Bartonella are intracellular bacterial pathogens that live primarily within the lining of blood vessels. Bartonella henselae can cause cat-scratch fever and endocarditis. It is tick-borne and a common Lyme disease coinfection.
A common sign of the illness are stretch-mark-like rashes that run more-or-less parallel on the skin.
Bartonellosis also sometimes triggers psychiatric manifestations.