Comparison of methods for the detection of penicillinase-producing Neisseria gonorrhoeae

In an evaluation of four methods for detecting penicillinase-producing Neisseria gonorrhoeae the chromogenic cephalosporin, rapid iodometric, and penicillin disc diffusion methods gave complete agreement for all the 202 strains of gonococci tested. No false-positive or false-negative results occurred. The filter paper iodometric method detected 99% of the penicillinase-producing strains without any false-positive result.