Infections à Staphylococcus saprophyticus

Staphylococcus saprophyticus is a frequent cause of urinary tract infections (UTI) in young sexually active female, accounting for up to 42% of UTIs in this population. The virulence of S. saprophyticus is associated with its capicity to adhere to uroepithelial cells. S. saprophyticus can also cause UTI in male patients of any age. More severe infections have also been reported, including acute pyelonephritis, prostatitis, peritonitis and endocarditis. Clinical features of UTI caused by S. saprophyticus are similar to those of UTI caused by Escherichia coli. However, a negative nitrite test in women aged 15-25 years is presumptive for an UTI caused by S. saprophyticus. Although this microorganism is intrinsically susceptible to many antimicrobial agents, it is resistant to fosfomycin, one of first-line treatment options of uncomplicated UTIs. S. saprophyticus is also less susceptible to β-lactams and fluoroquinolones. In case of suspision of UTI caused by S. saprophyticus (young women, negative nitrite test), it is recommended to treat with nitrofurantoin (5 days) or a fluoroquinolone (3 days).