Cat scratch

Cat Scratch

Cat scratch, also known as cat scratch disease (CSD), is an infectious disease that results from a scratch or bite of a cat. It is caused by the bacterium *Bartonella henselae*. This condition is characterized by the development of a mild infection at the site of the scratch or bite, followed by swelling of the lymph nodes near the site of the injury.

Etiology

Cat scratch disease is primarily caused by the bacterium *Bartonella henselae*. Cats, especially kittens, are the primary reservoir for this bacterium. The bacteria are transmitted to humans through scratches, bites, or licks from an infected cat. Fleas play a significant role in the transmission of *Bartonella henselae* among cats.

Clinical Presentation

The clinical presentation of cat scratch disease can vary, but it typically includes:

• A papule or pustule at the site of the scratch or bite, appearing 3-10 days after the injury.
• Regional lymphadenopathy, which is the swelling of lymph nodes near the site of the scratch or bite. This usually occurs 1-3 weeks after the initial skin lesion.
• Fever, fatigue, and malaise may also be present.

In some cases, cat scratch disease can lead to more severe complications, such as:

• Parinaud's oculoglandular syndrome, which involves conjunctivitis and swollen lymph nodes near the eyes.
• Encephalopathy, which is a rare but serious complication involving inflammation of the brain.

Diagnosis

Diagnosis of cat scratch disease is primarily clinical, based on the history of cat exposure and the presence of characteristic symptoms. Laboratory tests that may aid in diagnosis include:

• Serology to detect antibodies against *Bartonella henselae*.
• Polymerase chain reaction (PCR) testing to identify bacterial DNA.
• Biopsy of affected lymph nodes in atypical cases.

Treatment

Most cases of cat scratch disease are self-limiting and do not require specific treatment. However, in cases with severe symptoms or complications, the following treatments may be considered:

• Antibiotics such as azithromycin, doxycycline, or rifampin.
• Analgesics and antipyretics for symptomatic relief.
• Aspiration of lymph nodes to relieve pain and pressure.

Prevention

Preventive measures to reduce the risk of cat scratch disease include:

• Avoiding rough play with cats, especially kittens.
• Washing hands thoroughly after handling cats.
• Keeping cats indoors to reduce their exposure to fleas.
• Using flea control products on cats.

Also see

• Bartonella henselae
• Lymphadenopathy
• Zoonotic disease
• Flea control