Simple and specific test for the diagnosis of aspiration into the airways using a corn flour-milk mixture in a hamster model.

Abstract

Aspiration into the airways is one of the major causes of lung disease in infants and young children. Unfortunately, the diagnosis of aspiration is often delayed due to unawareness and low sensitivity and specificity of existing diagnostic tests. We tested the efficacy of a new method, using a mixture of corn flour in milk instilled into the trachea, to diagnose aspiration in a hamster model. Forty-five female hamsters were used for the experiments. Twenty hamsters underwent tracheal instillation of 0.1 ml of a mixture of 7.5% corn flour (containing starch granules with a diameter of 2-30 microm) in milk. Twenty control animals underwent tracheal instillation of saline. Five hamsters served as naive controls. Five animals from the corn flour and saline groups underwent bronchoalveolar lavage on days 1, 3, 7, and 14 after tracheal instillation. Starch granules were identified under light microscopy, using both iodine and Diff-Quik staining in all the corn flour-instilled animals and during all days after tracheal instillation. No starch granules were detected in naive or saline-treated animals. Starch granules were detected over 14 days following tracheal instillation, with a half-life rate of disappearance of about 6 days. Corn flour aspiration in hamsters can be easily identified by light microscopy, using simple laboratory techniques.