Bartonella infections
Bartonella species that cause disease in humans include B. bacilliformis, B. quintana, and B. henselae.
In immunocompetent patients, B. henselae infection (cat-scratch disease) presents as regional lymph node enlargement, with or without associated systemic disease. It is usually self-limiting, so most cases do not require antimicrobial therapy. Treatment is recommended in immunocompetent patients with: unresolved lymphadenopathy (lasting more than 1 month); lymphadenopathy associated with significant morbidity; systemic disease with organ involvement (eg liver, eye, neurological); or endocarditis. Diagnosis is usually based on serology or nucleic acid amplification testing (eg polymerase chain reaction [PCR]).
For unresolved lymphadenopathy, lymphadenopathy associated with significant morbidity, and systemic disease, use:
azithromycin 500 mg (child: 10 mg/kg up to 500 mg) orally on the first day, then 250 mg (child: 5 mg/kg up to 250 mg) orally, daily for a further 4 days. bartonella infection azithromycin
For endocarditis in adults and children 8 years or older, use:
doxycycline orally, 12-hourly for 6 weeks bartonella infection doxycycline
adult: 100 mg
child 8 years or older and less than 26 kg: 50 mg
child 8 years or older and 26 to 35 kg: 75 mg
child 8 years or older and more than 35 kg: 100 mg
PLUS EITHER
1 gentamicin (adult and child) 1 mg/kg intravenously, 8-hourly for 2 weeks. Monitor plasma concentration from the first dose—see Principles of aminoglycoside use for dosage adjustment and principles of use1 bartonella infection gentamicin
OR
2 rifampicin 300 mg (child: 7.5 mg/kg up to 300 mg) orally, 12-hourly for 2 weeks. For dosage adjustment in adults with kidney impairment, see rifampicin dosage adjustment. bartonella infection rifampicin
For treatment of endocarditis in children younger than 8 years, seek expert advice.
In severely immunocompromised patients, including those with advanced HIV infection, B. henselae and other Bartonella species cause skin disease (bacillary angiomatosis) and internal organ disease (bacillary peliosis). Such infection occurs rarely in immunocompetent patients. Treatment is essential—seek expert advice.
Treatment of infections caused by B. quintana (trench fever) and B. bacilliformis (Carrion disease or Oroya fever) is complex—seek expert advice.