Snapshot A 19-year-old woman presents to the emergency department for worsening myalgias, chills, nausea, and generalized weakness. Her symptoms began approximately 5 days ago. She denies any recent travel history or sick contacts and states she is currently menstruating and using tampons. Her temperature is 102.0°F (38.9°C), blood pressure is 88/55 mmHg, and pulse is 115/min. Physical examination is remarkable for confusion and widespread macular blanching erythroderma that appears like a sunburn. Laboratory studies are significant for a leukocyte count of 17,000/mm3 with a neutrophilic predominance. Blood and urine cultures are obtained. She is admitted to the medical intensive care unit and is receiving aggressive fluid resuscitation and intravenous vancomycin and clindamycin. (Toxic shock syndrome caused by Staphylococcus aureus) Introduction Definition a toxin-mediated and life-threatening illness that results in hypotension and multiorgan failure Epidemiology Incidence staphylococcal toxic shock syndrome is more common in women due to tampon use typically occurs within 5 days of onset of menses in women using tampons Etiology Pathophysiology TSST-1 (in Staphylococcus aureus) or erythrogenic exotoxin A (in Streptococcus pyogenes) cross-links the β region of the T-cell receptor to MHC class II on the antigen presenting cell outside the antigen binding site this cross-linking creates a superantigen, which leads to an overwhelming release of IL-1 IL-2 IFN-γ TNF-β Staphylococcus aureus Group A Streptococcus (Streptococcus pyogenes) Presentation Symptoms confusion chills myalgias nausea vomiting Physical exam fever ≥ 102.0°F (38.9°C) hypotension (systolic blood pressure ≤ 90 mmHg) localized swelling and erythema rash diffuse macular erythroderma (in staphylococcal cases) necrotizing soft tissue infection (in group A strep cases) Studies Labs complete blood count a leukocytosis with left shift can be seen basic metabolic panel useful looking at creatinine to see if there is renal involvement liver function tests may see elevated transaminases and coagulopathy creatinine kinase may be elevated in myositis or necrotizing fasciitis blood cultures and Gram stain arterial blood gas metabolic acidosis (anaerobic metabolism) with respiratory compensation (low pCO2) Differential Other causes of sepsis pneumonia differentiating factors patients will have a productive cough with supportive chest imaging findings (e.g., lobar involvement) urinary tract infection differentiating factor patients will likely have dysuria and urinalysis demonstrating pyuria and urine culture growing an organism meningitis differentiating factor patients may have a headache with neck stiffness Treatment Initial remove the foreign body and control the source of infection Conservative aggressive volume resuscitation indication to improve hypotension Medical empiric antibiotics indication to address the underlying organism regimen clindamycin - preferred first for toxin suppression penicillin G and clindamycin (in Streptococcus pyogenes) vancomycin (or linezolid) and clindamycin (in Staphylococcus aureus) comments it is important to narrow your antibiotics once sensitivity testing returns if Staphylococcus aureus is susceptible to nafcillin, then discontinue vancomycin and treat with nafcillin Complications Multiorgan failure (e.g., renal dysfunction and central nervous system involvement