(See also Overview of Bartonella Infections.)
Endemic only to the Andes Mountains in Colombia, Ecuador, and Peru, both Oroya fever and verruga peruana are passed from human to human by the Phlebotomus sandfly.
Symptoms of Oroya fever include fever and profound anemia, which may be sudden or indolent in onset. The anemia is primarily hemolytic, but myelosuppression also occurs. Muscle and joint pain, severe headache, and often delirium and coma may occur. Superimposed bacteremia caused by Salmonella or other coliform organisms may occur. Mortality rates may exceed 50% in untreated patients.
Diagnosis of Oroya fever is confirmed by blood cultures.
Because Oroya fever is often complicated by Salmonella bacteremia, chloramphenicol 500 to 1000 mg orally every 6 hours for 7 days is the treatment of choice;, but Salmonella resistance to chloramphenicol is an emerging problem. Some clinicians add another antibiotic, typically doxycycline or a beta-lactam, but trimethoprim/sulfamethoxazole (TMP/SMX), macrolides, and fluoroquinolones have also been used successfully.
Verruga peruana manifests as multiple skin lesions that strongly resemble bacillary angiomatosis; these raised, reddish purple skin nodules usually occur on the limbs and face. The lesions may persist for months to years and may be accompanied by pain and fever.
Verruga peruana is diagnosed by its appearance and sometimes by biopsy showing dermal angiogenesis.
Treatment with most antibiotics produces remission, but relapse is common and requires prolonged therapy.
Typical treatment for verruga peruana is rifampin 10 mg/kg orally once a day for 10 to 14 days or streptomycin 15 to 20 mg/kg IM once a day for 10 days. Ciprofloxacin 500 mg orally 2 times a day for 7 to 10 days has been used successfully, as have azithromycin, doxycycline, and trimethoprim/sulfamethoxazole.