Elephantiasis affects more than 120 million people worldwide with over 40 million severely disfigured. It is not a specific disease, but rather a syndrome caused by chronic obstruction of lymphatics. The most common cause is lymphatic filariasis, which is caused by the thread-like worms Wuchereria bancrofti, Brugia malayi, and Brugia timori. The infection is transmitted to humans by mosquitoes. Adult worms lodge in the lymphatics, disrupting the fluid balance between tissues and blood vessels, causing lymphedema of the extremities, breast, or genitourinary (GU) system. The infection is generally acquired in childhood, although clinical manifestations may take years to develop. Adult worms live 4 to 6 years, producing millions of blood circulating microfilariae. Acute symptoms of lymphadenopathy and dermal inflammation may precede and later accompany chronic swelling. With persistent infection and inflammation, the skin develops a hyperkeratotic, pebbly, or warty appearance that may become ulcerated and darkened. Bacterial and fungal superinfections contribute to morbidity.
Mosquito nets and insect repellants are the main means of prevention of lymphatic filariasis. Parasites may be detected microscopically in the blood, but the nocturnal periodicity makes identification challenging. Eosinophilia is common but is nonspecific. Availability of a rapid card test that identifies circulating antigens has overcome this problem and is available in some endemic areas.
Management and Disposition
Treatment of lymphatic filariasis depends on the presence or absence of other filarial organisms and includes various combinations of albendazole, ivermectin, and diethylcarbamazine. Cleansing of the affected areas and topical antibiotics aid in thwarting secondary disease. Local massage and elevation of the extremity improve lymphatic flow.
Elephantiasis bears a heavy social burden due to physical limitations, disfigurement, sexual disability, and social stigmatization. Affected patients may be shunned by their families, are often unwed, and are unable to work.
Testicular hydrocele is the most common manifestation of chronic W bancrofti infection for males in endemic areas.
Symptomatic filariasis is occasionally seen in travelers, even in those with only short-term stays in endemic regions.
W bancrofti occasionally causes an acute asthma-like condition known as tropical pulmonary eosinophilia.
Podoconiosis is a noninfectious cause of elephantiasis that occurs in people who walk barefoot in areas with large amounts of volcanic ash. Kaposi sarcoma is another emerging cause of nonfilarial elephantiasis in sub-Saharan Africa.
Elephantiasis. Unilateral lymphatic filariasis. Note diffuse edema with early evidence of chronic skin changes. (Photo contributor: Lawrence B. Stack, MD.)
Elephantiasis. Late-stage bilateral elephantiasis with chronic nodular skin changes. (Photo contributor: Seth W. Wright, MD.)
Elephantiasis. Large hydrocele from lymphatic filariasis in a man from Haiti. (Photo contributor: Seth W. Wright, MD.)