Cat scratch disease: A study of eighty-three cases

Abstract

The chief points arising from this study of eighty-three cases of cat scratch disease are as follows: It is a benign infection, endemic not epidemic, with a subacute lymphadenitis as the chief clinical feature. Cats are much the most common vector. The causative organism is probably a virus but so far it has not been isolated. In this series a seasonal incidence is evident, most cases occurring in the period from October to January and almost none in May, June and July. Infectivity is low but cases may appear in the same household at intervals of a year or more. Multiple sites of adenopathy, usually neighbouring lymph node areas, are sometimes involved. Certain rather unusual features may be encountered: pain on moving joints, simulating arthritis; phlebitis; erythema nodosum; splenomegaly; encephalitis and eosinophilia. The skin test has definite limitations but is nonetheless an important confirmatory procedure. In this series the reaction to the lymphogranuloma venereum complement fixation test was usually negative in children but positive in about half of the patients tested who were over twenty-five years of age. When positive, it was a helpful confirmation of the diagnosis. No antibiotics have been found effective and they need not be given. If gross suppuration occurs, needle aspiration is the best treatment. The possibility of cat scratch disease should be considered in any patient with a subacute adenitis, particularly if axillary nodes are involved. In suspected cases of tuberculous adenitis, cat scratch disease should also be considered.