Staphylococcus saprophyticus

Staphylococcus saprophyticus
Scientific classification
Kingdom:	Bacteria
Phylum:	Firmicutes
Class:	Cocci
Order:	Bacillales
Family:	Staphylococcaceae
Genus:	Staphylococcus
Species:	S. saprophyticus
Binomial name
Staphylococcus saprophyticus (Fairbrother 1940) Shaw et al. 1951

Staphylococcus saprophyticus is a coagulase-negative species of Staphylococcus bacteria. S. saprophyticus is often implicated in urinary tract infections. S. saprophyticus is resistant to the antibiotic novobiocin, a characteristic that is used in laboratory identification to distinguish it from S. epidermidis, which is also coagulase-negative but novobiocin-sensitive.

It is implicated in 10-20% of urinary tract infections (UTI). In females between the ages of ca. 17-27 it is the second-most-common cause of UTIs. It is referred to as "honeymooner's" UTI due to its association with intercourse. It may also reside in the urinary tract and bladder of sexually active females. S. saprophyticus is phosphatase-negative, urease- and lipase-positive. Two subspecies for saprophyticus exist: S. saprophyticus subsp. bovis and S. saprophyticus subsp. saprophyticus, the latter more commonly found in human UTIs. S. Saprophyticus subsp. saprophyticus is distinguished by its being nitrate negative and pyrrolidonyl arylamidase negative while S. Saprophyticus subsp. bovis is nitrate negative and pyrolidonyl arymamidase negative.

Some of the symptoms of this bacteria are burning sensation when passing urine, the urge to urinate more often than usual, the 'dripping effect' after urination, weak bladder, bloated feeling with sharp razor pains in the lower abdomen around the bladder and ovary areas, and razor-like pains during sexual intercourse.

Background

Until the last decade, coagulase-negative staphylococci occurring in urine specimens were usually regarded as a contaminant. In the early 1970s, more than ten years after the original demonstration of Staphylococcus saprophyticus in urine specimens, this species became recognized as a frequent cause of urinary tract infections (UTI). In young women, S. saprophyticus is, after Escherichia coli, the most frequent causative agent of acute UTI. Patients with UTI caused by S. saprophyticus usually present with symptomatic cystitis. Signs and symptoms of renal involvement are also often registered. The urine sediment of a patient with UTI caused by S. saprophyticus has a characteristic appearance under the microscope. Chemical screening methods for bacteriuria do not always succeed in diagnosing UTI caused by S. saprophyticus. Even when such an infection occurs above the neck of the bladder, low numbers of colony-forming units (less than 10(5) cfu/ml) of S. saprophyticus are comparatively often found in the bladder and voided urine. S. saprophyticus is usually susceptible to antibiotics commonly prescribed for patients with UTI, with the exception of nalidixic acid. The bacterium has a capacity for selective adherence to human urothelium. It causes direct hemagglutination. The adhesin for S. saprophyticus is a lactosamine structure. This staphylococcal species produces an extracellular enzyme complex that can inhibit growth of both gram-positive and gram-negative bacteria. Quinolones are commonly used in treatment of S. saprophyticus urinary tract infections.