Identification of attached bacteria in the nasopharynx of the child.

Bacteria attached to epithelial cells in mucus and cell scrapings obtained from the nasopharynx in children undergoing adenoidectomy appear rather monomorphic under the microscope, and for this reason it is not possible to identify different species. To overcome this difficulty, a micromanipulation method has been devised which allows the isolation of single squamous epithelial cells seen to carry bacteria. The cells are transferred to culture media for bacteriological analysis. Ciliated epithelial cells were never seen to carry bacteria, and cultures or these cells gave no growth. Bacterial growth was found in 36 of 47 cultures of single epithelial cells seen to carry 10 to 50 bacteria. Two species were isolated from 11 cultures and three species from one culture. Viridans streptococci dominated; the most frequently isolated species was Streptococcus mitior, followed by Streptococcus group K. In all, 15 different species were found to adhere to squamous epithelial cells in the nasopharynx.