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

Spanish Registry of Patients With Alpha-1 Antitrypsin Deficiency: Database Evaluation and Population Analysis

INTRODUCTION AND OBJECTIVE

REDAAT, the Spanish Registry of Patients with Alpha-1 Antitrypsin Deficiency, was set up in order to improve knowledge of this disease. This study is an evaluation of the registry and an analysis of its patient population.

METHODS

The registry has a database hosted on the website www.redaat.es. It collects clinical and functional data on patients with PiSZ, ZZ phenotypes and other rare variants.

RESULTS

Thanks to the collaboration of 124 physicians, the registry currently contains information on 511 individuals from 103 healthcare centers. Of these 511, 348 (74.2%) are Pi*ZZ homozygotes, and 100 (19.5%) are Pi*SZ heterozygotes. More cases are seen in tertiary level hospitals. A total of 81% of the cases have respiratory disease, and a lower proportion of AATD cases were detected by family screening or liver disease. Follow-up data are available for 45% of the cases, and 35% received alpha-1 antitripsin replacement therapy.

CONCLUSIONS

The REDAAT registry is a useful tool for obtaining quality information about this minority disease in routine clinical practice conditions, although it is difficult to obtain follow-up data, and the representativeness of the sample included cannot be determined.

Gene and miRNA expression profiles in PBMCs from patients with severe and mild emphysema and PiZZ alpha1-antitrypsin deficiency

INTRODUCTION

COPD has complex etiologies involving both genetic and environmental determinants. Among genetic determinants, the most recognized is a severe PiZZ (Glu342Lys) inherited alpha1-antitrypsin deficiency (AATD). Nonetheless, AATD patients present a heterogeneous clinical evolution, which has not been completely explained by sociodemographic or clinical factors. Here we performed the gene expression profiling of blood cells collected from mild and severe COPD patients with PiZZ AATD. Our aim was to identify differences in messenger RNA (mRNA) and microRNA (miRNA) expressions that may be associated with disease severity.

MATERIALS AND METHODS

Peripheral blood mononuclear cells from 12 COPD patients with PiZZ AATD (6 with severe disease and 6 with mild disease) were used in this pilot, high-throughput microarray study. We compared the cellular expression levels of RNA and miRNA of the 2 groups, and performed functional and enrichment analyses using the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene-ontology (GO) terms. We also integrated the miRNA and the differentially expressed putative target mRNA. For data analyses, we used the R statistical language R Studio (version 3.2.5).

RESULTS

The severe and mild COPD-AATD groups were similar in terms of age, gender, exacerbations, comorbidities, and use of augmentation therapy. In severe COPD-AATD patients, we found 205 differentially expressed genes (DEGs) (114 upregulated and 91 downregulated) and 28 miRNA (20 upregulated and 8 downregulated) compared to patients with mild COPD-AATD disease. Of these, hsa-miR-335-5p was downregulated and 12 target genes were involved in cytokine signaling, MAPK/mk2, JNK signaling cascades, and angiogenesis were much more highly expressed in severe compared with mild patients.

CONCLUSIONS

Despite the small sample size, we identified downregulated miRNA (hsa-miR-335) and the activation of pathways related to inflammation and angiogenesis on comparing patients with severe vs mild COPD-AATD. Nonetheless, our findings warrant further validation in large studies.

Spanish Registry of Patients With Alpha-1 Antitrypsin Deficiency: Database Evaluation and Population Analysis

INTRODUCTION AND OBJECTIVE

REDAAT, the Spanish Registry of Patients with Alpha-1 Antitrypsin Deficiency, was set up in order to improve knowledge of this disease. This study is an evaluation of the registry and an analysis of its patient population.

METHODS

The registry has a database hosted on the website www.redaat.es. It collects clinical and functional data on patients with PiSZ, ZZ phenotypes and other rare variants.

RESULTS

Thanks to the collaboration of 124 physicians, the registry currently contains information on 511 individuals from 103 healthcare centers. Of these 511, 348 (74.2%) are Pi*ZZ homozygotes, and 100 (19.5%) are Pi*SZ heterozygotes. More cases are seen in tertiary level hospitals. A total of 81% of the cases have respiratory disease, and a lower proportion of AATD cases were detected by family screening or liver disease. Follow-up data are available for 45% of the cases, and 35% received alpha-1 antitripsin replacement therapy.

CONCLUSIONS

The REDAAT registry is a useful tool for obtaining quality information about this minority disease in routine clinical practice conditions, although it is difficult to obtain follow-up data, and the representativeness of the sample included cannot be determined.

Recommendations for aetiological diagnosis of bronchiectasis

The number of bronchiectasis diagnoses has increased in the last two decades due to several factors. Research carried out over the last years showed that an aetiological diagnosis could change the approach and treatment of a relevant percentage of patients and consequently the prognosis. Currently, systematic investigation into aetiology, particularly of those disorders that can be subject to specific treatment, is recommended. Given the complexity of the aetiological diagnosis, the Pulmonology Portuguese Society Bronchiectasis Study Group assembled a working group which prepared a document to guide and standardize the aetiologic investigation based on available literature and its own expertise. The goal is to facilitate the investigation, rationalize resources and improve the delivery of care, quality of life and prognosis of patients with bronchiectasis.

Diagnosis of alpha-1 antitrypsin deficiency: a population-based study

INTRODUCTION

Alpha-1 antitrypsin deficiency (AATD) remains an underdiagnosed condition despite initiatives developed to increase awareness. The objective was to describe the current situation of the diagnosis of AATD in primary care (PC) in Catalonia, Spain.

METHODS

We performed a population-based study with data from the Information System for Development in Research in Primary Care, a population database that contains information of 5.8 million inhabitants (80% of the population of Catalonia). We collected the number of alpha-1 antitrypsin (AAT) determinations performed in the PC in two periods (2007-2008 and 2010-2011) and described the characteristics of the individuals tested.

RESULTS

A total of 12,409 AAT determinations were performed (5,559 in 2007-2008 and 6,850 in 2010-2011), with 10.7% of them in children. As a possible indication for AAT determination, 28.9% adults and 29.4% children had a previous diagnosis of a disease related to AATD; transaminase levels were above normal in 17.7% of children and 47.1% of adults. In total, 663 (5.3%) individuals had intermediate AATD (50-100 mg/dL), 24 (0.2%) individuals had a severe deficiency (<50 mg/dL), with a prevalence of 0.19 cases of severe deficiency per 100 determinations. Nine (41%) of the adults with severe deficiency had a previous diagnosis of COPD/emphysema, and four (16.7%) were diagnosed with COPD within 6 months.

CONCLUSION

The number of AAT determinations in the PC is low in relation to the prevalence of COPD but increased slightly along the study period. The indication to perform the test is not always clear, and patients detected with deficiency are not always referred to a specialist.

Guideline Adherence in Outpatient Clinics for Chronic Obstructive Pulmonary Disease: Results from a Clinical Audit

OBJECTIVES

Previous clinical audits of COPD have provided relevant information about medical intervention in exacerbation admissions. The present study aims to evaluate adherence to current guidelines in COPD through a clinical audit.

METHODS

This is a pilot clinical audit performed in hospital outpatient respiratory clinics in Andalusia, Spain (eight provinces with more than 8 million inhabitants), including 9 centers (20% of the public centers in the area) between 2013 and 2014. Cases with an established diagnosis of COPD based on risk factors, clinical symptoms, and a post-bronchodilator FEV1/FVC ratio of less than 0.70 were deemed eligible. The performance of the outpatient clinics was benchmarked against three guidance documents available at the time of the audit. The appropriateness of the performance was categorized as excellent (>80%), good (60-80%), adequate (40-59%), inadequate (20-39%), and highly inadequate (<20%).

RESULTS

During the audit, 621 clinical records were audited. Adherence to the different guidelines presented a considerable variability among the different participating hospitals, with an excellent or good adherence for symptom recording, MRC or CAT use, smoking status evaluation, spirometry, or bronchodilation therapy. The most outstanding areas for improvement were the use of the BODE index, the monitoring of treatments, the determination of alpha1-antitrypsin, the performance of exercise testing, and vaccination recommendations.

CONCLUSIONS

The present study reflects the situation of clinical care for COPD patients in specialized secondary care outpatient clinics. Adherence to clinical guidelines shows considerable variability in outpatient clinics managing COPD patients, and some aspects of the clinical care can clearly be improved.

Application of a diagnostic algorithm for the rare deficient variant Mmalton of alpha-1-antitrypsin deficiency: a new approach

BACKGROUND AND OBJECTIVES

Alpha-1-antitrypsin deficiency (AATD) is associated with a high risk for the development of early-onset emphysema and liver disease. A large majority of subjects with severe AATD carry the ZZ genotype, which can be easily detected. Another rare pathologic variant, the Mmalton allele, causes a deficiency similar to that of the Z variant, but it is not easily recognizable and its detection seems to be underestimated. Therefore, we have included a rapid allele-specific genotyping assay for the detection of the Mmalton variant in the diagnostic algorithm of AATD used in our laboratory. The objective of this study was to test the usefulness of this new algorithm for Mmalton detection.

MATERIALS AND METHODS

We performed a retrospective revision of all AATD determinations carried out in our laboratory over 2 years using the new diagnostic algorithm. Samples with a phenotype showing one or two M alleles and AAT levels discordant with that phenotype were analyzed using the Mmalton allele-specific genotyping assay.

RESULTS

We detected 49 samples with discordant AAT levels; 44 had the MM and five the MS phenotype. In nine of these samples, a single rare Mmalton variant was detected. During the study period, two family screenings were performed and four additional Mmalton variants were identified.

CONCLUSION

The incorporation of the Mmalton allele-specific genotyping assay in the diagnostic algorithm of AATD resulted in a faster and cheaper method to detect this allele and avoided a significant delay in diagnosis when a sequencing assay was required. This methodology can be adapted to other rare variants. Standardized algorithms are required to obtain conclusive data of the real incidence of rare AAT alleles in each region.

Alpha-1 antitrypsin deficiency caused by a novel mutation (p.Leu263Pro): Pi*ZQ0gaia - Q0gaia allele

Severe alpha-1 antitrypsin deficiency (AATD) is generally associated with PI*ZZ genotype and less often with combinations of PI*Z, PI*S, and other rarer deficiency or null (Q0) alleles. Severe AATD predisposes patients to various diseases, including pulmonary emphysema. Presented here is a case report of a young man with COPD and AATD. The investigation of the AATD showed a novel mutation p.Leu263Pro (c.860T>C), which was named Q0gaia (Pi*ZQ0gaia). Q0gaia is associated with very low or no detectable serum concentrations of AAT.