Prognosis of alpha-1-antitrypsin deficiency-related liver disease in the era of paediatric liver transplantation

BACKGROUND/AIM: Alpha-1-antitrypsin deficiency (alpha1ATD) is the commonest metabolic disease leading to liver transplantation (LT) in children. Approximately 10-15% of the PiZZ population develops liver disease. Five percent of them will require LT within the first 4 years of life. This study aimed to investigate the prognosis of the liver disease associated with PiZZ alpha1ATD in the era of liver transplantation and to determine predictors of outcome. METHODS: We reviewed retrospectively the clinical notes of 97 consecutive patients referred from January 1989, when LT became routinely available in our Unit, to July 1998. RESULTS: Of 26 (27%) patients who developed end-stage liver disease, 24 have been transplanted and two are waiting for LT. Twenty-one (81%) of these patients presented with neonatal hepatitis at a median age of 2.1 months. Of 71 (73%) children who have not required LT, 61 (86%) presented with neonatal hepatitis at a median age of 1.6 months. Among infants with neonatal hepatitis who required LT, 18 out of 21 (86%) had jaundice for more than 6 weeks compared with 34 of 61 (56%) who survived without LT (p<0.01). Children requiring LT had higher aspartate aminotransferase (AST) at presentation (p<0.0001) and both higher AST and gamma-glutamyl transferase (GGT) at 6 months (p<0.001), 1-year (p<0.0003) and 5-year (p<0.01) follow up when compared to those who are well without LT. Furthermore, children who developed end-stage liver disease more frequently had severe bile duct reduplication (p<0.01), severe fibrosis (p<0.03) with bridging septa (p<0.02) and established cirrhosis (p<0.04) in the initial liver biopsy. Ninety-five of the 97 children (98%) are currently alive; two died after LT. CONCLUSIONS: The advent of liver transplantation has significantly improved the prognosis of liver disease associated with PiZZ alpha1ATD. Duration of jaundice, severity of histological features and biochemical abnormalities predict outcome at an early stage of the disease.     

Delayed diagnosis of alpha-1-antitrypsin deficiency following post-hepatectomy liver failure: A case report

Post-hepatectomy liver failure(PHLF) is a leading cause of morbidity and mortality following major liver resection. The development of PHLF is dependent on the volume of the remaining liver tissue and hepatocyte function. Without effective pre-operative assessment, patients with undiagnosed liver disease could be at increased risk of PHLF. We report a case of a 60-year-old male patient with PHLF secondary to undiagnosed alpha-1-antitrypsin deficiency(AATD) following major liver resection. He initially presented with acute large bowel obstruction secondary to a colorectal adenocarcinoma, which had metastasized to the liver. There was no significant past medical history apart from mild chronic obstructive pulmonary disease. After colonic surgery and liver directed neo-adjuvant chemotherapy, he underwent a laparoscopic partially extended right hepatectomy and radio-frequency ablation. Post-operatively he developed PHLF. The cause of PHLF remained unknown, prompting reanalysis of the histology, which showed evidence of AATD. He subsequently developed progressive liver dysfunction, portal hypertension, and eventually an extensive parastomal bleed, which led to his death; this was ultimately due to a combination of AATD and chemotherapy. This case highlights that formal testing for AATD in all patients with a known history of chronic obstructive pulmonary disease, heavy smoking, or strong family history could help prevent the development of PHLF in patients undergoing major liver resection.     

Late manifestation of chronic liver disease in adults with alpha-1-antitrypsin deficiency

A review of 19 adult patients with alpha-1-antitrypsin deficiency (A₁AT deficiency) and chronic liver disease revealed a late onset of symptomatic hepatic abnormalities in this condition. Thirteen patients (68%) were 60 years or older when the liver disease was discovered. The mean age of the patients with the ZZ, SZ, and MZ phenotypes was 58, 66, and 72.5 years, respectively; this suggested a later onset of the liver disease in the heterozygotes. At the time of diagnosis, the hepatic condition usually was advanced; in eight patients (42%) the survival was less than two years. The most important associated condition was chronic obstructuve lung disease which was found in 10 patients (53%). We conclude that advanced age and the high incidence of obstructive lung disease make it unlikely that liver transplantation will become a common therapeutic option for adult patients with A₁AT deficiency and associated liver disease. Periodic screening of liver function may be indicated in patients with A₁AT deficiency so that chronic liver disease can be diagnosed early, particularly if current attempts to develop effective medical therapy for this condition are successful.     

The diagnostic value of α1-antitrypsin globules in liver cells as a morphological marker of α1-antitrypsin deficiency

ABSTRACT— In order to determine the diagnostic value of α₁-antitrypsin (AAT) globules as a morphological marker of AAT-deficiency of the Pi-Z type, liver needle biopsies from a prospective series of 600 patients were stained with PAS after pretreatment with diastase and by indirect immunoperoxidase staining for AAT deposits. Serum AAT phenotypes of the patients were determined by means of isoelectric focusing. Thirty-two biopsies were from patients with the Pi-Z allele (31 MZ, 1 Z), and 568 biopsies from patients without the Pi-Z allele. AAT globules larger than 3 μm were found in 16 biopsies of which 15 were from patients with the Pi-Z allele (diagnostic specificity 0.94), whereas 20 of 26 biopsies with AAT globules larger than 1 μm were from Pi-Z patients (diagnostic specificity 0.77). Only 47% of the biopsies from patients with the Pi-Z allele contained AAT globules larger than 3 μm. Thus, although AAT globules larger than 3 μm are highly specific as a morphological marker of the Pi-Z allele, their rather infrequent occurrence in carriers of the Pi-Z allele indicates that all investigations concerning the correlation between AAT deficiency of the Pi-Z type and liver disease should be based on phenotyping of sera from all the patients.     

The liver in 30-year-old individuals with alpha1-antitrypsin deficiency

Abstract

Objective. Severe (PiZZ) alpha₁-antitrypsin (AAT) deficiency is a risk factor for liver disease, i.e. juvenile cirrhosis in infancy, and cirrhosis and hepatoma in adulthood. Little is known about the risk of liver disease in individuals with moderate (PiSZ) AAT deficiency. To investigate the natural course of AAT deficiency, a cohort of PiZZ and PiSZ individuals identified by the Swedish National neonatal screening programme in 1972–74 is followed regularly. The aim of this study was to compare liver function in this cohort with healthy control subjects aged 30 years. Material and methods. Blood samples were obtained from 89 PiZZ, 40 PiSZ, and 84 control subjects (PiMM), and plasma levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyl (GT) transpeptidase were analysed. Results. The mean values of all liver enzymes were within the normal range in all Pi subgroups. However, the mean AST was higher in the PiZZ and PiSZ subgroups than in the PiMM subgroup (p < 0.001), and the mean ALT was higher in the PiZZ individuals than in the controls (p < 0.05), while GT did not differ significantly among the Pi subgroups. The PiZZ women taking oral contraceptives had higher mean AST and ALT (p < 0.01) and GT (p < 0.05) than the control women taking oral contraceptives. Conclusions. At the age of 30 years, PiZZ and PiSZ individuals have normal plasma levels of the transaminases AST and ALT, although they are significantly higher than those in healthy control subjects. Use of oral contraceptives seems to influence liver enzymes in PiZZ women.     

Alpha-1-antitrypsin and the pathogenesis of emphysema

The review examines the relationship between alpha₁-antitrypsin (α ₁AT) and emphysema. Although other defects occur in subjects with alpha₁-antitrypsin deficiency, it seems likely that a reduction in inhibition due to loss of this inhibitor explains their emphysema. There is a great deal of controversy, however, concerning the role of alpha₁-antitrypsin in subjects without inherited deficiency. There is uncertainty about the presence and function of other elastase inhibitors in the peripheral lung. The function of lungα ₁AT and the presence of elastase activity are dependent upon the techniques used and this probably accounts for different results between research groups. In addition, other relevant factors such as which enzymes cause lung elastolysis, control of neutrophil chemotaxis, and mechanisms of elastin synthesis and repair are less well studied. The overall conclusion is that many aspects of the elastase/antielastase hypothesis of emphysema are poorly understood. Without further information the true role ofα ₁AT will remain largely speculative.     

A novel alpha1-antitrypsin null variant （PiQ0Milano）nt (PiQ0Milano)

Alpha1-antitrypsin deficiency is an autosomal recessive disease characterized by reduced serum levels of alpha1-antitrypsin(AAT)due to mutations in the SERPINA1 gene causing early onset pulmonary emphysema and,occasionally,chronic liver disease.We report an incidental finding of a novel null AAT allele,Q0Milano,consisting of a 17 nucleotides deletion in exon 3 of SERPINA1 gene,in an Italian child with persistently increased liver enzymes,a mild decrease in circulating AAT levels and without any pulmonary disease.Q0Milano variant results in an unfunctional protein lacking of AAT active site,as the resultant protein is truncated near PiS locus involved in AAT protein stability.     

Alpha-1-antitrypsin deficiency in Madeira (Portugal): The highest prevalence in the world

Alpha-1-antitrypsin (AAT) deficiency is a common genetic disease which affects both lung and liver. Early diagnosis can help asymptomatic patients to adjust their lifestyle choices in order to reduce the risk of Chronic Obstructive Pulmonary Disease (COPD). The determination of this genetic deficiency prevalence in Madeira Island (Portugal) population is important to clarify susceptibility and define the relevance of performing genetic tests for AAT on individuals at risk for COPD.Two hundred samples of unrelated individuals from Madeira Island were genotyped for the two most common AAT deficiency alleles, PI*S and PI*Z, using Polymerase Chain Reaction-Mediated Site-Directed Mutagenesis.Our results show one of the highest frequencies for both mutations when compared to any already studied population in the world. In fact, PI*S mutation has the highest prevalence (18%), and PI*Z mutation (2.5%) was the third highest worldwide. The frequency of AAT deficiency genotypes in Madeira (PI*ZZ, PI*SS, and PI*SZ) is estimated to be the highest in the world: 41 per 1000.This high prevalence of AAT deficiency on Madeira Island reveals an increased genetic susceptibility to COPD and suggests a routine genetic testing for individuals at risk.     

Alpha-1 antitrypsin deficiency and the risk of hepatocellular carcinoma in end-stage liver disease

AIM: To evaluate the association between alpha-1 antitrypsin deficiency (A1ATD) and hepatocellular carcinoma (HCC) in patients with end-stage liver disease (ESLD).METHODS: Patients with cirrhosis and ESLD referred to the Cleveland Clinic Foundation for liver transplantation between 2003 and 2014 were included in the study (N = 675). ESLD was defined as having histological features of cirrhosis and/or radiological evidence of cirrhosis in the context of portal hypertension (ascites, variceal bleeding, thrombocytopenia, or hepatic encephalopathy). A1ATD was diagnosed using phenotype characterization (MZ or ZZ), liver biopsy detection of PAS-positive diastase-resistant (PAS+) globules, or both. Patients with other causes of liver diseases such as hepatitis C virus (HCV), alcoholic liver disease and non-alcoholic steatohepatitis (NASH) or NASH were also included in the study. HCC was diagnosed by using imaging modalities, biopsy findings, or explanted liver inspection. Follow-up time was defined as the number of years from the diagnosis of cirrhosis to the diagnosis of hepatocellular carcinoma, or from the diagnosis of cirrhosis to the last follow up visit. The rate of HCC was assessed using time-to-interval analysis for interval censored data.RESULTS: This study included 675 patients. 7% of subjects had A1ATD (n = 47). Out of all subjects who did not have A1ATD, 46% had HCV, 17% had alcoholic liver disease, 19% had NASH and 18% had another primary diagnosis. Of the 47 subjects with A1ATD, 15 had a primary diagnosis of A1ATD (PI*ZZ phenotype and PAS+ globules), 8 had a PI*MZ phenotype alone, 14 had PAS+ alone, and 10 had both the PI*MZ phenotype and PAS+. Median follow-up time was 3.4 (25^th, 75^th percentiles: 1, 5.2) years. The overall rate of hepatocellular carcinoma in all subjects was 29% (n = 199). In the A1ATD group, the incidence rate of HCC was 8.5% compared to 31% in the group of patients with other causes of cirrhosis (P = 0.001). Patients with ESLD due to A1ATD had the lowest yearly cumulative rate of hepatocellular carcinoma at 0.88% per year compared to 2.7% for those with HCV cirrhosis, 1.5% in patients with NASH and 0.9% in alcohol-induced liver disease (P < 0.001).CONCLUSION: Within this group of patients with ESLD, there was no significant association between A1ATD and increased risk of HCC.     

Minimal Liver Disease in Young Persons with Homozygous and Heterozygous Alpha-1-Antitrypsin Deficiency

Of 120 patients who were investigated for moderately elevated liver function tests as the only sign of liver disease, 6 young persons had alpha-l-antitrypsin (AAT) deficiency. Three had a homozygous (Pi ZZ) and three had a heterozygous (Pi MZ) AAT deficiency as measured with isoelectric focusing. An extensive investigation ruled out all other causes of liver disease. The three homozygous patients showed typical periodic acid-Schiff (PAS)-positive globules in their liver biopsies and slight fibrosis, whereas none of the heterozygous patients showed these features. Electron microscopical investigation also showed typical findings in the homozygous but not in the heterozygous patients. Further development of liver disease in these young and apparently healthy AAT-deficient patients with early signs of liver damage is not known. It is possible that these patients will develop severe liver disease later in life. It was possible to detect only the three homozygous patients by histochemical examination of liver tissue, since the heterozygous patients did not show PAS-positive globules in their liver.     

Genetic variants of alpha-1-antitrypsin (AAT)

Abstract: This paper reviews the genetic variants of alpha-1-antitrypsin (AAT) which have been sequenced with special emphasis on the s.c. deficiency variants. These result in AAT low plasma levels via three main mechanisms: 1) intracellular storage; 2) intracellular degradation; 3) lack of synthesis. Intracellular storage occurs with the classical Z variant and with a few variants called M-like, because of their isoelectric focusing (IF) pattern. The storage phenomen causes liver damage and can be demonstrated at both light and electron microscopic level with the help of immuno-histochemistry. We report a new deficiency variant of AAT (M-Cagliari) characterized by very low plasma levels, massive storage of AAT and liver cirrhosis. By using immunohistochemical techniques and DNA analysis we could demonstrate that M-Cagliari has antigenic and genetic properties other than the Z AAT.     

Chronic liver disease in heterozygous α1-antitrypsin deficiency PiZ

Background/Aims: The contribution of the heterozygous state PiZ of α1-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.     

Relation of functional characteristics and serum alpha-1-antitrypsin (AAT) concentration in patients with PiMM phenotype and chronic obstructive pulmonary disease (COPD)

Introduction

The relation of AAT phenotype and COPD still raises lots of controversy. In this study we aimed to investigate relation lung function characteristics, AAT serum level and COPD in smoking and non smoking population.

Patients and methods

This was a prospective non-randomized study in which we evaluated 45 patients with severe (stage IV) COPD. In all patients we determined AAT phenotype, serum AAT levels and lung function tests. We correlated findings in relation to the smoking status.

Results

All patients were MM type homozygotes. Serum AAT concentrations were within the reference values, amounting to 1.66 g/l in smokers and 1.80 g/l in nonsmokers. There was no significant correlation between serum AAT concentrations and lung function parameters. We have observed the higher mean values of ITGV, RV, TLC and RV/TLC in smokers and a statistically significant difference only in ITGV.

Conclusion

All of the investigated patients with severe COPD were MM type homozygotes with normal plasma level of AAT. There was no significant correlation between the phenotype and severity of COPD. We did not find significant relation of plasma AAT level and lung function impairment.