Toxic shock syndrome and toxic shock-like syndrome
What is toxic shock syndrome?
Toxic shock syndrome is an uncommon but severe acute illness with fever, widespread red rash accompanied by involvement of other body organs. Toxic shock syndrome is a medical emergency that requires prompt treatment, as it can result in the failure of vital organs, such as the liver, lungs or heart.
Toxic shock syndrome featured in general public news in the early 1980s when an epidemic occurred. It was linked to the prolonged use of highly absorbent tampons in menstruating women. Since then manufacturers have made changes to tampon production and the number of cases of tampon-induced toxic shock syndrome has dropped significantly. Other causes for toxic shock syndrome include the use of contraceptive diaphragms and vaginal sponges (by women), as well as wound infections.
What causes toxic shock syndrome?
Toxic shock syndrome is caused by the release of exotoxins from toxigenic strains of the bacteria Staphylococcus aureus and Streptococcus pyogenes in a person that lacks anti-toxin antibodies. These exotoxins act as superantigens.
Toxin-producing strains of Staphylococcus aureus causing toxic shock syndrome was first formally described in 1978. Prior to this time the syndrome was known as staphylococcal scarlet fever. Both menstrual and non-menstrual forms of toxic shock syndrome are caused by these toxins, which release massive amounts of cytokines (cell-mediator chemicals) that produce fever, rash, low blood pressure, tissue injury and shock. Strains of Staphylococcus aureus, producing toxic shock syndrome toxin-1 (TSST-1), cause almost all of the cases of menstrual toxic shock syndrome. Non-menstrual toxic shock syndrome are caused by strains producing either TSST-1 or staphylococcal enterotoxin B or C.
What is toxic shock-like syndrome?
In the late 1980s a disease that showed similar signs and symptoms to toxic shock syndrome but was caused by exotoxins released by toxin-producing M-protein strains of Streptococcus pyogenes, was discovered. This disease although sometimes also referred to as toxic shock syndrome is more correctly known as streptococcal toxic shock-like syndrome (STSS) or toxic strep.
Who is at risk of toxic shock syndrome and STSS?
Toxic shock syndrome is associated with menstrual tampons, however the condition is now relatively rare, as most adults have developed protective antibodies to the exotoxin TSST-1. Women who have had toxic shock syndrome are at greatest risk, as the recurrence rate is reported to be between 30–0%.
Non-menstrual toxic shock syndrome and STSS occur in males and females of all age groups and are usually associated with localised or systemic infections. Strangely enough, it has been found that the majority of cases are in healthy persons aged between 20 to 50 years, despite the fact that those most susceptible to staphylococcal and streptococcal infections are infants and young children, elderly, and immunocompromised individuals.
Other risk factors include:
- Recent childbirth, miscarriage or abortion. and the use of birth control devices such as the diaphragm or contraceptive sponges.
- Foreign bodies, including nasal packing to stop nosebleeds and wound packing after surgery.
- Wound infection after surgery
How do you get toxic shock syndrome and STSS?
About 15–40% of healthy humans are carriers of Staphylococcus aureus, that is, they have the bacteria on their skin without any signs of infection or disease (colonisation).However, individuals that have not developed antibodies against Staphylococcus aureus may develop toxic shock syndrome.
Toxic shock syndrome starts from a localised staphylococcal infection which produces the causative exotoxins.
When tampons are used, bacteria can gain entery into the uterus via the cervix. They can also cause cuts in the vagina and permit access of bacteria into the tissues.
Toxic shock syndrome may occur as a complication of other localised or systemic infections such as pneumonia, osteomyelitis, sinusitis, and skin wounds (surgical, traumatic or burns).
STSS usually develops from a streptococcal soft-tissue infection such as bacterial cellulitis, necrotising fasciitis or pyomyositis. Recent influenza A infection or chickenpox may predispose to streptococcal infection.
What are the signs and symptoms of toxic shock syndrome and STSS?
Toxic shock syndrome and STSS share similar signs and symptoms.
- Fever, diffuse rash, low blood pressure, and multiple organ involvement are seen as the hallmarks of these diseases.
- Shedding of the skin in large sheets, especially of the palms and soles, is usually seen 1–2 weeks after the onset of illness.
- Individuals may experience symptoms and signs differently.
Centres for Disease Control and Prevention (CDC) have clinical criteria for toxic shock syndrome and STSS.
|CDC Criteria for toxic shock syndrome and STSS|
|CDC case definition for toxic shock syndrome requires presence of the following 5 clinical criteria:
||CDC case definition for STSS requires isolation of group A streptococci and hypotension with 2 or more of the following clinical criteria:
How are toxic shock syndrome and STSS diagnosed?
In addition to meeting CDC criteria for toxic shock syndrome and STSS, other diagnostic tests may include:
- bacterial swabs from infected site of origin
- blood cultures
- blood tests: CBC, renal and liver function, creatine kinase, coagulation
- urine tests: urinalysis
Toxic shock syndrome diagnosis is confirmed if all 5 CDC clinical criteria are fulfilled. A probable case fulfils 4 of the 5 criteria.
What is the treatment of toxic shock syndrome and STSS?
Management of toxic shock syndrome and STSS is similar.
The treatment starts with:
- Removing the source of infection ie tampons, vaginal sponges, or nasal packing
- Draining and cleaning the site of wound.
Treatment requires hospitalisation and intravenous antibiotics active against the causative organisms are given to eradicate the focus of the infection.
Flucloxacillin, nafcillin, oxacillin, linezolid and first generation cephalosporin are the usual choices. Vancomycin can be used as first line and in patients sensitive to pencillin.
Otherwise, treatment is largely supportive and may include:
- Intravenous fluids to treat shock and prevent organ damage
- Cardiac medications for patients with very low blood pressure
- Dialysis in patients who develop renal failure
- Administration of blood products
- Infusions of intravenous immunoglobulin in severe resistant cases
- Oxygen and mechanical ventilation to assist with breathing
How to prevent toxic shock syndrome and streptococcal toxic shock-like syndrome
Women who have had toxic shock syndrome should avoid using tampons during menstruation as reinfection may occur. If worn, they should be changed ever 4–8 hours. The use of diaphragms and vaginal sponges may also increase the risk of toxic shock syndrome.
Prompt and thorough wound care will help to avoid toxic shock syndrome and STSS.
What is the prognosis of toxic shock syndrome and STSS?
Early diagnosis and appropriate treatment prevents progression of the disease and possible complications such as heart problems, acute renal failure, adult respiratory distress syndrome and disseminated intravascular coagulation.
The mortality rate of toxic shock syndrome is approximately 5–15%, and recurrences have been reported in as many as 30–40% of cases. Mortality rates of STSS are more than 5 times higher than in toxic shock syndrome.