Clinical and pathologic evaluation of chronic Bartonella henselae or Bartonella clarridgeiae infection in cats

Human Bartonella infections result in diverse medical presentations, wherea s many cats appear to tolerate chronic bacteremia without obvious clinical abnormalities. Eighteen specific-pathogen-free cats Here inoculated with Ba rtonella henselae- and/or Bartonella clarridgeiae-infected eat blood and mo nitored for 454 days. Relapsing bacteremia did not correlate with changes i n protein profiles or differences in antigenic protein recognition. Intrade rmal skin testing did not induce a delayed type hypersensitivity reaction t o cat scratch disease skin test antigen. Thirteen cats were euthanatized at the end of the study. Despite persistent infection, clinical signs a ere m inimal and gross necropsy results were unremarkable. Histopathology reveale d peripheral lymph node hyperplasia (in all of the 13 cats), splenic follic ular hyperplasia (in 9 cats), lymphocytic cholangitis/pericholangitis (in 9 cats), lymphocytic hepatitis (in 6 cats), lymphoplasmacytic myocarditis (i n 8 cats), and interstitial lymphocytic nephritis (in 4 cats). Structures s uggestive of Bartonella Here visualized in some Warthin-Starry. stained sec tions, and Bartonella DNA. Has amplified from the brain node (from 6 of the 13 cats), liver (from 11 cats) heart (from 8 cats), kidney (from 9 eats), lung (from 2 cats), and brain (from 9 cats). This study indicates that B. h enselae or B. clarridgeiae can induce chronic infection following blood tra nsfusion in specific-pathogen-free cats and that Bartonella DNA can be dete cted in blood, brain, lymph node, myocardium, Ih er, and kidney tissues of both blood culture-positive cats and blood culture-negative cats. Detection of histologic changes in these cats supports a potential etiologic role fo r Bartonella species in several idiopathic disease processes in cats.