Toxic shock syndrome: Clinical sciences

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Introduction0:00–0:53

Toxic shock syndrome, or TSS for short, is a rare form of septic shock caused by bacteria like Streptococcus pyogenes or Staphylococcus aureus.
Based on the causative agent, TSS is subdivided into two main types called streptococcal TSS and non-streptococcal TSS. TSS typically results from a skin and soft tissue infection, or a contaminated foreign body, such as retained surgical packing.
At these points, bacteria produce toxins that can reach the bloodstream and spread throughout the body, eventually activating T lymphocytes.
This triggers the release of inflammatory cytokines, causing fever, hypotension, and multiple organ failure. Now, when a patient presents with a chief concern suggesting toxic shock syndrome, the first step is to perform an ABCDE assessment.

ABCDE Assessment0:53–2:40

Patients with toxic shock syndrome are generally unstable, so initiate acute medical management to stabilize the airway, breathing, and circulation.
Admit your patient to the ICU, and initiate continuous vital sign monitoring. Next, obtain IV access and consider placing catheters for invasive hemodynamic monitoring, including an arterial line and a central venous catheter, or CVC.
Patients with toxic shock syndrome often have profound hypotension, so begin IV fluid resuscitation. In some cases, to maintain hemodynamic stability, you may need to add vasopressors, targeting a mean arterial pressure or MAP of 65 millimeters of mercury or above.
Lastly, obtain blood cultures and begin broad-spectrum IV antibiotics. Keep in mind that achieving hemodynamic stability, obtaining blood cultures and starting broad spectrum antibiotics is known as the “1-hour sepsis bundle”, and it should be performed within the first hour of patient presentation.
Now, here’s a clinical pearl! You should obtain a blood lactate level in the first hour to check for organ hypoperfusion.
These levels are then monitored serially to guide hemodynamic resuscitation efforts. If lactate levels are high initially, it suggests organ hypoperfusion and indicates the need for aggressive hemodynamic support.
On the flip side, if lactate levels decline with treatment, that helps determine when hemodynamic support can be withdrawn.Okay, once you stabilize the patient, perform a focused history and physical examination and order labs, including CBC and CMP.

H&P + Labs2:40–4:21

The history typically reveals nonspecific systemic symptoms, such as fever, myalgias, and headache; as well as gastrointestinal symptoms, like nausea, vomiting, and diarrhea.
Additionally, the patient could report a rash over the entire skin. In some cases, history might reveal severe pain at the site of a recent soft tissue infection, or other risk factors for infection, like recent tampon use or surgery.On the flip side, the physical exam typically shows hypotension and macular erythroderma, which is a diffuse reddening of the skin due to widespread inflammation.
Later in the course of the illness, the rash may desquamate, or flake off, so keep in mind that you may or may not see desquamation when the patient initially presents!
Finally, labs may reveal elevated lactate, leukocytosis, low hemoglobin and hematocrit, thrombocytopenia, as well as elevated creatinine and the hepatic transaminases, AST and ALT.Here’s another clinical pearl!
As with all cases of septic shock, it’s important to identify the source of infection in TSS. In many cases, a detailed history and physical examination will reveal the source of the infection.
However, in some situations, you might need imaging to locate the focus of infection, especially if you suspect retained foreign bodies.Now, with these findings, you should suspect toxic shock syndrome, so your next step is to collect cultures from the suspected source of infection!

Microbiology4:21–5:44

Soft tissue infections and retained foreign bodies are the most common cause of TSS, but don’t forget other potential infections, such as pneumonia, pharyngitis, and meningitis!
So depending on the patient's presentation, you may need to send cultures from the throat, sputum, genitourinary tract, a skin lesion or wound, or cerebrospinal fluid.
If the suspected source is a necrotizing soft tissue infection, consult the surgical team to evaluate for an emergent operative exploration, debridement, and wound cultures.
Now here’s another clinical pearl! TSS is a clinical diagnosis, which means that no single finding or test is sufficient for diagnosis.
Instead, you should look at the combination of clinical and laboratory findings in order to diagnose TSS. One easy way to do so is using the Centers for Disease Control and Prevention or CDC’s case definitions for streptococcal toxic shock syndrome and non-streptococcal toxic shock syndrome.
These case definitions were designed for public health surveillance, and not for individual patient diagnosis, but they can be a helpful tool at the bedside because they list the classic features of toxic shock syndrome.

Streptococcal TSS Criteria5:44–6:37

Now, your next step is to assess if your patient meets the criteria for streptococcal TSS. The clinical criteria include hypotension, defined as a systolic blood pressure of less than 90 millimeters of mercury; plus evidence of multiorgan involvement affecting at least two organ systems.
This could include renal insufficiency, coagulopathy, hepatic involvement, acute respiratory distress syndrome, a generalized erythematous macular rash, or soft-tissue necrosis.
And that’s not all! The last criterion requires laboratory isolation of group A streptococcus from blood or tissue culture.
If the patient meets these criteria, you can diagnose streptococcal TSS. Now, if streptococcal TSS criteria are not met, your next step is to assess for non-streptococcal TSS criteriaAlright, lets take a closer look at the criteria for non-steptococcal TSS.The clinical criteria for non-streptococcal TSS include fever, diffuse macular erythroderma, desquamation 1 to 2 weeks following the onset of rash, and hypotension.

Non-streptococcal TSS Criteria6:37–7:50

There should also be evidence of multisystem dysfunction, involving at least three of the following organ systems; these include gastrointestinal, muscular, mucous membrane, renal, hepatic, hematologic, or central nervous system.
Lastly, laboratory criteria for non-streptococcal TSS specify that blood cultures, cerebrospinal fluid cultures, and blood serologies must be negative for other infections.
Cultures might be positive for Staphylococcus aureus, but this is not necessary for diagnosis because even though Staphylococcus aureus is the most common causative pathogen, blood cultures are often negative.
Now, if neither Streptococcal TSS nor non-streptococcal TSS criteria are met, consider alternative diagnoses. However, if non-streptococcal TSS criteria are met, you can diagnose non-streptococcal toxic shock syndrome.

Treatment7:50–9:00

Now, for both streptococcal and non-streptococcal TSS treatment is the same. First, remove the focus of infection, if one has been identified.
This may involve retrieving a retained tampon, removing infected surgical packing, or debriding necrotic tissue. Also make sure to tailor IV antibiotics based on culture and sensitivity data.
In addition, regardless of culture and sensitivity results, always put your patient on either clindamycin or linezolid, since these antimicrobials specifically inhibit bacterial protein synthesis and limit the production of more toxins.
Also, you can consider intravenous immunoglobulin, or IVIG for short, which can help neutralize the extracellular toxins already present in the circulation.
Finally, remember that patients with TSS have multisystem involvement, so continue supportive care for the affected organ systems.
This may include dialysis for patients with renal failure, mechanical ventilation for patients with ARDS, and continued vasopressor support for patients with hemodynamic instability.Alright, as a quick recap… Toxic shock syndrome is a toxin-mediated form of septic shock, most commonly associated with Streptococcus pyogenes or Staphylococcus aureus.

Review9:00–10:11

Suspect TSS in patients presenting with fever, hypotension, and a macular erythematous rash that later desquamates. Patients with TSS are often unstable, and acute management includes early hemodynamic support, collection of blood cultures, and initiation of broad-spectrum antibiotics.
Your history and physical exam should aim to identify the source of infection, but order imaging if needed. Once a potential source of infection is identified, obtain cultures, then use the criteria for streptococcal and non-streptococcal TSS to help confirm the diagnosis.
Management includes removing the source of infection, targeted IV antibiotics based on cultures, including clindamycin or linezolid to halt toxin production, and IVIG to neutralize existing toxins while continuing supportive care to address specific organ system dysfunction.
Toxic shock syndrome: Video, Causes, and Symptoms | Osmosis