Corticosteroid treatment of @entity1 following acid @entity1173 has been reported to increase the incidence of @entity2028 , with @entity794 being a common isolate. We hypothesized that administration of @entity1667 (MP) to @entity19 with acid-injured lungs would impair pulmonary clearance of @entity794 by compromising the bactericidal oxidative metabolism of pulmonary phagocytes. Using an inhalational bacterial challenge, we established that MP decreased pulmonary clearance of @entity794 . In @entity19 with normal lungs and without MP treatment 14 +/- 2% of all initially deposited Staphylococci remained at 4 hr compared to 28 +/- 2% remaining in the lungs of @entity19 with MP treatment. In @entity19 with acid-injured lungs, MP caused a greater impairment of @entity794 clearance at 4 hr with 44 +/- 10% of all initially deposited bacteria remaining in the lungs of control @entity19 and 210 +/- 24% remaining in the lungs of MP-treated @entity19 . After it was demonstrated that there was no difference in the numbers of phagocytic cells obtained by lung lavage from @entity19 with or without MP treatment, the bactericidal oxidative metabolism of these cells was quantitated using @entity6931 -amplified chemiluminescence. Phagocytic cells from @entity19 not exposed to @entity794 displayed minimal chemiluminescence whether they were treated with saline (22 +/- 14 mV) or MP (14 +/- 8 mV). In contrast, phagocytes from saline-treated @entity19 exposed to @entity794 showed a significant increase in chemiluminescence (159 +/- 22 mV). Pretreatment with MP, however, prevented this response to @entity794 (21 +/- 13 mV), indicating that bactericidal oxidative metabolism of these phagocytic cells had been suppressed.(ABSTRACT TRUNCATED AT 250 WORDS)

XXXX impairs the bactericidal activity of alveolar macrophages.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1667 :: ('MESH:D008775', 'Chemical') :: ['methylprednisolone'] @entity19 :: ('10090', 'Species') :: ['mice'] @entity794 :: ('1280', 'Species') :: ['Staphylococcus aureus', 'S. aureus'] @entity6931 :: ('MESH:D008165', 'Chemical') :: ['luminol'] @entity2028 :: ('MESH:D018410', 'Disease') :: ['bacterial pneumonia'] @entity1173 :: ('MESH:D053120', 'Disease') :: ['aspiration']
@entity1667 :: (MESH:D008775,Chemical) :: ['Methylprednisolone']
