Elephantiasis, elephant-man syndrome
Elephantiasis is also called elephant-man syndrome. And at the latest this name describes the clinical picture memorable. In Elephantiasis tropica parts of the body can assume enormous - elephant-like - dimensions. The cause of this is a lymph congestion caused by roundworms that are transmitted by mosquitoes. A cure is not possible today, because the worms can not be completely eradicated. However, medications and surgical procedures can alleviate the symptoms.
Elephantiasis tropica occurs mainly in tropical Africa and in large parts of tropical Asia. Further morbidity is found in South and Southeast Asia, China, the Caribbean, South America and in the southeast of Indonesia. It is estimated that at least 100 million people worldwide are infected with filaria.
Tourists hardly endangered
For travelers, the risk of developing elephantiasis tropica is rather low. An infection is usually preceded by numerous mosquito bites over a long period of time. For safety reasons, travelers in risk areas should protect themselves from insect bites. Stable clothing, mosquito nets and anti-mosquito repellents help.
It may take years, or nearly decades, between the infection and the outbreak of elephantiasis tropica. During this time, the filaria ripen. Adult female adults can become up to 10 centimeters long (males to about 4 cm). They are up to 10 years old. The worms prefer to nest in the lymphatic glands and lymph nodes of the legs and in the subcutaneous fatty tissue of the abdomen and mate. Offspring in the form of microfilaria are detectable at the earliest 2 to 3 months after infection, usually much later. The microfilariae sometimes cause inflammatory, nettle-fever-like skin rashes.
More and more filariae occupy the lymphatic system
After months or years, the worms have increased so much that they repeatedly cause feverish lymph node and lymph node inflammation. The lymphatic vessels become visible and palpable as reddened, painful strands. Inflamed lymph nodes swell and hurt. For infections by roundworms of the genus Wuchereria, acute inflammatory bursts in the genital area are typical. They manifest as painful testicular, epididymis or spermatic cord inflammation (Meyer-Kouwenaarsches syndrome).
In the chronic course it comes up to 15 years to the characteristic Lymphstauungen at the legs as well as in the range of the strips and genitals. The scrotum swells painfully to a multiple of its original size (lymph node or hydrocele), inner and outer labia deform edentulous-edematous and the legs continue to increase in size (lymphedema). The more the lymphatic drainage is obstructed, the more pronounced is the typical elephant-like symptomatology (especially with Brugia infections).
In addition to the strong swelling, it often leads to other diseases. First and foremost, these result from the significantly weakened defense system. Bacteria and fungi easily play against the worm-infested lymphatic system. Especially bladder, kidney and airway inflammations are among the typical concomitant diseases of elephantiasis.
Sometimes the roundworms cause the so-called tropical pulmonary eosinophilia syndrome. This is characterized by nocturnal cough attacks and asthma attacks, chronic lung diseases such as COPD and pulmonary hypertension, recurrent attacks of fever, swelling of the liver and / or spleen, and a high concentration of eosinophils (certain form of defense cells) in the blood.
Elephantiasis tropica is caused by various types of whitish, filiform threadworms called filariae. Therefore, the disease belongs to the group of filarioses (roundworm diseases) or helminths (worm diseases)
The most common species of filaria are Wuchereria bancrofti, Brugia malayi and Brugia timori.
The worms are transmitted to humans through mosquito bites. There they enter the lymphatic system and trigger an inflammatory reaction. This causes the lymphatic vessels to become blocked or even destroyed. As a result, the lymphatic fluid can no longer flow away and build up. This leads to strong swelling of the affected areas. Especially the legs and external genitalia can enlarge abnormally.
A rarer cause of elephantiasis tropica is leprosy due to infection with Mycobacterium leprae.
Indirect transmission from person to person
Roundworms are not transmitted directly from person to person. Indirect transmission is possible. Once infected with roundworms, the female filariums lay several hundred eggs.The resulting larvae circulate as microfilariae via the bloodstream throughout the organism. If a mosquito now stabs, it picks up these larvae with their blood meal - and passes them on to another human at the next sting.
The suspected elephantiasis tropica usually results quickly when the doctor sees the swollen body parts. In addition, antibodies and an eosinophilia (increase in eosinophilic granulocytes, a defense cell form) can be detected in the blood.
Furthermore, microfilariae can be detected in the blood. The phrase "there is the worm in there" is to be taken literally in Elephantiasis tropica. The microfilaria test should be carried out at night between 10:00 pm and 2:00 am as the young worms prefer to migrate during the night hours. The best way to do this is to remove blood from the earlobe. Microfilariae are also detectable in skin and lymph nodes.
The therapy of elephantiasis tropica is medicated with antiparasitic or antibiotic agents. The drug of choice is diethylcarbamazine (DEC). DEC works against microfilariae and adult worms. But unfortunately not all infected: There are always so-called therapy failure. Other drugs against elephantiasis tropica are doxycycline and ivermectin.
In order to alleviate allergic reactions, additional corticosteroids such as prednisolone or antihistamines such as dimetinden may be used.
Lymphatic drainage and compression therapy
Patients with elephantiasis tropica should be regularly treated physiotherapeutically. First and foremost is manual therapy in the form of lymphatic drainage. It stimulates the lymph drainage, so that the pent-up lymph can drain better. In addition, a compression therapy with bandages or custom-made stockings relieves the discomfort.
In case of pronounced elephantiasis tropica lymphatic vessels can be transplanted microsurgically.
There is no vaccine against elephantiasis tropica. Therefore, the best prophylaxis is to protect yourself from mosquito bites. Stable clothing, mosquito nets and anti-mosquito repellents help.