Beatriz Lara

Estimated numbers and prevalence of PI*S and PI*Z alleles of α1-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 α1-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 ≥5 for Southwest, Western and Northern Europe, ≥4 for Central Europe, ≥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.

Results of a case-detection programme for α1-antitrypsin deficiency in COPD patients

α1-Antitrypsin (α1-AT) deficiency is an underdiagnosed condition in patients with chronic obstructive pulmonary disease (COPD). The present authors have conducted a nationwide case detection programme of α1-AT deficiency in unselected patients with COPD using dried blood spots. The first phase analysed samples from 971 patients by determining α1-AT concentrations and identifying the deficient Z allele by genotyping using rapid real-time PCR. The second phase analysed 1,166 samples with α1-AT concentrations and identified both the S and the Z allele, but only in samples with low α1-AT concentrations. A total of eight (0.37%) individuals with the severe deficiency PiZZ were detected. In addition, three patients were identified with the PiSZ genotype in the second phase (0.3%). The global cost of the programme was \#8364;41,512, which represents \#8364;19.42 per sample and \#8364;5,189 per PiZZ detected. A sensitivity analysis demonstrated that performing Z genotype to all samples would have resulted in increased costs of \#8364;28 per sample and \#8364;7,479.5 per PiZZ case identified. In conclusion, a case detection programme of α1-antitrypsin deficiency in patients with chronic obstructive pulmonary disease using dried blood spots is feasible and at a reasonable cost per case detected. Diagnostic yield and costs depend largely on inclusion criteria and the protocol for processing of samples.

Efficacy of alpha1-antitrypsin augmentation therapy in conditions other than pulmonary emphysema

Up to now alpha 1-antitrypsin (AAT) augmentation therapy has been approved only for commercial use in selected adults with severe AAT deficiency-related pulmonary emphysema (i.e. PI*ZZ genotypes as well as combinations of Z, rare and null alleles expressing AAT serum concentrations <11 μmol/L). However, the compassionate use of augmentation therapy in recent years has proven outstanding efficacy in small cohorts of patients suffering from uncommon AAT deficiency-related diseases other than pulmonary emphysema, such as fibromyalgia, systemic vasculitis, relapsing panniculitis and bronchial asthma. Moreover, a series of preclinical studies provide evidence of the efficacy of AAT augmentation therapy in several infectious diseases, diabetes mellitus and organ transplant rejection. These facts have generated an expanding number of medical applications and patents with claims for other indications of AAT besides pulmonary emphysema. The aim of the present study is to compile and analyze both clinical and histological features of the aforementioned published case studies and reports where AAT augmentation therapy was used for conditions other than pulmonary emphysema. Particularly, our research refers to ten case reports and two clinical trials on AAT augmentation therapy in patients with both AAT deficiency and, at least, one of the following diseases: fibromyalgia, vasculitis, panniculitis and bronchial asthma. In all the cases, AAT was successfully applied whereas previous maximal conventional therapies had failed. In conclusion, laboratory studies in animals and humans as well as larger clinical trials should be, thus, performed in order to determine both the strong clinical efficacy and security of AAT in the treatment of conditions other than pulmonary emphysema.

Alpha-1-Antitrypsin Deficiency: Optimal Therapeutic Regimen Based On Population Pharmacokinetics

Background: Exogenous doses of 60 mg/kg α1-antitrypsin (AAT) every 7 days are recommended in patients with severe AAT deficiency. However, long term administration of weekly doses is not well accepted by patients. Using pharmacokinetic simulations, we evaluated whether steady state minimum concentrations of total AAT can be maintained above the threshold of 0.5 g/l with longer intervals between doses. Methods: Several sets of exogenous AAT versus time simulations were studied using a non-linear mixed effect approach with dosage regimens every 7, 14, 21, and 28 days. For each regimen the mean exogenous AAT trough concentrations and 5/95th percentiles were determined. The results obtained were applied to estimate the individual optimal dose at 7, 14, and 21 days in six patients using Bayesian analysis. Results: The simulations showed that a dose of 50 mg/kg AAT every 7 days was sufficient to obtain nadir concentrations. Doses of 120 and 100 mg/kg every 14 days were also adequate, but 180 mg/kg given every 21 days required total AAT monitoring to avoid underdosage. Longer intervals were inappropriate. Dosage individualisation confirmed that AAT infusions given every 14 days maintained the nadir level of 0.5 g/l without a significant dose increase compared with current practice. When the time span between doses was fixed at 21 days, a mean relative AAT dose enhancement of 91% and 13%, respectively, was required to achieve sustained total AAT concentrations above the target level for 100% and 85% of the interval between doses. Conclusions: It is feasible to extend the interval between doses of AAT to 14 or 21 days to achieve adequate trough total AAT concentrations. This study might be used as a starting point for clinical evaluation of the regimens described.

Clinical phenotypes of Italian and Spanish patients with α1-antitrypsin deficiency

With the aim of providing better clinical characterisation of patients with &agr;1-antitrypsin deficiency (AATD), we analysed the data of adult patients with severe AATD enrolled in the Spanish and Italian national registries. We assessed 745 subjects, 416 of whom were enrolled in the Spanish registry and 329 in the Italian registry. 57.2% were male and 64.9% were smokers or former smokers with a mean±sd age of 49.9±13.8 years. Most (81.2%) were index cases, mainly having the PI*ZZ genotype (73.4%), and the mean±sd diagnostic delay was 9.0±12.1 years. Patients with chronic bronchitis were younger, had better preserved lung function and lower tobacco consumption. Overlap patients (chronic obstructive pulmonary disease with asthma) were mainly females, more frequently never-smokers and received respiratory medications more often. 48% of emphysema, 27.5% of chronic bronchitis and 44.8% of overlap subjects were receiving augmentation therapy. Compared with PI*ZZ patients (n=547), the PI*SZ (n=124) subjects were older at diagnosis and had more preserved lung function, despite a higher mean smoking consumption. Early diagnosis of AATD is still an unmet need. Augmentation therapy is administered to similar proportions of patients with different clinical phenotypes. PI*ZZ patients in both registries had more severe respiratory disease than those with PI*SZ, despite lower smoking levels.

Actualización sobre indicaciones de búsqueda activa de casos y tratamiento con alfa-1 antitripsina por vía intravenosa en pacientes con enfermedad pulmonar obstructiva crónica asociada a déficit de alfa-1 antitripsina

The effect of hereditary alpha-1 antitrypsin (AAT) deficiency can manifest clinically in the form of chronic obstructive pulmonary disease (COPD). AAT deficiency (AATD) is defined as a serum concentration lower than 35% of the expected mean value or 50 mg/dl (determined by nephelometry). It is associated in over 95% of cases with Pi*ZZ genotypes, and much less frequently with other genotypes resulting from combinations of Z, S, rare and null alleles. A systematic qualitative review was made of 107 articles, focusing mainly on an active search for AATD in COPD patients and intravenous (iv) treatment with AAT. On the basis of this review, the consultant committee of the Spanish Registry of Patients with AATD recommends that all COPD patients be screened for AATD with the determination of AAT serum concentrations, and when these are low, the evaluation must be completed with phenotyping and, on occasions, genotyping. Patients with severe AATD COPD should receive the pharmacological and non-pharmacological treatment recommended in the COPD guidelines. There is enough evidence from large observational studies and randomized placebo-controlled clinical trials to show that the administration of iv AAT reduces mortality and slows the progression of emphysema, hence its indication in selected cases that meet the inclusion criteria stipulated in international guidelines. The administration of periodic infusions of AAT is the only specific treatment for delaying the progression of emphysema associated with AATD.

Alpha-1 Antitrypsin Deficiency PI*Z and PI*S Gene Frequency Distribution Using on Maps of the World by an Inverse Distance Weighting (IDW) Multivariate Interpolation Method.

1.Background Currently, there is a remarkable lack of genetic epidemiological studies on alpha 1-antitrypsin (AAT) deficiency in about half of the 193 countries of the World. This fact impedes the establishment of a true prevalence pattern of this deleterious hereditary disorder in extensive regions of human population. 2.Objectives The aim of the present study was to generate detailed maps of the frequency distribution of the two most frequent AAT deficiency alleles (i.e., PI*S and PI*Z) in all areas of the World. 3.Materials and Methods Available data provided by epidemiological studies performed in 94 of 193 countries worldwide was used to develop detailed maps of these two alleles, We employed an informatics mathematical approach, namely: the ArcMap [a component of ESRI’s ArcGIS Geographical Information System (GIS), for Microsoft Windows], based on the inverse distance weighting (IDW) multivariate interpolation method, which creates new numerical points from known data, using a simple logarithm based in the distance existing between them 4. Results In this method, PI*S and PI*Z frequencies were represented by colored scales, where qualitative colors were converted into quantitative data, providing information on their distribution in all parts of the world. This approach not only confirmed our previous data, but also provided digital images of the remaining regions of all continents. 5.Conclusions By using this approach, striking differences were found among regions, and unsuspected significant values of the PI*S and PI*Z alleles frequencies were obtained for several geographic regions where have not been studied yet. In fact, some of these regions might be considered as priority targets for further screening studies on AAT deficiency, in order to identify, and properly manage, individuals at risk for the diverse adverse health effects associated with AAT deficiency.

Severe alpha-1 antitrypsin deficiency in composite heterozygotes inheriting a new splicing mutation QOMadrid

BackgroundSevere Alpha-1 Antitrypsin (AAT) deficiency is a hereditary condition caused by mutations in the SERPINA1 gene, which predisposes to lung emphysema and liver disease. It is usually related to PI*Z alleles, and less frequent to rare and null (QO) alleles. Null-AAT alleles represent the end of a continuum of variants associated with profound AAT deficiency and extremely increased risk of emphysema.MethodsA family with severe AAT deficiency was analyzed to achieve genetic diagnosis. The complete exons and introns of the SERPINA1 gene were sequenced and transcriptional analysis by RT-PCR was performed to characterize the effect of splicing variants found in the patients. In addition, a minigene MGserpa1_ex1b-1c was cloned into the pSAD vector to in vitro investigate the independent impact of variants on splicing process.ResultsWe report a new identified null allele (PI*QOMadrid) in two adult siblings with practically no detectable serum AAT. The PI*QOMadrid allele consist of a duplication of the thymine (T) in position +2 of the donor splice site of exon 1C (+2dupT). In these two subjects, PI*QOMadrid occurred in compound heterozygote combination with the previously described variant PI*QOPorto. Both QOMadrid and QOPorto variants are located very close together in a regulatory region of the SERPINA1 gene. Analysis of transcripts revealed that QOMadrid variant prevented the expression of transcripts from exon 1C, and then normally spliced RNA products are not expected in the liver of these patients. In addition, aberrant splicing patterns of both variants were clearly distinguished and quantified by functional in vitro assays lending further support to their pathogenicity.ConclusionFinding pathogenic mutations in non-coding regions of the SERPINA1 highlight the importance that regulatory regions might have in the disease. Regulatory regions should be seriously considered in discordant cases with severe AAT deficiency where no coding mutations were found.

Enhancing physical performance in male volleyball players with a caffeine-containing energy drink.

There are no scientific data about the effects of caffeine intake on volleyball performance. The aim of this study was to investigate the effect of a caffeine-containing energy drink to enhance physical performance in male volleyball players. A double-blind, placebo-controlled, randomized experimental design was used. In 2 different sessions separated by 1 wk, 15 college volleyball players ingested 3 mg of caffeine per kg of body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed volleyball-specific tests: standing spike test, maximal squat jump (SJ), maximal countermovement jump (CMJ), 15-s rebound jump test (15RJ), and agility T-test. Later, a simulated volleyball match was played and recorded. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased ball velocity in the spike test (73 ± 9 vs 75 ± 10 km/h, P < .05) and the mean jump height in SJ (31.1 ± 4.3 vs 32.7 ± 4.2 cm, P < .05), CMJ (35.9 ± 4.6 vs 37.7 ± 4.4 cm, P < .05), and 15RJ (29.0 ± 4.0 vs 30.5 ± 4.6 cm, P < .05). The time to complete the agility test was significantly reduced with the caffeinated energy drink (10.8 ± 0.7 vs 10.3 ± 0.4 s, P < .05). In addition, players performed successful volleyball actions more frequently (24.6% ± 14.3% vs 34.3% ± 16.5%, P < .05) with the ingestion of the caffeinated energy drink than with the placebo drink during the simulated game. A caffeine-containing energy drink, with a dose equivalent to 3 mg of caffeine per kg body mass, might be an effective ergogenic aid to improve physical performance and accuracy in male volleyball players.

Neutrophilic panniculitis associated with alpha‐1‐antitrypsin deficiency: an update

Neutrophilic panniculitis associated with alpha‐1‐antitrypsin deficiency (AATD) is a very rare disease. Its estimated prevalence is 1 in 1000 subjects with severe AATD (usually white individuals with a Pi*ZZ genotype). It is manifested clinically by painful recurrent ulcerating subcutaneous nodules, and characterized histologically by dense infiltrates of neutrophils in the deep dermis and connective‐tissue septae, with secondary lobular panniculitis. It may be the only clinical manifestation of AATD, although it can also occur together with the classical pulmonary or hepatic manifestations of the disease. AATD‐associated panniculitis is not only very rare but may also be significantly underdiagnosed. The physician managing a case of panniculitis with a clinical presentation suggestive of AATD and a compatible skin biopsy should measure serum AAT concentration and, if low, determine the AAT phenotype by isoelectric focusing. If uncertainty remains, the SERPINA1 gene should be sequenced to identify the genotype. If AATD is diagnosed, AATD testing of first‐degree family members should be performed in order to take appropriate preventive and therapeutic measures, including genetic counselling, education on inheritance, risk arising from tobacco smoke, occupational exposure to pollutants and hepatotoxic substances, and the provision of information on clinical management. Cases of panniculitis in which conventional therapy with dapsone has failed may be managed with intravenous augmentative therapy using human AAT. The current manuscript addresses the fundamental concepts of the pathogenesis of AATD‐associated panniculitis and describes the clinical presentation and management of cases in order to reduce underdiagnosis and improve outcomes.