Lymphatic Filariasis (W. Bancrofti, B. Malayi)

Lymphatic filariasis (overview of filarial infections) is an infection with one of three types of Filarioidea. The acute symptoms consist of fever, lymphadenitis, lymphangitis, Funikulitis and epididymitis. There may be chronic ailments such as lung abscess, hyperkeratosis, polyarthritis, hydrocele, lymphedema and elephantiasis. Another manifestation of the disease is the tropical pulmonary eosinophilia with bronchospasm, fever and pulmonary infiltrates. The diagnosis is made by detection of microfilariae in the blood, ultrasound of adult worms or serological tests. The treatment with diethylcarbamazine; Antibiotics are used in complex bacterial cellulitis.

Lymphatic filariasis (overview of filarial infections) is an infection with one of three types of Filarioidea. The acute symptoms consist of fever, lymphadenitis, lymphangitis, Funikulitis and epididymitis. There may be chronic ailments such as lung abscess, hyperkeratosis, polyarthritis, hydrocele, lymphedema and elephantiasis. Another manifestation of the disease is the tropical pulmonary eosinophilia with bronchospasm, fever and pulmonary infiltrates. The diagnosis is made by detection of microfilariae in the blood, ultrasound of adult worms or serological tests. The treatment with diethylcarbamazine; Antibiotics are used in complex bacterial cellulitis. The etiology lymphatic filariasis is caused by Wuchereria bancrofti, Brugia malayi and B. timori. Transmission is by mosquito. originating from mosquitoes infective larvae migrate to the lymphatic vessels, where they develop within 6-12 months threadlike adult worms. The females are 80 to 100 mm long, males about 40 mm. Gravid adult females produce microfilariae, which circulate in the blood. The Bancroft filariasis occurs in tropical and subtropical areas of Africa, Asia, the Pacific and the Americas, incl. Haiti. The Brugia filariasis is endemic in South and Southeast Asia. Current estimates suggest that about 120 million people are infected. Symptoms and signs An infection can lead to Mikrofilariämie without clinical manifestations. Signs and symptoms are caused primarily by adult worms. The Mikrofilariämie slowly disappears after people have left the endemic area. An acute inflammatory filariasis consists of 4- to 7-day episodes (often rekurrierend) with fever and lymph node inflammation with lymphangitis (so-called. Adenolymphangitis acute, ADL) or acute epididymitis with inflammation of the spermatic cord. A localized involvement of a limb can lead to abscess formation drained externally and leaves a scar. ADL is often associated with secondary bacterial infections. ADL episodes usually go to the start of a chronic disease requires more than two decades. Acute filariasis severe than with locals in previously unexposed immigrants to endemic areas. After many years, a chronic filariasis can develop. In most patients there is a asymptomatic enlargement of lymphatic vessels, but it can lead to a chronic lymphedema of the body affected regions also due to a chronic inflammatory response to adult worms and secondary bacterial infections. Increased local sensitivity to bacterial and fungal infections further contributes to its development. A chronic corrosive lymphedema of the lower extremities can proceed to a elephantiasis (chronic lymphatic obstruction). W. bancrofti may cause a water break and scrotal elephantiasis. Other forms of chronic filariasis is caused by a rupture of lymphatic vessels or abnormal drainage of lymphatic fluid, which leads to formation of chyluria and Chylozelen. Lymphatic filariasis (elephantiasis) © Springer Science + Business Media var model = {thumbnailUrl: ‘/-/media/manual/professional/images/111_elephantiasis_slide_12_springer_high_de.jpg?la=de&thn=0&mw=350’ imageUrl: ‘/ – / media / ? manual / professional / images / 111_elephantiasis_slide_12_springer_high_de.jpg lang = en & thn = 0 ‘, title:’ lymphatic filariasis (elephantiasis) ‘description:’ ‘credits’ © Springer Science + Business Media’, hideCredits: false, hideTitle: false , hideFigure: false, hideDescription: true}; var panel = $ (MManual.utils.getCurrentScript ()) Closest ( ‘image-element-panel.’). ko.applyBindings (model, panel.get (0)); Lymphatic filariasis (range of severity of lymphedema) © Springer Science + Business Media var model = {thumbnailUrl: ‘/-/media/manual/professional/images/112_elephantiasis_slides_13a_b_c_d_joined_springer_high_de.jpg?la=de&thn=0&mw=350’ imageUrl: ‘/ ? – / media / manual / professional / images / 112_elephantiasis_slides_13a_b_c_d_joined_springer_high_de.jpg lang = en & thn = 0 ‘, title:’ lymphatic filariasis (range of severity of lymphedema) ‘description:’ ‘credits’ © Springer Science + Business Media’ , hideCredits: false, hideTitle: false, hideFigure: false, hideDescription: true}; var panel = $ (MManual.utils.getCurrentScript ()) Closest ( ‘image-element-panel.’). ko.applyBindings (model, panel.get (0)); Extralymphatic signs are for. As a chronic microscopic hematuria, proteinuria, and mild arthritis, which probably are all based on the deposition of immune complexes. A tropical pulmonary eosinophilia (TPE) is a rare manifestation and is associated with bronchospasm, transient pulmonary infiltrates, fever and discreet of marked eosinophilia associated. It has a limited most likely caused by hypersensitivity reactions to microfilariae. Chronic TPE may lead to pulmonary fibrosis. Diagnosis Microscopic examination of blood samples antigen test for W. bancrofti antibody tests The microscopic detection of microfilaria in the blood confirms the diagnosis. enriched by filtration or centrifugation, blood is more sensitive than the thickness drops. Blood samples should be taken at the time of highest Mikrofilariämie – at night in areas with endemic occurrence of W. bancrofti, but during the day on many Pacific islands to be infected with B. malayi and B. timori. Live adult worms can be made visible by ultrasound examination in dilated lymphatic vessels; their movements are called Filarientanz. Several blood tests are available: antigen detection: An immunochromatographic test in the quick format for W. bancrofti antigens Molecular Diagnostics: polymerase chain reaction assay for W. bancrofti and B. malayi antibody detection: Alternative enzyme immunoassay tests for antifilariale IgG1 and IgG4 patients with active filarial infections typically have elevated levels of antifilarialem IgG4 in blood. However, there is a serious antigenic cross-reactivity between filaria and other helminths, and a positive serologic test does not distinguish between past and current infection. Therapy diethylcarbamazine diethylcarbamazine (DEC) kills microfilariae and a variable proportion of adult worms. In the US, DEC is only available from the Centers of Disease Control and Prevention (CDC) for a laboratory confirmation of filariasis. It is usually DEC 2 mg / kg p.o. 3 times given daily for 12 days; 6 mg / kg p.o. once is an alternative. The therapies reduce microfilaremia in a similar way, but the effect of the one-day course on adult worms is less certain. The side effects with DEC are usually limited and depend on the blood on the number of microfilariae. The most common are dizziness, nausea, fever, headache and pain in muscles or joints, which are believed to be related to the release filarialer antigens. Before treatment, patients should be tested for coinfection with Loa loa and Onchocerca volvulus because DEC can cause these infections, severe reactions in patients. A single dose of albendazole 400 mg p.o. plus either ivermectin (200 ug / kg p.o.) in regions where also onchocerciasis is endemic, or DEC (6 mg / kg) in regions without onchocerciasis and Loiasis leads to a rapid reduction of the Mikrofilarienspiegels but Ivermectin can kill no adult worms. (Editor’s note: Cave Ivermectin is not approved in Germany in the medical area!) A variety of drug combinations and was -therapieplänen applied in the context of mass treatment programs. Also doxycycline was long-term (z. B. 100 mg p.o. 2 times daily for 4 to 8 weeks) was added. Doxycycline acts on the Wolbachia endosymbionts in filarial, resulting in the death of the worms. Acute attacks of ADL may subside spontaneously usually, however, antibiotics may be needed to control secondary bacterial infections. A chronic lymphedema requires meticulous skin care and the use of systemic antibiotics to treat secondary bacterial infections. These antibiotics can slow a elephantiasis or prevent. Whether treatment prevents DEC chronic lymphedema or relieves, remains controversial. Conservative measures such as an elastic bandaging the affected limb to reduce swelling. A surgical decompression with lymphatic venous shunts to improve lymphatic drainage provides some long-term benefits in extreme cases of elephantiasis. Massive hydroceles can also be treated surgically. A TPE responds to DEC 2 mg / kg p.o. 3 times daily for 12-21 days, but relapses can occur in up to 25% of patients and require additional treatment cycles. Prevention Avoiding mosquito bites in endemic areas is the best protection (eg., By use of diethyl toluamide [DEET], with permethrin-impregnated clothing and mosquito nets). Chemoprophylaxis with DEC or combinations antifilarieller substances (Ivermectin / albendazole, or ivermectin / DEC) can suppress Mikrofilariämie and thus reduce the transmission of the parasite by mosquitoes in endemic areas. DEC has even added in some endemic areas the salt. Important points lymphatic filariasis is transmitted by mosquitoes; infective larvae migrate to the lymphatic vessels where they develop into adult worms. Adult worms in the lymphatic vessels can cause inflammation, which can lead to chronic lymphocytic obstruction and in some patients elephantiasis. The diagnosis based on the microscopic detection of microfilaria in the filtered or centrifuged blood concentrates, which are taken at that time of day when the most commonly microfilaremia (varies depending on species). Tests on antigen, antibodies and parasite DNA serve as an alternative for the diagnosis by microscopy. Treatment is with diethylcarbamazine after reviewing a co-infection with Loa loa and Onchocerca volvulus.

Health Life Media Team

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