Cat scratch disease
Cat scratch disease is a disease caused by bartonella bacteria. It is believed to be transmitted by cat scratches and bites, or exposure to cat saliva.
CSD; Cat scratch fever; Bartonellosis
Causes, incidence, and risk factors
Cat scratch disease is caused by Bartonella henselae. The disease is spread through contact with an infected cat (a bite or scratch), or contact with cat saliva on broken skin or the white of the eye.
About 2 - 3 weeks after becoming infected, lymph node swelling (lymphadenopathy) occurs near the site of the scratch or bite.
A person who has had contact with a cat may show common symptoms, including:
- Bump (papule) or blister (pustule) at site of injury (usually the first sign)
- Fever (in some patients)
- Lymph node swelling near the scratch or bite
- Overall discomfort (malaise)
Less common symptoms may include:
Signs and tests
If you have swollen lymph nodes and a scratch or bite from (or have been in contact with) a cat, the health care provider may suspect cat scratch disease. A physical examination may reveal an enlarged spleen (splenomegaly).
The disease often goes unrecognized because of the difficulty in testing. However, the Bartonella henselae IFA test is highly accurate for identifying infection caused by this bacteria.
Other tests used in the diagnosis of cat scratch disease:
- Lymph node biopsy to rule out other causes of swollen glands
Generally, cat scratch disease is not serious. Medical treatment is not usually needed. In severe cases, treatment with antibiotics such as azithromycin can be helpful.
In AIDS patients and other people who have a suppressed immune system, cat scratch disease is more serious, and treatment with antibiotics is recommended.
In children with normal immune systems, full recovery without treatment is the norm. In immunocompromised people, treatment with antibiotics generally leads to recovery.
Calling your health care provider
Call your health care provider if you have enlarged lymph nodes and a history of exposure to a cat.
Avoiding contact with cats prevents the disease. Where this is not reasonable, good hand-washing after playing with a cat, avoiding scratches and bites, and avoiding cat saliva will lessen the risk of infection.
Schutze GE, Jacobs RF. Bartonella species (cat-scratch disease). In: Long SS, Pickering LK, Prober CG. Principles and Practice of Pediatric Infectious Diseases. 3rd ed. Philadelphia, Pa: Churchill Livingstone Elsevier; 2008: chap: 160.
Slater LN, Welch DF. Bartonella, including cat-scratch disease. In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 6th ed. Philadelphia, Pa: Churchill Livingstone Elsevier; 2005: chap 232.
Reviewed By: Linda Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School, Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.