A gram negative rod produces large mucoid lactose-fermenting colonies, is indole negative, and is urease positive. Which organism is most likely?
1Escherichia coli
2Salmonella species
3Klebsiella pneumoniae✓ 정답
4Shigella species
해설
Mucoid colonies indicate a prominent capsule and are characteristic of Klebsiella pneumoniae. Indole separates it from Escherichia coli, which is indole positive while Klebsiella is negative. Salmonella and Shigella do not ferment lactose.