Click here to view next page of this article

 

Unusual and Zoonotic AIDS-Associated Infections


Bartonella (Rochalmaea) Infections

Vascular proliferative manifestations
occur in immunocompromised bacillary angiomatosis (BA), peliosis hepatis

Relapsing bacteremia

in both immunocompetent and immunocompromised

first described as trench fever (World War I, B. quintana)

with or without endocarditis (culture-negative)

Granulomatous lymphadenitis

immunocompetent or early HIV infection
also known as cat scratch disease (CSD)
Bartonella (Rochalimaea) Species, 2006 (nine)
small, fastidious gram-negative rod
B. quintana (causes BA, trench fever)
B. henselae (causes BA, CSD)
B. elizabethae (causes endocarditis)
B. bacilliformis (causes disease only in South America)
B. clarridgeiae (most recently identified species)
B. vinsonii (dog)
B. grahamii
B. doshiae
B. taylorii
Manifestations of Bartonella Infection in late HIV Infection
BA occurs late in HIV infection, usually when CD4 <100
BA affects skin, bone, lymph node, brain, lung
bacillary-peliosis hepatis affects spleen, liver

Cutaneous BA has diverse Presentations-vascular

may resemble KS
subcutaneous nodule
friable vascular lesion
red papule
pedunculated lesion
deep subcutaneous mass
Osseous Ba
extremely painful
osteolytic lesions on x-ray
bone scan positive
very vascular
Bacillary peliosis hepatis
vascular proliferative lesion of liver and/or spleen
may occur concomitantly with cutaneous BA/splenic peliosis
accompanied by pancytopenia, thrombocytopenia and/or ascites
Bartonella can cause fever of unknown origin

we found about 12% are Bartonella sero- or cx-positive

 

Manifestations in early HIV/Immunocompetent host

Cat Scratch Disease (CSD)-most common Bartonella Infection

granulomatous lymphadenitis
papule, followed by lymphadenopathy
malaise/low-grade fever
occasionally severe disease
very high fever
encephalopathy with coma
hepatosplenic granulomatous lesions
stellate retinitis

epidemiology

22,000 cases in US annually, mostly immunocompetent
worldwide distribution
CSD bacillus conclusively identified to be B. henselae

BH DNA present in five CSD skin test preparations found by Perkins 1992

Bartonella antibodies present in 88% of CSD patients found by Regnery 1992
BH isolated from CSD lymph nodes by Dolan in 1993
CSD statistically associated with traumatic cat contact (Zangwill 1992)

 

Manifestations in early OR late HIV Infection

Bacteremia

often relapsing

relapse may occur regardless of antibiotic treatment

clusters of B. quintana bacteremia

found in homeless, alcoholics
trench fever (due to B. quintana) occurred in thousands of troops in WWI
endocarditis (more common in immunocompetent)

Bartonella is a cause of "culture-negative" endocarditis

3 of 4 recent cases required valve replacement
up to 4% of endocarditis cases in Lyon, France (immunocompetent)

 

Laboratory Diagnosis

for Lymphadenopathy in early HIV

biopsy is mainstay of diagnosis in HIV with LAN
need to r/o other causes with path and cultures
(NOTE: biopsy may be contraindicated in immunocompetent pts with CSD)

for late-stage HIV and cutaneous lesions

Must BX to Distinguish BA from KS, other infections
for multiple hypodense lesions on CT c/w peliosis hepatis

Ddx includes lymphoma, KS, MAC, P. carinii

look for other tissue to biopsy (eg, cutaneous BA, LN)
if liver biopsy, need caution due to potential for hemorrhage
histopathology