| Elephantiasis | |
|---|---|
| Classification and external resources | |
"Bellevue Venus" Oscar G. Mason's portrait of a woman with elephantiasis. |
|
| ICD-10 | B74.0 (ILDS B74.01) I89 |
| ICD-9 | 125.9, 457.1 |
| DiseasesDB | 4824 |
| eMedicine | derm/888 |
| MeSH | D004605 |
Elephantiasis (/ˌɛlɨfənˈtaɪ.əsɨs/ el-i-fən-ty-ə-sis) is a disease that is characterized by the thickening of the skin and underlying tissues, especially in the legs and male genitals. In some cases the disease can cause certain body parts, such as the scrotum, to swell to the size of a softball or basketball.[1] It is caused by filariasis or podoconiosis.[2]
The proper medical term for the disease is elephantiasis.[3] It is commonly misheard as "Elephantitis", which substitutes for the ending -iasis (meaning process or resulting condition) the more commonly heard -itis (irritation or inflammation), resulting in "Elephantitis" meaning "inflammation of the elephant".
Contents |
Elephantiasis leads to marked swelling of the lower half of the body.
Elephantiasis occurs in the presence of microscopic, thread-like parasitic worms such as Wuchereria bancrofti, Brugia malayi, and B. timori, all of which are transmitted by mosquitoes.[4] However, the disease itself is a result of a complex interplay between several factors: the worm, the symbiotic Wolbachia bacteria within the worm, the host’s immune response, and the numerous opportunistic infections and disorders that arise. Consequently, it is common in tropical regions and Africa. The adult worms only live in the human lymphatic system.[5] Obstruction of the lymphatic vessels leads to swelling in the lower torso, typically in the legs and genitals. It is not definitively known if this swelling is caused by the parasite itself, or by the immune system's response to the parasite.
Alternatively, elephantiasis may occur in the absence of parasitic infection. This nonparasitic form of elephantiasis is known as "nonfilarial elephantiasis" or "podoconiosis", and areas of high prevalence have been documented in Uganda, Tanzania, Kenya, Rwanda, Burundi, Sudan, Egypt and Ethiopia.[6] The worst affected area is Ethiopia, where up to 6% of the population is affected in endemic areas.[7][8] Nonfilarial elephantiasis is thought to be caused by persistent contact with irritant soils: in particular, red clays rich in alkali metals such as sodium and potassium and associated with volcanic activity.[9][10]
According to medical experts the worldwide efforts to eliminate lymphatic filariasis is on track to potentially be successful by 2020.[11] An estimated 6.6 million children have been prevented from being infected, with another estimated 9.5 million in whom the progress of the disease has been stopped.
For podoconiosis, international awareness of the disease will have to rise before elimination is possible. Podoconiosis does not yet appear on the Neglected Tropical Disease lists,and is not part of the work of organizations such as the World Health Organization.
Treatments for lymphatic filariasis differ depending on the geographic location of the endemic area.[12] In sub-Saharan Africa, albendazole is being used with ivermectin to treat the disease, whereas elsewhere in the world, albendazole is used with diethylcarbamazine.[12] Geo-targeting treatments is part of a larger strategy to eventually eliminate lymphatic filariasis by 2020.[12]
Another form of effective treatment involves rigorous cleaning of the affected areas of the body. Several studies have shown that these daily cleaning routines can be an effective way to limit the symptoms of lymphatic filariasis. The efficacy of these treatments suggests that many of the symptoms of elephantiasis are not directly a result of the lymphatic filariasis but rather the effect of secondary skin infections.
In addition, surgical treatment may be helpful for issues related to scrotal elephantiasis and hydrocele. However, surgery is generally ineffective at correcting elephantiasis of the limbs.
A vaccine is not yet available but is likely to be developed in the near future.
Treatment for podoconiosis consists of consistent shoe-wearing (to avoid contact with the irritant soil) and hygiene - daily soaking in water with an antiseptic (such as bleach) added, washing the feet and legs with soap and water, application of ointment, and in some cases, wearing elastic bandages. Antibiotics are used in cases of infection.
In 2003 it was suggested that the common antibiotic doxycycline might be effective in treating lymphatic filariasis.[13] The parasites responsible for elephantiasis have a population of symbiotic bacteria, Wolbachia, that live inside the worm. When the symbiotic bacteria are killed by the antibiotic, the worms themselves also die.
Clinical trials by the Liverpool School of Tropical Medicine in June 2005 reported that an 8 week course almost completely eliminated microfilariaemia.[14]
Lymphatic filariasis affects over 120 million people, primarily in Africa and South-East Asia, with about 40 million disfigured and incapacitated by the disease.[15]
| “ | Many people in Malabar, Nayars as well as Brahmans and their wives — in fact about a quarter or a fifth of the total population, including the people of the lowest castes — have very large legs, swollen to a great size; and they die of this, and it is an ugly thing to see. They say that this is due to the water through which they go, because the country is marshy. This is called pericaes in the native language, and all the swelling is the same from the knees downward, and they have no pain, nor do they take any notice of this infirmity. | ” |
|
—-Tomé Pires, Suma Oriental, 1512–1515.[16] |
||
Elephantiasis caused by lymphatic filariasis is one of the most common causes of disability in the world.[12] In endemic communities, approximately 10 percent of women can be affected with swollen limbs and 50 percent of men can suffer from mutilating genital disease.[12]
In areas endemic for podoconiosis, prevalence can be 5% or higher.
On September 20, 2007, geneticists mapped the genome or genetic content of Brugia malayi - the roundworm which causes elephantiasis (lymphatic filariasis). Figuring out the content of the genes might lead to development of new drugs and vaccines.[17]
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||