A 26-year-old man presents with an infected foot from stepping on a nail 2 days ago. The nail penetrated through the sole of his tennis shoe. He sprayed some antiseptic on it and did not seek medical help because he had his last tetanus booster about 1 year ago and he thought that would take care of the wound. The foot is quite inflamed around the wound with a little blue-green pus on the bandage. The organism isolated is a Gram-negative rod that is oxidase positive and does not ferment any carbohydrates. Which organism is most likely?

Question

Quizplus · Accepted Answer

From both the genus description and the epidemiology, it is most likely Pseudomonas aeruginosa. The rubber soles of tennis shoes generally clean off nails as they enter, so it is the flora of the inside of the tennis shoe, frequently Pseudomonas aeruginosa, causing these infections.

A 26-Year-Old Man Presents with an Infected Foot from Stepping