Staphylococcus saccharolyticus infection: case series with a PRISMA-compliant systemic review.

Background: Staphylococcus saccharolyticusis a rare cause of human infectious disease. The clinical characteristics and treatment of patients withS saccharolyticusinfections remain largely unknown. Objectives: We present the first reported case of empyema due toS saccharolyticus. In addition, a systematic review and pooled analysis of allS saccharolyticuscases were done to summarize the clinical and microbiological characteristics and treatment of this rare pathogen. Methods: A case of empyema caused byS saccharolyticusdiagnosed in study hospital was reported. This case and those identified from PubMed, EMBASE, and Web of Science were analyzed. Results: In total, 8 patients were reviewed. The averages of the white blood cell count, sedimentation rate, and C-reactive protein were 16.8 x 10(9)/L, 72 mm/h, and 176 mg/L, respectively. The average time-to-positivity of the anaerobic cultures was 5 days. TheS saccharolyticuswas resistant to metronidazole, but susceptible to fluoroquinolones, clindamycin, and vancomycin in all the cases with drug sensitivity tests available for these antibiotics. Two of 7 patients showed resistance to all beta-lactams. Both of those patients finally died. Conclusions: S saccharolyticusshould be added to the list of anaerobic microorganisms that are able to cause empyema. A prolonged anaerobic culture is critical to improve the yield of this possibly underestimated pathogen. The time to positive culture ofS saccharolyticusmay not help to distinguish true-positive growth from contaminated growth. Acute or subacute courses and systemic evidence of infection may contribute to judge the clinical significance of positive cultures and avoid unnecessary antibiotic treatment. beta-Lactam agents plus fluoroquinolones or vancomycin/teicoplanin or clindamycin may be appropriate to achieve full coverage of the beta-lactam resistant bacteria.