Cat-scratch disease in Northern Italy: atypical clinical manifestations in humans and prevalence of Bartonella infection in cats

In this paper, we report an investigation on cat-scratch disease (CSD) in Northern Italy. Seventy-four cases of CSD were diagnosed at the San Matteo hospital, Pavia, during the period 2005-2010. Of these 74 patients, 18 (24.3 %) reported atypical clinical manifestations such as ocular papillitis, maculopapular eruptions, vertebral infection, pulmonary infiltrates, and granulomatous hepatitis. Contact with cats was documented for 61 patients (82.4 %), while cat-related trauma was reported for 49 patients (66.2 %). We subsequently investigated the presence of Bartonella infection in cats belonging to the above patients and in other domestic and stray cats from three provinces of Northern Italy. Among the 27 domestic cats tested, nine of the 11 belonging to the CSD patients and two of the remaining 16 were infected by B. henselae (81.8 % vs. 12.5 %). Out of over 1,300 stray cats examined, 23.1 % were seropositive for B. henselae; after culturing and genotyping, 17 % were found to be infected by B. henselae (15.5 %) or B. clarridgeiae (1.5 %).