Overviews:
The ratio of neutrophils to squamous epithelial cells in a Gram stain can help determine if the specimen is appropriate for culture.
Examination of the Gram stain:
(1) number of neutrophils in 10 low power microscopic fields (10x objective)
(2) number of squamous epithelial cells in 10 low power microscopic fields (10x objective)
(3) presence of mucus threads
ratio of neutrophils to squamous epithelial cells =
= (number of neutrophils) / (number of squamous cells)
Interpretation - a specimen is considered adequate for culture if one of the following:
(1) The ratio is >= 2, OR
(2) There are mucus threads with < 10 cells (assume this is based on the total cell count over the 10 microscopic fields).
If the specimen is not adequate, then a repeat specimen should be collected.
