Divergent dynamics of inflammatory mediators and multiplex PCRs during airway infection in cystic fibrosis patients and healthy controls: Serial upper airway sampling by nasal lavage

Abstract

BackgroundIn cystic fibrosis (CF), acute respiratory exacerbations critically enhance pulmonary destruction. Since these mainly occur outside regular appointments, they remain unexplored. We previously elaborated a protocol for home-based upper airway (UAW) sampling obtaining nasal-lavage fluid (NLF), which, in contrast to sputum, does not require immediate processing. The aim of this study was to compare UAW inflammation and pathogen colonization during stable phases and exacerbations in CF patients and healthy controls.MethodsInitially, we obtained NLF by rinsing 10 ml of isotonic saline/nostril during stable phases. During exacerbations, subjects regularly collected NLF at home. CF patients directly submitted one aliquot for microbiological cultures. The remaining samples were immediately frozen until transfer on ice to our clinic, where PCR analyses were performed and interleukin (IL)-1β/IL-6/IL-8, neutrophil elastase (NE), matrix metalloproteinase (MMP)-9, and tissue inhibitor of metalloproteinase (TIMP)-1 were assessed.ResultsAltogether, 49 CF patients and 38 healthy controls (HCs) completed the study, and 214 NLF samples were analyzed. Of the 49 CF patients, 20 were at least intermittently colonized with P. aeruginosa and received azithromycin and/or inhaled antibiotics as standard therapy. At baseline, IL-6 and IL-8 tended to be elevated in CF compared to controls. During infection, inflammatory mediators increased in both cohorts, reaching significance only for IL-6 in controls (p=0.047). Inflammatory responses tended to be higher in controls [1.6-fold (NE) to 4.4-fold (MMP-9)], while in CF, mediators increased only moderately [1.2-1.5-fold (IL-6/IL-8/NE/TIMP-1/MMP-9)]. Patients receiving inhalative antibiotics or azithromycin (n=20 and n=15, respectively) revealed lower levels of IL-1β/IL-6/IL-8 and NE during exacerbation compared to CF patients not receiving those antibiotics. In addition, CF patients receiving azithromycin showed MMP-9 levels significantly lower than CF patients not receiving azithromycin at stable phase and exacerbation. Altogether, rhinoviruses were the most frequently detected virus, detected at least once in n=24 (49.0%) of the 49 included pwCF and in n=26 (68.4%) of the 38 healthy controls over the 13-month duration of the study. Remarkably, during exacerbation, rhinovirus detection rates were significantly higher in the HC group compared to those in CF patients (65.8% vs. 22.4%; p<0.0001).ConclusionNon-invasive and partially home-based UAW sampling opens new windows for the assessment of inflammation and pathogen colonization in the unified airway system.

Detection of cytokines in nasal lavage samples of patients with cystic fibrosis: comparison of two different cytokine detection assays

“…In 95.5% of our patients, IL-17 A, [20]. This study showed values below 400 pg/ml for IL-6, which are on average higher than IL-6 measured in NL [8,18,20].…”

“…Another study by Mulvanny et al used a Milliplex MAP Human High Sensitivity T-Cell Panel and analyzed cytokines in sputum samples in patients with stable chronic obstructive pulmonary disease (COPD) [ 20 ]. This study showed values below 400 pg/ml for IL-6, which are on average higher than IL-6 measured in NL [ 8 , 18 , 20 ].…”

“…(IL-8) and 4.3 pg/ml (IL-1β) [ 8 ]. Similar concentrations were also measured by Mainz et al using Milliplex® in NL samples [ 19 ].…”

“…Alternatively, induced sputum samples, as a noninvasive sample collection method, have gained attention [4,5]. Another noninvasive option for the analysis of cytokines is with nasal lavage samples (NL) [7,8]. The collection of sputum proves to be more difficult, especially after introduction of CFTR modulators into routine therapy; therefore, the collection of NL soon became a very promising and simple method to obtain samples for further analysis.…”

Multiplex PCR for respiratory bacteria in acute care

“…The interpretation of the results achieved using different sampling methods is not yet clear. For instance, the use of new biomarkers is currently being investigated for better recognition of infection [21,22]. Furthermore, our cohort was not only limited to patients with respiratory infection symptoms but also included some with chest pain or poor general condition, which presumably also reduced the proportion of positive results.…”