Alpha-1 antitrypsin deficiency

Alpha-1 antitrypsin deficiency (AATD) is a rare hereditary condition caused by decreased plasma and tissue levels of alpha-1 antitrypsin (AAT) that can lead to serious lung and liver disease in children and adults. AATD patients face challenges such as under diagnosis, clinical variability, and limited treatment options for liver disease. Early detection and biomarkers for predicting outcomes are needed to improve patient outcome. Currently, the only approved pharmacological therapy is augmentation therapy, which can delay the progression of emphysema. However, alternative strategies such as gene therapy, induced pluripotent stem cells, and prevention of AAT polymerization inside hepatocytes are being investigated. This review aims to summarize and update current knowledge on AATD, identify areas of controversy, and formulate questions for further research. (AU)

El déficit de alfa-1 antitripsina (DAAT) es una enfermedad hereditaria poco frecuente causada por la disminución de los niveles plasmáticos y tisulares de alfa-1 antitripsina (AAT) que puede provocar enfermedades pulmonares y hepáticas graves en niños y adultos. Aquellos con DAAT se enfrentan a retos como el infradiagnóstico, la variabilidad clínica y a las limitadas opciones de tratamiento para la enfermedad hepática. La detección precoz y los biomarcadores para predecir los resultados clínicos son necesarios para mejorar la evolución de los pacientes. En la actualidad, el único tratamiento farmacológico aprobado es la terapia de reposición, que puede retrasar la progresión del enfisema. Sin embargo, se están investigando estrategias alternativas como la terapia génica, las células madre pluripotentes inducidas y la prevención de la polimerización de la AAT en el interior de los hepatocitos. Esta revisión pretende resumir y actualizar los conocimientos actuales sobre la AATD, identificar las áreas de controversia y formular preguntas para futuras investigaciones. (AU)

Alpha-1 antitrypsin deficiency.

Alpha-1 antitrypsin deficiency (AATD) is a rare hereditary condition caused by decreased plasma and tissue levels of alpha-1 antitrypsin (AAT) that can lead to serious lung and liver disease in children and adults. AATD patients face challenges such as under diagnosis, clinical variability, and limited treatment options for liver disease. Early detection and biomarkers for predicting outcomes are needed to improve patient outcome. Currently, the only approved pharmacological therapy is augmentation therapy, which can delay the progression of emphysema. However, alternative strategies such as gene therapy, induced pluripotent stem cells, and prevention of AAT polymerization inside hepatocytes are being investigated. This review aims to summarize and update current knowledge on AATD, identify areas of controversy, and formulate questions for further research.

miR-320c Regulates SERPINA1 Expression and Is Induced in Patients With Pulmonary Disease / El miR-320c regula la expresión del gen SERPINA1 y se induce en pacientes con enfermedad pulmonar

Introduction: Alpha-1 antitrypsin deficiency (AATD) is a genetic condition resulting in lung and liver disease with a great clinical variability. MicroRNAs have been identified as disease modifiers; therefore miRNA deregulation could play an important role in disease heterogeneity. Members of miR-320 family are involved in regulating of multiple processes including inflammation, and have potential specific binding sites in the 3′UTR region of SERPINA1 gene. In this study we explore the involvement of miR-320c, a member of this family, in this disease. Methods: Firstly in vitro studies were carried out to demonstrate regulation of SERPINA1 gene by miR-320. Furthermore, the expression of miR-320c was analyzed in the blood of 98 individuals with different AAT serum levels by using quantitative PCR and expression was correlated to clinical parameters of the patients. Finally, HL60 cells were used to analyze induction of miR-320c in inflammatory conditions. Results: Overexpression of miR-320 members in human HepG2 cells led to inhibition of SERPINA1 expression. Analysis of miR-320c expression in patient's samples revealed significantly increased expression of miR-320c in individuals with pulmonary disease. Additionally, HL60 cells treated with the pro-inflammatory factor lipopolysaccharide (LPS) showed increase in miR-320c expression, suggesting that miR-320c responds to inflammation. Conclusion: Our findings demonstrate that miR-320c inhibits SERPINA1 expression in a hepatic cell line and its levels in blood are associated with lung disease in a cohort of patients with different AAT serum levels. These results suggest that miR-320c can play a role in AAT regulation and could be a biomarker of inflammatory processes in pulmonary diseases. (AU)

Introducción: La deficiencia de alfa-1 antitripsina (DAAT) es una condición genética que produce enfermedad pulmonar y hepática con una gran variabilidad clínica. Los microARN se han identificado como modificadores de la gravedad de algunas enfermedades y su desregulación podría desempeñar un papel en la heterogeneidad de esta enfermedad. Los miembros de la familia miR-320 regulan múltiples procesos, incluyendo la inflamación, y tienen lugares de unión en la región 3’UTR del gen SERPINA1. En este estudio exploramos la implicación del miR-320c, un miembro de esta familia, en la DAAT. Métodos: Primero se realizaron estudios in vitro para demostrar la regulación del gen SERPINA1 por parte del miR-320. Además, se analizó la expresión de miR-320c en la sangre de 98 individuos con diferentes niveles de AAT mediante PCR cuantitativa y se correlacionó con los parámetros clínicos. Por último, se utilizaron células HL60 para analizar la inducción de miR-320c en condiciones inflamatorias. Resultados: La sobreexpresión del miR-320 en células HepG2 inhibía la expresión del gen SERPINA1. El análisis de expresión de miR-320c en los pacientes reveló una expresión significativamente aumentada en los casos con enfermedad pulmonar. Por otro lado, las células HL60 tratadas con LPS como factor proinflamatorio mostraron un aumento de expresión de miR-320c, lo que sugiere que este miARN responde a procesos inflamatorios. Conclusión: Nuestros resultados demuestran que el miR-320c inhibe la expresión de SERPINA1 en células hepáticas y que sus niveles en sangre están asociados con la presencia de enfermedad pulmonar en pacientes con diferentes niveles de AAT. Esto sugiere que el miR-320c desempeña un papel en la regulación de los niveles de AAT y podría ser un biomarcador de inflamación en enfermedades pulmonares. (AU)

miR-320c Regulates SERPINA1 Expression and Is Induced in Patients With Pulmonary Disease.

INTRODUCTION: Alpha-1 antitrypsin deficiency (AATD) is a genetic condition resulting in lung and liver disease with a great clinical variability. MicroRNAs have been identified as disease modifiers; therefore miRNA deregulation could play an important role in disease heterogeneity. Members of miR-320 family are involved in regulating of multiple processes including inflammation, and have potential specific binding sites in the 3'UTR region of SERPINA1 gene. In this study we explore the involvement of miR-320c, a member of this family, in this disease. METHODS: Firstly in vitro studies were carried out to demonstrate regulation of SERPINA1 gene by miR-320. Furthermore, the expression of miR-320c was analyzed in the blood of 98 individuals with different AAT serum levels by using quantitative PCR and expression was correlated to clinical parameters of the patients. Finally, HL60 cells were used to analyze induction of miR-320c in inflammatory conditions. RESULTS: Overexpression of miR-320 members in human HepG2 cells led to inhibition of SERPINA1 expression. Analysis of miR-320c expression in patient's samples revealed significantly increased expression of miR-320c in individuals with pulmonary disease. Additionally, HL60 cells treated with the pro-inflammatory factor lipopolysaccharide (LPS) showed increase in miR-320c expression, suggesting that miR-320c responds to inflammation. CONCLUSION: Our findings demonstrate that miR-320c inhibits SERPINA1 expression in a hepatic cell line and its levels in blood are associated with lung disease in a cohort of patients with different AAT serum levels. These results suggest that miR-320c can play a role in AAT regulation and could be a biomarker of inflammatory processes in pulmonary diseases.

Deficiencia de alfa-1 antitripsina y neumotórax espontáneo. ¿Solo una coincidencia? / Alpha-1 antitrypsin deficiency and spontaneous pneumothorax. Just a coincidence?

Resumen La deficiencia de alfa-1 antitripsina (AAT) es uno de los trastornos hereditarios más frecuentes y con mayor incidencia en pacientes con enfermedad pulmonar obstructiva crónica (EPOC). Se desconoce su prevalencia en aquellos con neumotórax espontáneo. El objetivo fue estimar la prevalencia de deficiencia de AAT en sujetos con neumotórax espontáneo. El estudio fue prospectivo y de corte transversal en pacientes con neumotórax espontáneo primario. Se excluyeron aquellos con neumotórax secundario. Se realizó cuantificación de AAT en suero por nefelometría y posterior genotipificación rápida (PCR en tiempo real) para detectar los alelos de deficiencia más prevalentes (Z y S) en aquellos con concentraciones séricas ≤ 120 mg/dl. Se incluyeron 58 pacientes con neumotórax espontáneo primario. La edad promedio fue de 34 ± 13 años con predominio de sexo masculino (72%) y alta prevalencia de tabaquismo actual y pasado (60%). Del total, el 26% (IC95%: 15-39) presentó concentraciones de AAT ≤ 120mg/dl. Encontramos 7 formas deficitarias (12%; IC 95%: 5-23%). Un paciente presentó una forma grave Pi*ZZ (1.7%), 3 fueron heterocigotos Z (5.2%) y 3 heterocigotos S (5.2%). La prevalencia de variantes deficitarias de AAT fue alta en este grupo con neumotórax espontáneo.

Abstract Alpha-1 antitrypsin (AAT) deficiency is one of the most common inherited disorders with a higher incidence in patients with chronic obstructive pulmonary disease (COPD). Its prevalence in patients with spontaneous pneumothorax is unknown. The objective was to estimate the prevalence of AAT deficiency in patients with spontaneous pneumothorax. This was a prospective cross-sectional study, in patients with spontaneous pneumothorax, where those with secondary pneumothorax were excluded. Quantification of serum AAT by nephelometry and subsequent rapid genotyping (real time PCR) was performed, in order to detect the most prevalent deficiency alleles (Z and S) in those subjects with serum AAT concentrations ≤ 120 mg/dl. Fifty-eight patients with primary spontaneous pneumothorax were included. The average age was 34 ± 13 years with male predominance (72%) and high prevalence of current and past smoking (60%). Twenty six percent of them (95% CI: 15-39) presented AAT serum concentrations ≤ 120mg/dl. We found 7 deficiency variants (12%; IC 95%: 5-23%). One patient presented a severe Pi*ZZ form (1.7%), 3 were heterozygotes Z (5.2%) and 3 heterozygotes S (5.2%). The prevalence of AAT deficient variants was high in patients with spontaneous pneumothorax.

miR-320c Regulates SERPINA1 Expression and Is Induced in Patients With Pulmonary Disease.

INTRODUCTION: Alpha-1 antitrypsin deficiency (AATD) is a genetic condition resulting in lung and liver disease with a great clinical variability. MicroRNAs have been identified as disease modifiers; therefore miRNA deregulation could play an important role in disease heterogeneity. Members of miR-320 family are involved in regulating of multiple processes including inflammation, and have potential specific binding sites in the 3'UTR region of SERPINA1 gene. In this study we explore the involvement of miR-320c, a member of this family, in this disease. METHODS: Firstly in vitro studies were carried out to demonstrate regulation of SERPINA1 gene by miR-320. Furthermore, the expression of miR-320c was analyzed in the blood of 98 individuals with different AAT serum levels by using quantitative PCR and expression was correlated to clinical parameters of the patients. Finally, HL60 cells were used to analyze induction of miR-320c in inflammatory conditions. RESULTS: Overexpression of miR-320 members in human HepG2 cells led to inhibition of SERPINA1 expression. Analysis of miR-320c expression in patient's samples revealed significantly increased expression of miR-320c in individuals with pulmonary disease. Additionally, HL60 cells treated with the pro-inflammatory factor lipopolysaccharide (LPS) showed increase in miR-320c expression, suggesting that miR-320c responds to inflammation. CONCLUSION: Our findings demonstrate that miR-320c inhibits SERPINA1 expression in a hepatic cell line and its levels in blood are associated with lung disease in a cohort of patients with different AAT serum levels. These results suggest that miR-320c can play a role in AAT regulation and could be a biomarker of inflammatory processes in pulmonary diseases.

Prevalence of Alpha-1 Antitrypsin Deficiency in COPD Patients in Argentina. The DAAT.AR Study. / Prevalencia de déficit de alfa-1 antitripsina en pacientes con EPOC en Argentina. Estudio DAAT.AR.

INTRODUCTION: Alpha-1 antitrypsin deficiency (AATD) is still underdiagnosed, despite the recommendation to determine AAT in patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE: To estimate the prevalence of AATD in COPD patients adjusted according to the population of the COPD prevalence study in Argentina (EPOC.AR). MATERIAL AND METHODS: This was a multicenter prospective cross-sectional study of a population aged≥30 years of age diagnosed with COPD, involving AAT quantification in dry blood spot and subsequent genotyping in subjects with<1.5mg/dL AAT in dry blood spot (<80mg/dL in serum). AAT was defined as the detection of variants ZZ or SZ on genotyping. The EPOC.AR study population was used to calculate local adjusted prevalence. RESULTS: We included 3,254 patients (544 with AAT<80mg/dL) with a spirometric diagnosis of COPD. The prevalence of AATD in the total study population was 1.29% (95% CI 0.93-1.74), of which 0.92% (95% CI 0.62-1.31) were Pi*ZZ and 0.37% (95% CI 0.19-0.64) Pi*SZ. The adjusted prevalence of AATD in COPD patients≥40 years of age was 0.83% (95% CI 0.23-2.08). We found that AATD was negatively associated with age (OR 0.94; 95% CI 0.90-0.98; P=.006), smoking habit (OR 0.98; 95% CI 0.96-0.99; P=.009), and FEV1% (OR 0.95; 95% CI 0.91-0.99; P=.015). CONCLUSIONS: The prevalence of AATD in the adult population with COPD in Argentina is estimated to be 0.83%, which could represent 17,000 cases in our country.

Programa de cribado para el déficit De alfa 1-antitripsina en el servicio de neumonología del Hospital Tránsito Cáceres de Allende / Alpha-1-antitrypsin deficiency screening program at the Pneumonology Department of Hospital Tránsito Cáceres de Allende

El déficit de alfa -1 Antitripsina (DAAT) es una enfermedad genética rara, asociada a un incremento a padecer enfisema pulmonar y hepatopatía crónicas en niños y adultos, frecuentemente subdiagnosticada, con largos retrasos entre el inicio de los síntomas y el diagnóstico definitivo. La alfa 1-antitripsina (AAT) es el inhibidor de proteasas más abundante en el organismo humano. Se considera déficit grave y es a lo que habitualmente se refiere la literatura científica a los siguientes fenotipos: SZ, ZZ y Null. Es necesario programas de cribado para su detección precoz, por lo que se ha descripto y validado un método sencillo y específico, mediante el cual se cuantifica el valor de AAT por nefelometría en muestras de gota de sangre en papel secante y se realiza genotipificación rápida de las variantes Z y S. Objetivos: Determinar la proporción de individuos con DAAT en una población de pacientes con enfermedades respiratorias crónicas. Identificar y caracterizar a aquellos con déficit de AAT. Materiales y Método: Estudio Observacional, Descriptivo de corte Transversal de cribado de déficit de AAT, entre el 2 de enero de 2014 a 30 de marzo de 2015. De 80 personas que cumplieron con los criterios de inclusión y que concurrieron de forma espontánea o por derivación al Servicio de Neumonología del Hospital Tránsito Cáceres de Allende, Córdoba, Argentina, se analizaron 62 pacientes que aceptaron realizarse el estudio. Se realizó dosaje de alfa1-antitripsina mediante gota de sangre en papel secante a los pacientes que cumplieron los criterios de inclusión. Se solicitó espirometría, Tomografía Computada de Tórax de Alta Resolución y genotipificación rápida solo a aquellos pacientes con valores de alfa 1-antitripsina < 1,8 mg/dL. Resultados: En el presente trabajo se estudió un total de 62 pacientes, 28 (45,2%) fueron de sexo femenino y 34 (54,8%) de sexo masculino, 37 (59,7%) tuvieron valores de alfa 1-antitripsina ≥ 1,8 mg/dL y 25 (40,3%) < 1,8 mg/dL. La obtención del genotipo por la técnica de gota seca a 25 (40,3%; 25:62) pacientes con valores < 1,8 mg/dL mostró que: 22 (88%; 22:25) fueron NoS NoZ, 2 (8%; 2:25) Heterocigoto para Z y 1 (4%; 1:25) Heterocigoto para S. El patrón espirométrico predominante según criterio de ATS/ERS fue el obstructivo (88%). El patrón en TCAR fue de enfisema en 22 pacientes (88%): 7 (31,8%) centrolobulillar, 8 (36,4%) paraseptal, 7 (31,8%) panlobulillar. Hubo 2 pacientes (8%) con bronquiectasias, y 1 (4%) fue normal. Conclusión: En una población seleccionada por síntomas y/o antecedentes se pueden identificar con el cribado con técnica de gota seca a pacientes con DAAT, que en su expresión grave es poco frecuente en la Argentina, probablemente subdiagnosticado, siendo superior el número de portadores heterocigotos PIS y PIZ. El diagnóstico precoz de DAAT es poco frecuente. Es difícil establecer conclusiones sobre el grupo de alfa 1-antitripsina <1,8 mg/dL sin ser deficiencias graves, en relación a las variables estudiadas en la muestra debido a la escases de estudios y bibliografía encontradas sobre el tema. Consideramos que los pacientes que presentan un genotipo No S No Z y los que presentan discordancia deben ser confirmados cuantitativamente y tener una caracterización del fenotipo en muestras de suero por Isoelectoenfoque y ocasionalmente el análisis molecular del gen para variantes alélicas poco frecuentes, nuevas o nulas.

[Detection of alpha-1 antitrypsin deficiency: A study on patients diagnosed with chronic obstructive pulmonary disease in primary health care]. / Detección del déficit de alfa-1 antitripsina: estudio en pacientes con enfermedad pulmonar obstructiva crónica diagnosticados en atención primaria.

The prevalence of chronic obstructive pulmonary disease (COPD) in Spain is 10.2%. Although tobacco is the main aetiological factor, biomass smoke exposure and alpha-1 antitrypsin deficiency (AATD) have also been related to its development. AATD is a genetic condition which could be causing 2-3% of COPD cases. The aim of this cross-sectional descriptive study was to exclude the existence of AATD in a population of COPD patients from CS Culleredo, A Coruña. The thick blood drop test on blotting paper, as well as the analysis of the mutations PI*S and PI*Z of the gene SERPINA 1 by the analysis of denaturing gradients after simultaneous amplification related to PCR (polymerase chain reaction). The study population included 80 patients between 40-80 years old, of whom 30% were carriers of a deficient allele (heterozygous), and 80% of them were the allele PiS. Only one PiSZ (1.25%) individual and no PiZZ was detected. This represents an allelic frequency of 3.1% (PiZ), and 13.1% (PiS). The detected allelic frequencies are higher than previously reported in the Spanish population. Severe AATD has been excluded in 98.75% of the study population. The Pi*SZ patient has been diagnosed in an early stage of the disease. We have also achieved one of the quality indicators recommended by GesEPOC. Our area has shown a high PiS and PiZ frequency, thus our study could be used as a reference for further research in the Galician population.

Alpha-1 Antitrypsin Deficiency in COPD Patients: A Cross-Sectional Study.

INTRODUCTION: Alpha-1 antitrypsin deficiency (AATD) is a genetic disorder associated with early onset chronic obstructive pulmonary disease (COPD) and liver disease. It is also a highly under-diagnosed condition. As early diagnosis could prompt specific interventions such as smoking cessation, testing of family members, genetic counselling and use of replacement therapy, screening programs are needed to identify affected patients. OBJECTIVE: To estimate the prevalence of severe AATD in COPD patients by routine dried blood spot testing and subsequent genotyping in patients with alpha-1 antitrypsin (AAT) levels below an established threshold. MATERIALS AND METHODS: Cross-sectional study of adult COPD patients attending the Hospital Dr. Antonio Cetrángolo (Buenos Aires, Argentina) between 2009 and 2012. The study consisted of capillary blood collection via finger stick to determine AAT levels, clinical evaluation and lung function tests. Genotype was determined in AAT-deficient patients. RESULTS: A total of 1,002 patients were evaluated, of whom 785 (78.34%) had normal AAT levels, while low AAT levels were found in 217 (21.66%). Subsequent genotyping of the latter sub-group found: 15 (1.5%, 95% CI 0.75-2.25) patients with a genotype associated with severe AATD, of whom 12 were ZZ (1.2%, 95% CI 0.52-1.87) and 3 SZ (0.3%, 95% CI 0-0.64). The remaining 202 patients were classified as: 29 Z heterozygotes (2.89%, 95% CI 1.86-3.93), 25 S heterozygotes (2.5%, 95% CI 1.53-3.46) and 4 SS (0.4%, 95% CI 0.01-0.79). A definitive diagnosis could not be reached in 144 patients (14.37%, 95% CI 12.2-16.54). CONCLUSION: The strategy using an initial serum AAT level obtained by dried blood spot testing and subsequent genotyping was a satisfactory initial approach to a screening program for severe AAT, as a definitive diagnosis was achieved in 87% of patients. However, results were not obtained for logistical reasons in the remaining 13%. This major obstacle may be overcome by the use of dried blood spot phenotyping techniques. We believe this approach for detecting AATD in COPD patients, in compliance with national and international guidelines, is supported by our results.

Characteristics of candidates for lung transplantation due to chronic obstructive pulmonary disease and alpha-1 antitrypsin deficiency emphysema.

INTRODUCTION: COPD and emphysema due to alpha-1 antitrypsin deficiency (AATD) are the first and fourth indications for lung transplantation worldwide, respectively. Despite this, there is little information regarding the health status of these patients at the time of transplantation. METHODS: Patients who received a lung transplant in the Hospital Vall d'Hebron between July 1993 and August 2013 were identified and data from the evaluation prior to the transplant were collected. RESULTS: A total of 217 patients who received a lung transplant for COPD and 19 in whom the indication was AATD were included. These patients were severely impaired at the time of the evaluation for lung transplantation, although the trend in recent years has been to evaluate patients at earlier stages of the disease. Baseline characteristics were similar in both groups except that patients with AATD were younger [43 (7.7) vs. 53.6 (6.1) years old, P<.001], with less exposure to tobacco [23.9 (15) vs. 50 (29) packs-year, P<002] and lower PCO2 [41.7 (7.6) vs. 47.9 (9.7) mmHg, P<.004]. CONCLUSIONS: The number of patients receiving a lung transplant for COPD has progressively increased and the tendency is to perform the evaluation in earlier stages of the disease. Patients receiving transplants for COPD and AATD had similar characteristics at the time of the evaluation, although AATD patients were younger and had less exposure to tobacco and lower PCO2.

Description of alpha-1-antitrypsin deficiency associated with PI*Q0ourém allele in La Palma Island (Spain) and a genotyping assay for its detection.

By analysis of a case of discrepancy between serum alpha-1-antitrypsin (AAT) level and genotype for the most common defective alleles associated with AAT deficiency (PI*S and PI*Z), a patient carrying the allele PI*Q0ourém has been identified for the first time outside of Portugal. This null allele has been implicated in cases of severe pulmonary emphysema. After developing a clinical assay for detection of c.1130insT mutation, based on fluorescent probes (HybProbe®), another 4 carriers of PI*Q0ourém allele were identified among 43 patients with abnormally low serum AAT levels based on their genotypes for PI*S and PI*Z alleles. Since 4 out 5 cases are from the same locality (La Palma Island, Spain), it is advisable to conduct genetic analyses of affected families and, possibly, a focused population screening.

Indications for active case searches and intravenous alpha-1 antitrypsin treatment for patients with alpha-1 antitrypsin deficiency chronic pulmonary obstructive disease: an update.

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.

Normativas de diagnóstico y tratamiento del déficit de alfa-1 antitripsina / Guidelines on Diagnosis and Treatment of Alpha-1 Antitrypsin Deficiency

El déficit de alfa-1 antitripsina (AAT) es una condición hereditaria rara y raramente diagnosticada en todo el mundo, incluida Argentina. El infradiagnóstico es fundamentalmente debido a que muchos médicos desconocen su existencia, diagnóstico y tratamiento. Por ello, la Asociación Argentina de Medicina Respiratoria encomendó a un grupo de expertos la elaboración de la presente normativa. La AAT es una glicoproteína secretada por el hígado, muy abundante en sangre, tejidos y fluidos corporales, cuya función principal consiste en inhibir la elastasa del neutrófilo y otras serin proteasas, confiriendo al suero humano más del 90% de su capacidad antiproteasa. El déficit de AAT deriva de mutaciones del gen de la SERPINA1, y se manifiesta clínicamente por enfisema pulmonar, cirrosis hepática y, con menor frecuencia, por paniculitis, vasculitis sistémicas y posiblemente otras enfermedades. El déficit grave de AAT afecta mayoritariamente a individuos de raza caucasiana y tiene su máxima prevalencia (1:2.000-1:5.000 individuos) en el norte, oeste y centro de Europa. En EEUU y Canadá, la prevalencia es de 1: 5.000-10.000, y es 5 veces menor en países latinoamericanos, incluida Argentina, donde se estima que puede haber unos 18.000 individuos con genotipos deficientes graves SZ y ZZ, la inmensa mayoría sin diagnosticar. Sospechar la enfermedad resulta clave para medir la concentración sérica de AAT y completar el diagnóstico con la determinación del fenotipo o genotipo ante concentraciones bajas. La detección de casos permite la puesta en práctica del consejo genético, el chequeo de familiares consanguíneos y, en casos seleccionados, la aplicación de terapia sustitutiva.

The alpha-1 antitrypsin (AAT) deficiency is a rare hereditary condition which is rarely diagnosed in the world, including Argentina. Underdiagnosis is mainly due to lack of knowledge of its diagnosis and treatment by many physicians. For this reason, the Argentine Association of Respiratory Medicine convened a group of experts to develop the present guidelines. AAT is a glycoprotein secreted by the liver; it reaches high levels in blood, body tissues and fluids. Its main function is to inhibit the neutrophil elastase and other serum proteases providing 90% of human serine antiprotease activity. The AAT deficiency is produced by mutations of the SERPINA1 gene. Its clinical manifestations are pulmonary emphysema, liver cirrhosis, and less often panniculitis, systemic vasculitis and possibly other conditions. The severe AAT deficiency affects mainly Caucasian individuals. The highest prevalence, ranging from 1 in 2000 to 1 in 5000 population is observed in northern, western and central Europe. In the USA and Canada, the prevalence varies from 1 in 5000 to 1 in 10000 population. It is 5 times less frequent in Latin American countries. It is estimated that in Argentina there may be 18000 cases with severe deficiency of SZ y ZZ genotypes, most of them undiagnosed. It is crucial to suspect the disease in order to measure the serum AAT concentration, and, if the concentrations are low, to confirm the diagnosis with the phenotype or genotype determinations. Case detection allows genetic advice, control of blood-related relatives and in selected cases, replacement therapy.

Normativas de diagnóstico y tratamiento del déficit de alfa-1 antitripsina

El déficit de alfa-1 antitripsina (AAT) es una condición hereditaria rara y raramente diagnosticada en todo el mundo, incluida Argentina. El infradiagnóstico es fundamentalmente debido a que muchos médicos desconocen su existencia, diagnóstico y tratamiento. Por ello, la Asociación Argentina de Medicina Respiratoria encomendó a un grupo de expertos la elaboración de la presente normativa. La AAT es una glicoproteína secretada por el hígado, muy abundante en sangre, tejidos y fluidos corporales, cuya función principal consiste en inhibir la elastasa del neutrófilo y otras serin proteasas, confiriendo al suero humano más del 90% de su capacidad antiproteasa. El déficit de AAT deriva de mutaciones del gen de la SERPINA1, y se manifiesta clínicamente por enfisema pulmonar, cirrosis hepática y, con menor frecuencia, por paniculitis, vasculitis sistémicas y posiblemente otras enfermedades. El déficit grave de AAT afecta mayoritariamente a individuos de raza caucasiana y tiene su máxima prevalencia (1:2.000-1:5.000 individuos) en el norte, oeste y centro de Europa. En EEUU y Canadá, la prevalencia es de 1: 5.000-10.000, y es 5 veces menor en países latinoamericanos, incluida Argentina, donde se estima que puede haber unos 18.000 individuos con genotipos deficientes graves SZ y ZZ, la inmensa mayoría sin diagnosticar. Sospechar la enfermedad resulta clave para medir la concentración sérica de AAT y completar el diagnóstico con la determinación del fenotipo o genotipo ante concentraciones bajas. La detección de casos permite la puesta en práctica del consejo genético, el chequeo de familiares consanguíneos y, en casos seleccionados, la aplicación de terapia sustitutiva.(AU)

The alpha-1 antitrypsin (AAT) deficiency is a rare hereditary condition which is rarely diagnosed in the world, including Argentina. Underdiagnosis is mainly due to lack of knowledge of its diagnosis and treatment by many physicians. For this reason, the Argentine Association of Respiratory Medicine convened a group of experts to develop the present guidelines. AAT is a glycoprotein secreted by the liver; it reaches high levels in blood, body tissues and fluids. Its main function is to inhibit the neutrophil elastase and other serum proteases providing 90% of human serine antiprotease activity. The AAT deficiency is produced by mutations of the SERPINA1 gene. Its clinical manifestations are pulmonary emphysema, liver cirrhosis, and less often panniculitis, systemic vasculitis and possibly other conditions. The severe AAT deficiency affects mainly Caucasian individuals. The highest prevalence, ranging from 1 in 2000 to 1 in 5000 population is observed in northern, western and central Europe. In the USA and Canada, the prevalence varies from 1 in 5000 to 1 in 10000 population. It is 5 times less frequent in Latin American countries. It is estimated that in Argentina there may be 18000 cases with severe deficiency of SZ y ZZ genotypes, most of them undiagnosed. It is crucial to suspect the disease in order to measure the serum AAT concentration, and, if the concentrations are low, to confirm the diagnosis with the phenotype or genotype determinations. Case detection allows genetic advice, control of blood-related relatives and in selected cases, replacement therapy.(AU)

Alpha-1-antitrypsin deficiency associated with the Mattawa variant.

The most common deficiency alleles for alpha-1-antitrypsin deficiency (AATD) are Pi*S and Pi*S, but there are also other deficiency variants. This case report describes the first two cases of AATD detected in Spain resulting from the combination of a null Mattawa allele with a normal PI*M, and a rare Mmalton. Both cases were initially diagnosed as Pi*MM by isoelectric focusing (IEF), but the low serum AAT values led us to suspect the existence of rare deficiency alleles that were undetectable using this technique, and to performing molecular analysis of the gene, which provided the correct diagnosis. Inconsistencies between serum AAT values and the phenotype should make one suspect the existence of one of these rare alleles.

Enfisema bulloso bilateral gigante por déficit de alfa1-antitripsina / Giant bilateral bullous emphysema due to deficit of alpha1-antritypsin

Se presenta el caso de una paciente de 48 años de edad con un enfisema bulloso bilateral gigante y niveles bajos de alfa1-antitripsina, determinados en el laboratorio Labcel de la Facultad de Ciencias Médicas Dr Miguel Enríquez. La definición de alfa1-antitriptisina es resultante de un defecto genético y aproximadamente el 75 por ciento de los adultos con una carencia grave de esta proteína desarrollan un enfisema que a menudo comienza antes de los 40 años de edad. Con el objetivo de debatir los resultados de los exámenes complementarios realizados, el tratamiento y la evolución de esta paciente, exponemos este trabajo por considerarlo de importancia para la práctica médico-quirúrgica(AU)

The case of a female patient aged 48 with a giant bilateral bullous emphysema and low levels of alpha1-antitripsine determined at the Labcel laboratory of Dr Miguel Enríquez. Faculty of Medical Sciences was reported. The definition of alpha1-antitrypsin is the result of a genetical defect and approximately 75 percent of the adults with a severe lack of this protein develop an emphysema that often begins before the 40 years of age. In order to discuss the results of the complementary tests, the treatment and evolution of this patient, we present this paper for considering it important for the medicosurgical practice(AU)

Enfisema bulloso bilateral gigante por déficit de alfa1-antitripsina / Giant bilateral bullous emphysema due to deficit of alpha1-antritypsin

Se presenta el caso de una paciente de 48 años de edad con un enfisema bulloso bilateral gigante y niveles bajos de alfa1-antitripsina, determinados en el laboratorio Labcel de la Facultad de Ciencias Médicas Dr Miguel Enríquez. La definición de alfa1-antitriptisina es resultante de un defecto genético y aproximadamente el 75 por ciento de los adultos con una carencia grave de esta proteína desarrollan un enfisema que a menudo comienza antes de los 40 años de edad. Con el objetivo de debatir los resultados de los exámenes complementarios realizados, el tratamiento y la evolución de esta paciente, exponemos este trabajo por considerarlo de importancia para la práctica médico-quirúrgica(AU)

The case of a female patient aged 48 with a giant bilateral bullous emphysema and low levels of alpha1-antitripsine determined at the Labcel laboratory of Dr Miguel Enríquez. Faculty of Medical Sciences was reported. The definition of alpha1-antitrypsin is the result of a genetical defect and approximately 75 percent of the adults with a severe lack of this protein develop an emphysema that often begins before the 40 years of age. In order to discuss the results of the complementary tests, the treatment and evolution of this patient, we present this paper for considering it important for the medicosurgical practice(AU)