Formation and current results of a patient-organized registry for alpha(1)-antitrypsin deficiency

BACKGROUND: Significant challenges exist to investigating uncommon illnesses because too few patients are seen at any single clinical center to permit appropriate research studies. Recognizing this impediment to clinical research in alpha(1)-antitrypsin deficiency, the Alpha One Foundation, a patient-organized research foundation, has collaborated with clinician-scientists to organize a voluntary registry of individuals with alpha(1)-antitrypsin deficiency. PURPOSE: To facilitate clinical research in alpha(1)-antitrypsin deficiency by organizing a registry of affected individuals willing to be approached to participate in clinical studies. METHODS: Elements of the Alpha One Foundation Research Network Registry include a Medical and Scientific Advisory Committee, composed of physician-investigators and patient advocates, designated clinical resource centers at medical institutions with expertise in the management of individuals with alpha(1)-antitrypsin deficiency, and a data coordinating center with responsibility for database management and analysis. Questionnaires requesting information about demographic features, alpha(1)-antitrypsin phenotype, smoking history, and health-care utilization were distributed to prospective registrants through the following channels: mailings from the Alpha One Foundation; mailings from the clinical resource centers; and distribution by home-care and pharmaceutical companies. Information from this questionnaire formed the basis of the initial registry database. RESULTS: Between May 1997 and June 1999, 7,789 forms were distributed, and forms were returned by 712 unique registrants. Registrants have the following characteristics: mean (+/- SD) age, 49.3+/-13.2 years; women, 47.7%; white, 96.2%; PI*ZZ phenotype, 70.7%; ex-smokers, 73.3%; COPD patients, 87.2% (emphysema patients, 54.2%; chronic bronchitis patients, 33%); and self-reported liver disease, 6.4%. The mean number of physician visits reported by registrants in the preceding 12 months was 7.8+/-9.4, 59% reported currently receiving IV augmentation therapy, and 35% reported using supplemental oxygen at home. Examples of ongoing research studies using this unique database include: (1) a case-control study to evaluate occupational risk factors for obstructive lung disease in individuals with alpha(1)-antitrypsin deficiency and (2) a study to evaluate the health-care costs for affected individuals. CONCLUSIONS: A registry currently including 712 individuals with alpha(1)-antitrypsin deficiency has been organized through a collaboration between physician-investigators and a patient-organized research foundation. Use of the registry has already facilitated studies that were previously difficult because of the paucity of identifiable study subjects. The registry cohort promises to provide an important resource for future clinical and epidemiologic studies.     

alpha1-Antitrypsin augmentation therapy for PI*MZ heterozygotes: a cautionary note

The use of IV augmentation therapy with plasma-derived alpha1-antitrypsin (AAT) has become the standard of care for the treatment of pulmonary disease associated with the severe genetic deficiency of AAT. The Medical and Scientific Advisory Committee of the Alpha-1 Foundation has become aware that physicians are prescribing this expensive blood product for the treatment of individuals with a single abnormal AAT gene, primarily the PI*MZ genotype. We are aware of no evidence that such therapy is effective in this patient population. The most important therapeutic interventions in such patients remain smoking cessation and elimination of other risk factors for lung disease. This commentary discusses the treatment of AAT deficiency and the concerns regarding treatment of PI*MZ individuals. We conclude that clinicians should avoid prescribing augmentation therapy for this heterozygote population.     

Should health-care systems pay for replacement therapy in patients with alpha(1)-antitrypsin deficiency? A critical review and cost-effectiveness analysis

STUDY OBJECTIVES: Assess cost effectiveness for providing alpha(1)-antitrypsin (alpha(1)-AT) replacement therapy to individuals with severe COPD and alpha(1)-AT deficiency. MATERIALS AND METHODS: The electronic databases MEDLINE and EMBASE were searched, and relevant bibliographies were reviewed. Effect size, defined as the absolute risk difference between treated and untreated groups, was taken from the highest level of supporting evidence. The cost for providing alpha(1)-AT replacement therapy was analyzed from a payer perspective and was based on Medicare reimbursement rates. Effect size and costs were varied. The year of life saved was discounted up to 7%. RESULTS: The incremental cost per year of life saved for alpha(1)-AT replacement therapy (60 mg/kg/wk IV) in a 70-kg subject with severe alpha(1)-AT deficiency and an FEV(1) < 50% of predicted based on the National Institutes of Health (NIH) Registry mortality rate data is $13,971. The incremental cost depends substantially on the mortality rate reduction. When the effect size is altered from 10 to 70%, with the cost fixed at $52,000, the incremental cost per year of life saved ranges from $152,941 to $7,330. When effect size is 55% (as in the NIH Registry) but costs are increased almost 300%, from $52,000 to $150,000 per year, then the incremental cost per year of life saved increases from $13,971 to $40,301. CONCLUSION: No randomized, placebo-controlled trials are available to assess mortality rate reduction with alpha(1)-AT replacement therapy. The best currently available data are observational, from the NIH Registry. Based on these data, alpha(1)-AT replacement therapy is cost-effective in individuals who have severe alpha(1)-AT deficiency and severe COPD.     

Cost-effectiveness of population screening for alpha-1 antitrypsin deficiency: a decision analysis

The objective was to assess the cost-effectiveness of population screening for alpha-1 antitrypsin (AAT) deficiency. The design was a Markov-based decision analytic model. Hypothetical cohorts were analyzed from birth and followed over time until death using Monte Carlo simulation. The following strategies were compared: 1) screen all newborns, 2) screen all 10-year-old children, and 3) do not screen. Screenees found to have PI*ZZ AAT deficiency received the benefits of lower smoking rates and were offered augmentation therapy. In keeping with reported experience, most (96%) non-screened AAT deficient individuals remained undiagnosed and, therefore, missed these benefits. Under base conditions, screening all newborns cost nearly $422,000 per quality-adjusted life-year (QALY) gained; this estimate fell to $92,135 per QALY when the cost of screening was minimized to $6 in the model. Delaying screening until age 10 decreased the incremental cost-effectiveness ratio (ICER) to nearly $317,000. In sensitivity analysis, when the prevalence of PI*ZZ individuals increased from a baseline of 1.96 to 16 per 10,000, the ICER for newborn screening decreased below $100,000 per QALY. When the cost of screening and augmentation therapy were decreased simultaneously with increasing PI*ZZ prevalence, there were many scenarios in which the ICER decreased below $50,000. While population-based screening for AAT deficiency is not cost-effective under current conditions, cost-effectiveness criteria could be satisfied when case-finding in a high prevalence population is undertaken.     

Emphysema of early onset associated with a complete deficiency of alpha-1-antitrypsin (null homozygotes)

We have compared lung function in 3 subjects with no alpha 1-antitrypsin (alpha 1-protease inhibitor) (null homozygotes) with subjects having the typical deficiency, PIZZ. We identified a 31-yr-old woman, presenting with severe obstructive lung disease, who had no detectable plasma alpha 1-antitrypsin, indicating homozygosity for a "null" (or PI*QO) allele of alpha 1-antitrypsin. Two of her sisters have a similar deficiency, one with an onset of symptoms at 17 yr of age. Because of the likelihood that there are a number of different PI*QO alleles, the type in this family has been named null Mattawa (QOmattawa). All 3 homozygotes have shown a marked deterioration of lung function over a 7-yr period of follow-up. In contrast, lung function tests of 6 age-matched nonsmoking subjects with alpha 1-antitrypsin deficiency, PI type ZZ, showed no abnormalities of lung function. The 15 to 20% of the normal plasma concentration of alpha 1-antitrypsin associated with the PI*Z allele appears to provide some protection to the lung in comparison with a complete deficiency state.     

Estimated numbers and prevalence of PI*S and PI*Z deficiency alleles of alpha1-antitrypsin deficiency in Asia.

The current study focuses on updating estimates of the numbers of individuals carrying the two most common deficiency alleles, protease inhibitor (PI)*S and PI*Z, for alpha1-antitrypsin deficiency (AT-D) in 20 Asian countries. A total of 170 cohorts with 31,177 individuals were selected from 20 Asian countries. The total AT-D populations in the countries selected were: 7,264 ZZ; 36,754 SZ; 6,672,479 MZ; 46,492 SS; and 16,881,108 MS. Marked differences among the Asian countries and regions were also found for the prevalence of the deficiency alleles PI*S and PI*Z. These numbers demonstrate that AT-D is not just a genetic disease that affects smaller numbers than various countries, for example, in Europe. There were marked differences between the prevalence of the PI*S and PI*Z deficiency alleles among these 20 Asian countries as well as among the countries within a given geographic region in Asia. The largest numbers of ZZ phenotypes (3,000-14,000) were in Afghanistan, Pakistan, Saudi Arabia and Thailand; with <1,700 in each of the remaining countries.     

Longitudinal follow-up of patients with alpha(1)-protease inhibitor deficiency before and during therapy with IV alpha(1)-protease inhibitor

BACKGROUND: The efficacy of IV augmentation therapy with human alpha(1)-protease inhibitor (alpha(1)-Pi) in patients with severe alpha(1)-Pi deficiency is still under debate. STUDY OBJECTIVES: To evaluate the progression of emphysema in patients with alpha(1)-Pi deficiency before and during a period in which they received treatment with alpha(1)-Pi. DESIGN: Multicenter, retrospective cohort study. SETTING: Outpatient clinics of 26 university clinics and pulmonary hospitals. PATIENTS: Ninety-six patients with severe alpha(1)-Pi deficiency receiving weekly augmentation therapy with human alpha(1)-Pi, 60 mg/kg of body weight, had a minimum of two lung function measurements before and two lung function measurements after augmentation therapy was started. Lung function data were followed up for a minimum of 12 months both before and during treatment (mean, 47.5 months and 50.2 months, respectively). MEASUREMENTS AND RESULTS: Patients were grouped according to the severity of their lung function impairment. The change in FEV(1) was compared during nontreatment and treatment periods. In the whole group, the decline in FEV(1) was significantly lower during the treatment period (49.2 mL/yr vs 34.2 mL/yr, p = 0.019). In patients with FEV(1) > 65%, IV alpha(1)-Pi treatment reduced the decline in FEV(1) by 73.6 mL/yr (p = 0.045). Seven individuals had a rapid decline of FEV(1) before treatment, and the loss in FEV(1) could be reduced from 256 mL/yr to 53 mL/yr (p = 0.001). CONCLUSION: Some patients with severe alpha(1)-Pi deficiency and well-preserved lung function show a rapid decline in FEV(1). These patients profit from weekly IV therapy with human alpha(1)-Pi and have less rapid decline if treated. Early detection of patients at risk and early start of augmentation therapy may prevent accelerated loss of lung tissue.     

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.     

The protease inhibitor PI*S allele and COPD: a meta-analysis.

In many countries, the protease inhibitor (SERPINA1) PI*S allele is more common than PI*Z, the allele responsible for most cases of chronic obstructive pulmonary disease (COPD) due to severe alpha 1-antitrypsin deficiency. However, the risk of COPD due to the PI*S allele is not clear. The current authors located studies that addressed the risk of COPD or measured lung function in individuals with the PI SZ, PI MS and PI SS genotypes. A separate meta-analysis for each genotype was performed. Aggregating data from six studies, the odds ratio (OR) for COPD in PI SZ compound heterozygotes compared with PI MM (normal) individuals was significantly increased at 3.26 (95% confidence intervals (CI): 1.24-8.57). In 17 cross-sectional and case-control studies, the OR for COPD in PI MS heterozygotes was 1.19 (95%CI: 1.02-1.38). However, PI MS genotype was not associated with COPD risk after correcting for smoking. Furthermore, mean forced expiratory volume in one second, a measure of airflow obstruction and a defining feature of COPD, did not differ between PI MS and PI MM individuals. There were not enough cases to summarise the risk of COPD in PI SS homozygotes. In conclusion, the results show that the PI SZ genotype is a significant risk factor for chronic obstructive pulmonary disease. The risk of chronic obstructive pulmonary disease due to the PI MS genotype is not substantially elevated.     

Rare alpha-1-antitrypsin variants: are they really so rare?

Alpha-1-antitrypsin (α1-AT) deficiency is mainly evaluated in the diagnostic process of chronic obstructive pulmonary disease (COPD). Around 95% of individuals with severe α1-AT deficiency carry the PI*ZZ genotype. Little is known about the epidemiology of the remaining deficient α1-AT variants, which are called 'rare' due to their low prevalence. The retrospective revision of 3511 α1-AT deficiency determinations performed in Barcelona from 1998 to 2010 detected 1.6% of cases with rare α1-AT alleles, a rate similar to those reported in other European studies. Among these variants, PI*I and PI*Mmalton represented 54% of cases. Hence, the so-called 'rare' α1-AT alleles may not be rare as has been assumed. It would be of interest to implement simple allele-specific molecular biology methods to study the most prevalent rare variants in each region. Augmentation therapy is recommended in patients with emphysema and PI*ZZ genotype, but there is little evidence regarding the implications of rare variants on therapy.     

The prevalence of alpha(1)-antitrypsin deficiency in a representative population sample from Poland

AIM: Severe alpha(1)-antitrypsin (AAT) deficiency is one of the most common genetic disorders in Caucasians. The aim of the present study was to assess an unbiased frequencies of PI*S and PI*Z alleles using genotyping of a representative sample from the general population of Poland. METHODS: A random sample of age- and gender-stratified residents, aged 20 years or older, was drawn from the municipal directory of Kraków, Poland. The two most common deficiency alleles: PI*S and PI*Z were genotyped with qualitative real-time PCR using degenerative dual-labeled allele-specific fluorescent probes. RESULTS: In the total population of 859 adult subjects (mean age: 49.5 years; range: 20-90), 28 heterozygotes MS, 18 heterozygotes MZ and one homozygote S were diagnosed. The frequency of PI*S allele was 17.5 (95% CI: 11.6-23.9) per 1000; and that of PI*Z was 10.5 (95% CI: 5.8-15.7) per 1000. Therefore, the estimated prevalence of inherited severe AAT deficiency (homozygotes Z) in Poland is 1/9110 (95% CI: 1/4057-1/29,727). CONCLUSIONS: In the whole population of Poland comprising 38 millions, one may expect of about 4189 (95% CI: 1284-9406) subjects with severe AAT deficiency. These numbers are high enough to consider genetic testing being introduced into a common clinical practice.     

Genomic DNA extraction from small amounts of serum to be used for alpha1-antitrypsin genotype analysis.

If laboratory diagnosis of alpha1-antitrypsin (alpha1-AT) deficiency is usually based on its phenotype identification by isoelectric focusing, alpha1-antiprotease inhibitor (Pi)S and PiZ genotypes can also be determined by deoxyribonucleic acid (DNA)-based methods. Recently, several methods have been described for preparing genomic DNA from serum. The aim of the current study was to determine the Pi allele from serum extracted DNA by polymerase chain reaction (PCR) and to compare these results with those obtained with whole blood extracted DNA. Serum alpha1-AT concentration and phenotypic identification were systematically performed in 43 hospitalised patients. Genomic DNA was simultaneously purified from whole blood and from serum. The mutation detection was found using a PCR-mediated site-directed mutagenesis method. Concerning phenotypic identification, 29 patients were MM homozygotes, 11 were heterozygotes for S (MS = 7) or for Z (MZ = 4) and three showed a ZZ phenotype. Genotyping analyses gave identical results with serum and whole blood extracted DNA and all the results were in agreement with the phenotyping results. The authors found that the deoxyribonucleic acid-based test proved to be a reliable tool for alpha1-antitrypsin deficiency diagnosis and appears to be an alternative for the labour intensive alpha1-antitrypsin determination by isoelectric focusing. The authors also concluded that this method yields good quality deoxyribonucleic acid from serum, equal to that extracted from whole blood and is helpful in retrospective studies of multiple genetic markers.     

Estimated numbers and prevalence of PI*S and PI*Z alleles of alpha1-antitrypsin deficiency in European countries.

The current study focuses on developing estimates of the numbers of individuals carrying the two most common deficiency alleles, PI*S and PI*Z, for alpha1-antitrypsin deficiency (AT-D) in Europe. Criteria for selection of epidemiological studies were: 1) AT phenotyping performed by isoelectrofocusing or antigen-antibody crossed electrophoresis; 2) rejection of "screening studies"; 3) statistical precision factor score of > or = 5 for Southwest, Western and Northern Europe, > or = 4 for Central Europe, > or = 3 for Eastern Europe; and 4) samples representative of the general population. A total of 75,390 individuals were selected from 21 European countries (one each from Austria, Belgium, Latvia, Hungary, Serbia-Montenegro, Sweden and Switzerland; two each from Denmark, Estonia and Lithuania; three each from Portugal and the UK; four each from Finland, The Netherlands, Norway and Spain; five each from Russia and Germany; six from Poland; eight from Italy; and nine from France). The total AT-D populations of a particular phenotype in the countries selected were: 124,594 ZZ; 560,515 SZ; 16,323,226 MZ; 630,401 SS; and 36,716,819 MS. The largest number of ZZ (5,000-15,000) were in Italy, Spain, Germany, France, the UK, Latvia, Sweden and Denmark, followed by Belgium, Portugal, Serbia-Montenegro, Russia, The Netherlands, Norway and Austria (1,000-2,000), with < 1,000 in each of the remaining countries. A remarkable lack in number of reliable epidemiological studies and marked differences among these European countries and regions within a given country was also found.     

Italian Registry of Patients with Alpha-1 Antitrypsin Deficiency: General Data and Quality of Life Evaluation

Abstract

Alpha1-antitrypsin Deficiency (AATD) is a rare hereditary disorder with an estimated prevalence of about 1/5000 individuals in Italy. Deficient patients are at a higher risk of developing lung emphysema and chronic liver disease. The low estimated prevalence of AATD prompted the establishment of a registry with the aim of learning more about the natural history and the quality of care of these patients. The Italian registry for AATD was established in 1996. In this study, genetic and clinical findings of Italian AATD patients are presented. Moreover, we also evaluated the changes in health-related quality of life (HRQoL) in patients with COPD and AAT deficiency over a three-year period, in relation to augmentation therapy.

In a period spanning 18 years (1996–2014) a total of 422 adult subjects with severe AATD were enrolled, namely 258 PI*ZZ, 74 PI*SZ, 4 PI*SS and 86 patients with at least one rare deficient allele. The 21.3% frequency for AATD patients with at least one deficient rare variant is the highest so far recorded in national registries of AATD. The registry data allow a detailed characterization of the natural course of the disease and the level of patient care, as well as confirm the usefulness of early AATD detection.     

Study of alpha1-antitrypsin phenotypes frequencies in patients with primary antibody deficiency

Primary antibody deficiencies are the most frequent primary immunodeficiency disorders. Bronchiectasis as a feature of these disorders may be developed due to some factors such alpha-1- antitrypsin deficiency. In order to determine the prevalence of two common alpha-1-antitrypsin deficiency alleles (PI*Z and PI*S) in Iranian patients with antibody deficiency, this study was performed. The prevalence of PI*M, PI*S, and PI*Z allele combinations was determined in 40 patients with primary antibody deficiency (with and without bronchiectasis) and compared with 60 healthy control subjects. Phenotyping was performed by isoelectric focusing. The phenotype frequencies among patients were as follow: M in 92.5%, S in 2.5% and Z in 5%. There was not any significant difference in distribution of alleles or phenotypes between patients and control subjects. Moreover, no significant difference was found between patients with and without bronchiectasis. We did not find evidence to support an association between alpha-1-antitrypsin phenotypes and primary antibody deficiencies in a small, controlled study. Larger studies will be required to clarify the relationship between alpha-1-antitrypsin genotype and susceptibility to bronchiectasis in patients with antibody deficiency.     

Augmentation therapy reduces frequency of lung infections in antitrypsin deficiency: a new hypothesis with supporting data

STUDY OBJECTIVES: To propose an hypothesis that antiprotease augmentation therapy reduces the incidence of lung infections in alpha(1)-antitrypsin (AAT)-deficient patients, and to present supporting data. DESIGN: The proposed concept is based on a survey taken via the Internet of patients receiving augmentation therapy for 1 to 10 years compared to similar patients not receiving such therapy. SETTING: A questionnaire was submitted to patients with a ZZ phenotype for AAT deficiency to determine whether those receiving antitrypsin augmentation therapy were aware of any personal benefit, and whether the therapy had an effect on the frequency of lung infections. PATIENTS: Ninety-six adult patients receiving human alpha(1)-proteinase inhibitor (alpha(1)-PI) responded, as did 47 similar patients not receiving augmentation therapy. RESULTS: Seventy-four of 89 patients who had received alpha(1)-PI infusions for > 1 year believed that they had definitely benefited from such therapy. Fifty-six of the 74 patients claiming a benefit attributed this to a reduction in the number of lung infections since starting therapy with alpha(1)-PI infusions. Before starting alpha(1)-PI, the majority of patients had three to five infections per year, dropping to zero to one infection per year during alpha(1)-PI therapy (p < 0. 001). CONCLUSIONS: Replacement therapy for AAT deficiency-associated emphysema appears to be associated with a marked reduction in the frequency and severity of lung infections. This association must be evaluated further in future, more rigid, prospective studies of AAT augmentation therapy. Findings support the hypothesis that antiprotease therapy with alpha(1)-PI reduces the incidence of lung infections in addition to slowing the deterioration of lung function and causing a reduction in mortality.     

Anti-neutrophil-elastase defenses of the lower respiratory tract in alpha 1-antitrypsin deficiency directly augmented with an aerosol of alpha 1-antitrypsin

STUDY OBJECTIVE: To determine if aerosolization of purified human plasma alpha 1-antitrypsin is an effective means for increasing lower respiratory anti-neutrophil-elastase defenses in alpha 1-antitrypsin deficiency. DESIGN: Nonrandomized, before-and-after trial with a 7-day treatment period. Companion studies in animals to determine lung epithelial permeability to alpha 1-antitrypsin. PATIENTS: Twelve patients with homozygous Z-type alpha 1-antitrypsin deficiency and mild to moderate emphysema. INTERVENTIONS: Aerosol administration of human plasma alpha 1-antitrypsin, 100 mg every 12 hours for 7 days. Single, 100-mg aerosol dose to anesthetized sheep with indwelling thoracic lymph duct catheters for direct assessment of lung permeability. MEASUREMENTS AND MAIN RESULTS: Treatment resulted in increased alpha 1-antitrypsin levels in the lung epithelial lining fluid (0.28 +/- 0.07 microM before therapy to 5.86 +/- 1.03 microM after therapy) and increased anti-neutrophil-elastase capacity (0.78 +/- 0.38 microM before therapy to 4.16 +/- 0.95 microM after therapy). Aerosolized alpha 1-antitrypsin diffused across the respiratory epithelium and entered lung interstitial lymph (in sheep) and reached the systemic circulation (in sheep and humans). No side effects were noted. CONCLUSION: Short-term aerosol administration of human plasma alpha 1-antitrypsin to patients with alpha 1-antitrypsin deficiency is safe and feasible, resulting in a return to normal of anti-neutrophil-elastase defenses in the lower respiratory tract. The aerosol approach, therefore, merits serious long-term evaluation as an alternative to other parenteral forms of administering therapeutic proteins.     

The flaccid lung syndrome and alpha 1-protease inhibitor deficiency

We examined breathing mechanics and alpha 1PI deficiency in 1,850 unrelated male subjects with various lung complaints. The loss in lung elasticity appeared to be significantly more pronounced in ZZ individuals as compared to MM, MS and also MZ individuals. The MZ group did not differ significantly in this respect from MM individuals. This implies that the excess risk of developing a flaccid lung (C greater than 1 kPa-1) due to the partial alpha 1-antitrypsin deficiency is negligible. PI MZ and PI ZZ frequencies are significantly higher in the population with flaccid lung compared to control subjects. Furthermore, it was found that the increase in residual volume in smokers is independent of the PI type.     

Alpha1-antitrypsin genotypes in patients with chronic pancreatitis

BACKGROUND: An association between alpha1-antitrypsin deficiency and chronic pancreatitis (CP) has been reported in several case reports and two systematic studies. However, conflicting results have been shown in other studies of patients with CP. All previous studies were performed by phenotyping or by measurement of serum concentrations of alpha1-antitrypsin. The aim of this study was to investigate the relationship between alpha1-antitrypsin deficiency and CP by genetic analysis. METHODS: Ninety-six unrelated children and adolescents with idiopathic or hereditary CP and 185 healthy controls were enrolled. DNA was extracted from peripheral blood leukocytes and the exons 5 and 7 of the alpha1-antitrypsin gene were amplified by polymerase chain reaction using mutagenic forward primers introducing a Taq I restriction site. Genotyping of the S allele and the Z allele was performed by restriction fragment length polymorphism analysis using Taq I. RESULTS: Seven out of 96 patients (7.3%) with CP were heterozygous for an alpha1-antitrypsin deficiency allele (4 for the S allele and 3 for the Z allele). No patient was homozygous or compound heterozygous for these alleles. Twenty out of 185 control individuals (10.8%) were heterozygous for the S or Z allele (PiS: 12 controls; PiZ: 8 controls). No significant differences were found between the allele frequency in patients and the control individuals (P > 0.1). CONCLUSIONS: Alpha1-antitrypsin deficiency is not related to the pathogenesis of idiopathic or hereditary CP.