Bacillary angiomatosis (BA) is a form of

angiomatosis Angiomatosis is a non-neoplastic condition characterised by nests of proliferating capillaries arranged in a lobular pattern, displacing adjacent muscle and fat. It consists of many angiomas. These tend to be cavernous hemangiomas, which are shar ...

associated with bacteria of the genus ''

Bartonella ''Bartonella'' is a genus of Gram-negative bacteria. It is the only genus in the family Bartonellaceae. Facultative intracellular parasites, ''Bartonella'' species can infect healthy people, but are considered especially important as opportunis ...

''.

Symptoms

Cutaneous BA is characterised by the presence of lesions on or under the skin. Appearing in numbers from one to hundreds, these lesions may take several forms: * papules or nodules which are red, globular and non-blanching, with a vascular appearance * purplish nodules sufficiently similar to

Kaposi's sarcoma Kaposi's sarcoma (KS) is a type of cancer that can form masses in the skin, in lymph nodes, in the mouth, or in other organs. The skin lesions are usually painless, purple and may be flat or raised. Lesions can occur singly, multiply in a limite ...

that a

biopsy A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a diseas ...

may be required to verify which of the two it is * a purplish lichenoid plaque * a subcutaneous nodule which may have ulceration, similar to a bacterial

abscess An abscess is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends b ...

While cutaneous BA is the most common form, it can also affect several other parts of the body, such as the brain, bone, bone marrow, lymph nodes, gastrointestinal tract, respiratory tract, spleen, and liver. Symptoms vary depending on which parts of the body are affected; for example, those whose livers are affected may have an

enlarged liver Hepatomegaly is the condition of having an enlarged liver. It is a non-specific medical sign having many causes, which can broadly be broken down into infection, hepatic tumours, or metabolic disorder. Often, hepatomegaly will present as an abdomi ...

and

fever Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...

, while those with osseous BA experience intense pain in the affected area.

Presentation

BA is characterised by the proliferation of blood vessels, resulting in them forming tumour-like masses in the skin and other organs.

Causes

It is caused by either ''

Bartonella henselae ''Bartonella henselae'', formerly ''Rochalimæa henselae'', is a bacterium that is the causative agent of cat-scratch disease ( bartonellosis). ''Bartonella henselae'' is a member of the genus ''Bartonella'', one of the most common types of bacte ...

'' or '' B. quintana''. * ''B. henselae'' is most often transmitted through a

cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

scratch or bite, though

tick Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by ...

s and

flea Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, a ...

s may also act as vectors. * ''B. quintana'' is usually transmitted by

lice Louse ( : lice) is the common name for any member of the clade Phthiraptera, which contains nearly 5,000 species of wingless parasitic insects. Phthiraptera has variously been recognized as an order, infraorder, or a parvorder, as a result o ...

. It can manifest in people with

AIDS Human immunodeficiency virus infection and acquired immunodeficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV), a retrovirus. Following initial infection an individual m ...

and rarely appears in those who are immunocompetent.

Diagnosis

Diagnosis is based on a combination of clinical features and biopsy. Neutrophilic infiltrate.

Treatment and prevention

While curable, BA is potentially fatal if not treated. BA responds dramatically to several antibiotics. Usually,

erythromycin Erythromycin is an antibiotic used for the treatment of a number of bacterial infections. This includes respiratory tract infections, skin infections, chlamydia infections, pelvic inflammatory disease, and syphilis. It may also be used duri ...

will cause the skin lesions to gradually fade away in the next four weeks, resulting in complete recovery.

Doxycycline Doxycycline is a broad-spectrum tetracycline class antibiotic used in the treatment of infections caused by bacteria and certain parasites. It is used to treat bacterial pneumonia, acne, chlamydia infections, Lyme disease, cholera, typhus, an ...

may also be used. However, if the infection does not respond to either of these, the medication is usually changed to

tetracycline Tetracycline, sold under various brand names, is an oral antibiotic in the tetracyclines family of medications, used to treat a number of infections, including Acne vulgaris, acne, cholera, brucellosis, plague (disease), plague, malaria, and sy ...

. If the infection is serious, then a bactericidal medication may be coupled with the antibiotics If a cat is carrying ''Bartonella henselae'', then it may not exhibit any symptoms. Cats may be bacteremic for weeks to years, but infection is more common in young cats. Transmission to humans is thought to occur via flea feces inoculated into a cat scratch or bite, and transmission between cats occurs only in the presence of fleas. Therefore, elimination and control of fleas in the cat's environment are key to prevention of infection in both cats and humans.

History

The condition that later became known as bacillary angiomatosis was first described by Stoler and associates in 1983. Being unaware of its infectious origin, it was originally called ''epithelioid angiomatosis''. Following documentation of bacilli in Warthin-Starry stains and by electron microscopy in a series of cases by LeBoit and colleagues, the term bacillary angiomatosis was widely adopted.

References

External links

{{Bacterial cutaneous infections Bacterium-related cutaneous conditions