Cat-scratch disease

The so-called "cat scratch disease" It is an infectious disease produced by a bacterium of the genus Bartonella (mainly B. henselae). It usually runs a benign course and is self-limiting, although the bacteria can remain in the infected person. It most often occurs in children after one to two weeks, following a scratch or bite by a cat. The disease was described in 1889 by Henri Parinaud, who described the oculo-glandular form.

Transmission

The cat was identified as a natural reservoir of the disease in 1950 by Robert Debré. Small cats carry the etiologic agent in their blood. However, studies have shown that fleas act as a vector for disease transmission between cats, and that B. henselae are excreted in the feces of cat fleas. Another study showed that cats can be infected by intradermal inoculation using flea feces infected with B. henselae. Therefore, it is believed that the most likely means of transmission of B. henselae from cats to humans may be due to inoculation with flea feces infected with B. henselae through a cat scratch wound or through mucous membranes. Although the presence of Bartonella DNA in ticks has been documented, there is no evidence that the disease can be transmitted by these arthropods.

Clinical manifestations

The most common symptoms of infection occur regionally as pain and swelling of the lymph nodes, a condition called regional lymphadenopathy. A papule may form in the area of inoculation. Only some patients have fever and other systemic symptoms. Other symptoms such as headache, chills, back pain, and abdominal pain may occur.

Most cases are benign or self-limited, but lymphadenopathy may persist for a few months after other symptoms have resolved. In general, the prognosis is favorable. The disease usually resolves spontaneously with or without treatment within a month. In immunocompromised patients, more serious complications may occur.

It is the most common cause of chronic adenopathies (swollen glands) (lasting more than 3 weeks) in children and young adults after contact with cats.

Treatment

For most cases of cat scratch disease, it has become difficult to establish the efficacy of a specific treatment, because the disease is self-limited and symptoms usually resolve without treatment. Azithromycin has been shown to accelerate the disappearance of lymphadenopathy caused by the disease. In patients with more severe disease, other antibiotic schemes have shown efficacy, such as azithromycin or doxycycline in combination with rifampicin.