Bartonella henselae (PCR)

smear, biopsy, pus, cerebrospinal fluid or EDTA blood

The bacterium Bartonella henselae is the causative agent of cat-scratch disease (bartonellosis). With cat-scratch disease most patients display a small, painless red papule at the site of inoculation (i.e. where the bite or scratch happened) which appears a few days to 2 weeks after the bite/scratch. In most cases, a painful lymphadenopathy (in most cases the axillary nodes are affected) follows which normally resolves in a few days. In some patients further symptoms like general discomfort, nausea, fever or loss of appetite can appear.

Long-lasting and systemic infections (e.g. bacillary angiomatosis and peliosis, hepatitis and pneumonitis) are possible in immunosuppressed individuals. Rarely, neurological manifestations (encephalitis, neuroretinitis) or endocarditis develop.

The most frequent vector is young cats, which usually show asymptomatic bacteraemia. Furthermore, pathogens have also been found in other mammals (e.g. dogs) as well as in cat fleas and ticks.