Toxic shock syndrome laboratory findings
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview:
Laboratory findings consistent with the diagnosis of toxic shock syndrome (TSS) include leukocytosis, anemia and thrombocytopenia.
A positive blood culture is diagnostic for Streptococcal TSS, although in other causes of TSS blood culture doesn't have a high value.
Laboratory Findings
The International Guideline Committee for diagnosis of septic shock recommends obtaining appropriate cultures that may include at least two blood cultures, urine, cerebrospinal fluid, wounds, respiratory secretions, or other body fluid cultures before antimicrobial therapy is initiated. In TSS patients, blood culture for staphylococcus is not diagnostic, although blood culture for streptococcal TSS is highly diagnostic.
Primary General Electrolyte and Biomarker Studies
| Complete blood count (CBC) | leukocytosis with a left shift; anemia; thrombocytopenia with platelets <100 x 10^3/microliter
Hematocrit levels up to 80 percent have been reported |
||
| lood culture | Bacteremia | ||
| Renal function tests | serum BUN and creatinine: elevated | ||
| Urine Analysis (UA): hemoglobinuria | |||
| Liver Function Tests
(alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, bilirubin) |
elevated transaminases and bilirubin | ||
| Serum lactic acid | elevated in severe sepsis and septic shock | ||
| Metabolic tests | hyponatremia, hypokalemia, hypophosphatemia | ||
| Blood gas analysis-Venous blood gas (VBG) and arterial blood gas analysis (ABG) | Hypoxemia may be present as a result of pulmonary edema and pleural effusion | ||
| Creatine phosphokinase (CPK) | Elevated |
- Leukemoid reaction is highly predictive of mortality
due to capillary leak from toxin-mediated changes in the vascular endothelium and a
A diagnosis of probable GAS TSS can be made if GAS is isolated from a normally nonsterile site (eg, throat, vagina, skin lesion) but the patient fulfills the other criteria noted above and no other etiology for the illness is identified.
Recovery of the organism from blood cultures usually takes 8 to 24 hours. Gram stain of involved tissue demonstrating gram-positive cocci in pairs and chains can provide an early diagnostic clue in many cases.....8418347
is common.....
Cultures from mucosal and wound sites should be obtained because S. aureus isolates can be tested for toxin production in research laboratories.acute and convalescent serum can be analyzed for antibody responses to various S. aureus exotoxins. The presence of a strain of S. aureus that produces toxin in a patient who does not have acute phase antibody to the toxin is highly suggestive of TSS.
analysis of peripheral blood T cells from adults with TSS has shown a protracted expansion of TSST-1–reactive Vβ2-positive T cells persisting for 4–5 weeks.
| Blood microscopy and culture (blood, wound, fluid, tissue) | positive for group A streptococcus or Staphylococcus aureus |
| Prothrombin time | prolonged in staphylococcal disease in conjunction with DIC |
| Partial thromboplastin time | prolonged in staphylococcal disease in conjunction with DIC |
| Creatine kinase (CK) | elevated in necrotizing fasciitis or myositis and in some staphylococcal disease |
| Polymerase chain reaction (PCR) | protracted expansion of TSST-1–reactive Vβ2-positive T cells persisting for 4–5 weeks |
| serotyping | evidence of streptococcal exotoxins |