"Elephantiasis" (Lymphatic Filariasis)

Eric M. Simpson

Dr. Jeffrey C. Burne

Biology 1134

July 6, 2011

Elephantiasis    

            Elephantiasis is a name sometimes used synonymously with the disease lymphatic filariasis. Elephantiasis, as the name implies, is a term coined to represent the condition of having a physical appearance in which body parts affected by lymphatic filariasis resemble those of an elephant. Most affected, are the extremities, but
other areas of the body may assume the disfiguring skin and tissue damage caused by filariasis. Filariasis is a parasitic infection caused by nematodes (roundworms) transmitted to humans by certain mosquitoes. Most filarial infections are asymptomatic. Lymphatic filariasis, however, morbidly scars victims with a grotesque and painful chronic injury. The injury of elephantiasis occurs because adult filariae worms obstruct some lymphatic circulation.

            Lymph, fluid removed from the interstitial spaces between tissue cells, returns to blood in the central circulation of the body. On average, approximately three liters of lymph fluid circulates through the body’s lymphatic system daily. Elephantiasis, a severe manifestation of lymphatic filariasis, occurs when adult filariae worms cluster along the pathways of the lymphatic circulation and obstruct the flow of lymph fluid. The obstructed fluid cannot circulate. Stagnation of fluid produces edema (swelling) in body tissues normally drained by the affected lymphatic vasculature. The edema hampers the normal blood supply to the affected tissues, and injury occurs as a result. Lymphedema is the swelling of tissues caused by obstructed lymphatic vessels. This obstructive lymphedema causes further lymph vessel damage, compromises the circulation of blood supplying skin and other tissues, and leads to distortion of the body. This swelling, with its subsequent distortion, causes tissue injury, and the skin thickens and hardens. It is this thickening and hardening of the skin—coupled with the disfiguring edematous appearance of the body—that gives lymphatic filariasis its name “elephantiasis”.

            Eight main species of mosquitoes are responsible for the transmission of lymphatic filariasis to humans. Three of these species cause most of the morbidity associated with lymphatic filariasis. The Wuchereria bancrofti is responsible for most of the cases, possibly about 90% of them. Although the Brugia timori is the vector in some cases, the Brugia malayi causes most of the rest of them. These arthropods infect hosts with the microfilariae (larvae of the nematode). Upon contact, mosquitoes introduce filarial larvae onto the skin of the host. The larvae then penetrate the bite wound. From there, they migrate into the victim’s bloodstream. Eventually, they travel into the lymph fluid. There, they can live for years, sometimes producing thousands of microfilariae daily. These microfilariae may mature into adult worms and cause the syndrome associated with lymphatic filariasis, or they may spread to another mosquito when the host is bit.

            Although elephantiasis is overt, some manifestations of lymphatic filariasis are less obvious. According to Progress report 2000-2010 and strategic plan 2010-2020 of the Global Programme to Eliminate Lymphatic Filariasis: halfway towards eliminating lymphatic filariasis (WHO), a report published in conjunction with the efforts of the World Health Organization, most cases of lymphatic filariasis are asymptomatic. According to this report, this disease threatens over “1.34” billion people in 81 countries, more than “120 million” people are infected, “40 million” people are disfigured and incapacitated, “15 million” people have lymphedema and “25 million” men have urogenital swelling (primarily scrotal hydrocele). These figures attest to the high number of people that show no symptoms of the disease. Although patients with asymptomatic microfilaremia (the presence of the larvae form of filariae in the blood) exhibit no external signs, these infections cause damage to the kidneys and the lymphatic system.

            Medicines can lesson susceptibility to acquiring elephantiasis, but once lymphedema occurs, treatment is limited. The National Lymphedema Network (NLN), in NLN Position Paper: Lymphedema Risk Reduction Practices, lists six main areas of focus to which the patient who suffers from lymphedema should adhere. These six areas focuses on properly caring for the skin and avoiding injury in order to reduce the risk of infection, modifying activity and lifestyle, avoiding constriction of the affected limb(s), proper use of compression garments, avoiding extremes of temperature,  and other practices specifically aimed at modifying the use of the lower extremities. The NLN acknowledge that these are recommendations based solely on pathophysiology and clinical experience. Hygiene, good skin care, exercise and elevation of the affected extremity are measures generally recommended for coping with the effects of lymphedema. Surgery is the cure for hydrocele (excess accumulation of fluid in the scrotum).

            Interrupting the transmission of the disease is the best means of prevention. Mass drug administration (MDA) to entire populations has lessened the prevalence of the disease in several countries. Strategic efforts to decrease the incidence of lymphatic filariasis have also included training health-care workers in proper care and treatment procedures, educating the community about awareness and intervention options, and the distribution of insecticidal mosquito nets for sleeping purposes.

For those with lymphedema, their condition is chronic. People never completely recover from the affliction. Although there is not a cure for lymphedema, early diagnosis and treatment does improve outcome. Acute localized inflammatory reactions involving the skin, lymph nodes and lymph vessels re-occur frequently. Pain accompanies both the chronic and the acute cases. Accompanying physical pain, the anguish of disability and humiliation is tantamount. Often, both employment and managing the routine activities of daily living are impossible to accomplish.

            Having elephantiasis does not mean having the reputed memory of an elephant. In fact, the disease is one many people may would prefer to forget, for elephantiasis is on the list of neglected tropical diseases. Presumably, these neglected tropical diseases are “neglected” because most of them affect the world’s poorest people. The poorest people are also the people who are most at risk of contracting lymphatic filariasis, for they tend to lack health care, sanitation and good-quality water. Fortunately, global efforts are underway to eradicate the disease, and much progress is occurring. The pharmaceutical companies GlaxoSmithKline and Merck & Company, Incorporated have pledged to donate medicine for ‘as long as it takes’ to eliminate the disease. Many philanthropists have pledged finances to aid in combating this disease. Since the year 2000, the transmission of lymphatic filariasis had dropped by “43%” (WHO). Although there has been a significant decrease in disease transmission, some people—especially those who suffer debilitating effects from the disease—when contemplating current events, may still think that there is “an elephant in the room”.

Works Cited

National Lymphedema Network. http://www.lymphnet.org/pdfDocs/nlntreatment.pdf. Web.30 June 2011

WHO Library Cataloguing-in-Publication Data. “Progress report 2000-2009 and strategic plan 2010-2020 of the global programme to eliminate lymphatic filariasis: halfway towards eliminating lymphatic filariasis” http://whqlibdoc.who.int/publications/2010/9789241500722_eng.pdf. Web. 29 June 2011