A microbiologist is reading stool culture plates.She sees an organism that has a dry, pink colony with a surrounding "halo" of pink on MacConkey (MAC).What is a good presumptive identification of this organism?
A)Enteric pathogen
B)Escherichia/Citrobacter-like organism
C)Klebsiella/Enterobacter-like organism
D)Haemophilus influenzae

Question

Quizplus · Accepted Answer

Escherichia/Citrobacter-like organisms produce a dry, pink colony with a surrounding "halo" of pink.Enteric pathogens are nonlactose fermenters, so they would not produce a pink colony.H.influenzae is fastidious and does not grow on MAC.Klebsiella/Enterobacter-like organisms produce large, mucoid, pink colonies that occasionally have cream-colored centers.

A Microbiologist Is Reading Stool Culture Plates