Detection of Aspergillus Fumigatus and Sensitization in COPD Patients With Bronchiectasis vs Without Bronchiectasis

Wim Janssens100 enrolled

Overview

A single center case-control study with 100 COPD patients will be organized to compare patients with and without bronchiectasis with regard to the presence of Aspergillus in sputum samples, Aspergillus sensitization and vitamin D. Induced sputum samples will be optimized for culture, Aspergillus galatomannan analysis and RT-PCR. This study is part of a larger project in which we assume that chronic respiratory infection by Aspergillus fumigatus and the accompanying immune response play an important role in the development of bronchiectasis in COPD. We suspect that this mechanism is controlled by vitamin D and it fails by suppression of the vitamin D receptor by Aspergillus fumigatus. The present study is designed by the Laboratory of pneumology and will be conducted in collaboration with the Laboratory of clinical bacteriology and mycology of the Catholic University of Leuven.

Study Type

OBSERVATIONAL

Enrollment

100

Conditions

Chronic Obstructive Pulmonary Disease

Interventions

Sputum inductionPROCEDURE

Patients will have to puff 200µg of salbutamol (metered-dose inhaler with spacer device). After 10 minutes FEV1 will be measured with MIR spirobank. If FEV1 is \>= 30% we can safely proceed with sputum induction. An ultrasonic nebulizer will be used to induce sputum. 4% sodiumchloride will be inhaled. Induction will be performed at 5-min intervals until a sample of good quality is obtained. Sodiumchloride of 5% will be used if no good sample is obtained after two intervals with the 4% solution. Maximal time of induction will be 20 minutes. Subjects will spit saliva into one container and rinse the mouth thoroughly with water before coughing sputum into another sterile container. Samples will be refrigerated at 4°C and processed within 24 hours of collection.

Skin prick testPROCEDURE

Skin Prick Test is a reliable method to diagnose IgE-mediated allergic disease. It is minimally invasive and results are immediately available. Interpretation utilizes the presence and degree of cutaneous reactivity as a surrogate marker for sensitization. A positive control, a negative control and Aspergillus fumigatus will be tested. Location will be Protocol version 1 3/11/2014 marked on the volar aspect of the forearm and drops of each solution will be placed (\>= 2cm between drops). A single-head metal lancet will be pressed through the drop of allergen extract and held against the skin for at least 1 second. A new lancet will be utilized for each drop. A wheal diameter of \>= 3mm is a positive result.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Established diagnosis of COPD by medical doctor (based on clinical history or pulmonary function test) * Smoking history of at least 10 pack-years * CT Thorax available for assessment of bronchiectasis * FEV1 \>= 30% Exclusion Criteria: * Mechanical or non-invasive ventilation * Other main respiratory diagnosis other than COPD * Active mycobacterial disease * Immunosuppression other than steroids * Active cancer treatment

Outcomes

Primary Outcomes

Bronchiectasis

Time frame: immediate

Secondary Outcomes

Vitamin D

Time frame: immediate

Prevalence of Aspergillus sensitization

Time frame: max 12weeks

Prevalence of Aspergillus isolation in sputum