E T Davies

De-novo autoimmune hepatitis after liver transplantation.

Summary Background Late graft dysfunction that does not result from recognised causes, such as rejection, infection, or vascular or biliary complications, can occur after liver transplantation. We investigated a particular type of unexplained graft dysfunction that is associated with autoimmune features in children who underwent transplantation at our unit between 1991 and 1996. Methods Seven (4%) of 180 liver-transplant recipients developed an unexplained but characteristic form of graft dysfunction (five boys, two girls; median age at presentation 10·3 years, range 2·0–19·4). The median period after surgery was 24 months (6–45). The indications for transplantation had been extrahepatic biliary atresia (four patients), Alagilles syndrome (one), drug-induced acute liver failure (one), and α1-antitrypsin deficiency (one). Four patients were on triple immunosuppression with cyclosporin, azathioprine, and prednisolone; and three were on tacrolimus. Immunoglobulin measurements, autoantibody studies, serological studies, and HLA typing were undertaken. Liver-biopsy samples were taken. Findings Infectious and surgical complications were excluded. Liver-biopsy samples showed the histological changes of chronic hepatitis, including portal and periportal hepatitis with lymphocytes and plasma cells, bridging collapse, and perivenular-cell necrosis without changes typical of acute or chronic rejection. All patients had high concentrations of IgG (median 22 g/L [range 17·2–34·4]) and high titres of autoantibodies. All but one patient responded to prednisolone 2 mg/kg daily and an increase in or addition of azathioprine (1·5 mg/kg daily) within a median of 32 days (7–316). One responder relapsed owing to poor compliance but went into remission after treatment was restored. All six respondents remain in remission on a reduced dose of prednisolone (5–10 mg/day) and 1·5 mg/kg daily azathioprine at a median of 283 days (range 108–730) follow-up. Interpretation Our data show that symptoms of autoimmune hepatitis, which are responsive to the classical treatment for this condition, can appear in liver-transplant patients while they are on anti-rejection immunosuppression. Whether the liver damage in these patients is a form of rejection or the consequence of autoimmune attack has yet to be established.

Reduced monocyte HLA‐DR expression: A novel biomarker of disease severity and outcome in acetaminophen‐induced acute liver failure

Acute liver failure (ALF) shares striking similarities with septic shock where a decrease in HLA‐DR expression on monocytes is associated with disease severity and predicts outcome. We investigated monocyte HLA‐DR expression in ALF in relation to inflammatory mediator levels and clinical outcome. Monocyte HLA‐DR expression was determined in 50 patients with acetaminophen‐induced ALF (AALF) and 20 non–acetaminophen‐induced ALF (NAALF). AALF patients were divided into dead/transplanted (AALF‐NS, n = 26) and spontaneous survivors (AALF‐S, n = 24). Fifty patients with chronic liver disease (CLD) and 50 healthy volunteers served as controls. Monocyte HLA‐DR expression was determined by double‐color flow‐cytometry with monoclonal antibodies detecting HLA‐DR and monocyte specific CD14. Serum levels of interleukin (IL) ‐4, ‐6, ‐10, tumor necrosis factor (TNF)‐α and interferon (IFN)‐γ were concomitantly measured by ELISA. Compared to healthy volunteers (75%) and CLD (67%) monocyte HLA‐DR percentage expression was lower in AALF (15%, P < .001) and NAALF (22 %, P < .001). Compared to AALF‐S, AALF‐NS had lower monocyte HLA‐DR % (11% vs. 36%, P < .001) and higher levels of IL‐4, IL‐6, IL‐10 and TNF‐α (P < .001). HLA‐DR percentage negatively correlated with INR, blood lactate, pH and levels of encephalopathy (r = −0.8 to −0.5, P < .01), IL‐10 (r = −0.8, P < .0001), TNF‐α (r = −0.4, P = .02). HLA‐DR percentage level ≤15% has a 96% sensitivity and 100% specificity and 98% accuracy in predicting poor prognosis. In conclusion, the strong relationship of monocyte HLA‐DR expression with indices of disease severity, mediators of inflammation and outcome indicates a key role for this molecule as a biomarker of disease severity and prognosis. (HEPATOLOGY 2006;44:34–43.)

Prevalence and clinical significance of isotype specific antinuclear antibodies in primary biliary cirrhosis.

Background: Antinuclear antibodies (ANA) giving a rim-like/membranous (RL/M) or a multiple nuclear dot (MND) pattern are highly specific for primary biliary cirrhosis (PBC). Aim and subjects: To assess the prevalence of PBC specific ANAs, their Ig isotype, and their clinical significance in 90 PBC patients from Greece and Spain. Twenty eight patients with chronic hepatitis C, 23 patients with systemic lupus erythematosus, and 17 healthy subjects were studied as controls. Methods: PBC specific ANA reactivity was tested by indirect immunofluorescence using HEp2 cells as substrate and individual Ig class (IgG, IgA, IgM) and IgG subclass (IgG1, IgG2, IgG3, IgG4) specific antisera as revealing reagents. Results: Fourteen of 90 (15.6%) PBC patients had PBC specific ANA reactivity when an anti-IgG (total) antiserum was used as the revealing reagent while 58 (64.4%) were positive when specific antisera to each of the four IgG isotypes were used. The prevailing isotype was IgG3 for MND and IgG1 for RL/M. PBC patients with specific ANA, in particular of the IgG3 isotype, had significantly more severe biochemical and histological disease compared with those who were seronegative. None of the controls was positive. Conclusions: Disease specific ANA are present in the majority of patients with PBC when investigated at the level of immunoglobulin isotype. PBC specific ANA, in particular of the IgG3 isotype, are associated with a more severe disease course, possibly reflecting the peculiar ability of this isotype to engage mediators of damage.

Microbial mimics are major targets of crossreactivity with human pyruvate dehydrogenase in primary biliary cirrhosis

BACKGROUND/AIMS Previous studies on patients with primary biliary cirrhosis (PBC) have shown extensive cross-reactivity between the dominant B- and T-cell epitopes of human pyruvate dehydrogenase complex-E2 (PDC-E2), and microbial mimics. Such observations have suggested microbial infection as having a role in the induction of anti-mitochondrial antibodies, through a mechanism of molecular mimicry. However the biological significance of these cross-reactivities is questionable, because PDC-E2 is so highly conserved among various species. METHODS Interrogating protein databases, ten non-PDC-E2 microbial sequences with high degree of similarity to PDC-E2(212-226) were found in Escherichia coli (6), Helicobacter pylori, Pseudomonas aeruginosa, Cytomegalovirus, and Haemophilus influenzae. We report on a study testing reactivity and competitive cross-reactivity against these respective peptides, and in some cases the parent protein, using sera from 55 patients with PBC, compared to reactivity of 190 pathological and 28 healthy controls. RESULTS Cross-reactivity to E. coli mimics was commonly seen in PBC, and in a subset of pathological controls except where there was no evidence of urinary tract infection and correlated with anti-mitochondrial reactivity. CONCLUSIONS E. coli/PDC-E2 cross-reactive immunity characterizes primary biliary cirrhosis; the large number of E. coli immunogenic mimics may account for the dominance of the major PDC-E2 autoepitope.

Primary and secondary liver/kidney microsomal autoantibody response following infection with hepatitis C virus

Liver/kidney microsomal autoantibody type 1 (LKM-1), which characterizes a subtype of autoimmune hepatitis, is also found in some patients with chronic hepatitis C virus (HCV) infection. Whether HCV and LKM-1 are accidentally or causally related is unknown. This case report describes a child who became infected by HCV after liver transplantation for end-stage liver disease caused by alpha 1-antitrypsin deficiency. LKM-1 was detected by immunofluorescence, anti-microsomal reactivity by Western blotting, anti-HCV and anti-GOR by immunoenzymatic assays, and HCV RNA by polymerase chain reaction. Two weeks after HCV infection, immunoglobulin (Ig) M LKM-1 appeared, followed by IgG1 LKM-1, with titers increasing to 1/2560; antibodies to a 50-kilodalton liver microsomal protein appeared 2 months later. Sera from day 1 posttransplant became positive for HCV RNA. HCV RNA was also detected in a liver biopsy specimen obtained 3 months after surgery. The patient did not produce anti-HCV and anti-GOR antibodies throughout the study and had no histological evidence of hepatitis. The temporal relationship between HCV infection and LKM-1 production suggests that HCV may trigger a primary autoimmune response. The lack of liver damage attributable to autoimmunity or viral infection may be caused by immunosuppression.

Antimitochondrial antibodies of immunoglobulin G3 subclass are associated with a more severe disease course in primary biliary cirrhosis

Background/Aims: Primary biliary cirrhosis (PBC) is characterised by the presence of immunoglobulin (Ig) G antimitochondrial antibodies (AMA), which are routinely detected by indirect immunofluorescence (IFL) using composite rodent tissue substrate. The IgG subclass distribution and clinical significance of IFL‐detected AMA in patients with PBC have not been previously studied in detail.

Association between the primary biliary cirrhosis specific anti-sp100 antibodies and recurrent urinary tract infection

BACKGROUND AND AIMS Recurrent urinary tract infections (rUTI) have been suggested to be involved in the induction of anti-mitochondrial antibodies (AMA), the serological hallmark of primary biliary cirrhosis (PBC), in view of the presence of AMA in rUTI women without liver disease and conversely of a high prevalence of rUTI in women with PBC. This prompted us to investigate whether PBC-specific anti-nuclear antibodies (ANA) to sp100, gp210 and lamin B receptor (LBR) antigens may also be related to rUTI. METHODS AND SUBJECTS PBC-specific ANA reactivities were investigated in 20 women with rUTI but without liver disease, some of whom were AMA-seropositive; 40 women with PBC, with or without rUTI; and 104 pathological and 23 healthy controls. RESULTS Among the women with rUTI but without liver disease, 8 (80%) of 10 AMA-positive women reacted with sp100 compared with none of the 10 AMA-negative women. Among the PBC patients, 14 (74%) of 19 with rUTI and 1 (4.8%) of the 21 without rUTI reacted with sp100. None of the rUTI women without liver disease reacted with gp210 or LBR. None of 127 pathological and healthy controls had PBC-specific ANA reactivity. CONCLUSIONS Anti-sp100 reactivity strongly correlates with AMA seropositivity in rUTI women, with or without evidence of primary biliary cirrhosis. These findings provide additional support to the notion that E. coli infection is involved in the induction of PBC-specific autoimmunity. Additional factors must be involved in the progression to overt autoimmune disease.

Diagnostic relevance of anti-filamentous actin antibodies in autoimmune hepatitis

We read with interest the paper by Granito et al 1 reporting on the clinical and diagnostic significance of anti-filamentous actin antibodies (A-FAA) in autoimmune hepatitis type 1 (AIH-1). The authors found that A-FAA, measured by a new commercially available ELISA based on a modified cut-off of 30 instead of the manufacturer’s 20 arbitary units (AU), strictly correlates with the smooth muscle antibody glomerular/tubular (SMA-G/T) pattern,2 also known as the microfilament pattern, mostly seen in patients with AIH-1.1 Their findings further indicate F-actin as the predominant, if not the sole, target of AIH-1-specific SMA reactivity, a notion that has been questioned in the past because of the inconsistent results obtained by several actin-based assays.3,4 We agree with Granito et al 1 …

Neonatal liver disease associated with placental transfer of anti-mitochondrial antibodies.

Background: Anti-mitochondrial antibody is the diagnostic hallmark of primary biliary cirrhosis. Its role in the aetiology of primary biliary cirrhosis is controversial. Methods: Two cases of neonatal hepatitis seropositive for anti-mitochondrial antibody are described. Anti-mitochondrial antibody Ig isotype and epitopic specificity were investigated by immunofluorescence and enzyme immunoassays. Results: In both infants anti-mitochondrial antibody was of the G class, mainly G1 and G3 subclasses, and reacted with two synthetic peptides reproducing major M2 epitopic regions: inner lipoyl domain pyruvate dehydrogenase complex (PDC)-E2162-176 and PDC-E3 binding protein (PDC-E3BP)86-100. One infant also reacted with outer lipoyl domain PDC-E235-49, and 2-oxoglutarate dehydrogenase complex (OGDC)-E299-113. An identical pattern of reactivity was present in their mothers, indicating the maternal origin of the antibodies. Anti-mitochondrial antibody disappeared in the infants with the disappearance of the liver pathology. Conclusions: The simultaneous disappearance of hepatitis and anti-mitochondrial antibody in the infants suggests a possible causal link between the two.

Significance of extractable nuclear antigens in childhood autoimmune liver disease

Antinuclear antibody (ANA) is found in connective tissue disorders and in autoimmune disease. While ANA‐positive connective tissue disorders are subdivided according to possession of specific antibodies to extractable nuclear antigens (ENA) (anti‐ribonucleoprotein (anti‐RNP), anti‐Smith (anti‐Sm), anti‐Ro, anti‐La), little is known about the presence and significance of ENA in autoimmune liver disease. To investigate this, we have tested 35 children with autoimmune hepatitis (AIH) (19 ANA and/or smooth muscle antibody‐positive (ANA/SMA +ve); 16 liver kidney microsomal 1‐positive (LKM‐1 +ve)) and 14 with ANA/SMA +ve autoimmune sclerosing cholangitis (ASC), using both double dimension immunodiffusion and ELISAs. Eighty children with non‐autoimmune liver disease (20α1‐antitrypsin deficiency, 20 Wilsons disease. 20 Alagilles syndrome and 20 chronic hepatitis B virus infection) and 20 healthy controls were also tested. ENA were detected in seven (20%) patients with AIH: two ANA‐positive, one SMA‐positive and four LKM‐1‐positive. Three were positive for anti‐Sm, two for anti‐La, one for anti‐Sm/anti‐La and one for anti‐Sm/anti‐La/anti‐Ro. ENA‐positive had more severe liver disease than ENA‐negative patients (P < 0·03). ENA were not detected in ASC, non‐autoimmune liver diseases and controls. Our results indicate that ENA reactivity, including anti‐Sm and anti‐La, characteristic of systemic lupus erythematosus and Sjögrens syndrome, respectively, are present in some patients with AIH even in the absence of ANA, and may characterize a particularly severe form of the disease.