Bacillary angiomatosis
Encyclopedia
Bacillary angiomatosis is a form of angiomatosis
associated with bacteria of the Bartonella
genus.
or Bartonella quintana
.
It can manifest in people with AIDS
and rarely appears in those who are immunocompetent.
While cutaneous BA is the most common form of BA, BA 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
and fever
, while those with osseous BA will experience intense pain in the affected area.
BA responds dramatically to several antibiotics. Usually, erythromycin
will cause the skin lesions to gradually fade away in the next four weeks, resulting in complete recovery. Doxycycline
may also be used. However, if the infection does not respond to either of these, the medication is usually changed to tetracycline. 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.
Angiomatosis
Angiomatosis is a non-neoplastic condition presenting with little knots of capillaries in various organs. It consists of many angiomas. It is also known as Von Hippel-Lindau Disease and is a rare genetic multi system disorder characterized by the abnormal growth of tumours in the body...
associated with bacteria of the Bartonella
Bartonella
Bartonella is a genus of Gram-negative bacteria. Facultative intracellular parasites, Bartonella species can infect healthy people but are considered especially important as opportunistic pathogens. Bartonella are transmitted by insect vectors such as ticks, fleas, sand flies and mosquitoes...
genus.
Causes
It is caused by either Bartonella henselaeBartonella henselae
Bartonella henselae, formerly Rochalimæa, is a proteobacterium that can cause bacteremia, endocarditis, bacillary angiomatosis, and peliosis hepatis. It is also the causative agent of cat-scratch disease which, as the name suggests, occurs after a cat bite or scratch...
or Bartonella quintana
Bartonella quintana
Bartonella quintana, originally known as Rochalimaea quintana, and "Rickettsia quintana", is a microorganism that is transmitted by the human body louse. This microorganism is the caustative agent of trench fever...
.
- Bartonella henselae is most often transmitted through a catCatThe cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
scratch or bite, though tickTickTicks are small arachnids in the order Ixodida, along with mites, constitute the subclass Acarina. Ticks are ectoparasites , living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians...
s and fleaFleaFlea is the common name for insects of the order Siphonaptera which are wingless insects with mouthparts adapted for piercing skin and sucking blood...
s may also act as a vector. - Bartonella quintana is usually transmitted by lice.
It can manifest in people with AIDS
AIDS
Acquired immune deficiency syndrome or acquired immunodeficiency syndrome is a disease of the human immune system caused by the human immunodeficiency virus...
and rarely appears in those who are immunocompetent.
Presentation
BA is characterised by the proliferation of blood vessels, resulting in them forming tumour-like masses in the skin and other organs.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 sarcomaKaposi's sarcomaKaposi's sarcoma is a tumor caused by Human herpesvirus 8 , also known as Kaposi's sarcoma-associated herpesvirus . It was originally described by Moritz Kaposi , a Hungarian dermatologist practicing at the University of Vienna in 1872. It became more widely known as one of the AIDS defining...
that a biopsyBiopsyA biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
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 abscessAbscessAn abscess is a collection of pus that has accumulated in a cavity formed by the tissue in which the pus resides due to an infectious process or other foreign materials...
While cutaneous BA is the most common form of BA, BA 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
Hepatomegaly is the condition of having an enlarged liver. It is a nonspecific medical sign having many causes, which can broadly be broken down into infection, direct toxicity, hepatic tumours, or metabolic disorder. Often, hepatomegaly will present as an abdominal mass...
and fever
Fever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
, while those with osseous BA will experience intense pain in the affected area.
Treatment and prevention
While curable, it is potentially fatal if not treated.BA responds dramatically to several antibiotics. Usually, erythromycin
Erythromycin
Erythromycin is a macrolide antibiotic that has an antimicrobial spectrum similar to or slightly wider than that of penicillin, and is often used for people who have an allergy to penicillins. For respiratory tract infections, it has better coverage of atypical organisms, including mycoplasma and...
will cause the skin lesions to gradually fade away in the next four weeks, resulting in complete recovery. Doxycycline
Doxycycline
Doxycycline INN is a member of the tetracycline antibiotics group, and is commonly used to treat a variety of infections. Doxycycline is a semisynthetic tetracycline invented and clinically developed in the early 1960s by Pfizer Inc. and marketed under the brand name Vibramycin. Vibramycin...
may also be used. However, if the infection does not respond to either of these, the medication is usually changed to tetracycline. 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.