By Gary M. White, MD

Bacillary Angiomatosis Courtesy Caroline Thornton, MD

Bacillary angiomatosis (BA) represents an angioproliferation caused by infection by gram-negative organisms of the genus Bartonella. It classically occurs in HIV-positive patients.

Of interest, cat scratch disease is caused by B. henselae. B. henselae and B quintana differ by only five nucleotide substitutions in a partial RNA sequence. B. quintana was the louse-born agent of the epidemic trench fever during the First World War. It is not surprising then that BA caused by B. quintana is more common in those with low income, homelessness, and exposure to lice. Those with BA from B. henselae more likely have been exposed to cats or fleas. There is no evidence that any tick transmits bacillary angiomatosis.

BA tends to affect immunocompromised patients. Bacillary angiomatosis can also occur in the immunocompetent patient or in the immunocompromised patient with or without HIV (e.g., leukemia). In one study, BA tended to occur late in the course of HIV infection and was associated with anemia, CD4 less than 200, and elevated alkaline phosphatase [Clin Inf Dis 1996;22;794].

Verruga peruana is identical clinically and histologically.


Solitary or multiple reddish-purple papulonodules in a patient with AIDS is characteristic. Pyogenic granuloma-like lesions and subcutaneous nodules may also occur. Blanching is frequent and bleeding is seen. Numerous lesions may occur with numbers as high as the thousands. Rarely, plaques and tumors resembling KS, papular angiokeratoma-like lesions, or soft subcutaneous nodules develop [BJD 1997;136;60].


Systemic symptoms including fever, chills, malaise, headache, and anorexia may occur. Systemic involvement of the liver, spleen, bone, brain, etc., are reported and is called parenchymal bacillary peliosis. Peliosis hepatitis is almost exclusively found in BA caused by B. henselae. Subcutaneous and lytic bone lesions are strongly associated with BA from B. quintana [NEJM 1997;337;1876].


The most common entity in the differential diagnosis is Kaposi's sarcoma. The histologic picture may suggest the diagnosis. It may be confirmed by silver stain (e.g., Warthin-Starry) identifying the organisms, electron microscopy showing the organisms, or PCR. PCR may be performed in conjunction with the CDC, Atlanta. Grocott-Gomori methenamine-silver nitrate stain is a simple and satisfactory alternative to Warthin-Starry staining.


Referral to an infectious disease specialist is in order. Erythromycin 500 mg QID for a prolonged course is usually given. Clarithromycin (e.g., 250 mg BID) is effective. Azithromycin, doxycycline 100 mg BID, and minocycline may also be used. Improvement of the patient's immune system is of course beneficial.


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A 29-year-old man with HIV. Am J Trop Med Hyg. 2014 Sep 3; 91(3): 439


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