Differential Diagnosis for Pediatric Patient Scratched by Cat
Single Most Likely Diagnosis
- Cat Scratch Disease (Bartonellosis): This is the most common and likely diagnosis, caused by the bacterium Bartonella henselae, which is transmitted through cat scratches or bites. It typically presents with a papule or pustule at the site of the scratch, followed by regional lymphadenopathy.
Other Likely Diagnoses
- Cellulitis: A bacterial skin infection that can occur after a cat scratch, characterized by redness, swelling, warmth, and tenderness of the skin.
- Abscess: A collection of pus that can form at the site of the scratch, often requiring drainage.
- Staphylococcal or Streptococcal Infections: Bacterial infections caused by Staphylococcus or Streptococcus species, which can lead to conditions like impetigo or erysipelas.
Do Not Miss Diagnoses
- Rabies: Although rare, rabies is a deadly viral disease that can be transmitted through the scratch of an infected animal, making prompt recognition and treatment crucial.
- Tetanus: A bacterial infection caused by Clostridium tetani, which can enter the body through wounds, including scratches. It's essential to ensure the child's tetanus vaccination is up to date.
- Pasteurella multocida Infection: A bacterial infection that can cause severe disease, including sepsis, especially in individuals with compromised immune systems.
Rare Diagnoses
- Capnocytophaga canimorsus Infection: A bacterial infection that can be transmitted through animal bites or scratches, more commonly associated with dog bites but can occur with cat scratches, especially in immunocompromised individuals.
- Erysipeloid: A rare bacterial infection caused by Erysipelothrix rhusiopathiae, which can be transmitted through contact with infected animals, including cats.
- Actinomycosis: A rare chronic bacterial infection that can affect the skin and other tissues, potentially acquired through animal scratches or bites.