Ocular complications of cat scratch disease.

Cat scratch disease (CSD) in humans is caused by infection with Bartonella henselae or other Bartonella spp. The name of the disease reflects the fact that patients frequently have a history of contact (often involving bites or scratches) with infected cats. Patients with CSD typically develop lesions at the site where the skin is broken together with regional lymphadenopathy but may go on to exhibit systemic symptoms and with deep-seated infections at a range of sites including the eye. Patients with CSD may present with a range of inflammatory eye conditions, including Parinaud's oculoglandular syndrome, neuroretinitis, multifocal retinitis, uveitis and retinal artery occlusion. Bartonella spp. are fastidious bacteria that are difficult to culture from clinical specimens so microbiological diagnosis is frequently made on the basis of positive serology for anti-Bartonella antibodies or detection of bacterial DNA by PCR. Due to the lack of clinical trials, the evidence base for optimal management of patients with CSD-associated eye infections (including the role of antibiotics) is weak, being derived from single reports or small, uncontrolled case series.