elephantiasis

Elephantiasis (Greek ελεφαντίασις, from ελέφαντας, "the elephant") is a syndrome that is characterized by the thickening of the skin and underlying tissues, especially in the legs and genitals. Elephantiasis generally results from obstructions of the lymphatic vessels. It is most commonly caused by a parasitic disease known as lymphatic filariasis.

Alternatively, elephantiasis may occur in the absence of parasitic infection. This nonparasitic form of elephantiasis, known as nonfilarial elephantiasis or podoconiosis, generally occurs in the mountains of central Africa. Nonfilarial elephantiasis is thought to be caused by persistent contact with volcanic ash. Elephantiasis partially takes its name from "the Elephant Man", the carnival stage name of Joseph Merrick. The name refers to the resemblence of Merrick's limbs to the thick, baggy skin on the limbs and trunks of elephants. However, Merrick's deformity was not actually caused by elephantiasis, but by a completely different medical problem called Proteus Syndrome.

Lymphatic Filariasis

Lymphatic filariasis is by far the most common cause of elephantiasis. Organisms that cause lymphatic filariasis are Wuchereria bancrofti, Brugia malayi, and Brugia timori, all of which are nematodes (i.e., roundworms) transmitted by mosquitoes. Most patients with lymphatic filariasis are infected with W. bancrofti.

In patients with lymphatic filariasis, the parasite occupies lymph vessels that drain the lower extremities, producing massive enlargement and deformity of the legs and genitalia. However, it is unclear whether the swelling that occurs results from the obstruction of these lymphatic vessels or, alternatively, from the immune response to the parasite and their endosymbiotic bacteria, Wolbachia, which are discussed below.

Lymphatic filariasis currently affects around 120 million people in 80 countries, and 40 million of these people have been seriously infected with the disease ^{citation needed]}. This disease is extremely rare in Western countries and is found almost exclusively in the tropics.

When lymphatic filariasis is caused by infection with Wuchereria bancrofti, it may be referred to as bancroftian filariasis. Infection with Brugia malayi results in a syndrome that is virtually identical, while Onchocerca volvulus causes many disorders in addition to elephantiasis.

Treatment

Medicines to treat lymphatic filariasis are most effective when used soon after infection, but they do have some toxic side effects. In addition, the disease is difficult to detect early. Therefore, improved treatments and laboratory tests are needed.

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 effectiveness 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.

Also, 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 and is unlikely to be developed in the near future.

Antibiotics as a possible treatment

In 2003 it was suggested that the common antibiotic doxycycline might be effective in treating elephantiasis^[1]. 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 in June 2005 by the Liverpool School of Tropical Medicine reported that an 8 week course almost completely eliminated microfilariaemia.^[2][3]

References and notes

• National Institutes of Health, USA
• Antibiotics help combat Elephantiasis

1. ^ Hoerauf A, Mand S, Fischer K, Kruppa T, Marfo-Debrekyei Y, Debrah AY, Pfarr KM, Adjei O, Buttner DW (2003). "Doxycycline as a novel strategy against bancroftian filariasis-depletion of Wolbachia endosymbionts from Wuchereria bancrofti and stop of microfilaria production". Med Microbiol Immunol (Berl) 192 (4): 211-6. PMID 12684759.
2. ^ Taylor MJ, Makunde WH, McGarry HF, Turner JD, Mand S, Hoerauf A (2005). "Macrofilaricidal activity after doxycycline treatment of Wuchereria bancrofti: a double-blind, randomised placebo-controlled trial". Lancet 365 (9477): 2116-21. PMID 15964448.
3. ^ Outland, Katrina. "New Treatment for Elephantitis: Antibiotics", The Journal of Young Investigators, 2005 Volume 13.