 17 liver allografts and 47 biopsies of liver cirrhosis were analyzed and compared with 22 normal controls and with biopsies from patients with primary sclerosing cholangitis or primary biliary cirrhosis. bcl-2 protein and PCNA (proliferating cell nuclear antigen) expression was assessed using immunohistochemistry, and apoptosis was analyzed employing in situ DNA end-labeling.

RESULTS

A high apoptotic rate was detected in bile duct cells of allograft biopsies. In contrast to controls, bile duct cells of allografts and liver cirrhosis had high proliferative activity (mean PCNA labeling index: 1.0% vs. 40.7% and 18.6%, respectively). In liver grafts, bcl-2 protein positivity of bile duct and ductular cells was found in 3.6% and 4.4% of sections, respectively, and in cirrhosis in 44% and 79%, respectively (allografts vs. cirrhosis p<0.01). In controls, only one biopsy was bcl-2 positive.

CONCLUSIONS

Whereas increased proliferative activity of small bile ducts and ductules in cirrhosis is associated with a high degree of bcl-2 expression, bile duct and ductular cells in liver grafts have a very low bcl-2 protein reactivity, even though their proliferative activity is high. These findings suggest that downregulation of bcl-2 expression in allograft bile duct cells might play a role in the increased apoptosis of these cells in acute rejection.

Fixed versus titrated interferon-alpha 2B in chronic hepatitis C. A randomized controlled multicenter trial. The Swiss Association for the Study of the Liver

BACKGROUND/AIM

Interferon has become the mainstay of treatment of chronic hepatitis C; however, duration of treatment and dose remain unresolved questions. The present study aimed to compare standard dose interferon with a titrated dose regimen carried out for 1 year.

METHODS

This was a randomized, controlled multicenter trial. Patients with chronic hepatitis C were randomly allocated to a control group (n = 30), to a fixed dose group (n = 31) where interferon-alpha 2b 3 MU thrice weekly was given for 1 year or a titrated group (n = 34) where interferon was titrated starting at 5 MU thrice weekly to the lowest dose keeping the patient in remission as assessed by a normal ALT value. Liver biopsies were obtained before and at the end of treatment; in addition, galactose elimination capacity was measured as a measure of cytosolic function.

RESULTS

In the control, fixed and titrated groups a complete response was achieved in 2/29, 10/28 and 15/31, respectively (p < 0.001 in favor of treatment, p = n.s. for the two treatments). The corresponding figure for sustained response was 1/29, 5/28 and 6/ 31 (p = n.s). In the titrated group, a complete (sustained) response was achieved with 5 MU in 2 (2), with 4 MU in 1 (0), with 3 MU in 4 (0), with 2 MU in 3 (0) and with 1 MU in 5 (4). Liver biopsy score and galactose elimination capacity improved significantly in responders but not in treatment failures.

CONCLUSIONS

Both fixed and titrated dosing of interferon given for 1 year induced virus clearance in only a minority of treated patients. However, in a small number of patients, a complete and sustained response can be achieved with low doses of interferon. Dose titration could be an interesting approach to decreasing the cost and side effects in the treatment of chronic hepatitis C.

Standardized reporting of histological diagnoses for non-neoplastic liver conditions in needle biopsies

The importance of standardizing surgical pathology reports is emerging from the literature. The use of checklists has recently been proposed for diagnosing the major tumour types, but no attention has been given to non-neoplastic conditions. In this paper a checklist for standard reports of liver needle biopsies for non-neoplastic conditions is presented.