1. Take the MRSA Quiz!
2. Strep or Sore Throat Slideshow Pictures
3. Infectious Mononucleosis Slideshow Pictures

Medical Author:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

View Full Profile

Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

View Full Profile

Most cases of CSD are diagnosed by the patient's clinical presentation and history. If the patient has a history of cat scratches (or superficial bites or a cat licking their face or cuts) and then develops papules or pustules, many physicians consider these findings enough to diagnose CSD. If the patient also develops swollen lymph nodes and fever, these findings reinforce the clinical diagnosis of CSD. Microscopic examination with special stains of biopsied tissue (lymph nodes) may show small curved Gram-negative rods, but the staining methods do not yield a definitive diagnosis of CSD. Laboratory tests are also available; indirect fluorescent antibody and rising immunoglobulin titers may provide additional evidence for infection with Bartonella henselae but are not frequently done. A polymerase chain reaction (PCR) test to detect the genetic material of the bacteria that shows good sensitivity and specificity for Bartonella can be done on the patient's tissue, but the test is not widely available.

Although laboratory tests are infrequently used, their availability is important because about 10% of patients with CSD do not recall or state an association with cats or kittens. This lack of clinical history makes the diagnosis of CSD difficult. These tests can help physicians differentiate CSD from other diseases caused by organisms similar to Bartonella (for example, Anaplasma phagocytophilum and Acinetobacter baumanni, which are both small pleomorphic Gram-negative bacilli) or from other diseases that have some similar symptoms (for example, swollen lymph nodes in lymphoma or in Actinobacillosis).

Must Read Articles Related to Cat Scratch Disease

Antibiotics Antibiotics are prescribed to individuals to cure disease by killing bacteria. There are over 100 antibiotics. The main classes of antibiotics include penicilli...learn more >>

Fever in Adults A fever is a body temperature of 100.4 F or greater. A fever may be caused by a virus, bacteria, fungus, blood clot, tumor, drug, or the environment. Treatment ...learn more >>

Fever in Children Fever is defined as a rectal temperature over 100.4 F or 38.0 C. Fever isn't life-threatening unless it is persistently high -- greater than 107 F rectal temper...learn more >>

See the Entire Cat Scratch Disease Topic Guide »