Lesson of the month 2: toxic shock syndrome

Toxic Shock Syndrome: Still a Timely Diagnosis

BACKGROUND

Toxic shock syndrome (TSS) is an acute, severe, toxin-mediated disease, characterized by fever, hypotension, and multiorgan system involvement. Toxic shock syndrome has made headlines because of its high associated morbidity and mortality rate in previously healthy young females. Incidence peaked in the early 1980s owing to increased usage of ultra-absorbent tampons. After improved patient education and tampon labeling, the incidence of menstrual TSS has declined.

CASE

A previously healthy 14-year-old girl presented to an urgent care center with a 2-day history of fever, erythematous maculopapular rash, vomiting, diarrhea, and malaise. She was found to be tachycardic and hypotensive. Investigations revealed thrombocytopenia, an elevated white count and lactate, and acute kidney injury, consistent with septic shock. Recent tampon usage with menstruation was reported, and a pelvic examination revealed purulent vaginal discharge. The patient was transferred to a pediatric intensive care unit for antibiotic and vasopressor therapy. Vaginal swabs later tested positive for Staphylococcus aureus and TSS toxin-1.

CONCLUSIONS

Although the incidence of TSS has decreased in recent years, it is crucial that clinicians rapidly recognize and treat this life-threatening condition. Emergency physicians should always have a high index of suspicion for TSS in young females presenting without another obvious cause of shock. A pelvic examination should always be completed in these cases.

Menstrual toxic shock syndrome: case report and systematic review of the literature

Menstrual toxic shock syndrome (mTSS) is a life-threatening disease caused by superantigen-producing Staphylococcus aureus. Incidence ranges from 0·03 to 0·50 cases per 100 000 people, with overall mortality around 8%. In this Grand Round, we present the case of a previously healthy 23-year-old menstruating woman who was diagnosed with mTSS after she presented at our hospital with a septic condition for the second time. The diagnosis was confirmed by fulfilment of the clinical criteria outlined by the US Centers for Disease Control and Prevention (CDC; fever, rash, desquamation, hypotension, and multi-system involvement) as well as a nasal swab positive for the S aureus strain and presence of the gene encoding for toxic shock syndrome toxin 1 (TSST-1). In the early 1980s, when mTSS was first described, use of tampons was considered the main risk factor. Today, the complex interplay between pathogenic factors of S aureus, immunological mechanisms of the host, and changes in the vaginal ecosystem during menstruation has broadened current understanding of the disease, and the CDC criteria have appreciable limitations in everyday clinical practice.

Toxic shock syndrome: the great masquerader

Toxic shock syndrome is a rare but potentially lethal toxin-mediated illness that can be caused by streptococcal and staphylococcal species. It initially presents as a febrile illness that rapidly progresses to multiorgan dysfunction, hence a high index of suspicion coupled with rapid verification of the diagnosis and aggressive treatment is required to improve the outcome of the disease. A 23-year-old man presented with high-grade fever associated with headache, retro-orbital pain, gastroenteritis and gum bleeds. Treatment was initiated keeping in mind the possibility of dengue haemorrhagic fever. However, further clinical deterioration led us to re-examine our patient, revealing an old neglected wound. Microbiological confirmation of methicillin-resistant Staphylococcus aureus from the wound swab and prompt institution of appropriate treatment led to a favourable outcome in a case known to be associated with serious morbidity and mortality.

A Multiplex Assay for Detection of Staphylococcal and Streptococcal Exotoxins

Staphylococcal and streptococcal exotoxins, also known as superantigens, mediate a range of diseases including toxic shock syndrome, and they exacerbate skin, pulmonary and systemic infections caused by these organisms. When present in food sources they can cause enteric effects commonly known as food poisoning. A rapid, sensitive assay for the toxins would enable testing of clinical samples and improve surveillance of food sources. Here we developed a bead-based, two-color flow cytometry assay using single protein domains of the beta chain of T cell receptors engineered for high-affinity for staphylococcal (SEA, SEB and TSST-1) and streptococcal (SpeA and SpeC) toxins. Site-directed biotinylated forms of these high-affinity agents were used together with commercial, polyclonal, anti-toxin reagents to enable specific and sensitive detection with SD₅₀ values of 400 pg/ml (SEA), 3 pg/ml (SEB), 25 pg/ml (TSST-1), 6 ng/ml (SpeA), and 100 pg/ml (SpeC). These sensitivities were in the range of 4- to 80-fold higher than achieved with standard ELISAs using the same reagents. A multiplex format of the assay showed reduced sensitivity due to higher noise associated with the use of multiple polyclonal agents, but the sensitivities were still well within the range necessary for detection in food sources or for rapid detection of toxins in culture supernatants. For example, the assay specifically detected toxins in supernatants derived from cultures of Staphylococcus aureus. Thus, these reagents can be used for simultaneous detection of the toxins in food sources or culture supernatants of potential pathogenic strains of Staphylococcus aureus and Streptococcus pyogenes.

Staphylococcal toxic shock syndrome caused by tampon use

The authors report a case of near-fatal sepsis with multiorgan failure resulting from a Staphylococcal tampon-associated toxic shock syndrome, requiring a lengthy critical care admission. Successful treatment of this condition focuses on early identification, source control, and administration of antimicrobial agents. Intravenous immunoglobulin therapy used early may prevent widespread tissue necrosis.