Phagocytosis and oxidative burst of granulocytes in the upper respiratory tract in chronic and acute inflammation.

Acute diseases and chronic conditions may be associated with altered neutrophil functions. The aim of this investigation was to study the number and function of granulocytes in the upper respiratory tract in acute and chronic airway inflammation. The 136 participating subjects were assigned to 6 groups; group 1: controls; group 2: smokers, < 10 cigarettes/day; group 3: smokers, > 10 cigarettes/day; group 4: patients with allergic rhinitis; group 5: patients with obstructive sleep apnea; group 6: patients with acute viral upper respiratory tract infection. Whole blood and nasal lavage fluid were obtained and a cell count was performed. Phagocytosis of opsonized bacteria and the oxidative burst was measured. Total cell counts and absolute number of neutrophils in nasal lavage (NAL), but not in blood, were elevated in all groups compared to controls. Highest increases of neutrophils were observed in group 4 (7-fold) and group 6 (25-fold), p < .01. Phagocytosis and oxidative burst of granulocytes recovered by NAL were found to be increased in group 4 (25% and 15%, respectively) and group 6 (35% and 21%) only, but decreased in the other groups. We conclude that conditions leading to acute or chronic inflammation in the upper respiratory tract are associated with altered functions of granulocytes recovered by NAL but not blood, suggesting local modulating factors. We speculate that chronic inflammation, in contrast to acute conditions, is associated with impaired granulocyte function.