Key clinical aspects
This disease manifests itself mainly as a rather slow-healing ulcer with chronic lymphadenitis (98%) or rarely as a systemic condition (2%). An ulceroglandular syndrome which must be distinguished from tularemia, mycotic and mycobacterial infections. Sometimes there is Parinaud’s oculoglandular syndrome (which can resemble sarcoidosis) or one of the rarer forms, such as retinitis with papilloedema.
The condition is caused by Bartonella henselae and very rarely by Afipia felis. The latter pathogen derives its name from the “Armed Forces Institute of Pathology in the USA, where the bacterium was first identified in 1988. Infection is contracted by cat scratches or bites and possibly also by infected cat fleas. Bartonella henselae has also been recovered from ixodid ticks, though the role of ticks in transmission of bartonellosis is not clear yet. It is useful to know that cat bites can also transmit other dangerous infections such as plague, tularemia, sporotrichosis, nocardiosis and infections with Pasteurella multocida and Capnocytophaga canimorsus.
Bacteraemia with B. henselae can persist in cats for months (asymptomatic for the animal). A biopsy of the skin lesion or an affected lymph node can help to cement the diagnosis. Antibodies against B. henselae can be detected serologically. In lymphadenitis azithromycin for 5 days is first line treatment, alternatively clarithromycin, ciprofloxacin or doxycycline for 7-10 days can be used.
