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Bartonellosis is a constellation of
clinical conditions affecting human beings and a variety of animals.
Many
Bartonella infections are zoonotic,
with some of the most commonly reported zoonotic manifestations of
infection including cat scratch disease, bacillary angiomatosis,
endocarditis, and neuroretinitis.
Five species of
Bartonella have been found to infect humans, henselae, quintana,
elizabethae, bacilliformis, and vinsonii.
The most common
of these in North America are Bartonella quintana and Bartonella
henselae, the agents of trench fever,
bacillary angiomatosis and
parenchymal peliosis, and in the case of B. henselae
cat-scratch disease.
B. bacilliformis
is endemic in Peru and Ecuador, where it causes oroya fever or
Carrion's disease.
Bartonellosis is
an infection by Bartonella bacilliformis , a small pleomorphic,
multiflagellated, gram-negative coccobacillus, which is the only
member of the genus Bartonella but is closely related to
certain animal pathogens.
The organisms parasitize erythrocytes in
vivo and can be cultured in semisolid media or in embryonated
eggs.
In smears of blood and in tissue sections stained with Giemsa or
Wright stain, the bacteria are reddish-violet. The organisms are small
coccobacilli, occasionally curved, and may aggregate in chains of
three or in “V” or “Y” forms.
The term bartonellosis encompasses two syndromes, both caused by B.
bacilliformis - Oroya fever, the acute anemic phase; and
verruga
peruana, the chronic dermal phase.
These present as a biphasic
pattern, with acute anemic first, followed some months later by the
chronic dermal phase. Either phase may occur by itself.
Visit:
verruga
peruana ;
cat-scratch disease
;
bacillary angiomatosis.
Bartonellosis
occurs only in Peru, Ecuador, and Colombia. The foci of endemic
transmission are river valleys in the Andes at an elevation between
700 and 2,500 meters.
The disease is transmitted by the sandflies
Phlebotomus verrucarum and Phlebotomus noguchi.
The vectors
are sensitive to drying and cold, hence the absence of bartonellosis
in coastal regions and at higher elevations.
Humans provide the only
reservoir and acquire bartonellosis at sunrise and sunset, when
sandflies are most active.
In endemic areas 10% to 15% of the
population have latent infections.
Newcomers are susceptible, where as
the indigenous population is resistant, a difference explained by subclinical infection and immunity in the indigenous people.
The
incubation period of the acute anemic stage is 3 weeks.
The onset is
abrupt with fever, skeletal pains, and a severe hemolytic anemia that
is often macrocytic.
Lymphadenopathy and hepatosplenomegaly are
usually present.
Reticulocytosis, jaundice, and other changes of
hemolytic anemia also occur.
The anemia can be profound, and the blood
erythrocyte count may fall in a few days from normal to less
than 500,000 / micro L.
Secondary septicemia caused by salmonellae
[Visit:
Salmonellosis (Gastroenteritis and Septicemia)] is
frequent and contributes to the high mortality of acute bartonellosis.
About 40% of patients with untreated bartonellosis die
in the anemic phase.
The dermal
eruptive phase of bartonellosis sometimes coexists with the anemic
phase, but they are usually separated by an asymptomatic interval of 3
to 6 months.
Occasionally the eruptive form develops independently
without prior evidence of bartonellosis.
The eruption is usually
military (forma miliar), and many small hemangioma like lesions
of the dermis balloon outward and cause a studded appearance. Nodular
lesions (forma nodular) are larger but fewer and may be more
prominent on the extensor surfaces of the arms and legs. At times, a
few large, deep-seated lesions, which tend to ulcerate, develop near
joints and limit motion. The eruptive phase is often prolonged, but
eventually heals spontaneously.
The mortality in eruptive phase is less
than 5%.
Grossly, the
acute phase causes changes characteristic of acute hemolytic anemia,
with prominent pallor and jaundice.
The bone marrow is hyperplastic.
Lymphadenopathy, hepatomegaly, and splenomegaly are present, caused
by the engorgement of the reticuloendothelial cells with bacteria,
erythrocytes, and hemosiderin.
Microscopically, the endothelial cells
of the spleen are swollen with phagocytosed bacteria and debris.
Thrombosis, with splenic infarcts and centrilobular hepatic necrosis,
may be present.
The diagnosis
is made by demonstrating the bacilli in blood smears or tissue
sections or by isolating the organism in cultures from blood or
tissue. Serologic tests are not useful.
Successful treatment of acute
hemolytic bartonellosis has been reported with chloramphenicol,
tetracycline, streptomycin, and penicillin but bacteremia is not
always eliminated by antimicrobial therapy. Antibiotic therapy of the
dermal eruptions has been less successful.
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Bartonellosis (Carrion's Disease) in the pediatric population of
Peru: an overview and update.Braz
J Infect Dis. 2004 Oct;8(5):331-9. Epub 2005 Mar 17.
Bartonellosis, or
Carrion's Disease, is an endemic and reemerging disease in Peru
and Ecuador. Carrion's Disease constitutes a health problem in
Peru because its epidemiology has been changing, and it is
affecting new areas between the highland and the jungle. During
the latest outbreaks, and previously in endemic areas, the
pediatric population has been the most commonly affected. In the
pediatric population, the acute phase symptoms are fever,
anorexia, malaise, nausea and/or vomiting. The main signs are
pallor, hepatomegaly, lymphadenopathies, cardiac murmur, and
jaundice. Arthralgias and weight loss have also commonly been
described. The morbidity and mortality of the acute phase is
variable, and it is due mainly to superimposed infections or
associated respiratory, cardiovascular, neurological or
gastrointestinal complications. The eruptive phase, also known as
Peruvian Wart, is characterized by eruptive nodes (which commonly
bleed) and arthralgias. The mortality of the eruptive phase is
currently extremely low. The diagnosis is still based on blood
culture and direct observation of the bacilli in a blood smear. In
the chronic phase, the diagnosis is based on biopsy or serologic
assays. There are nationally standardized treatments for the acute
phase, which consist of ciprofloxacin, and alternatively
chloramphenicol plus penicillin G. However, most of the treatments
are based on evidence from reported cases. During the eruptive
phase the recommended treatment is rifampin, and alternatively,
azithromycin or erythromycin.
Bartonella infection
in humans.Presse
Med. 1999 Feb 27;28(8):429-34, 438
BARTONELLA
BACILLIFORMIS: Among the 3 species of Bartonella known to be human
pathogens, B. bacilliformis causes Carriun's disease, which
manifests an acute phase (Oroya fever) and a chronic phase marked
by benign skin eruption with wart like macules of vascular origin.
Until 1993, B. bacilliformis was considered to be the only species
in Bartonella genus. In 1993, species formally in the Rochalimaea
genus were designated as Bartonella species. BARTONELLA QUINTANA:
This species causes trench fever. It is also the causal agent in
cases of bacillary angiomatosis, septicemia, endocarditis with
negative blood cultures, and chronic nodal infections,
particularly in immunosuppressed patients. Trench fever is
transmitted by body lice and is becoming more prevalent,
particularly in the homeless. BARTONELLA HENSELAE: This agent
causes bacillary angiomatosis, visceral peliosis, septicemia,
endocarditis and cat-scratch disease. Transmitted by cats, and
perhaps by lice, cat-scratch disease is one of the most frequent
zoonoses. OTHER SPECIES: The spectrum of Bartonella infections has
continued to widen these last 5 years. The role of B. elizabethae
and C. clarridgeiae as human pathogens remains to be defined.
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