Clinical implication of prolonged fever in children with cat scratch disease

Cat scratch disease, caused by Bartonella henselae, typically presents with a localized lymphadenopathy with a brief period of fever and general symptoms. However, there are atypical cases with a wide spectrum of clinical manifestations including prolonged fever (or =37.5 degrees C, for more than 7 days), or with systemic complication, or without lymphadenopathy. We analyzed relationships among those manifestations in children with cat scratch disease. A total of 127 patients were serologically diagnosed as having Bartonella infection between 1997 and 2003. Relationships among clinical manifestations were analyzed by use of multiple regression and multiple logistic regression analyses. Of the 127 seropositive cases, 75 (59.1%) had typical cat scratch disease and 52 (40.9%) had an atypical one. As atypical manifestations, 46 (36.2%) had prolonged fever, 23 (18.1%) had no lymphadenopathy, and 21 (16.5%) had complications: hepatic/splenic abscesses or low-echoic lesions, hepatic granuloma, and central nervous system involvements. Prolonged fever was observed in 20 (87%) of the 23 cases without lymphadenopathy and 16 (76.2%) of the 21 cases with complications. By multiple regression analysis, the duration of fever was significantly associated with both the absence of lymphadenopathy and the presence of complications. The child suffering from cat scratch disease without lymphadenopathy or with complication tends to have prolonged fever. Conversely, when a child has a prolonged fever of unknown origin, possibility of cat scratch disease should be considered, and a search for underlying systemic complications is recommended for prompt diagnosis and appropriate treatment.