Cat Scratch Disease

Excerpt

Cat scratch disease (CSD), also known as cat scratch fever, is a febrile illness primarily characterized by subacute regional lymphadenopathy caused by the intracellular, gram-negative bacillus Bartonella henselae. The infection often resolves spontaneously within 2 to 4 weeks in immunocompetent individuals, but more severe or disseminated forms can occur in both immunocompetent and immunocompromised hosts. CSD was first identified in the 1930s, with its link to cats recognized in the 1950s. Transmission mainly occurs through scratches or bites from infected cats, especially kittens, which carry B henselae in their claws and oral cavity, often transmitted among cats via fleas.

The hallmark clinical presentation includes a papule or pustule at the inoculation site, followed by tender regional lymphadenopathy proximal to it, frequently accompanied by low-grade fever. Considering CSD in the differential diagnosis of any acute, subacute, or chronic lymphadenopathy is important. The innate immune response, including activation of neutrophils and macrophages, plays a key role in local containment of the infection, typically resulting in granulomatous and suppurative lymphadenitis. Prevention focuses on flea control in cats and minimizing injuries caused by cats. Treatment depends on the severity of the illness and the patient's immune status, with antibiotic therapy reserved for complicated cases.