Which organism is responsible for cat scratch disease?

Cat scratch disease is primarily caused by the organism Bartonella henselae. This bacterium is a small, fastidious, gram-negative bacillus that is transmitted to humans primarily through scratches or bites from infected cats, particularly young or sick cats. Symptoms typically include fever, lymphadenopathy, and a characteristic papule or pustule at the site of injury.

Bartonella henselae is specifically adapted to colonize cats and can remain in their bloodstream, which facilitates the transmission to humans. The recognition of this bacterium as the causative agent is crucial for proper diagnosis and management of cat scratch disease, distinguishing it from infections caused by other organisms such as Staphylococcus aureus, Escherichia coli, or Salmonella enterica, which are associated with different types of infections and do not lead to cat scratch disease.

Understanding the specific pathogen involved helps healthcare providers to approach patient education and treatment effectively, focusing on resolving symptoms and preventing further transmission, while recognizing the unique nature of the infection linked to interactions with felines.