Type 1 and type 2 autoimmune hepatitis in adults share the same clinical phenotype

BACKGROUND

Autoimmune hepatitis (AIH) is historically classified into type 1 and type 2 on the basis of the autoantibody profile, anti-nuclear and/or anti-smooth muscle antibodies being the serological markers of type 1 AIH, whereas anti-liver/kidney microsomal antibody type 1 and/or anti-liver cytosol antibody type 1 characterise type 2 AIH.

AIM

To evaluate whether such a distinction is justified on the basis of different expression of the disease in adults.

METHODS

Twenty-six adult patients with type 2 AIH and 52 age- and sex-matched patients with type 1 AIH, representative of the entire cohort of adults with type 1 AIH, were compared at onset and during follow-up.

RESULTS

At diagnosis, median age was 26 years (range 17-53), female sex 86%, acute presentation 43%, severe liver histology 54%, cirrhosis 14%, complete response to treatment 52%, progression of the disease 17%, and median disease duration 72 months (range 12-280). HLA-DRB1*0301 was present in 26%, HLA-DRB1*0401 in 23% and HLA-DRB1*0701 in 25%. Clinical presentation, biochemical parameters, severe liver histology, genetic profile, response rate and progression of the disease were identical between type 1 and type 2 AIH.

CONCLUSION

There is not enough clinical, biochemical, histological or genetic reason to subdivide adults with autoimmune hepatitis into type 1 and type 2 on the basis of the autoantibody profile, and the term 'autoimmune hepatitis' without qualification should be preferred.

ARFI elastography in patients with chronic autoimmune liver diseases: A preliminary study

OBJECTIVE

Acoustic radiation force impulse (ARFI) is a new software-based technique that evaluates liver stiffness during B-mode ultrasonography. The purpose of this study was to evaluate the accuracy of ARFI in distinguishing patients with chronic autoimmune liver disease from healthy subjects.

MATERIAL AND METHODS

We enrolled 9 adult patients (8 women, 1 man; age 48.1 ± 12.8 years) with chronic autoimmune disease (primary biliary cirrhosis (PBC, n = 3), autoimmune hepatitis (AIH, n = 2), primary sclerosing cholangitis (PSC, n = 1) and overlap syndromes, (n = 3) who underwent a liver biopsy and 11 healthy volunteers (age 34.7 ± 10.4 years; 7 women, 4 men). Liver stiffness was evaluated and expressed as the shear wave velocity (SWV) in m/sec. We used a US scanner Siemens-Acuson S2000, evaluating the right liver lobe and the left liver lobe.

RESULTS

THE SWV WAS SIGNIFICANTLY HIGHER IN CASES (RIGHT LOBE: 1.51 ± 0.44; left lobe: 1.57 ± 0.40) than in controls (right lobe: 1.08 ± 0.10; left lobe: 1.12 ± 0.13) (right lobe: P = 0.002; left lobe: P = 0.013). We found no significant correlation between right and left lobe SWVs in cases (P = 0.779) or controls (P = 0.385). The SWV cut-off that best distinguished cases from controls was 1.25 m/sec (accuracy: AUC=0.885; sensitivity: 70.6%; specificity: 95.5%).

CONCLUSIONS

ARFI elastography is a noninvasive ultrasonographic technique that can differentiate healthy subjects from patients with fibrotic stages of chronic liver disease.

Antibodies to SS-A/Ro-52kD and centromere in autoimmune liver disease: a clue to diagnosis and prognosis of primary biliary cirrhosis

BACKGROUND

Primary biliary cirrhosis (PBC) may be associated with various rheumatological disorders.

AIM

To investigate the frequency and significance of 'rheumatological' antinuclear antibodies in the field of autoimmune chronic liver disease, with special regard to PBC.

METHODS

We studied 105 patients with PBC, 162 autoimmune liver disease controls (type 1 and 2 autoimmune hepatitis, primary sclerosing cholangitis), 30 systemic lupus erythematosus and 50 blood donors. Sera were tested for the presence of antibodies to extractable nuclear antigens (anti-ENA) by counterimmunoelectrophoresis, enzyme-linked and immunoblot (IB) assay, and for the presence of anti-centromere antibodies (ACA) by indirect immunofluorescence on HEp-2 cells and IB.

RESULTS

The overall prevalence of IB-detected anti-ENA in PBC (30%) was higher than in type 1 autoimmune hepatitis (2.5%, P < 0.0001), type 2 autoimmune hepatitis (0%, P < 0.0001) and primary sclerosing cholangitis (11.5%, P = 0.006) and lower than in systemic lupus erythematosus (53%, P = 0.03). The most frequent anti-ENA reactivity in PBC was anti-SSA/Ro-52kD (28%). ACA were detected by IB in 21% PBC patients and never in the other subjects (P < 0.0001). Anti-SS-A/Ro/52kD positive PBC patients had at the time of diagnosis a more advanced histological stage (P = 0.01) and higher serum levels of bilirubin (P = 0.01) and IgM (P = 0.03) compared with negative ones.

CONCLUSIONS

In the autoimmune liver disease setting, anti-SS-A/Ro-52kD and ACA have a high specificity for PBC and can thus be of diagnostic relevance in anti-mitochondrial antibodies negative cases. If confirmed in further studies with adequate follow-up, anti-SS-A/Ro-52kD antibodies might identify PBC patients with a more advanced and active disease.

Antinuclear antibodies giving the 'multiple nuclear dots' or the 'rim-like/membranous' patterns: diagnostic accuracy for primary biliary cirrhosis

BACKGROUND

Serum antinuclear antibodies giving the 'multiple nuclear dots' or the 'rim-like/membranous' patterns are frequently detected by indirect immunofluorescence on HEp-2 cells in patients with primary biliary cirrhosis.

AIM

To assess the accuracy of multiple nuclear dot and rim-like/membranous antinuclear antibodies for the diagnosis of primary biliary cirrhosis.

METHODS

Sera from 4371 consecutive patients referred to our laboratory were analysed under code for antinuclear antibodies testing by indirect immunofluorescence on HEp-2 cells.

RESULTS

Review of the clinical records of the 4371 patients allowed identification of 101 patients with antimitochondrial antibody-positive primary biliary cirrhosis and 22 with antimitochondrial antibody-negative variant. Multiple nuclear dot and/or rim-like/membranous patterns were found in 59 (1.3%) of the 4371 patients: 31 antimitochondrial antibody-positive primary biliary cirrhosis, 17 antimitochondrial antibody-negative primary biliary cirrhosis and 11 non-primary biliary cirrhosis. The specificity for primary biliary cirrhosis of both the antinuclear antibodies pattern was 99%. Positive predictive value and likelihood ratio for a positive test were 86% (95% CI: 72.7-94) and 221 (95% CI: 91.7-544) for multiple nuclear dot, 79% (95% CI: 62.2-90.1) and 132 (95% CI: 56.8-312.7) for rim-like/membranous, respectively.

CONCLUSIONS

Multiple nuclear dot and rim-like/membranous antinuclear antibodies are rare findings. Their positivity strongly suggests the diagnosis of primary biliary cirrhosis, irrespective of antimitochondrial antibody status. The high specificity for primary biliary cirrhosis makes them a useful diagnostic tool especially in antimitochondrial antibody-negative patients.

Antibodies to filamentous actin (F-actin) in type 1 autoimmune hepatitis

AIMS

To evaluate the diagnostic significance of anti-filamentous actin antibodies (A-FAA) assessed with a commercial ELISA in comparison with immunofluorescence reactivity and patterns of anti-smooth muscle antibodies (SMA); and to correlate A-FAA positivity with clinical, immunogenetic, laboratory, and histological features in patients with autoimmune hepatitis type 1 (AIH-1).

METHODS

We studied 78 consecutive untreated AIH-1 patients and 160 controls: 22 with autoimmune hepatitis type 2 (AIH-2), 51 with hepatitis C, 17 with coeliac disease (CD), 20 with primary biliary cirrhosis (PBC) and 50 blood donors. SMA was evaluated by indirect immunofluorescence (IIF) on frozen sections of rat tissues, and A-FAA with a modified commercial ELISA.

RESULTS

SMA was detected by IIF in 61 (78%) of 78 AIH-1 patients, of whom 47 (60%) had the SMA-T/G and 14 (18%) the SMA-V pattern. Of the pathological controls, 32 (20%) had the SMA-V pattern (25 with hepatitis C, 2 with AIH-2, 2 with PBC, 3 with CD). A-FAA were present in 55 AIH-1 patients (70.5%; 46 with SMA-T/G, 7 with SMA-V, and 2 SMA-negative), and in 10 controls (6%), of whom five had hepatitis C, two AIH-2, two PBC and one CD. The association between A-FAA and the SMA-T/G pattern was statistically significant (p<0.0001). A-FAA levels were higher in SMA-T/G positive than SMA-V positive AIH-1 patients and controls (p<0.0001). A-FAA positivity was significantly associated with higher gamma-globulin and IgG levels, but did not correlate with other considered parameters.

CONCLUSION

The modified A-FAA ELISA strictly correlates with the SMA-T/G pattern and is a reliable and operator independent assay for AIH-1. Detection of A-FAA, even if devoid of prognostic relevance, may be useful when interpretative doubts of standard IIF arise.

Anti-cyclic citrullinated peptide antibodies in type 1 autoimmune hepatitis

BACKGROUND

Besides the autoantibodies included in the diagnostic criteria of type 1 autoimmune hepatitis, many other autoantibodies have been described in this condition. Recently, antibodies against cyclic citrullinated peptide have been validated as specific diagnostic and prognostic markers of rheumatoid arthritis.

AIM

To assess whether these antibodies are part of the autoantibody repertoire of type 1 autoimmune hepatitis and correlate with rheumatological manifestations.

METHODS

Antibodies against cyclic citrullinated peptide were tested by a commercially available enzyme-linked immunosorbent assay.

RESULTS

The antibodies were found in 12 of 133 (9%) type 1 autoimmune hepatitis, two of 49 (4%) with primary biliary cirrhosis, one of 80 (1%) with hepatitis C virus-related chronic liver disease and 53 of 89 (60%) with rheumatoid arthritis serum samples. High titres were found only in rheumatoid arthritis and type 1 autoimmune hepatitis. No clinical (in particular rheumatological manifestations), biochemical or immunoserological differences were detectable between antibodies against cyclic citrullinated peptide positive and negative type 1 autoimmune hepatitis sera, with the exception of rheumatoid factor, always negative in the positive ones.

CONCLUSIONS

Antibodies against cyclic citrullinated peptide can be detected in a subgroup of patients with type 1 autoimmune hepatitis. They might be part of the wide range of autoantibody production characteristic of this condition and/or, less probably, be predictive of future rheumatoid arthritis development.

Clinical features of type 1 autoimmune hepatitis in elderly Italian patients

BACKGROUND

The usual onset of type 1 autoimmune hepatitis occurs at puberty or around menopause, whereas disease presentation in the advanced age is less often reported.

AIM

To assess the clinical, immunological and histological features of Type 1 autoimmune hepatitis in elderly Italian patients.

METHODS

We assessed, at diagnosis, the clinical and immunological features of 76 consecutive Italian patients with type 1 autoimmune hepatitis, focusing particularly on a subgroup of 20 patients presenting at > or = 65 years (females 95%, median age 72 years, range 65-82).

RESULTS

In comparison with the younger group, at the time of autoimmune hepatitis diagnosis, elderly Italian patients are more often asymptomatic (25% vs. 7%; P = 0.04), are more frequently positive for antinuclear autoantibodies (95% vs. 52%; P = 0.0004) and HLA-DR4 (45% vs. 18%; P = 0.03); among the extra-hepatic manifestations, autoimmune thyroid disorders are prevalent in the elderly group (25% vs. 5%; P = 0.02). However, no difference was observed in the histological/biochemical expression of the liver disease and response to immunosuppression.

CONCLUSIONS

In elderly Italian patients, autoimmune hepatitis has typical serological and genetic characteristics, is more frequently asymptomatic, although prognosis and response to therapy is similar to that of younger patients. As a concomitant autoimmune thyroid disorder is common, autoimmune hepatitis should be suspected and investigated in elderly patients with autoimmune thyroid disorder and abnormal liver function tests.

Anti-actin IgA antibodies in severe coeliac disease

Anti-actin IgA antibodies have been found in sera of coeliacs. Our aim was to define the prevalence and clinical significance of anti-actin IgA in coeliacs before and after gluten withdrawal. One hundred and two biopsy-proven coeliacs, 95 disease controls and 50 blood donors were studied. Anti-actin IgA were evaluated by different methods: (a) antimicrofilament positivity on HEp-2 cells and on cultured fibroblasts by immunofluorescence; (b) anti-actin positivity by enzyme-linked immuosorbent assay (ELISA); and (c) presence of the tubular/glomerular pattern of anti-smooth muscle antibodies on rat kidney sections by immunofluorescence. Antimicrofilament IgA were present in 27% of coeliacs and in none of the controls. Antimicrofilament antibodies were found in 25 of 54 (46%) coeliacs with severe villous atrophy and in three of 48 (6%) with mild damage (P < 0.0001). In the 20 patients tested, antimicrofilaments IgA disappeared after gluten withdrawal in accordance with histological recovery. Our study shows a significant correlation between antimicrofilament IgA and the severity of intestinal damage in untreated coeliacs. The disappearance of antimicrofilament IgA after gluten withdrawal predicts the normalization of intestinal mucosa and could be considered a useful tool in the follow-up of severe coeliac disease.

Type 1 autoimmune hepatitis: patterns of clinical presentation and differential diagnosis of the 'acute' type

BACKGROUND

Autoimmune hepatitis (AIH) has three different presentations: chronic, acute and asymptomatic.

AIM

To evaluate AIH presentation in Italian patients and investigate criteria that differentiate between acute-type AIH and acute viral hepatitis.

DESIGN

Prospective observational study.

METHODS

Eighty-six consecutive patients with type 1 AIH and 41 with acute viral hepatitis (controls) were studied. 'Acute' AIH was defined as recent-onset (<30 days) symptoms (jaundice and/or fatigue and/or fever) with marked alterations in serum liver tests; the 'asymptomatic' pattern as the occasional detection of liver abnormalities, and the 'chronic' pattern as the presence of signs and/or symptoms of long-lasting liver disease.

RESULTS

Of 86 AIH patients, 59 (68%) presented with the chronic pattern, 22 (26%) with the acute pattern, and 5 (6%) were asymptomatic. 'Acute' patients had higher AST, ALT and bilirubin serum levels (p < 0.0001). No differences were detected with respect to age and serum levels of alkaline phosphatase, gamma-GT, albumin or gamma-globulin. All three groups had similar prevalences of moderate/severe (vs. mild) histological findings and liver cirrhosis. When compared with controls with acute viral hepatitis, 'acute' AIH patients were more often female (82% vs. 24%, p < 0.0001) and had higher serum gamma-globulin levels (26.9 vs. 13.4 g/l, p < 0.0001) and AST/ALT ratio (1.20 vs. 0.61, p < 0.0001).

DISCUSSION

Although in Italy type 1 AIH patients usually present with a chronic pattern, some 25% have an acute presentation resembling that of viral hepatitis. 'Acute' AIH and viral hepatitis can be reliably differentiated by simple parameters such as gender, gamma-globulin serum levels and AST/ALT ratio.

'True' antimitochondrial antibody-negative primary biliary cirrhosis, low sensitivity of the routine assays, or both?

Anti-mitochondrial antibody (AMA) is considered the serological hallmark of primary biliary cirrhosis (PBC), but may be missing in a proportion of these patients. We assessed sensitivity and specificity of the currently available techniques for AMA detection in a large series of PBC patients and controls, and analysed their clinical and immunological features according to the AMA status. By indirect immunofluorescence on rat tissue sections and HEp-2 cells, Western immunoblot with bovine submitochondrial particles, and two ELISAs with AMA-specific recombinant proteins, we evaluated the presence of AMA in 127 PBC patients, 166 patients with type 1 autoimmune hepatitis and 100 with non alcoholic fatty liver disease. In PBC patients Western immunoblot detects AMA significantly more often than indirect immunofluorescence on HEp-2 cells (85%versus 72%, P = 0.02) or rodent tissue sections (71%, P = 0.01); both ELISAs are only slightly less sensitive than Western immunoblot (81% and 78%). Ten patients with non alcoholic fatty liver disease were AMA-positive by indirect immunofluorescence, but none recognized AMA-specific epitopes in Western immunoblot or in ELISAs. Twelve patients with type 1 autoimmune hepatitis were AMA-positive by indirect immunofluorescence, but only 6 (3.6%) reacted by Western immunoblot and ELISAs. Western immunoblot or ELISA should be regarded as first-line assay for the detection of AMA. Up to 15% of PBC patients are consistently AMA-negative, yet they share the same clinical, biochemical and histological features of AMA-positive PBC. Detection of AMA in type 1 autoimmune hepatitis might identify a subset of patients at risk of developing a hepatitic/cholestatic syndrome.

Prevalence of non-organ specific autoantibodies in HCV-infected subjects in the general population

The significance of non-organ specific antibodies (NOSAs) in HCV-related chronic hepatitis is largely unclear. In this study we evaluated the prevalence of NOSAs in a non-selected population of HCV-infected subjects. One hundred and seventy anti-HCV positive and 192 anti-HCV negative sex and age-matched subjects (median age 64 years, range 7-91 years, female 68%) enrolled from the general population of a small Italian town were evaluated for NOSAs by indirect immunofluorescence on rat tissue sections and HEp-2 cells, and by counterimmunoelectrophoresis with thymus and spleen extracts as the antigen source. One hundred and sixty-three (96%) HCV-infected subjects had normal ALT serum levels and no evidence of liver disease. NOSAs were found in 31 out of 170 (18%) anti-HCV positive subjects and in 20 out of 192 (10%) controls (P = NS), with similar median titre (1:40) and range (1:40 to 1:160). Neither liver/kidney microsomal antibody type 1 nor antiactin reactivity were detected. No significant association between NOSAs and HCV genotypes was observed. In the general population, HCV-infected subjects and healthy controls have a similar prevalence of NOSAs. Without continuous liver damage HCV infection is unlikely to induce the appearance of NOSAs.

Anti-multiple nuclear dots (anti-MND) and anti-SP100 antibodies in hepatic and rheumatological disorders

Multiple nuclear dots pattern has been described in primary biliary cirrhosis and, less often, in rheumatological disorders. Sp100 is the major antigen of multiple nuclear dots. We evaluated prevalence and diagnostic significance of multiple nuclear dots and anti-Sp100 reactivity both in hepatic and rheumatological diseases. A series of 283 consecutive liver patients (89 primary biliary cirrhosis, 12 primary sclerosing cholangitis, 85 autoimmune hepatitis, 97 hepatitis C virus-related chronic liver disease) and of 89 consecutive rheumatological cases were evaluated. Presence of multiple nuclear dots was assessed by indirect immunofluorescence on HEp-2 cells, anti-Sp100 reactivity by ELISA with recombinant protein. Multiple nuclear dots were detected in 20 patients (7%) with liver disease (of whom 15 with primary biliary cirrhosis), and in eight patients (9%) with rheumatological disorders. Anti-Sp100 was detected in 45 liver patients (16%), of whom 30 with primary biliary cirrhosis, but in only two with rheumatological disorders (2%) (P =0.0004). The concordance between multiple nuclear dots and anti-Sp100 in liver and rheumatological patients was 90% and 25% (P=0.0018), respectively. Among 89 consecutive patients with primary biliary cirrhosis, multiple nuclear dots and anti-Sp100 were present in 17% and 34%, respectively (P=0.0152). Anti-Sp100 positivity was associated with older age and higher gamma-globulin levels. Multiple nuclear dots are similarly observed in liver and rheumatological patients. In contrast, anti-Sp100 is more frequent in liver patients and is significantly more often detected in primary biliary cirrhosis, of which it can be regarded as a highly specific serological marker. The antigenic target of multiple nuclear dots in most rheumatological patients is other than Sp100.

Antilactoferrin antibodies in autoimmune liver disease

Antilactoferrin antibodies have been reported in patients with several autoimmune disorders, including primary biliary cirrhosis, autoimmune hepatitis and autoimmune cholangitis. We investigated the prevalence and the clinical significance of such autoreactivity in patients with autoimmune and viral chronic liver disease. Sera from 39 patients with autoimmune hepatitis, 51 with primary biliary cirrhosis, 17 with autoimmune cholangitis, 24 with primary sclerosing cholangitis and 28 with HCV-related chronic hepatitis were studied. Positivity for antilactoferrin antibodies was evaluated by Western immunoblotting with purified human lactoferrin. Antilactoferrin antibodies were detected more often in autoimmune liver disorders (25% autoimmune hepatitis, 25% primary biliary cirrhosis, 35% autoimmune cholangitis, 29% primary sclerosing cholangitis) than in HCV-related chronic hepatitis (3.5%, P < 0.02 versus all). Positivity for antilactoferrin antibodies was not associated with a particular clinical or biochemical profile of the underlying liver disease. No correlation was observed between antilactoferrin reactivity and perinuclear antineutrophil cytoplasmic antibodies. Antilactoferrin antibodies are present significantly more often in autoimmune than in viral liver disorders, but they cannot be considered the serological marker of a specific autoimmune liver disease.

Prevalence of non-organ-specific autoantibodies and chronic liver disease in the general population: a nested case-control study of the Dionysos cohort

BACKGROUND

Several retrospective and prospective studies report an increased prevalence of non-organ-specific autoantibodies (NOSAs) in patients with hepatitis C virus (HCV) related chronic liver disease (CLD). Some of the data so far available are controversial and the true prevalence of NOSAs in the general population is still not known.

AIM

To explore the prevalence of NOSAs, their relation to different HCV genotypes, and the presence and severity of CLD in the general population of Northern Italy.

PATIENTS

All 226 anti-HCV positive and 87 hepatitis B surface antigen (HBsAg) positive patients of the Dionysos cohort study were analysed and compared with sex and age matched cases (226) negative for both anti-HCV antibody and HBsAg selected from the same cohort.

METHODS

Sera tested for the presence of NOSAs (anti-nuclear antibody (ANA), anti-smooth muscle antibody (SMA), and anti-liver/kidney microsomes type 1 antibody (LKM1)) were screened by indirect immunofluorescence at a 1:40 serum dilution. HCV RNA and HCV genotypes were also determined by nested polymerase chain reaction (PCR) of the 5' non-coding region and by PCR amplification of the core region with type specific primers.

RESULTS

The overall prevalence of NOSA reactivity was significantly higher in anti-HCV positive subjects than in both normal and pathological controls (25% v 6% and 7% respectively, p<0.05). ANA, SMA, and LKM1 occurred in 16, 10, and 1. 3% of cases respectively. No specific association between NOSAs and a specific HCV genotype was found. NOSAs were found more often associated with more than one genotype (35.7%) and with untypable genotypes (34.6%), although the association was not statistically significant. NOSAs were associated with HCV RNA and CLD but not with the presence of cirrhosis and/or hepatocellular carcinoma. On univariate analysis, NOSA reactivity was independently associated with abnormal alanine aminotransferase (p<0.01) and gamma-glutamyltranspeptidase levels (p<0.05). The risk for the presence of NOSAs was 5.1 times higher in anti-HCV subjects than in controls.

CONCLUSIONS

In the general population the prevalence of NOSAs is higher in anti-HCV positive subjects than in normal or disease controls. Moreover NOSAs are associated with CLD and with a more active disease in terms of alanine aminotransferase activity.

Auto-antibodies in hepatitis C

Hepatitis C virus (HCV) has been implicated in the development of a variety of autoimmune phenomena, some of which are well documented and include a panel of auto-antibodies shared with autoimmune hepatitis (AIH). Anti-nuclear (ANA) and smooth muscle (SMA) antibodies (markers of AIH type 1 [AIH-1]), have been demonstrated in 9-38% and 5-91% of cases respectively, whereas anti-liver/kidney microsomal type 1 (anti-LKM-1) and anti-liver cytosol type 1 antibodies (anti-LC1) (markers of AIH type 2 [AIH-2]), are definitely rarer, especially in adults. The presence of these auto-reactivities in chronic hepatitis C generates clinical overlaps and dilemmas in the correct classification and treatment of such patients. The immunopathological characterization of the auto-antibodies, anti-nuclear and smooth muscle antibodies in particular, combined with internationally defined criteria for the diagnosis of AIH is helpful in this clinical process. Thyroid auto-antibodies and cryoprecitable rheumatoid factors are also commonly detected in hepatitis C, while the occurrence of other auto-antibodies still awaits confirmation.

Frequency and significance of anti-gliadin and anti-endomysial antibodies in autoimmune hepatitis

Celiac disease has been associated with autoimmune disorders, but its frequency in autoimmune hepatitis is unknown. Sera from 157 patients with type 1 autoimmune hepatitis, 24 patients with type 2 autoimmune hepatitis, 62 patients with primary biliary cirrhosis, 30 patients with chronic hepatitis B, and 80 patients with chronic hepatitis C were tested for immunoglobulin A anti-endomysial antibodies by indirect immunofluorescence and immunoglobulin A and G antibodies to gliadin by enzyme immunoassay. Duodenal biopsy evaluation was recommended in patients seropositive for immunoglobulin A anti-endomysial antibodies. Immunoglobulin A anti-endomysial antibodies were present in eight of the 181 patients with autoimmune hepatitis (4%), including six with type 1 disease (4%) and two with type 2 disease (8%). Immunoglobulin A antibodies to gliadin were found in six of these eight patients, but they were also present in two others, including one patient with chronic hepatitis C. Five of the eight patients with immunoglobulin A antiendomysial antibodies, including three patients with no gastrointestinal symptoms, had duodenal biopsies and subtotal villous atrophy was present in all of them. No patient with primary biliary cirrhosis or chronic viral hepatitis had antiendomysial antibodies. The presence of celiac disease in autoimmune hepatitis is high (at least one in 36 patients) and it is predominantly asymptomatic. Screening with anti-endomysial and anti-gliadin antibodies should be performed and results confirmed with intestinal biopsy.

Frequency and significance of anti-gliadin and anti-endomysial antibodies in autoimmune hepatitis

Celiac disease has been associated with autoimmune disorders, but its frequency in autoimmune hepatitis is unknown. Sera from 157 patients with type 1 autoimmune hepatitis, 24 patients with type 2 autoimmune hepatitis, 62 patients with primary biliary cirrhosis, 30 patients with chronic hepatitis B, and 80 patients with chronic hepatitis C were tested for immunoglobulin A anti-endomysial antibodies by indirect immunofluorescence and immunoglobulin A and G antibodies to gliadin by enzyme immunoassay. Duodenal biopsy evaluation was recommended in patients seropositive for immunoglobulin A anti-endomysial antibodies. Immunoglobulin A anti-endomysial antibodies were present in eight of the 181 patients with autoimmune hepatitis (4%), including six with type 1 disease (4%) and two with type 2 disease (8%). Immunoglobulin A antibodies to gliadin were found in six of these eight patients, but they were also present in two others, including one patient with chronic hepatitis C. Five of the eight patients with immunoglobulin A antiendomysial antibodies, including three patients with no gastrointestinal symptoms, had duodenal biopsies and subtotal villous atrophy was present in all of them. No patient with primary biliary cirrhosis or chronic viral hepatitis had antiendomysial antibodies. The presence of celiac disease in autoimmune hepatitis is high (at least one in 36 patients) and it is predominantly asymptomatic. Screening with anti-endomysial and anti-gliadin antibodies should be performed and results confirmed with intestinal biopsy.

Serum autoantibodies in chronic hepatitis C: comparison with autoimmune hepatitis and impact on the disease profile

Antibodies to nuclei (ANA), smooth muscle (SMA), and liver/kidney microsomes type 1 (anti-LKM1) may occur in chronic hepatitis C. Distinct subspecificities, including ANA with the homogeneous pattern (ANA-H) and SMA with antiactin specificity (SMA-AA), are found in autoimmune hepatitis (AIH). This study was performed to characterize the hepatitis C virus (HCV)-associated autoantibodies and to evaluate their influence on the profile of the disease. Two hundred ninety consecutive patients with chronic hepatitis C and 35 control cases with AIH were screened for autoantibodies by indirect immunofluorescence (IFL) at 1:40 serum dilution. The ANA pattern was defined by IFL on HEp-2 cells and the SMA-AA identified by the presence of at least two of the following elements: 1) SMA(T) or SMA(G) pattern by IFL on kidney sections; 2) XR1 precipitating system by counterimmunoelectrophoresis; or 3) typical pattern by IFL on liver sections from phalloidin-intoxicated rats. ANA, SMA, and anti-LKM1 occurred in 9%, 20%, and 6% of chronic hepatitis C cases, respectively. The overall prevalence of autoantibodies was 30% (87 of 290). Compared with AIH, HCV-associated ANA and SMA exhibited ANA-H and SMA-AA at a lower prevalence (38% vs. 71%, P = .04 and 8% vs. 87%, P < .000001, respectively) and had a lower median titer (1:80 vs. 1:320, P < .001 and 1:40 vs. 1:320, P < .000001, respectively). The concomitant positivity for ANA-H and SMA-AA was detected in none of the HCV cases, but in 46% of AIH sera (P < .000001). Two parameters were independently associated with the autoantibodies in chronic hepatitis C: high alanine transaminase (ALT) serum levels (F = 14.04) and female gender (F = 5.03). At the univariate analysis, patients with autoantibodies had a more severe portal-periportal necroinflammation (median Scheuer's score: 2.05 vs. 1.64, P = .003). The presence of autoantibodies did not influence the response to interferon (IFN). In chronic hepatitis C, serum autoantibodies are common, but their subspecificities are distinct from those occurring in AIH. Whereas the absence of ANA-H and/or SMA-AA does not exclude AIH, the characterization of ANA and SMA may help to discriminate between the two conditions. As compared with the seronegative counterpart, autoantibody-positive chronic hepatitis C is more common in females and exhibits a more severe biochemical and histological activity. The response to IFN therapy, however, is similar.

Antinuclear antibodies and patterns of nuclear immunofluorescence in type 1 autoimmune hepatitis

To determine the significance of antinuclear antibodies and their patterns of indirect immunofluorescence in type 1 autoimmune hepatitis, sera from 99 patients were evaluated. Patients with antinuclear antibodies had a lower frequency of liver transplantation (6% vs 22%, P = 0.04) than seronegative patients. They were also more commonly HLA-DR4-positive than seronegative patients (56% vs 30%, P = 0.05) and normal subjects (56% vs 30%, P = 0.004). The 42 patients with antinuclear antibodies and a diffuse pattern of indirect immunofluorescence had higher serum titers of ANA (serum titers > or = 1:500, 71% vs 14%, P < 0.0001) and SMA (serum titers > or = 1:500, 69% vs 27%, P = 0.003) than the 22 patients with antinuclear antibodies and a speckled pattern. These patients, however, were otherwise not distinguished by clinical features and treatment response. Patients with a speckled pattern had A1-B8-DR3 more frequently than patients with a diffuse pattern (65% vs 23%, P = 0.005) and normal subjects (65% vs 13%, P < 0.0001), but they had no other salient features. We conclude that patients with antinuclear antibodies have a better long-term prognosis than seronegative patients, and they have HLA-DR4 more commonly. The patterns of indirect immunofluorescence associated with ANA positivity have no practical clinical implications.

Anti-neutrophil cytoplasmic antibodies in type 1 and 2 autoimmune hepatitis

Perinuclear anti-neutrophil cytoplasmic antibodies (pANCA) have been recently defined as the most sensitive autoantibody of type 1 autoimmune hepatitis (AIH-1). Their prevalence in type 2 autoimmune hepatitis (AIH-2) has not yet been evaluated. The aim of the present study was to verify the association of pANCA with AIH-1 in an Italian series and to investigate the prevalence of the antibodies in AIH-2 and in proper control groups represented by cases of chronic hepatitis C (CH-C) with similar autoimmune features. pANCA were found in 30 of 46 (65%) AIH-1 and in 4 of 30 (13%) ANA/smooth muscle antibody (SMA) positive CH-C (P = .0000006). Nineteen AIH-2, 29 liver kidney microsomal antibody type 1/liver cytosol antibody type 1 (LKM1/LC1) positive CH-C cases and 50 healthy controls were all negative. In AIH-1, pANCA were significantly (P = .009) more frequent in males (8 of 9, 89%) than in females (22 of 37, 59%). All pANCA positive sera showed SMA of the antiactin type. The present data confirm that pANCA, although less prevalent in our series than in other reports, do associate with AIH-1 also in the Mediterranean area and show that it can identify a small subgroup (13%) of ANA/SMA positive chronic hepatitis C, in which autoimmune reactions might play a more relevant role than viral infection. They also show the antibodies are absent in AIH-2. In conclusion, pANCA appear to be mutually exclusive of LKM1 positivity, either hepatitis C virus-related or not, thus representing a further valuable tool to differentiate the two types of autoimmune hepatitis.

Ultrasound-detected abdominal lymphadenopathy in chronic hepatitis C: high frequency and relationship with viremia

BACKGROUND/AIMS

This study aimed to investigate the prevalence and significance of ultrasound-detected deep abdominal lymphadenopathy in chronic hepatitis due to C virus.

METHODS

One hundred and thirty-four consecutive patients with various liver disorders were examined with portable real-time equipment.

RESULTS

In 25 (19%), the procedure failed because of excessive meteorism. Deep nodes, mainly located in the hepato-duodenal ligament, were detected in 62 of the remaining 109 patients (57%), reaching the highest prevalences in primary biliary cirrhosis (5/7, 71%), chronic hepatitis C (44/66, 67%) and autoimmune hepatitis type 1 (2/3, 67%). For all patients, including those with liver diseases with multiple etiology, lymphadenopathy was more frequent in anti-HCV positive (51/81, 63%) than in negative cases (11/28, 39% p=0.02). In chronic hepatitis C, serum HCV RNA was detected by nested polymerase chain reaction in all 31 patients with, but in only 75% (12/16) of those without nodes (p=0.018). No other distinct clinical or laboratory feature was found in association with lymphadenopathy; in particular, its incidence was similar in cases with and without liver cirrhosis.

CONCLUSIONS

Enlarged deep abdominal lymph nodes are frequently detected by ultrasound in patients with chronic hepatitis C. This feature may be of diagnostic utility, especially in early cases, when liver cirrhosis has not yet developed and therefore no other ultrasound sign of the underlying disease can be detected. Lymphadenopathy may be of biological significance, marking hepatitis C virus infection in a replicative, viremic stage. These observations support the existence of a close interaction between hepatitis C virus and the lymphatic system.

Frequency and significance of antibodies to actin in type 1 autoimmune hepatitis

Antibodies to actin have been proposed as diagnostic markers for type 1 autoimmune hepatitis. Our aims were to determine 1) if testing for antibodies to actin is superior to testing for smooth muscle antibodies (SMA); 2) if these antibodies identify patients with distinctive clinical features; and 3) if the production of antibodies to actin is associated with genetic risk factors for autoimmune hepatitis. Sera from 99 patients with type 1 autoimmune hepatitis were tested. The frequencies of HLA B8, DR3, DR4, and A1-B8-DR3 in patient subsets were compared with those in 80 normal subjects. Seventy-three patients (74%) had antibodies to actin. Antibodies to actin were found more commonly in patients with SMA than in patients without them (86% vs. 7%, P < .0001). Screening only for antibodies to actin and antinuclear antibodies (ANA) failed to establish the diagnosis of autoimmune hepatitis in 5 patients. Patients with antibodies to actin were younger than seronegative patients. They were also more commonly DR3-positive than normal subjects and more frequently B8-positive than patients with non-actin-associated SMA (49% vs. 0%, P = .004). Only patients with antibodies to actin died of liver failure (6% vs. 0%), and 10 of 11 patients requiring liver transplantation were seropositive for these antibodies. Indeed, death and liver transplantation occurred more frequently in these patients than in actin-negative patients with ANA (19% vs. 0%, P = .03). We conclude that routine screening for antibodies to actin may miss patients with type 1 autoimmune hepatitis. Antibodies to actin are associated with HLA B8 and DR3, and they identify patients with a poor prognosis.

Impact of international autoimmune hepatitis group scoring system in definition of autoimmune hepatitis. An Italian experience

We have reclassified 110 patients with autoantibody-positive cryptogenic chronic hepatitis according tot he aggregate scoring system proposed by the International Autoimmune Hepatitis Group for signs of hepatitis C virus (HCV) infection and the newly proposed terminology of "unclassified" chronic hepatitis. Anti-HCV and HCV viremia were assessed by second-generation assays and reverse transcription-polymerase chain reaction. Immunomorphological and immunochemical characterizations of antinuclear, smooth, muscle, liver-kidney microsomal type 1, and liver cytosol type 1 autoantibodies were also performed. All 45 anti-HCV negative patients fulfilled the score criteria for the diagnosis of "definite" or "probable" autoimmune hepatitis (AIH). Eight anti-HCV-positive cases reached the score of "probable" AIH, whereas the remaining 57 cases were diagnosed as unclassified chronic hepatitis. The scoring system allows the correct identification of all autoimmune cases without HCV infection. Autoimmune hepatitis runs a more severe disease course than unclassified chronic hepatitis, whose clinical and histological features are similar to those of autoantibody-negative chronic hepatitis C.

Detection of anti-liver cytosol antibody type 1 (anti-LC1) by immunodiffusion, counterimmunoelectrophoresis and immunoblotting: comparison of different techniques

Liver cytosol specific antibody type 1 (anti-LC1) was first described in a proportion of patients with liver/kidney microsomal antibody type 1 (anti-LKM1)-positive autoimmune hepatitis (AIH) and is routinely evaluated by immunodiffusion (ID). Using human liver cytosol as the source of antigen, we have used ID, counterimmunoelectrophoresis (CIE) and immunoblotting (IB), to test sera from 167 patients with documented chronic liver diseases of different etiology. 15 patients had antinuclear antibody (ANA) and/or smooth muscle antibody (SMA)-positive AIH, 13 had anti-LKM1-positive AIH, four had ANA/SMA/anti-LKM1-negative AIH, 76 had anti-LKM1-positive hepatitis C (recently renamed unclassified chronic hepatitis-UCH), 40 had chronic hepatitis C, 15 had chronic hepatitis B, and 4 had chronic hepatitis D. A precipitin line of identity with an anti-LC1 reference serum was detected both by ID and CIE in 16 patients: six with anti-LKM1-positive 'definite' AIH, four with ANA/SMA/anti-LKM1-negative 'definite' AIH, and six with anti-LKM1-positive UCH. By IB, 14 out of the 16 anti-LC1-positive sera (87.5%) reacted with a 58 kDa human liver cytosolic polypeptide, whereas three out of 16 (19%) recognised an additional 60 kDa band. Compared to ID, CIE is more economical in terms of both time and reagents and provides more clear-cut results. The 58 kDa reactivity by IB was detectable in nearly all CIE/ID anti-LC1-positive patients, was not found among CIE/ID anti-LC1-negative patients. In conclusion, CIE is the ideal screening test for the detection of anti-LC1, an autoantibody that can be regarded as an additional serological marker of AIH and is especially useful in ANA/SMA/anti-LKM1 negative cases.

Liver cytosolic 1 antigen-antibody system in type 2 autoimmune hepatitis and hepatitis C virus infection

Within the multiform liver/kidney microsomal (LKM) family, a subgroup of sera that reacts with a liver cytosolic (LC) protein has been isolated and the new antigen-antibody system is called LC1. Unlike LKM antibody type 1 (anti-LKM1), anti-LC1 is said to be unrelated to hepatitis C virus (HCV) infection and has therefore been proposed as a marker of 'true' autoimmune hepatitis type 2. Altogether 100 LKM1 positive sera were tested by immunodiffusion (ID). Twenty five gave a precipitation line with human liver cytosol; 17 of the 25 also reacted with rat liver cytosol. Thirteen of the 25 sera were anti-HCV positive by second generation ELISA: anti-HCV positive patients were significantly older (p < 0.001) and tended to have less active disease. No difference in anti-LC1 titre or ID immunoreactivity was found between anti-LC1/anti-HCV positive and anti-LC1/anti-HCV negative cases. In Western blotting experiments, 14 of 24 ID positive sera recognised a 58 kD protein of the human cytosolic fraction and 11 gave a similar reactivity when tested with human microsomes, suggesting the presence of the LC1 target antigen also in the microsomal preparation. Western blotting reactivity was similar for both anti-HCV positive and negative sera. These data confirm the existence of the LC1 antigen-antibody system that partially overlaps with LKM1, and that it is an additional marker of juvenile autoimmune hepatitis type 2. It does not, however, discriminate between patients with and without HCV infection.

Hepatocellular expression of HLA-A, B, C molecules predicts primary response to interferon in patients with chronic hepatitis C

Primary response rate to alpha-interferon (IFN) is about 50% in patients with chronic hepatitis C. Criteria for predicting a positive primary response are lacking. HLA-A,B,C molecule expression is known to be stimulated by viral infections. In 36 consecutive interferon-treated anti-HCV positive patients with an available frozen liver biopsy sample, the predictive value of liver HLA-A,B,C expression, and of histologic, clinical, and biochemical parameters was evaluated. Response to treatment was defined by normalization of transaminases, and disappearance of serum HCV-RNA within 3 months. According to these criteria, 17 patients were classified as nonresponders and 19 were classified as responders. The pattern of HLA-A,B,C hepatocellular positivity varied from normal (negative or occasional faint staining of hepatocellular membranes) to diffuse, strong "honeycomb" positivity. The highest scores of positivity were found in nonresponder patients. The discriminant capacity of HLA-A,B,C scores of positivity was compared with clinical, biochemical and histologic parameters by discriminant analysis. HLA-A,B,C expression was found to be the main discriminant parameter, in addition to alkaline phosphate (ALP) and gamma-glutamyl-transpeptidase (GGT) which added little additional information. The higher hepatocellular expression of class I MHC molecules in nonresponder cases may reflect a different viral effect on hepatocytes, which is induced by different HCV genotypes or levels of viremia. From a clinical point of view, the pretreatment HLA-A,B,C pattern of positivity represents a powerful tool in the selection of patients for interferon treatment.

Interferon therapy in liver/kidney microsomal antibody type 1-positive patients with chronic hepatitis C

The association between liver/kidney microsomal antibody type 1 and adult cases of hepatitis C virus-related chronic liver disease has been firmly established. In the presence of both markers, evidence of autoimmunity (liver/kidney microsomal antibody type 1) and actual viremia (serum HCV RNA), the therapeutic dilemma arises between steroids, which are beneficial to autoimmune but deleterious to viral diseases, and interferon-alpha, which may exacerbate an autoimmune disorder. Six patients with liver/kidney microsomal antibody type 1 and serum HCV RNA were given interferon-alpha: three showed a response pattern similar to that observed in autoantibody-negative chronic hepatitis C cases; the other three developed a sharp transaminase peak, which was not followed by HCV RNA clearance. Considering the brisk flare-up of liver cell necrosis, interferon-alpha treatment proved to be dangerous in the above three liver/kidney microsomal antibody type 1/HCV RNA positive cases. Subsequent steroid administration reduced alanine aminotransferase peaks, but may be harmful in viral infections. Therapeutic alternatives are needed: they will probably include pure antivirals (exerting no immunostimulatory effects) with or without immunosuppressive drugs.

Testing for hepatitis C virus sequences in peripheral blood mononuclear cells of patients with chronic hepatitis C in the absence of serum hepatitis C virus RNA

Hepatitis C virus (HCV) is able to replicate in peripheral blood mononuclear cells (PBMC) of HCV-infected patients. Few data are available on PBMC testing for HCV RNA in serum HCV RNA negative patients, positive for anti-HCV and with histological evidence of chronic hepatitis. Twenty such patients were studied; of these, 11 were tested during interferon alpha (IFN) treatment, at the time of serum HCV RNA clearance and ALT normalisation: only one was found to be positive for HCV sequences in PBMC. Within 3 months of IFN withdrawal all 11 patients relapsed with high ALT and recurrence of serum HCV RNA. Of nine serum HCV RNA negative patients with chronic hepatitis C who were not receiving IFN when tested (four untreated patients and five patients who had already completed IFN schedule), PBMC HCV RNA was detected in four. Evidence of active HCV replication (presence of the minus strand genome) in PBMC was also observed in two cases. Thus, five of the 20 patients without detectable serum HCV RNA turned out to be carriers of HCV sequences in PBMC. These data indicate that: 1. PBMC are an extrahepatic replication site of HCV; this is true also in the absence of serum HCV RNA; 2. the role of PBMC as a "viral reservoir" after IFN-induced serum HCV RNA clearance is questioned; 3. the absence of both serum and PBMC HCV RNA in patients under IFN is not predictive of sustained viral loss; 4. testing for PBMC viral sequences might enhance the chances of detecting HCV infection.

Increased risk of hepatocellular carcinoma development in patients with cirrhosis and with high hepatocellular proliferation

The immunohistochemical determination of the accessory protein of DNA-polymerase delta (PCNA), a marker of an early S-phase of the cell cycle, was used to evaluate cell proliferation retrospectively in formalin-fixed, paraffin-embedded liver biopsy sections in a group of patients with cirrhosis of similar age and duration of follow up, and with no evidence of hepatocellular carcinoma (41), including 17 patients with and 24 without hepatocellular carcinoma appearance during follow up. Proliferation was expressed as total (PCNA-TOT) and strongly (PCNA-STRO) positive nuclei per 1000 hepatocytes. The presence of dysplasia was also recorded. Histological findings and biochemical data, at the time of liver biopsy, were compared in the two groups. While total PCNA positivities were not significantly different in the two groups, strong reactivity was significantly higher in patients who eventually developed hepato-cellular carcinoma (median 0.7 vs 2.6). Univariate analysis of histological and biochemical data at the time of biopsy, followed by a stepwise regression study, showed that the significant parameters for a time-dependent disease-free state were, in decreasing order: cholesterol, PCNA-STRO, PCNA-TOT and alpha foeto-protein. Other clinical, biochemical and histological parameters, including dysplasia, provided no further information. From these data, hepatocellular proliferation can be evaluated in patients with cirrhosis with a currently available technique. Patients with high cell proliferation are at increased risk of developing hepatocellular carcinoma and may require differentiated follow up.

Abdominal lymphadenopathy detected by ultrasonography in HIV-1 infection: prevalence and significance

By using abdominal ultrasonography (UlS), deep nodes were detected in 41 of 85 (48%) HIV-1 positive subjects, most of them heroin addicts, but in none of 85 healthy HIV-negative controls. Computerized tomography, performed in 10 cases of lymphadenopathy, invariably confirmed the UlS findings. Prevalence [asymptomatic carriers: 8/15 (53%); PGL patients: 8/18 (44%); ARC: 13/27 (48%); AIDS: 12/25 (48%)], number, size, and site of deep nodes were comparable among the different CDC groups. No correlation was found between abdominal and superficial lymphadenopathy. Median serum concentrations of gammaglobulins (g/dl) and IgG (mg/dl) were higher in patients with than without deep nodes (2.25 vs 1.87 and 2540 vs 1900, respectively) (p < 0.01) as well as in cases with than without superficial nodes (2.15 vs 1.80 and 2340 vs 1941, respectively) (p < 0.05). Abdominal lymphadenopathy occurred during all stages of HIV infection even in asymptomatic carriers: this should be considered in the differential diagnosis of UlS-detected deep nodes. Enlargement of either deep or superficial nodes seems to reflect a state of polyclonal B cell activation.

Serum autoantibodies and the diagnosis of type-1 autoimmune hepatitis in Italy: a reappraisal at the light of hepatitis C virus infection

Antinuclear antibodies with the homogeneous pattern (ANA-H) and smooth muscle antibodies with antiactin specificity (SMA-AA) are regarded as the serum markers of type-1 autoimmune chronic hepatitis. Their diagnostic relevance, however, has been questioned recently after the detection of signs of hepatitis C virus infection in autoimmune chronic hepatitis patients. To further evaluate this point, antihepatitis C virus antibodies were sought by two second generation assays (ELISA 2 and RIBA 2) in 100 Italian patients with chronic liver disease of unknown aetiology, including 46 with (autoimmune chronic hepatitis) and 54 without the above antibodies (cryptogenic). By ELISA 2, antihepatitis C virus, although significantly prevalent in cryptogenic (83%), were found also in a substantial proportion of autoimmune chronic hepatitis patients (46%) (p < 0.0001), their occurrence was confirmed by RIBA 2 in almost all cases (96% and 86%, respectively). Autoimmune patients with either ANA-H or SMA-AA exhibited similar antihepatitis C virus prevalences (59% and 52%, respectively); by contrast, the eight cases positive for both the autoantibodies were consistently antihepatitis C virus negative. These findings confirm that in countries with high hepatitis C virus circulation (like Italy) an overlap between autoimmune chronic hepatitis and hepatitis C virus infection, reflected by 'true' antihepatitis C virus antibodies, does occur. The detection of ANA-H or SMA-AA, in fact, identifies chronic liver disease patients with a relatively low prevalence of antihepatitis C virus, but does not exclude hepatitis C virus infection. Positive findings for both ANA-H and SMA-AA, however, is an appropriate marker for hepatitis C virus free 'primary' autoimmune chronic hepatitis.

Demonstration of peptide-specific and cross-reactive epitopes in proteins reacting with antimitochondrial antibodies of primary biliary cirrhosis

Recently the main targets of antimitochondrial antibodies (AMA) of primary biliary cirrhosis have been identified as parts of three related mitochondrial multienzyme complexes, namely pyruvate dehydrogenase (PDH), branched chain alpha-ketoacid dehydrogenase (BKDH) and alpha-ketoglutarate dehydrogenase (alpha-KGDH). Usually AMA-positive PBC serum samples show reactivity to more than one of these, raising the question whether they are exclusively different antibodies or are, at least in part, the result of cross-reactive specificities. With Western immunoblotting, four antigens with molecular masses of 74, 52, 51 and 43 kDa, are recognized by PBC sera. In this study, using affinity purified antibodies from mitochondrial proteins immobilized on nitrocellulose blots, we demonstrate the presence of peptide-specific and cross-reactive epitopes in some targets. In particular, at least three different epitopes present in the 74-kDa protein (presumed to by PDH-E2) are also present in the 51-kDa protein (probably PDH-X), and two in the 52-kDa peptide (possibly BCKDH-E2). Moreover, the 43-kDa mitochondrial protein (the identity of which is more problematic) has three epitopes. One of these is also present in the 74-, 52- and 51-kDa proteins, a second in the 74- and 51-kDa, and a third seems to be peptide-specific. These results show that different sera with the same immunoblotting pattern of reactivity can have antibodies with different antigenic specificities and, conversely, that the same specificity can be responsible for more than one band.

Hepatitis C viraemia in adults with type 2 autoimmune hepatitis

Sera from 14 patients with type 2 autoimmune hepatitis (anti-LKM1 positive) were investigated for evidence of hepatitis C virus (HCV) infection. Antibodies to HCV were detected in 13 patients by both commercial and "in-house" ELISAs and also by a second generation recombinant immunoblot assay. Nine of the 13 (69%) anti-HCV positive patients were shown to be viraemic by a polymerase chain reaction-based assay for serum HCV RNA. Neither anti-HCV nor serum HCV RNA were detected in any of 6 controls with primary biliary cirrhosis or in 39 healthy blood donors. These findings strongly suggest a role for HCV in the pathogenesis of type 2 autoimmune hepatitis.

IgA antiendomysial antibody test. A step forward in celiac disease screening

Serum IgA antiendomysial antibodies (EmA) were found in 61 (87%) of 70 adults and children with untreated celiac disease, whereas IgA antigliadin antibodies (AGA) and IgA R1-antireticulin antibodies (R1-ARA) were positive in 71% and 47%, respectively, of the same patients. Two of the nine untreated celiacs negative for IgA EmA showed positivity for IgA AGA. While IgA AGA and R1-ARA disappeared in all the celiacs tested one year after gluten-free diet, IgA EmA persisted at low titer in seven (18%) of these 38 subjects, although the jejunal biopsy showed a complete regrowth of jejunal villi. All the disease control patients as well as the blood donors tested were always negative for the three IgA antibodies. Our results state that the search for both IgA EmA and AGA gives the best results in the screening of celiac disease, since the positivity for at least one of these two antibodies allows identification with a 100% specificity of the 90% of untreated celiac patients.

Anti-nuclear antibodies of primary biliary cirrhosis recognize 78-92-kD and 96-100-kD proteins of nuclear bodies

The specificities of anti-nuclear antibodies (ANA) reacting with multiple nuclear dots (MND-ANA) present in about 15% primary biliary cirrhosis sera were studied by Western blot analysis with nuclear fractions from a human cell line. Reactivity with two broad bands of 78-92 kD and 96-100 kD of the insoluble fraction was present exclusively in MND-ANA-positive sera. Antibodies eluted from these proteins specifically retained the immunofluorescence reactivity of MND-ANA. Immunomorphological analysis by a pre-embedding technique revealed that the antibody specifically binds to nuclear regions resembling in size and number nuclear bodies. Since these structures are absent in immature rate endometrial cell and can be induced by diethylstilbestrol, we tested MND-ANA by immunofluorescence on cryostat sections of uteri from hormone-treated and untreated immature rats. A strong reaction of nuclear dots was observed predominantly in endometrial cells of hormone treated rats. We thus conclude that MND-ANA present in primary biliary cirrhosis sera are directed against 78-92-kD and 96-100-kD nuclear proteins located in nuclear bodies.

Serum non-organ specific autoantibodies in human immunodeficiency virus 1 infection

Serum samples from 66 seropositive subjects (56 with a history of intravenous drug abuse), including asymptomatic carriers and patients with persistent generalised lymphadenopathy (PGL), AIDS related complex (ARC), and AIDS, were tested by indirect immunofluorescence on rat tissue sections and HEp-2 cells for the presence of antibodies to nuclei, smooth muscle, intermediate filaments (anti-IMF) and microfilaments (anti-MF). Counterimmunoelectrophoresis was also used to detect antibodies to extractable nuclear antigens. Smooth muscle antibodies with the V pattern or antinuclear antibodies, mainly of the speckled type, or anti-IMF, occurred in 35 cases, being widely distributed in all groups. Such an autoantibody response resembles the "viral" autoimmunity described in various infectious diseases and in particular that of non-A, non-B post-transfusion hepatitis. Autoantibodies may be of some prognostic relevance, as the prevalence of smooth muscle antibodies V increased as the disease progressed (asymptomatic carriers 20%, those with PGL 29%, those with ARC 47%, and those with AIDS 63%. In the PGL group autoantibody positivity correlated with the presence of skin anergy. The fact that autoantibodies were more frequently detected in patients with circulating immune complexes suggests that these can contain autoantibodies and the corresponding autoantigens.