A 20-year-old woman goes to her physician complaining of burning upon urination, frequency, and general malaise. Her physician orders a urine culture, which grew 25,000 colony-forming units (CFU)/mL of a catalase-positive, coagulase-negative, novobiocin-resistant gram-positive coccus. What is the most likely pathogen?

Question

Quizplus · Accepted Answer

The symptoms and the urine culture suggest a urinary tract infection (UTI). The most common pathogen causing UTI in sexually active women is Staphylococcus saprophyticus. It is catalase-positive, coagulase-negative, and novobiocin-resistant, which matches the characteristics of the pathogen found in the urine culture. Choices A, B, and C are also coagulase-negative staphylococci, but they are not commonly associated with UTIs.

A 20-Year-Old Woman Goes to Her Physician Complaining of Burning