title: Histopathologic findings and energy dispersive X-ray spectroscopic analysis of experimentally induced foreign-body pneumonias in rats.
abstract: To document the diagnostic features of foreign-body pneumonias, four commonly used orally administered medicaments were instilled into the lungs of Sprague-Dawley rats. Rats in each group received a single 0.4 ml dose of either barium sulfate suspension (BaSO4), mineral oil, Pepto-bismol, or Kaopectate inoculated into a lung via a mainstem bronchus. The other lung served as a non-inoculated control. Rats were euthanatized on post-inoculation day 2 or 7 in order to document fully-developed acute pulmonary lesions and developing, chronic pulmonary lesions, respectively. Light microscopic features of BaSO4-inoculated lungs were distinctive from changes in mineral oil-inoculated lungs at both post-inoculation days. On post-inoculation day 2, rats inoculated with BaSO4 had pneumonia characterized by large numbers of alveolar macrophages containing green-to-brown granular material. There was minimal interstitial involvement. On post-inoculation day 2, mineral oil caused pneumonia characterized by giant cells and alveolar macrophages that had cytoplasms distended with variably-sized clear vacuoles. Lungs inoculated with BaSO4 or mineral oil had changed little on post-inoculation day 7 compared to the light microscopic features observed on day 2. On post-inoculation day 2, rats inoculated with either Pepto-bismol or Kaopectate had broncho-interstitial pneumonia with areas of necrosis and hemorrhage. On post-inoculation day 7, lungs inoculated with Pepto-bismol or Kaopectate had extensive fibrosis within alveolar lumens. Energy dispersive spectroscopy performed on sections of lung from rats given BaSO4, Pepto-bismol, and Kaopectate yielded a unique elemental spectrum for each compound in situ on post-inoculation days 2 and 7.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Pathology, College of Veterinary Medicine, Michigan State University, East Lansing.
authors.forename: R F
authors.initials: RF
authors.lastname: Slocombe
authors.forename: M G
authors.initials: MG
authors.lastname: Evans
authors.forename: F J
authors.initials: FJ
authors.lastname: Derksen
mesh_terms: D000818:Animals; D001466:Barium Sulfate / Q000633:toxicity; D001729:Bismuth; D004338:Drug Combinations / Q000633:toxicity; D004577:Electron Probe Microanalysis; D005260:Female; D007616:Kaolin / Q000633:toxicity; D008168:Lung / Q000187:drug effects / Q000473:pathology*; D008899:Mineral Oil / Q000633:toxicity; D009942:Organometallic Compounds / Q000633:toxicity; D010368:Pectins / Q000633:toxicity; D011015:Pneumonia, Aspiration / Q000473:pathology*; D051381:Rats; D011919:Rats, Inbred Strains; D012459:Salicylates / Q000633:toxicity
chemical_list: D004338:Drug Combinations; D009942:Organometallic Compounds; D012459:Salicylates; D007616:Kaolin; D001466:Barium Sulfate; C015715:bismuth subsalicylate; D008899:Mineral Oil; C017448:pectin-kaolin combination; D010368:Pectins; D001729:Bismuth