What is the first line treatment for Cat Scratch Disease when lymphadenopathy is severe?

The first-line treatment for Cat Scratch Disease, particularly when lymphadenopathy is severe, is azithromycin. This condition is caused by the bacterium Bartonella henselae, typically transmitted through scratches or bites from infected cats. Azithromycin is favored in cases of severe lymphadenopathy due to its efficacy against this specific organism, which can lead to significant inflammatory responses, such as swollen lymph nodes.

While other antibiotics like doxycycline can be effective in certain situations, particularly in adults or when treating additional complications, azithromycin has shown particular effectiveness in alleviating symptoms associated with severe lymphatic involvement. It is often well-tolerated, has good tissue penetration, and can lead to quicker resolution of symptoms in affected individuals.

Other options, such as amoxicillin and atovaquone, are not considered first-line treatments for this disease. Amoxicillin is typically used for conditions caused by different bacteria, while atovaquone is primarily an antiparasitic agent rather than an antibiotic for bacterial infections. Therefore, azithromycin stands out as the most appropriate first-line therapy in managing severe cases of Cat Scratch Disease.