Cat-scratch disease

Cat scratch disease
Other names	Cat-scratch fever, felinosis, Teeny's disease, inoculation lymphoreticulosis, subacute regional lymphadenitis[1]
An enlarged lymph node in the armpit region of a person with cat-scratch disease, and wounds from a cat scratch on the hand.
Specialty	Infectious disease
Symptoms	Bump at the site of the bite or scratch, swollen and painful lymph nodes[2]
Complications	Encephalopathy, parotitis, endocarditis, hepatitis[3]
Usual onset	Within 14 days after infection[2]
Causes	Bartonella henselae from a cat bite or scratch[2]
Diagnostic method	Based on symptoms, blood tests[3]
Differential diagnosis	Adenitis, brucellosis, lymphogranuloma venereum, lymphoma, sarcoidosis[3]
Treatment	Supportive treatment, azithromycin[2][3]
Prognosis	Generally good, recovery within 4 months[3]
Frequency	1 in 10,000 people[3]

Cat-scratch disease (CSD) is an infectious disease that most often results from a scratch or bite of a cat.^[4] Symptoms typically include a non-painful bump or blister at the site of injury and painful and swollen lymph nodes.^[2] People may feel tired, have a headache, or a fever.^[2] Symptoms typically begin within 3–14 days following infection.^[2]

Cat-scratch disease is caused by the bacterium Bartonella henselae which is believed to be spread by the cat's saliva.^[2] Young cats pose a greater risk than older cats.^[3] Occasionally dog scratches or bites may be involved.^[3] Diagnosis is generally based on symptoms.^[3] Confirmation is possible by blood tests.^[3]

The primary treatment is supportive.^[3] Antibiotics speed healing and are recommended in those with severe disease or immune problems.^[2][3] Recovery typically occurs within 4 months but can require a year.^[3] About 1 in 10,000 people are affected.^[3] It is more common in children.^[4]