Investigations

Several investigations may confirm the diagnosis of tetanus:

Serum tetanus toxin should be sent prior to administration of immunoglobulin but treatment should never be delayed waiting for the lab result.

• • A positive result confirms the diagnosis
  • A negative result does not exclude it

The most sensitive test involves detection of C. tetani by PCR and culture in samples of debrided tissue. This can also be useful as debridement has an additional therapeutic benefit.

Wound swabs can be sent however a positive result is rare. Low or undetectable serum antibody levels can support the diagnosis of tetanus. [9]