Cat-scratch disease is a common, benign condition, most often caused by Bartonella henselae. It is transmitted by a bite or scratch of a kitten or a cat with fleas or occasionally, that of an other pet. Peak transmission is in the early fall or winter. The condition characteristically affects children and adults younger than 21 years. The vast majority of patients can recall a history of cat contact, but not all. Typically, within 2 to 3 days of inoculation, a papule develops and progresses to a vesicle, which is followed by proximal lymphadenopathy in about two weeks. Rarely, the primary lesion at the site of inoculation is pustular or nodular. In fewer than 6% of patients, the primary lesion is followed by a generalized macular-papular and morbilliform eruption. The involved lymph nodes are tender, often with overlying erythema; occasionally they can suppurate. The lymphadenopathy subsides spontaneously after several months. The diagnosis of cat-scratch disease is primarily clinical.
Differential Diagnosis: Cat-scratch disease can be distinguished from cutaneous anthrax in the following manner.
*Patient has had contact with kittens or cats with fleas
* Occurrence is in fall or winter
* Primary lesion is a papule or vesicle
* Lymph node histopathology is characteristic of the disease
*Ulcer with eschar is painless
* Ulcer and eschar are surrounded by characteristic non-pitting edema
Used with Permission from W.B. Saunders
Color Atlas of Dermatology
Search PIER® - Decision Support
ACP Members Only. Decision support for over 460 clinical topics.
Quality Improvement Programs: Our Center for Quality develops programs to bridge the gap between research and practice.
Adult Immunization: Inform, Implement, Immunize: ACP's Immunization Outreach Program
Educators: Let Annals assist you with your teaching activities!
Annals for Educators Alerts include Clinical Practice Points, Quality Improvement, Humanism and Professionalism, and a MKSAP Morning Report question derived from MKSAP 16. Find out more!
Earn ABIM Practice Assessment Points
ACP now offers a variety of ABIM recertification resources to help you earn ABIM Maintenance of Certification Practice Assessment points!
See the resources on our Webpage.