Increased intestinal clearance of alpha 1-antitrypsin in patients with alpha 1-antitrypsin deficiency

To evaluate the possible contribution of enteric losses of alpha 1-antitrypsin (alpha 1-AT) to the low serum levels of alpha 1-AT seen in patients with alpha 1-AT deficiency, we investigated intestinal clearance of alpha 1-AT (C-alpha 1-AT) in five of these patients (mean age 3.4 years) and compared it to that of 10 patients (mean age 3.7 years) with gastrointestinal disorders and normal serum albumin values who served as controls. C-alpha 1-AT was also determined in four patients (mean age 9 months) with noncirrhotic liver disease. The percent of daily alpha 1-AT turnover which could be attributed to stool losses was calculated in these groups of patients. alpha 1-AT was measured in stool and serum by radial immunodiffusion and the clearance calculated. The mean C-alpha 1-AT in the patients with alpha 1-AT deficiency was significantly (p less than 0.05) higher than that of the controls. The liver disease patients had values for C-alpha 1-AT in the range of the controls. Three of the alpha 1-AT deficiency patients had values for C-alpha 1-AT greater than the mean plus 3 SD of the control, but these were not in the range seen in patients with protein losing enteropathy. Mean percent contribution of stool losses to total daily alpha 1-AT turnover was similar in all three groups. We conclude that patients with alpha 1-AT deficiency have increased fecal clearance of alpha 1-AT seemingly unrelated to the liver disease, but that this is not a major cause of the low serum levels.     

儿童α1-抗胰蛋白酶缺乏症1例

<正>患儿,男,5岁,因反复肝功能异常1年半入院。患儿于入托前体检时发现肝功能异常(转氨酶升高),无黄疸及任何不适。曾多家医院检查甲、乙、丙、戊型肝炎病毒血清学标志物均阴性,多次住院护肝降酶治疗,效果不佳。发病以来患儿无明显不适,     

Neonatal gallbladder enlargement and alpha 1-antitrypsin deficiency

Patients with clinical signs of alpha 1-antitrypsin deficiency in the neonatal period usually present with prolonged obstructive jaundice. We report a patient with alpha 1-antitrypsin deficiency who presented with gallbladder enlargement in the neonatal period. This gallbladder enlargement may be due to cystic duct hypoplasia or atresia, which has been reported in association with alpha 1-antitrypsin deficiency. The diagnosis of alpha 1-antitrypsin deficiency should be considered in neonates with gallbladder enlargement and prolonged obstructive jaundice.     

alpha 1-antitrypsin deficiency in early childhood.

Among 200,000 infants screened for alpha 1-antitrypsin (alpha 1-AT) deficiency, 125 Pi Z, 48 Pi Z, 1Pi S-, and 2 Pi Z- children were followed up prospectively. Eleven percent of the Pi Z infants had neonatal cholestasis, and at 2 years of age three of them had cirrhosis. About 50% of the asymptomatic Pi Z and Pi Z- subjects occasionally had serum alanine aminotransferase (ALAT) levels above normal, and in 15% of them the levels were probably permanently increased during the first two years of life. Two previously healthy Pi Z children had transient symptoms of liver disease at age 2 years in connection with severe infections. The Pi SZ children had no significant clinical liver disease and only two had abnormal serum ALAT levels. Among Pi Z children up to 2 years of age the following diseases were also encountered: eight had recurrent bronchitis with wheezing, two had persistant cough (both had cirrhosis), one had severe pneumonia, one was mentally retarded, three had urinary tract infections, six had pronounced eczema, one had allergic shock, and three had congenital malformations. Among the Pi SZ children one had recurrent bronchitis, one had eczema, and one had juvenile rheumatoid arthritis. Three children, two Pi Z and one Pi SZ, have died. The Pi Z- and Pi S- subjects were healthy. In conclusion a variety of significant symptoms were observed in about 30% of the Pi Z children compared with 6% of the Pi SZ children during the first two years of life.     

Analysis of alpha 1-antitrypsin deficiency using DNA methods

Deficiency of alpha 1-antitrypsin can be diagnosed by DNA methods that are quick and also give reproducible results. Direct DNA analysis of the M, S, and Z alleles of the alpha 1-antitrypsin gene is possible when two molecular biology techniques are combined: a part of the gene is enzymatically replicated according to the pattern of the human DNA that is to be investigated. On hybridization with the various allele-specific pieces of synthetic DNA the copies that have come about in this way give a signal corresponding to the genotype. Only a small amount of material (0.5 microgram DNA) is needed for the investigation. This method is thus suitable for prenatal diagnosis when this is requested by members of a family known to be affected. A total of 53 samples were typed and investigations were carried out in six families.     

Liver in alpha1-antitrypsin deficiency: morphologic observations and in vitro synthesis of alpha1-antitrypsin.

In an effort to characterize the hepatic abnormality in patients with alpha1-antitrypsin deficiency, three unrelated children with the disorder (Pi types ZZ and SZ), two heterozygous parents (Pi type MZ), and three normal subjects (Pi type MM) were studied. As expected, the livers of the ZZ- and SZ-deficient subjects showed abnormal accumulation of alpha1-antitrypsin in the cisternae of the rough endoplasmic reticulum as judged by immunofluorescent and electron microscopic studies. Their parents (MZ phenotype) demonstrated identical although less extensive hepatic abnormalities. Short term cultures of liver tissue in the presence of radiolabeled amino acids showed both synthesis and release of alpha1-antitrypsin in normal control subjects and in the patients with the Z protein. Radiolabeled intracellular alpha1-antitrypsin could not be found. These studies demonstrate synthesis of alpha1-antitrypsin by the livers of normal and genetically deficient subjects in vitro, and suggest several possible mechanisms for alpha1-antitrypsin deficiency.     

Liver transplantation in alpha(1)-antitrypsin deficiency

Only a minority of infants born with alpha(1)-antitrypsin deficiency will develop serious liver disease during childhood, mostly but not always after neonatal cholestasis. Early prognosis is difficult and all children have to be followed up carefully. The liver disease progresses with varying speed and it lacks specific features. At the time of liver transplantation the young patients have no pulmonary disease induced by the deficiency and in those with renal involvement, the kidney problems can mostly be dealt with by conservative therapy. The peri- and postoperative care of the patients who undergo liver transplantation does not differ from the usual routines.     

Hereditary alpha 1-antitrypsin deficiency and infantile cirrhosis of the liver

A report on 9 cases of infantile hepatopathy and cirrhosis of the liver respectively in cases of hereditary autosome-recessive alpha 1-antitrypsin deficiency (alpha 1-ATM). The genetic variants of the serum-protease-inhibitor (Pi) alpha 1-antitrypsin (alpha 1-AT) were examined by means of iso-electric focusing (Polyacrylamidgelen). The gene incidence was of the allel PiZ 0,0138 in the 868 blood donors from the Tyrol and was therefore within the range of the PiZ-frequencies seen in other Central-European populations. The other alleles PiM1, PiM2, PiM3, and PiS, point to the incidence of 0.7062, 0.1480, 0.1037, and 0.0225. The patients under observation (9) are homozygote PiZZ, the clinically healthy parents heterozygote PiZM. Risk of repetition in siblings of the patients is 25%. Early indicative symptoms are prolonged jaundice, acholic stools and hepatomegaly. Further developments are the fading of the hyperbilirubinaemia, temporary improvement in the pathological liver values, a freedom of symptoms for different lengths of time in each case, in the case of two patients, finally, decompensated cirrhosis of the liver and death in hepatic coma. The histological picture of the liver tissue shows PAS-positive storage granula in hepatozytes, intrahepatic hypoplasia of the bile duct, cholestasis as well as early cell necrobiosis, fibrosis and cirrhotic transformation. Course and severity of the liver complaint differ greatly, and are independent of the quantitative alpha 1-antitrypsin deficiency revealed, treatment is purely symptomatic.     

Liver disease associated with alpha1-antitrypsin deficiency in childhood.

Liver disease in children with alpha1-antitrypsin deficiency and protease inhibitor type ZZ does not necessarily carry a bad prognosis. Fourteen of our 18 patients presented with the neonatal hepatitis syndrome and four had hepatomegaly without jaundice. Although four patients have died of cirrhosis and its complications, and three have severe liver disease, most of the 11 others, of whom four are over 13 years of age, have relatively little clinical, biochemical, or histologic evidence of liver disease. Persistent elevation of SGOT during the third year of life and renal or pulmonary problems were associated with a poor prognosis. Liver biopsy early in the course of the disease was not helpful prognostically but was useful in assessment of the severity of liver disease and demonstration of alpha1AT storage, alpha1AT deficiency was found in 29% of our patients who presented with the neonatal hepatitis syndrome. One of seven apparently healthy Pi type ZZ sibs of our patients had significant liver disease which had not been suspected previously.     

Low incidence of alpha 1-antitrypsin deficiency among Filipinos with neonatal cholestatis

AIM: Alpha 1-antitrypsin (AAT) deficiency is the most common genetic cause of liver disease in children. The Pi*S carrier rate among Filipinos is <1%. Its significance in Filipino infants with neonatal cholestasis has not been investigated. The aim of the study was to determine the incidence of AAT deficiency among Filipino infants presenting with neonatal cholestasis. METHODS: Genotype determination that detects Pi*S and Pi*Z alleles was performed using Elucigene AAT reagents (Cellmark Diagnostics, UK). AAT inclusions were identified by light microscopy using periodic acid-Schiff (PAS) stain. RESULTS: Ninety-six infants (mean age: 89 days, 48 males) with a history of jaundice since 2 weeks old and a direct bilirubin level>20% of the total were recruited. Only one patient (1 month old, male) was positive for Pi*S allele and 95 were negative for Pi*S and Pi*Z alleles, with an annual incidence of 0.7%. Of the 96, 49 infants underwent diagnostic percutaneous liver biopsy. All liver biopsy specimen were subjected to PAS stain and two infants, 2 and 4 months old, both with idiopathic neonatal hepatitis, had suspicious findings of AAT globules that was confirmed on immunostain. Both infants were negative for Pi*S alleles. The only patient positive for Pi*S allele was negative for PAS globule on liver biopsy. CONCLUSION: Our results showed a low incidence of AAT deficiency caused by the Pi*S and Pi*Z alleles among Filipino infants presenting with neonatal cholestasis, similar to the low carrier rate in the population.     

Membranoproliferative glomerulonephritis in childhood cirrhosis associated with alpha1-antitrypsin deficiency.

Three alpha1-antitrypsin (alpha1AT) deficient, protease inhibitor type ZZ children who died from cirrhosis and its complications had membranoproliferative glomerulonephritis at postmortem examination. During life, all three had clinical and laboratory evidence of renal disease which became apparent when hepatic decompensation developed. Immunofluorescence studies and electron microscopy performed in one patient revealed subendothelial deposits of alpha1AT, complement, and immune globulins along the glomerular basement membrane. The pathogenesis of these renal lesions is speculative. Glomerular lesions were not observed in kidney sections of 16 children who died from cirrhosis but who were not alpha1AT-deficient. The present study suggests that renal involvement may be yet another manifestation of disease associated with alpha1AT deficiency.     

Neonatal screening for alpha-1-antitrypsin deficiency

The results of a neonatal screening programme for alpha-1-antitrypsin deficiency are presented. Cord blood samples with an alpha-1-antitrypsin concentration below 1.628 mg/ml, as measured by an enzyme-linked immunosorbent assay method, were phenotyped by isoelectric focusing in polyacrylamide gels. Abnormal phenotypes were found in 51% of this group as compared with 11.3% in a control group (P0.0001). Twenty subjects detected by the initial quantitative alpha-1-antitrypsin determination had a highly pathogenic phenotype (PiZZ, PiSS, PiSZ). In the control group only moderately affected individuals were found (PiMS, PiMZ).Abbreviations ELISA emzyme-linked immunosorbent assay - PAGE polyacrylamide gel electrophoresis - HRP horseradish peroxidase