What is the recommended treatment for a cat scratch?

Treatment for Cat Scratches

The recommended treatment for a cat scratch is immediate thorough wound cleaning followed by application of a topical antibiotic such as bacitracin 1-3 times daily, with oral antibiotics (azithromycin as first-line) reserved for cases where infection develops. 1, 2

Immediate Care for Cat Scratches

1. Clean the wound thoroughly:

   • Wash the affected area immediately with soap and water 1
   • Deep irrigation to remove potential contaminants
   • Remove any necrotic tissue if present

2. Apply topical antibiotic:

   • Apply a small amount of bacitracin (equal to the surface area of a fingertip) to the area 1-3 times daily 2
   • May be covered with a sterile bandage
   • For children under 2 years of age, consult a doctor before applying topical antibiotics 2

Monitoring for Infection

Monitor the scratch site for signs of infection, which may include:

• Development of a papule or pustule at the scratch site (appears 3-30 days after exposure) 1
• Regional lymphadenopathy (typically develops about 3 weeks after inoculation) 1
• Redness, swelling, warmth, or increasing pain at the site
• Fever or systemic symptoms

Treatment if Infection Develops (Cat Scratch Disease)

If signs of infection develop, particularly lymphadenopathy suggestive of cat scratch disease (caused by Bartonella henselae):

1. First-line antibiotic treatment:

   • Azithromycin: 500 mg on day 1, followed by 250 mg for 4 additional days (for patients >45 kg)
   • For patients <45 kg: 10 mg/kg on day 1, followed by 5 mg/kg for 4 more days 1

2. Alternative antibiotics:

   • Erythromycin: 500 mg four times daily
   • Doxycycline: 100 mg twice daily
   • Treatment duration: 2 weeks to 2 months (minimum 3 months recommended for severe cases) 1

3. For cat bite/scratch with signs of cellulitis:

   • Amoxicillin-clavulanate: 875/125 mg twice daily
   • For penicillin-allergic patients: doxycycline 100 mg twice daily 1

Special Considerations

• Immunocompromised patients:

  • Require more aggressive treatment and monitoring
  • Longer antibiotic courses (>3 months) are recommended 1
  • Should take extra precautions when interacting with cats 3, 1

• Diabetic patients:

  • May benefit from prophylactic antibiotics: amoxicillin-clavulanate 875/125 mg orally twice daily for 5-7 days 1

• Follow-up:

  • Clinical reassessment within 24-48 hours if lymphangitis or edema develops 1
  • Be aware that lymphadenopathy may persist for 1-6 months despite appropriate treatment 1

Prevention of Future Cat Scratches

• Avoid rough play with cats 1
• Keep cats' nails trimmed 1
• Implement proper flea control for cats (fleas can transmit Bartonella between cats) 3, 1
• Do not allow cats to lick open wounds 3, 1
• Wash hands thoroughly after handling cats 3, 1
• For immunocompromised individuals, consider avoiding cat ownership or adopt cats >1 year of age 3

Clinical Pitfalls

• Most cases of cat scratch disease in immunocompetent hosts are self-limited and may not require antibiotic therapy 4, 5
• Diagnosis of cat scratch disease may be delayed as antibodies may not be detectable for up to 6 weeks after infection 1
• Cat scratch disease can occasionally present with atypical manifestations including ocular involvement, persistent fever, hepatosplenic infection, encephalopathy, or osteomyelitis 4, 5
• Immunocompromised patients are at risk for more severe manifestations such as bacillary angiomatosis or bacillary peliosis 4, 6