Toxic Shock Syndrome: Diagnostic Criteria, Laboratory Workup, and Urgency

Toxic Shock Syndrome (TSS) is a toxin-mediated, life-threatening illness (Staphylococcus aureus TSST-1, Streptococcus pyogenes exotoxins). Diagnosis combines clinical, laboratory, and microbiologic criteria.

CDC Case Definition (≥3 of 5)

1. Fever ≥38.9°C
2. Diffuse macular erythroderma (sunburn-like)
3. Hypotension (SBP ≤90 mmHg)
4. Multisystem involvement (≥3: GI, muscular, mucosal, renal, hepatic, hematologic, CNS)
5. Desquamation (1–2 weeks post-onset)

Laboratory Findings

• CBC: thrombocytopenia, leukocytosis, anemia
• Blood cultures: S. aureus or S. pyogenes (sterile site isolation supports diagnosis)
• Renal/hepatic dysfunction, coagulopathy, elevated CK

Key Point

Early recognition and aggressive resuscitation (fluids, vasopressors, source control, clindamycin + β-lactam) are critical; mortality remains 5–15% despite treatment.