Bartonella species are gram-negative bacteria previously classified as Rickettsiae. They are facultative intracellular organisms that typically live within red blood cells (RBCs) and endothelial cells. They cause several uncommon diseases (see table Some Bartonella Infections):
Regional lymphadenitis and constitutional symptoms (cat-scratch disease)
An acute febrile anemia (Oroya fever)
A chronic skin eruption (verruga peruana)
A chronic cutaneous eruption (bacillary angiomatosis)
Disseminated disease (trench fever)
Many people who are affected by the some of these infections are immunocompetent, but disseminated bartonellosis tends to occur in immunocompromised people.
Bartonella infection (bartonellosis) is usually acquired by humans via an insect vector.
Some Bartonella Infections
Species | Manifestations* | At Risk | Insect Vector | Treatment |
|---|---|---|---|---|
B. henselae, B. quintana | Multiple papules and subcutaneous nodules (purple to bright red skin lesions) Disseminated visceral disease Lymphadenopathy Hepatosplenomegaly | Immunocompromised patients | Lice, fleas | |
B. quintana | Prolonged or recurrent fever | People living in conditions of crowding or poor hygiene Immunocompromised patients | Body louse | |
B. henselae | Regional lymphadenopathy, painless papules Fever Endocarditis (often in patients who have had a predisposing valvular heart disorder) Encephalopathy Neuroretinitis | Owners of cats Immunocompromised patients | Possibly cat fleas (which also transmit the organism among cats) | |
Oroya fever, verruga peruana (Carrión disease) | ||||
B. bacilliformis | Oroya fever: Acute febrile hemolytic anemia Verruga peruana: Skin lesions similar to those in bacillary angiomatosis Salmonella bacteremia Secondary infections | Residents of the Andes Mountains at elevations of 600–2400 m | Phlebotomus sandflies | |
* In normal host. | ||||
† Treatment of uncomplicated cat-scratch disease is not usually required in patients with a normal immune system, but it is often given to possibly decrease the duration of symptoms (1). | ||||
