Bacillary angiomatosis, first recognized in 1983, and associated illnesses
(e.g., peliosis hepatica) are caused by bacteria of the genus
Bartonella, most commonly Bartonella
henselae and Bartonella quintana.
Seven other Bartonella species exist
and several have been associated with bacteremia and endocarditis, but none are
seen with increased frequency in HIV-1-- infected persons.
Cases
of bacillary angiomatosis in patients with HIV-1 infection have been linked to
cat exposure. Bartonella quintana,
previously known as Rochalimaea quintana,
is associated with louse infestation, causes trench fever , and is increasingly
frequent among the homeless and under conditions of poor sanitation.
Bacillary
angiomatosis occurs most often late in HIV-1 infection in patients with a
median CD4+ T lymphocyte count of <50 cells/µL
in the majority of case series . Bartonellosis is often a chronic illness with
disease lasting for months to years in the majority of patients.
Clinical
Manifestations
Bartonella
species have been associated with infections involving every organ system, but
the characteristic presentation is bacillary angiomatosis of the skin.
Bacillary angiomatosis resembles Kaposi sarcoma. Lesions are often papular,
red, with smooth or eroded surfaces, are vascular and bleed if traumatized.
Nodules might be observed in the subcutaneous tissue and can erode through the
skin. Bone infection has been reported, and such infections are notable in that
they are lytic and painful . Bartonella
infection of the liver produces hepatic bacillary peliosis, characterized by
vascular masses in the liver or spleen.
Although
isolated organ systems might be the principle focus of disease, infection
results from hematogenous dissemination, and systemic symptoms of fever,
sweats, fatigue, malaise, weight loss, and other symptoms might accompany
localized syndromes.
Diagnosis
Diagnosis
is confirmed by histopathologic examination of tissue biopsy specimens .
Lesions produce vascular proliferative histopathology; modified silver stain
demonstrates numerous bacilli. Tissue Gram stain or acid-fast staining is
negative.
Serologic
tests exist and are available through CDC . Serologic tests are often positive
for many years before the development of symptoms, underscoring the chronicity
of infection or indicating reactivation disease in the setting of
immunosuppression.
Bartonella
spp. can
be isolated from blood by using lysis centrifugation . The organisms are
difficult to isolate from tissue. Growth requires at least 3 weeks in 5% CO2.
PCR methods have been developed for the identification and speciation of
Bartonella but are only available as research tools.
Treatment
Recommendations
No
randomized, controlled clinical trials have evaluated antimicrobial treatment
of bartonellosis. Erythromycin and doxycycline have been used successfully to
treat bacillary angiomatosis, peliosis hepatica, bacteremia, and osteomyelitis
and are considered first-line treatment for bartonellosis on the basis of
reported experience in case series
(AII). Therapy should last at least
3 months (AII). Doxycyline is the
treatment of choice for central nervous system bartonellosis (AIII).
Clarithromycin or azithromycin have been associated with clinical response in
certain cases and are considered second line alternatives (BII),
although treatment failures have been reported with both drugs.
The
beta-lactams (penicillins and first-generation cephalosporins) have no
appreciable in vitro activity and
are not recommended for treatment of bartonellosis (DII).
Quinolones have variable in vitro activity and clinical response in case
reports; as a result, they are not generally recommended as first-line therapy
but might be tried as second-line alternatives (CIII).
Management
of Treatment Failure
Among
patients who fail to respond to initial treatment, one or more of the
second-line alternative regimens should be considered (AIII).
Among patients who relapse, lifelong therapy is recommended (AIII).
Prevention
of Recurrence
Relapse
or reinfection with Bartonella has
sometimes followed a course of primary treatment. Although no firm
recommendation can be made about secondary prophylaxis (chronic maintenance
therapy) in this setting, long-term suppression of infection with erythromycin
or doxycycline should be considered (CIII).
Special
Considerations During Pregnancy
Pregnancy
has been associated with a more severe course and possible increased risk for
death with acute infection caused by B.
bacilliformis in immunocompetent patients . No data are available on
the potential impact of pregnancy on Bartonella
infections among HIV-1--infected persons. Similarly,
B. bacilliformis infections during pregnancy might increase the risk
for spontaneous abortion and stillbirth and can be transmitted to the fetus. No
data are available on the effect of other Bartonella
infections on pregnancy outcome.
Diagnosis
of Bartonella infections in pregnant
women should be the same as in nonpregnant adults. Treatment during pregnancy
should be with erythromycin rather than tetracyclines because of the increased
hepatotoxicity and staining of fetal teeth and bones associated with the use of
tetracyclines during pregnancy (AIII).
Cephalosporins are not recommended.