Growing bacteria in the lab.
The skin and mucous membranes are in constant contact with microscopic organisms and always carry "normal flora". These cause no problems on the skin surface, but once inside the body they may cause infection
Staphylococcus epidermidis (S.epidermidis) makes up between 60 to 95 percent of normal flora. It is present on the skin and mucus membranes, such as the lining of the nose and mouth and on animals.
Significance
Intravenous lines can be a route for infection.
Because it is so prevalent on the skin, it is a major cause of infection for hospital patients, present on surfaces and readily contaminating care equipment.
It presents a major infection risk particularly for patients who have large wounds following surgery or who have intravenous lines, urinary catheters or devices such as shunts, heart valves and joint replacements. Intravenous drug users and premature or low-weight newborns are also at increased risk of infection with S. epidermidis.
Identification
Urinary catheters provide a route of entry for S. epidermidis.
The initial symptoms of infection with S. epidermidis are much the same as any bacterial infection and include: headache, fever, fatigue and loss of appetite. Infection of the lining and valves of the heart (endocarditis) may occur in patients with shunts and artificial heart valves and generalized septicaemia (blood poisoning) is a major complication.
Catheterised patients develop urinary infection, with pain on urination and the formation of pus.
Slime
Slime protects against washing and sanitizing.
S. epidermidis forms layers of slime (bio-film) more than 50 cells thick which enables it to adhere to the materials used in surgical implants and prostheses.
Because it is invisible to the naked eye, the presence of the bacteria may not be recognized until the patient develops symptoms of infection.
Antibiotic Resistance
S. epidermidis is resistant to many antibiotics.
Because S. epidermidis is part of the normal skin flora and is a major cause of hospital-acquired infection, it has developed resistance to commonly used antibiotics. Science Direct reports research showing that 80 percent of S. epidermidis is resistant to commonly used antibiotics and that multi-resistance to antibiotics is common.
The slime or bio-film created by the bacteria provides a protective sheath, impairing both the action of antibiotics and the normal immunological response of the body.
Sucrose
The bio-film produced by S. epidermidis is a polysaccharide matrix composed of a complex mixture of carbohydrates (sugars, starches and cellulose).
PubMed reports research which showed that S. epidermidis grew particularly well in a mixture of complex sugars, including sucrose, enabling a diagnosis in as few as five hours. Conversely, whilst sugars are required to form the matrix, Caroline Massonet concluded that high glucose concentration inhibited this.
Significance
S. epidermidis requires a mixture of complex sugars for survival, but when exposed to high concentrations of one sugar it does not thrive.
Faster identification means faster treatment and reducing the biofilm makes antibiotic therapy more effective. A mixture of 70 percent sucrose and silver nitrate or silver sulphadiazine in povidone iodine can be used externally to cleanse and treat potential areas of biofilm, such as external devices like catheters.
Tags: infection with, cause infection, commonly used, commonly used antibiotics, complex sugars, epidermidis resistant