HOME

TheInfoList



OR:

''Staphylococcus saprophyticus'' is a
Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain is ...
coccus belonging to the genus ''
Staphylococcus ''Staphylococcus'', from Ancient Greek σταφυλή (''staphulḗ''), meaning "bunch of grapes", and (''kókkos''), meaning "kernel" or " Kermes", is a genus of Gram-positive bacteria in the family Staphylococcaceae from the order Bacillale ...
''. ''S. saprophyticus'' is a common cause of community-acquired
urinary tract infection A urinary tract infection (UTI) is an infection that affects a part of the urinary tract. Lower urinary tract infections may involve the bladder (cystitis) or urethra (urethritis) while upper urinary tract infections affect the kidney (pyel ...
s.


History

''Staphylococcus saprophyticus'' was not recognized as a cause of urinary tract infections until the early 1970s, more than 10 years after its original demonstration in urine specimens. Prior to this, the presence of
coagulase Coagulase is a protein enzyme produced by several microorganisms that enables the conversion of fibrinogen to fibrin. In the laboratory, it is used to distinguish between different types of ''Staphylococcus'' isolates. Importantly, '' S. aureus' ...
-negative staphylococci (CoNS) in urine specimens was dismissed as contamination.


Epidemiology and pathogenesis

In humans, ''S. saprophyticus'' is found in the normal flora of the female genital tract and
perineum The perineum (: perineums or perinea) in placentalia, placental mammals is the space between the anus and the genitals. The human perineum is between the anus and scrotum in the male or between the anus and vulva in the female. The perineum is ...
. It has been isolated from other sources, too, including meat and cheese products, vegetables, the environment, and
human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...
and
animal Animals are multicellular, eukaryotic organisms in the Biology, biological Kingdom (biology), kingdom Animalia (). With few exceptions, animals heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, ...
gastrointestinal tracts. ''S. saprophyticus'' causes 10–20% of
urinary tract infection A urinary tract infection (UTI) is an infection that affects a part of the urinary tract. Lower urinary tract infections may involve the bladder (cystitis) or urethra (urethritis) while upper urinary tract infections affect the kidney (pyel ...
s (UTIs). In females 17–27 years old, it is the second-most common cause of community-acquired UTIs, after ''
Escherichia coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly fo ...
''. Sexual activity increases the risk of ''S. saprophyticus'' UTIs because bacteria are displaced from the normal flora of the vagina and perineum into the
urethra The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which Placentalia, placental mammals Urination, urinate and Ejaculation, ejaculate. The external urethral sphincter is a striated ...
. Most cases occur within 24 hours of sex, earning this infection the nickname "honeymoon cystitis". ''S. saprophyticus'' has the capacity to selectively adhere to human urothelium. The adhesin for ''S. saprophyticus'' is a lactosamine structure. ''S. saprophyticus'' produces no exotoxins.


Clinical features

Patients with urinary tract infections caused by ''S. saprophyticus'' usually present with symptomatic
cystitis A urinary tract infection (UTI) is an infection that affects a part of the urinary tract. Lower urinary tract infections may involve the bladder (cystitis) or urethra ( urethritis) while upper urinary tract infections affect the kidney (py ...
. Symptoms include a burning sensation when passing urine, the urge to urinate more often than usual, a 'dripping effect' after urination, weak bladder, a bloated feeling with sharp razor pains in the lower abdomen around the bladder and ovary areas, and razor-like pains during sexual intercourse. Flank pain may occur due to infection of the upper urinary tract, such as pyelonephritis. Signs and symptoms of renal involvement are also often registered.


Laboratory diagnosis

The urine sediment of a patient with a ''S. saprophyticus'' urinary tract infection has a characteristic appearance under the microscope manifesting leukocytes, erythrocytes, and clumping due to cocci adhering to cellular elements. Chemical screening methods for bacteriuria, such as, urine nitrate and glucose do not always detect ''S. saprophyticus'' infection. This is because unlike
Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists ...
Enterobacteriaceae Enterobacteriaceae is a large family (biology), family of Gram-negative bacteria. It includes over 30 genera and more than 100 species. Its classification above the level of Family (taxonomy), family is still a subject of debate, but one class ...
urinary tract infections, ''S. saprophyticus'' does not reduce nitrate and has a longer generation time, thus does not consume glucose as rapidly. Even when such an infection occurs above the neck of the bladder, low numbers of colony-forming units (less than 105 cfu/ml) are often present. ''Staphylococcus saprophyticus'' is identified as belonging to the genus ''Staphylococcus'' using the
Gram stain Gram stain (Gram staining or Gram's method), is a method of staining used to classify bacterial species into two large groups: gram-positive bacteria and gram-negative bacteria. It may also be used to diagnose a fungal infection. The name comes ...
and catalase test. It is identitified as a species of coagulase-negative staphylococci (CoNS) using the coagulase test. Lastly, ''S. saprophyticus'' is differentiated from '' S. epidermidis'', another species of pathogenic CoNS, by testing for susceptibility to the antibiotic
novobiocin Novobiocin, also known as albamycin, is an aminocoumarin antibiotic that is produced by the actinomycete ''Streptomyces niveus'', which has recently been identified as a subjective synonym for ''S. spheroides'' a member of the class Actinomycet ...
. ''S. saprophyticus'' is novobiocin-resistant, whereas ''S. epidermidis'' is novobiocin-sensitive.


Treatment

''Staphylococcus saprophyticus'' urinary tract infections are usually treated with trimethoprim-sulfamethoxazole or with a quinolone such as to be alone
norfloxacin Norfloxacin, sold under the brand name Noroxin among others, is an antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteri ...
. It has also been shown to be susceptible to ampicillin & ceftriaxone. The many home remedies or natural treatments for urinary tract infections are not clinically proven, such as cranberry juice, alkalinization, and many types of common herbs and spices. Some show promise, such as to affect the formation of
biofilm A biofilm is a Syntrophy, syntrophic Microbial consortium, community of microorganisms in which cell (biology), cells cell adhesion, stick to each other and often also to a surface. These adherent cells become embedded within a slimy ext ...
s on surfaces or medical equipment, and in other ''
in vitro ''In vitro'' (meaning ''in glass'', or ''in the glass'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...
'' situations.


Different subspecies

Two subspecies of ''S. saprophyticus exist'': ''S. s. bovis'' and ''S. s. saprophyticus'', the latter has colony diameter of > 5mm, and more commonly found in human UTIs. ''S. s. saprophyticus'' is nitrate-reductase negative and pyrrolidonyl-arylamidase negative, while ''S. saprophyticus bovis'' has colony diameter of < 5mm, nitrate-reductase positive and pyrolidonyl-arylamidase positive.


References


External links


Type strain of ''Staphylococcus saprophyticus'' at Bac''Dive'' - the Bacterial Diversity Metadatabase
{{Taxonbar, from=Q1708986 saprophyticus Gram-positive bacteria Bacteria described in 1940