Staphylococcus warneri: Skin Commensal and a Rare Cause of Urinary Tract Infection

Coagulase negative Staphylococci often grow in cultures and form one of the most abundant flora among skin microbiome. It is important and challenging to identify and treat clinically significant infections caused by these organisms. Prosthetic devices, catheters and conditions causing immunocompromised states are the risk factors for such infections. We describe a case of clinically significant and symptomatic urinary tract infection (UTI) in a 65-year-old man with liver cirrhosis caused by Staphylococcus warneri which forms <1% of Staphylococcal skin flora. He was treated successfully with fluoroquinolone antibiotic based on culture results. It is important to understand potential of this organism to cause serious infections which warrant culture-directed antibiotic therapy.