Fig. 2

Airway surface liquid pH and inflammatory markers in bronchoalveolar lavage fluid (BALF). a No relationship between airway surface liquid pH and total cell count in children with CF (n = 29; p = 0.83). However, a significant inverse relationship between airway surface liquid pH and total cell count was observed in the non-CF group (n = 16; p = 0.01). b No relationship between airway surface liquid pH and neutrophil count for children with (n = 24; p = 0.53) or without CF (n = 16; p = 0.83). c A significant relationship between airway surface liquid pH and macrophage count was demonstrated in the non-CF group (n = 16; p = 0.04) but was not observed in the CF group (n = 24; p = 0.18). d There was no correlation between interleukin-8 (IL-8) levels and airway surface liquid pH for the CF (n = 29; p = 0.90) or the non-CF group (n = 16; p = 0.43). For all panels, BALF analysed for inflammatory markers was sampled from the lung lobe corresponding to the airway surface liquid pH measurement. A single pH value was obtained for each individual patient while a single aliquot of BALF was used to measure inflammatory markers. Spearman’s rank correlation test was used for all statistical analyses