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Inherited defects of the gene coding for a serum protein that protects alveolar walls from proteolysis constitute one cause of emphysema, with or without liver disease. The deficiency can be reversed with intravenous administration of the antiprotease, keeping serum levels above the minimum needed for lung protection.
It is well known that incidence of chronic obstructive lung disease in adult patients with alpha 1-antitrypsin deficiency (ATD) is high. Adult carriers of this genetic trait with cirrhosis of the liver, and also with fibrosis of the liver and hepatoma, have been reported. A causal relationship between ATD and liver lesions has been suspected. In most cases liver disease has been recognized at post morten, - in a few cases, however, intra vitam, when severe symptoms of the liver disease had become apparent. The case of a 59 year-old patient is reported with PIZZ-homozygous ATD, moderate pulmonary emphysema and with marked portal fibrosis and focal transition in cirrhosis of the liver without any sequelae. The clinical course has been rather benign so far.
The five siblings of a family with alpha 1-antitrypsin deficiency including three of Pi- and two of PiM- phenotypes, were studied for the development of pulmonary emphysema during nine years. The changes of pulmonary function showed significant decrease in FEV1.0 and V50, and increase in RV/TLC. Clinical diagnoses for each patient were assessed by pulmonary function, inhalation and perfusion lung scintigram. Two case of Pi- phenotypes were diagnosed definite pulmonary emphysema 9 years previously, in one case of Pi- emphysema was suspected and two PiM- cases were also suspected of emphysema. alpha 1-antitrypsin and elastase inhibitory capacity (EIC) were investigated in serum and bronchoalveolar lavage fluids (BALF) from four patients with alpha 1-antitrypsin deficiency, healthy non-smokers and smokers. alpha 1-Antitrypsin and EIC in BALF in patients with alpha 1-antitrypsin deficiency were markedly decreased. There were no differences between non-smokers and smokers in alpha 1-antitrypsin and EIC, but EIC in BALF showed a significant correlation with DLCO or %DLCO. These findings suggest that a deficiency of alpha 1-antitrypsin results in insufficient antielastase protection in the lower respiratory tract, and EIC in BALF may be useful for detecting early changes of emphysema.
BACKGROUND: Alpha-1-antitrypsin is the body's major inhibitor of human neutrophil elastase, a powerful proteolytic enzyme capable of degrading the common tissue components. There are over 70 genetic variants of alpha-1-antitrypsin, with the Z allele being of greatest clinical relevance. Individuals homozygous for this allele (approximately one in 2500 in Caucasians) have low serum alpha-1-antitrypsin levels (10-20% of normal) and are predisposed to emphysema, especially if they smoke. Much rarer are mutations which result in the complete or almost complete absence of alpha-1-antitrypsin in the serum. AIM: To determine the cause of complete absence of alpha-1-antitrypsin in a patient who at age 27 years had both emphysema and idiopathic cardiomyopathy. METHODS: Molecular biology techniques were used to sequence the alpha-1-antitrypsin gene. Allele specific amplification was used to show the presence of the mutations in other family members. RESULTS: Investigation showed that the proband was homozygous for the Pi Null Bellingham variant of alpha-1-antitrypsin due to the mutation Lys 217 (AAG) to Stop (TAG). His grandmother was heterozygous for Pi Null Bellingham and the additional rare variant P Lowell, Asp 256 (GAT) to Val (GTT), a variant that also results in alpha-1-antitrypsin deficiency. CONCLUSION: Patients with complete absence of alpha-1-antitrypsin develop premature emphysema not having smoked or after only minimal exposure, and much earlier than the more common Pi Z individuals who have the usual form of alpha-1-antitrypsin deficiency.
We report three elderly patients who presented with increasing dyspnoea on exertion and radiological evidence of basal bullous emphysema. On further investigation they were found to have alpha-1-antitrypsin deficiency. We emphasize that alpha-1-antitrypsin deficiency can present much later than is usually the case especially if the patient is a life-long non-smoker.
We examined the role of intermediate alpha 1-antitrypsin deficiency in predisposing to abnormalities of lung distensibility and airway function in 20 heterozygotes (Pi MZ) who were individually matched with a control Pi M subject of similar age, height, and smoking habits drawn from the same male, working population. There were no significant differences between the heterozygotes and their controls in the results of spirometry, maximum expiratory flow-volume curves (breathing air), single breath nitrogen test, arterialised capillary blood oxygen pressure, or single breath carbon monoxide transfer. Additional studies were made in 12 of the pairs of Pi MZ and Pi M subjects. Comparison of maximum expiratory flow-volume curves breathing air and 80% helium-20% oxygen showed no differences between the Pi MZ and Pi M subjects. Although airway function was similar in the two groups, four of 12 Pi MZ subjects showed abnormalities of the pressure-volume curve of the lung (reduction in lung recoil pressure, abnormal shape factor, increase in functional residual capacity). Abnormalities of washout of a helium-sulphur hexafluoride gas mixture, of a type previously described as characteristic of emphysema, were found in two of the men with abnormal pressure-volume curves. The results suggest that Pi MZ subjects have an increased susceptibility to alveolar abnormalities without increased abnormalities of airway function; this may explain the increased frequency of emphysema at necropsy despite many studies showing no predisposition to abnormal airway function in life. The functional changes we observed would be unlikely to cause symptoms. The risk of disablement from chronic lung disease appears to be only slightly enhanced by intermediate alpha 1-antitrypsin deficiency.
alpha 1-Antitrypsin (AAT) is a polymorphic protein with many variants collectively known as the Pi system. The most common alleles are the M, S and Z, which are co-dominantly inherited. Infants with PiZZ have approximately 16% of the normal AAT serum concentration. alpha 1-Antitrypsin deficiency (AATD) is an inborn error of metabolism which is principally associated with liver disease in children and emphysema in young adulthood. Individuals with AATD produce an abnormal protein which accumulates in the liver, resulting in decreased serum levels. Affected individuals cannot protect their lungs from digestion by elastase. Smoking is a significant risk factor for the early development of emphysema. Prolastin, human alpha 1-protease inhibitor, is now available as replacement therapy. Weekly intravenous administration, with the goal of maintaining the serum AAT greater than 80 mg/dl, appears to arrest pulmonary damage. Its effect on liver disease is unknown at this time. A recombinant alpha 1-protease inhibitor is being tested in aerosol form with promising early results.
BACKGROUND: For individuals with emphysema because of severe alpha(1)-antitrypsin deficiency, specific therapy called IV augmentation therapy has been available since 1989. Such therapy consists of IV infusion of pooled human plasma alpha(1)-antiprotease. METHODS: To assess the direct medical costs of having alpha(1)-antitrypsin deficiency, the current study surveyed members of the Alpha One Foundation Registry for Individuals With alpha(1)-Antitrypsin Deficiency regarding their annual expenditures for treatment of this disease. Data regarding demographic features, alpha(1)-antitrypsin status, and health-resource utilization were collected from a self-administered questionnaire. Respondents were asked to provide total health-care expenditures, but costs by specific items of care (eg, drugs, physician visits, etc) were not available. RESULTS: Mean annual cost estimates were higher for PI*ZZ-phenotype individuals ($30,948, n = 292) than for non-PI*ZZ-phenotype individuals ($20,673, n = 53; p = 0.049). Among PI*ZZ-phenotype individuals, self-reported costs of health-care services were further analyzed for those 288 individuals whose alpha(1)-antiprotease use status was reported. For the 185 current alpha(1)-antiprotease users, the mean annual cost was $40,123 (median, $36,000). CONCLUSIONS: Annual health-care expenditures by individuals with alpha(1)-antitrypsin deficiency are very high, whether or not they are currently receiving augmentation therapy. Augmentation therapy adds substantial costs, especially for heavier individuals who are receiving weekly infusions.
The dysbalance between proteolytic neutrophil elastase and its endogeneous inhibitor seems to be a pathogenetic key mechanism in the origin of pulmonary emphysema (elastase-antielastase hypothesis). This hypothesis is supported by the observation, that low serum levels of alpha 1-antitrypsin can be observed in smokers with premature pulmonary emphysema. alpha 1-proteinase inhibitor is an acute phase protein with known structural and moleculargenetic aspects, which is synthesized by the liver and reaches the lung by the circulation. Its role is the inactivation of excessive neutrophil elastase in the pulmonary parenchyma, which is liberated during inflammation and destroys elastin and other components of extra-cellular connective tissue matrix. This is an overview on epidemiology, clinical aspects, genetics and molecular biology of this particular disease which was described in 1963.
DEFINITION: Alpha-1 antitrypsin (alpha-1 proteinase inhibitor) deficiency is characterized by a marked reduction of alpha-1 antitrypsin, the major antiprotease in man. PREVALENCE: Alpha-1 antitrypsin deficiency is one of the most common hereditary diseases in Caucasians of European descent. Alpha-1 antitrypsin deficiency is the underlying disorder in approximately 2% of all patients with chronic obstructive pulmonary disease and lung emphysema. CLINICAL MANIFESTATIONS: Young adults by the age of 30 to 45 years have a high risk for the development of lung emphysema with cough, sputum expectoration and respiratory insufficiency. There is a moderate risk of liver disease. DIAGNOSTIC PROCEDURES AND TREATMENT: The diagnosis is obtained by measurement of alpha-1 antitrypsin serum levels. Recognition of the disorder is important to prevent deterioration of the pulmonary function by early initiation of preventive measures and treatment. Therapeutic options are physiotherapy, antiobstructive medication and antibiotics. The most direct approach is the intravenous augmentation therapy with purified alpha-1 antitrypsin.
An association of alpha 1-antitrypsin deficiency with glomerulonephritis is rare and has so far been observed only in children or young adults. We report a 63-year-old man with severe alpha 1-antitrypsin deficiency associated with pulmonary emphysema, cirrhosis of the liver, and mesangioproliferative glomerulonephritis with nephrotic syndrome. Following initial presentation with nephropathy, further work-up revealed alpha 1-antitrypsin deficiency of proteinase inhibitor Z. In the absence of glomerular alpha 1-antitrypsin deposits the relationship between renal disease and alpha 1-antitrypsin deficiency remains unclear. alpha 1-Antitrypsin deficiency should be considered in adults with abnormal renal function and chronic liver disease.
alpha 1-Antitrypsin inhibits various proteases and excessive proteolysis. If serum and tissue concentrations of this compound are low throughout longer periods of time due to deficient synthesis, - which is a dominantly inherited trait, - progressive pulmonary emphysema will develop in adults, and liver disease in more than 50% of the cases in infancy and early childhood. Three subtypes can be distinguished: the heaptitis type, the intrahepatic hypoplasia of the bile duct system, and the cholangitic type which may imitate atresia of bile ducts. Prognosis of the liver disease depends upon the time, at which inflammatory processes stop, excessive proteolysis coming to a stop at the same time. No treatment is known for this disease.
A patient with pulmonary emphysema is described, who had a very low alpha 1-antitrypsin serum concentration (2% of normal). After isoelectric focusing and staining, the patient's serum revealed no visible alpha 1-antitrypsin bands. Immunofixation, following isoelectric focusing, gave a banding pattern identical to that of a normal M type. The existence of this deficient M-allele was confirmed by family studies. Low alpha 1-antitrypsin concentrations, due to the presence of the deficient allele, were coupled with low serum antitrypsin activities.
RATIONALE AND OBJECTIVES: To determine and analyze the most important error sources in lung CT densitometry in vivo. METHODS: The authors examined the influences of CT acquisition errors, physiologic changes, and image segmentation errors on lung densitometry. Among others, spatial dependency and long-term reproducibility of the density measurements of blood and air were examined over a period of 4 years in a group of 28 patients with pulmonary emphysema. These results were related to the measured lung densities in this group. RESULTS: The density measurement of blood and air is strongly dependent on the position in the thorax. Despite full-scanner calibrations, x-ray tube replacement can induce a significant increase in measured blood density. CONCLUSIONS: A change in a lung density parameter over time can actually be the result of tube replacement or changing blood density. A simple postprocessing technique can correct for these changes.
alpha 1-Proteinase inhibitor (alpha 1-PI) augmentation therapy has been licensed for treatment of alpha 1-PI-deficient individuals with pulmonary emphysema. The currently available product is purified from pooled human plasma. To obtain larger amounts of protein free from possible unknown plasma contaminants, human alpha 1-PI has been produced by recombinant DNA. Since wild-type alpha 1-PI is susceptible to oxidative impairment, several alpha 1-PI variants in which the active site oxidation-sensitive residue is replaced by inert residues have been constructed. This article is aimed at reviewing the history, biological efficacy, advantages, disadvantages, and concerns linked to alpha 1-PI recombinant DNA and site-specific mutagenesis technology.
Clinical data from 246 adult Swedish individuals with severe alpha1-antitrypsin deficiency, Pi Z, diagnosed in 1963--77, were analyzed. Primary emphysema was present in 109 cases. Of 75 Pi Z patients with other types of chronic obstructive pulmonary disease (COPD), all but 7 showed signs of emphysema. Median age at onset of dyspnoea in Pi Z smokers was 40 years, compared to 53 in non-smokers (p less than 0.001). Of the Pi Z individuals over the age of 50, 19% had a diagnosis of liver cirrhosis and 15% signs of glomerular renal damage. Of 91 deceased patients, 56 died from COPD and 12 from liver disease. A greatly reduced survival was demonstrated in Pi Z individuals, regardless of sex. Smoking Pi Z individuals had a significantly lower life expectancy than Pi Z non-smokers (p less than 0.01).
alpha 1AT should no longer be ignored by hepatologists with regard to its role in protecting the liver from injury. This protective role needs further definition with regard to protease inhibition, immunologic control, and functional inactivation. Severe deficiency of alpha 1AT clearly predisposes to definable types of liver disease not only in infants and children, but at the other end of the spectrum in elderly adults. It is unfortunate that the pathophysiology of human and animal alpha 1AT related liver injury is not as readily apparent as in pulmonology conditions. However, it is time to digest the tremendous progress that has evolved in that field in relating alpha 1AT to emphysema. Cirrhosis of the liver should be studied in relationship to the pathophysiology demonstrated by our colleagues to be important in "cirrhosis of the lung." The diagnosis of alpha 1AT deficiency and the course of the associated liver disease have been reviewed and updated. Prevention and cure have been demonstrated to be possible but neither method has universal applicability. In contrast, other potential therapeutic endeavors, although not presently proved to be efficacious, with time and research will provide methodologies for the treatment of this disorder as well as insight into mechanisms of general liver injury not previously appreciated.
The TSK/TSK mutation is embryonic lethal; embryos have been reported to die at 7-8 days of gestational age. Crossing TSK/+, IL-4+/- mice revealed that disrupting one or both IL-4 alleles allowed survival of 29 and 47%, respectively, of TSK/TSK mice. These mice failed to develop cutaneous hyperplasia but did exhibit the emphysema that is found in TSK/+ mice. We showed that IL-4 stimulation of fibroblasts increased the level of transforming growth factor-beta (TGF-beta) mRNA and that lungs of TSK/+, IL-4-/- mice had substantially less TGF-beta mRNA than lungs of TSK/+, IL-4+/+ mice. Thus IL-4 seems to regulate the expression of TGF-beta in fibroblasts, providing an explanation for the absence of cutaneous hyperplasia in TSK/+, IL-4Ralpha-/- and TSK/+, TGF-beta+/- mice.