Clinical Impact of Bacteremia Due to Staphylococcus saprophyticus

Objective: This was a retrospective study to evaluate the clinical impact of bacteremia due to Staphylococcus saprophyticus and identify which factors influence it. Methods: We reviewed all patients with bacteremia due to S. saprophyticus over the last 12 years. This study was performed at Jichi Medical University Hospital in Japan, a key hospital in the northern Kanto area including Tochigi, Gunma, Ibagagi, and northern Saitama prefectures. We retrospectively reviewed the blood culture results and medical records of all patients with a history of visits or hospitalizations between April 2008 and September 2020. Results: During the study period, 4 blood culture specimens were considered to have S. saprophyticus bacteremia. Two of these were from subjects > 60 years old who had severe infection. A third case, 27 years old, was thought to have a catheter-related bloodstream infection; however, the only symptom was fever, which was not serious. The fourth case, a previously unreported pediatric patient, had non-severe fever. The mean time for a diagnosis of bacteremia by blood culture testing was 42 hours, whereas contamination appeared in cultures after another 50 hours. Conclusion: The pathogenicity of S. saprophyticus might be lower in the blood than in the urine due to its physiological function and activity. In older adults with underlying diseases, the severity of bacteremia was more pronounced, whereas in a young adult and a child, the disease was relatively mild. Age and underlying disease might be useful factors to consider when diagnosing bacteremia due to S. saprophyticus.