Serological evidence of Bartonella spp. infection in the UK

We reviewed serological and epidemiological data relating to 1000 consecuti ve patients from whom specimens were submitted for estimation of bartonella antibodies, using MRL Diagnostics Bartonella IFA IgM and IgG kits. Using 2 89 control sera, we estimated the specificity of the kits as greater than o r equal to 99.0 %. Evidence of bartonella infection was found in 16.3 % of patients examined. Rates varied by patient group: 20 % of patients for whom a diagnosis of cat scratch disease (CSD) was considered probable had evide nce of infection, as did 10.4 % of patients with 'possible CSD', 8.1 % of p atients with possible bacillary angiomatosis, 18.2 % of patients with 'cult ure negative' endocarditis and 17.6 % of patients with possible bartonellos is with ophthalmic involvement. An IgM response was seen in 6.6 % of patien ts and IgG in 15.1 %. Cases were more frequent among males than females (18 .5 % vs. 13.9 %). Analysis by age showed that although rates of infection w ere highest in the decades 0-9 years (19.4 %) and 10-19 years (20.7 %), the y fell only slightly in the next three decades. MRL bartonella kits appears to provide a useful and specific approach to the diagnosis of these infect ions.