Microbiome and Exacerbations in Neutrophilic Asthma (AsmaEx)

Fundació Institut de Recerca de l'Hospital de la Santa Creu i Sant Pau

Status: Enrolling

Conditions: Asthma; Exacerbation; Microbiome

Treatments: Diagnostic Test: Induced sputum microbiome; Diagnostic Test: Polymerase Chain Reaction (PCR) for viruses and bacteria in nasal swab

Study type: Observational

Funder types: Other; Industry

Identifiers

NCT04260282

IIBSP-ANE-2020-04

Details and patient eligibility

About

Neutrophilic asthma (NA) is the least known severe asthma phenotype. It is associated with more exacerbations, worse control and impaired lung function. One of its possible etiologies is bronchial infections. The study of bronchial microbiology and its relationship with exacerbations is a new line of research.

Objectives: 1) To analyze bronchial microbiome in patients with AN and non-neutrophilic (ANN), with frequent exacerbations and without exacerbations. 2) To relate the presence of bronchial infections with differences in the microbiome. 3) Correlate the characteristics of the microbiome with other evidence used in exacerbations.

Methods: Prospective study involving 40 non-smoking asthmatics without bronchiectasis (20 with AN and 20 with ANN). Of these, 10 in each group will have frequent exacerbations (>2 rounds of systemic steroids in the last year, of >3 days each) and 10 non- frequent exacerbations. AN will be defined as >65% neutrophils in stable phase sputum. All patients will have two stable visits in which clinical variables, asthma control, lung function and induced sputum samples will be collected (for analysis of bronchial inflammatory cell count and for the study of the microbiome by 16 subunit rRNA). Specific Immunoglobulin A (IgA) for Chlamydia Pneumoniae will be determined. In exacerbations, sputum samples will be collected for culture and nasopharyngeal smears for the study of major respiratory viruses and bacteria by multiple polymerase chain reaction.

Full description

See above

Enrollment: 40 estimated patients

Sex: All

Ages: 18 to 80 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age between 18 -80
• Confirmed diagnose of asthma
• Severe persistent asthma

Exclusion criteria

• Respiratory infection during the previous month
• Other significant lung disease

Trial design

40 participants in 2 patient groups

Neutrophilic asthma

Description:

Patients with asthma diagnosed according to guidelines, with eosinophils \<300/mm3 in blood and \<3% in induced sputum

Treatment:

Diagnostic Test: Polymerase Chain Reaction (PCR) for viruses and bacteria in nasal swab

Diagnostic Test: Induced sputum microbiome

Eosinophilic asthma

Description:

Patients with asthma diagnosed according to guidelines, with eosinophils \>300/mm3 in blood and/or \>3% in induced sputum

Treatment:

Diagnostic Test: Polymerase Chain Reaction (PCR) for viruses and bacteria in nasal swab

Diagnostic Test: Induced sputum microbiome