Martina Neuschlová

Deep Nasal Inspirations Increase the Cough Threshold in Children with Mild Asthma

Asthma is a chronic inflammatory disease characterized by bronchospasms accompanied with frequent coughing, the pathogenesis of which is not clear. In healthy adults deep inspirations (DIs) provide a protective effect against bronchoconstriction triggered by methacholine inhalation, which correlates with the number of accompanying cough efforts. The aim was to study the effect of deep nasal inspirations representing the voluntary equivalent of the sniff-like aspiration reflex on the capsaicin-induced cough in children with mild asthma. The cough reflex sensitivity to capsaicin was determined using a compressed air-driven nebulizer in 21 children (8 girls and 13 boys of median age 13.3 year) suffering from mild asthma (FEV(1)∼80%). The effect of five previous DIs through the nose was examined on the elicitability of two and five or more cough efforts (C2, C5). Under control conditions, the concentration of 20.86 (14.58-29.8) μmol/l of capsaicin provoked two cough efforts (C2). After five DIs similar reaction required significantly higher concentrations of capsaicin: 29.02 (18.88-44.6) μmol/l; P=0.016. Five or more cough efforts (C5) were not significantly changed after previous DIs 161.49 (77.31-337.33) μmol/l and without DIs 141.52 (68.77-291); P=0.54. A series of five deep inspirations decreases the cough reflex sensitivity to evoke two efforts (C2) in children with mild asthma. The inhibitory effect of similar DIs disappeared after repeated applications of increasing doses of capsaicin, aiming to evoke five or more cough efforts, suggesting a reflex character of protective effect of DIs.

Identification of Mycobacterium Species by MALDI-TOF Mass Spectrometry

Matrix-assisted laser desorption ionization - time-of-flight (MALDI-TOF) mass spectrometry enables to identify microorganisms by comparison of the protein content with reference spectra in the database. The aim of this study was to evaluate the efficacy of phenotypic identification of mycobacteria by MALDI-TOF mass spectrometry in laboratory practice. Seventy five isolates of mycobacteria were identified by molecular and phenotypic method, and the results were compared by MALDI-TOF. For MALDI-TOF, material was processed according to the Bruker Daltonics protocol and Mycobacterial Library database version 2.0, with 313 reference mycobacteria spectra. All except one of the 72 isolates agreed with regard to the species and genus by both methods. Forty three isolates were identified as the M. tuberculosis complex by MALDI-TOF. Thirty one isolates of nontuberculous mycobacteria were consistently identified by both methods to the species level. We conclude that MALDI-TOF mass spectrometry is an accurate method of bacterial identification. Simplicity, speed, and economic availability of the method makes it suitable for mycobacteria identification in a routine laboratory.

Microbiologic Methods in the Diagnostics of Upper Respiratory Tract Pathogens

Upper respiratory tract infection (URI) is a nonspecific term used to describe acute infections involving the nose, paranasal sinuses, pharynx, and larynx above the vocal cords. The aim of this study was to provide a summary of the most common pathogens of URI and to compare advantages and disadvantages of traditional and new rapid microbiological tests used to identify them. Blood samples were simultaneously examined by the enzyme-linked immunosorbent assay (ELISA) and by the FilmArray Respiratory Panel for eight different pathogens in a total of 15 tests performed in nasopharyngeal swabs. The ELISA method is unable to identify the pathologic agent until the host’s immune system elicits a response. The method is readily available in many laboratories at a low cost, which puts less strain on economic resources. The FilmArray® Panel, on the other hand, is more expensive, but it is fast and exact in the identification of a broad spectrum etiologic agents. Nonetheless, since most repiratory tract infections are viral in origin and there is no treatment available, the diagnosis provided by the FilmArray Panel does not provide any additional clinical benefit and thus should be used only whenever necessary on the individual basis.

COUGH REFLEX SENSITIVITY TESTING IN ASTHMATIC PATIENTS AND HEALTHY VOLUNTEERS

Abstract Asthma and allergic diseases are complex conditions caused by a combination of genetic and environmental factors. Cough is a major symptom in some people with asthma. Cough reflex sensitivity (CRS) test with capsaicin is one of the most important method for cough studying. Cough reflex sensitivity was defined as the lowest concentration of capsaicin that elicited 2 or more (C2) and 5 or more coughs (C5). The aim of this study was to find out a cough reflex sensitivity in patients with asthma bronchiale and in healthy volunteers. In the present study we conclude that cough reflex sensitivity was significantly increased in asthmatic adult patients compared with healthy adult volunteers.