Cat scratch disease

Introduction. 

Infections by Bartonella bacteria cause several fever-like illnesses in humans, including Carrión Disease, Trench fever and Cat-scratch disease. Cat scratch disease is a mild illness caused by Bartonella henselae. It can be transmitted by flea bites from an infected animal (zoonotic), but often direct contact with an animal is sufficient. Children are commonly infected. 

Summary

• Cause: Bartonella henselae
• Microscopy: Gram-negative short rods
• Transmission: Flea vector or direct contact with infected animal (zoonotic)
• Symptoms: Sore at infection site; fever, local lymphadenopathy
• Complications: bacteremia, Bacillary angiomatosis
• Pathogenesis: Intracellular pathogen: Penetration of bacteria into RBCs and endothelial cells; inflammation of local lymph nodes
• Treatment: does not respond to antibiotics