Selective procedure to isolate haemophilus influenzae from sputa with large quantities of Pseudomonas aeruginosa.

The identification of respiratory pathogens (e. g. Haemophilus influenzae, Streptococcus pneumoniae) is impaired by the presence of large quantities of Pseudomonas aeruginosa, as is the case in the sputum specimens of cystic fibrosis patients. A procedure has been evaluated whereby the selective inhibition of the proliferation of P. aeruginosa is achieved by a broad spectrum pyocin, whereas the growth of H. influenzae is not influenced. This technique has been tested over a two year period resulting in a significantly augmented rate of identification of H. influenzae.