title: Poly-lactic-glycolic acid microspheres: a biodegradable marker for the diagnosis of aspiration in hamsters.
abstract: Aspiration is a major cause of lung disease in infants and young children. As the symptoms and signs of aspiration are not specific, the diagnosis is delayed due to a low index of suspicion and low sensitivity and specificity of the available diagnostic tests. In the present study, we evaluated the utility of microspheres composed of a degradable polymer, polylactic glycolic acid (PLGA), as a marker to diagnose aspiration in hamsters. Thirty hamsters underwent direct tracheal instillation of 0.1 mL of a suspension of PLGA. Eighteen other animals served as controls and underwent tracheal instillation of 0.1 mL of saline. Three animals served as naive controls and had no tracheal instillation. Five animals from the PLGA group and three from the saline group underwent whole-lung lavage (WLL) on days 1, 8, 15, 29, 43, and 58. PLGA microspheres were easily identified under light microscopy inside the alveolar macrophages obtained from WLL in all PLGA-instilled animals during all studied days. The number and size of PLGA microspheres within the alveolar macrophages decreased gradually with time with a 90% rate of disappearance of about 36 d. There was a marked neutrophilic response in lung lavage and a mild peribronchial neutrophil infiltration on the first day after tracheal instillation of PLGA which subsequently disappeared. We conclude that PLGA microspheres are a sensitive and specific marker for aspiration in hamsters. The usefulness of this test in diagnosing aspiration in humans should be further evaluated in clinical studies.
authors.affiliation: Institute of Pulmonology, Hadassah-Hebrew University Medical Center, Jerusalem, 91120, Israel. Chaim@hadassah.org.il
authors.forename: Chaim
authors.initials: C
authors.lastname: Springer
authors.forename: Simon
authors.initials: S
authors.lastname: Benita
authors.forename: Yoav
authors.initials: Y
authors.lastname: Sherman
authors.forename: Neslihan
authors.initials: N
authors.lastname: Gursoy
authors.forename: Dalia
authors.initials: D
authors.lastname: Gilhar
authors.forename: Avraham
authors.initials: A
authors.lastname: Avital
mesh_terms: D000818:Animals; D006224:Cricetinae; D005260:Female; D019344:Lactic Acid / Q000737:chemistry*; D016676:Macrophages, Alveolar / Q000166:cytology; D008647:Mesocricetus; D008863:Microspheres; D009504:Neutrophils / Q000166:cytology; D011015:Pneumonia, Aspiration / Q000175:diagnosis* / Q000473:pathology; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid