cat scratch disease

see also:

• lymphadenopathy
• https://www.cdc.gov/healthypets/diseases/cat-scratch.html

• cat scratch fever or cat scratch disease is caused by a bacteria Bartonella henselae present in the saliva of some cats which enters the human via a scratch, or on the open eye - in which case a granulomatous conjunctivitis with preauricular LNs (Parinaud's syndrome) may occur.
• it is a common cause of chronic swollen lymph nodes in children, and most cases occur in children or adolescents presumably as they have the most contact with cats
• the usual 1st clue is the tender regional lymphadenopathy which usually occurs 2-3 weeks later and there may be a small papule at the scratch site
• they may have constitutional symptoms of fever, malaise, fatigue, headache, loss of appetite, sore throat, weight loss
• splenomegaly may be found
• the Bartonella henselae IFA serology test is highly accurate for identifying infection caused by this bacteria
• Rx is usually with azithromycin (particularly in patients with AIDS when the infection is more serious) although most cases are self-limiting after some months
• in immunocompromised people, there is a risk of complications such as encephalitis, neuroretinitis, and osteomyelitis