Does a person with systemic lupus erythematosus (SLE) who was scratched by a cat require a tetanus vaccine?

Tetanus Prophylaxis for Cat Scratches in Lupus Patients

Yes, a person with lupus who was scratched by a cat should receive tetanus prophylaxis following the same guidelines as the general population, with the timing based on their last tetanus vaccination—if it has been ≥5 years since their last dose, they need a tetanus-containing vaccine (preferably Tdap if not previously received). 1, 2

Wound Classification and Risk Assessment

• Cat scratches are classified as "other wounds" (non-clean, contaminated wounds) rather than clean wounds, similar to puncture wounds, because cats are coprophagic animals whose claws may be contaminated with dirt, feces, soil, or saliva 2
• While no recent cases of tetanus from cat scratches have been specifically reported, the contaminated nature of these wounds warrants appropriate tetanus prophylaxis 2
• The severity and location of the wound do not reliably predict tetanus risk—tetanus can occur after minor, seemingly innocuous injuries 3

Tetanus Prophylaxis Algorithm Based on Vaccination History

If Last Tetanus Vaccine Was <5 Years Ago:

• No tetanus vaccine or tetanus immunoglobulin (TIG) is needed 2

If Last Tetanus Vaccine Was ≥5 Years Ago:

• Administer tetanus toxoid-containing vaccine without TIG 2
• For patients aged ≥11 years who have not previously received Tdap or have unknown Tdap history, Tdap is preferred 2
• For patients with documented previous Tdap, either Td or Tdap may be used 2

If Never Immunized or Unknown Status:

• Administer tetanus toxoid-containing vaccine and consider TIG 3

Safety and Efficacy in Lupus Patients

• Tetanus toxoid vaccination is safe and effective in SLE patients, with no evidence of increased disease activity 1
• Approximately 90% of SLE patients (65 of 72) immunized with tetanus toxoid achieved a protective antibody response, which is very similar to the response rate in the general population 1, 4
• Serum concentrations of tetanus antitoxoid IgG are comparable between healthy controls and SLE patients 1
• EULAR recommends that SLE patients receive tetanus toxoid vaccine per the same guidelines as the general population 1

Impact of Immunosuppressive Medications

• In general, medications do not interfere with the development of protective antibody titers to tetanus toxoid vaccines 1
• Belimumab along with concomitant biologic agents (methotrexate, azathioprine, or mycophenolate) did not affect preexisting tetanus toxoid antibody titers 1
• Patients receiving rituximab more than 24 weeks before tetanus vaccination showed no significant change in humoral immunity response 1

Special Consideration for Recent Rituximab Use:

• If urgent tetanus protection is needed within 24 weeks of receiving rituximab, EULAR recommends passive immunization with tetanus immunoglobulin 1

Critical Clinical Pearls

• There is no urgency for tetanus toxoid administration in the acute setting—it provides protection against the next injury, not the current injury 3
• The tetanus vaccine can be administered at any point during wound management, as it takes weeks to generate protective antibodies 3
• Do not assume cat scratches are "clean wounds"—they should be treated as contaminated wounds requiring appropriate tetanus prophylaxis 2
• When both TIG and tetanus toxoid-containing vaccine are indicated, administer using separate syringes at different anatomical sites 2

Common Pitfalls to Avoid

• Do not withhold tetanus vaccination in lupus patients due to concerns about disease flare—inactivated vaccines like tetanus toxoid are safe and do not increase lupus disease activity 1
• Do not over-vaccinate: patients who received tetanus vaccine within the past 5 years do not need revaccination for contaminated wounds 2
• A documented case report exists of tetanus occurring after cat scratches in a previously immunized patient, emphasizing that even minor cat-related injuries warrant appropriate prophylaxis assessment 5