Toxic shock 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.
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.
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.
In the late 1980s a disease that showed similar signs and symptoms to toxic shock syndrome but was caused by toxins released by toxin-producing 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?
The majority of menstrual toxic shock syndrome cases is associated with the wearing of 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 30-40%.
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.
How do you get toxic shock syndrome and STSS?
Toxic shock syndrome starts from a localised staphylococcal infection which produces the causative exotoxins. 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 whom have not developed antibodies against Staphylococcus aureus may develop toxic shock syndrome. In addition, toxic shock syndrome may occur as a complication of other localised or systemic infections such as pneumonia, osteomyelitis, sinusitis, and skin wounds (surgical or burns), where Staphylococcus aureus infections may develop. In these situations the patient has increased susceptibility to developing toxic shock syndrome.
STSS most often starts from a streptococcal soft-tissue infection such as bacterial cellulitis. Other predisposing factors are if the patient has recently had influenza A infection or chickenpox.
What are the signs and symptoms of toxic shock syndrome and STSS?
Toxic shock syndrome and STSS share similar signs and symptoms. Fever, 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:
- blood cultures
- blood tests
- urine tests
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. Treatment requires hospitalisation and intravenous antibiotics active against the causative organisms are given to eradicate the focus of the infection. 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
- deep surgical cleaning of an infected wound
- oxygen and mechanical ventilation to assist with breathing
How to prevent toxic shock syndrome and STSS
Women who have had toxic shock syndrome should avoid using tampons during menstruation as reinfection may occur. 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.
On DermNet NZ:
- Centres for Disease Control and Prevention (CDC): clinical criteria for toxic shock syndrome and STSS.
- Toxic shock syndrome – Medscape Reference
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