Filariasis, bancroftian

Two forms of lymphatic filariasis are found in India. The Bancroftian form is the most common and accounts for more than 90% of the disease whereas Bmgian filariasis accounts for the rest. In a study carried out in India (6) in 40 patients with Wuchereria Bancwfti filariasis treated with single oral doses, all of the dose levels chosen (25, 50, 100, and 200 mg/kg) were efficacious in clearing microfilariae from the blood of all patients treated. However, after three months some microfilaria recurred in the blood of most patients (Table 5). Further studies are planned and some are underway using different doses and regimens. Ivermectin still appears to hold promise as a new treatment for lymphatic filariasis. 

Freedman D.O., Nutman, T.B. and Ottensen, E.A. (1989) Protective immunity in bancroftian filariasis. Selective recognition of a 43-kDa larval stage antigen by infection-free individuals in an endemic area. Journal of Clinical Investigation 83, 14-22. 

E. TPE is caused by microfilariae in the lungs and hyperimmune responsiveness to bancroftian or malayan filariasis. Paroxysmal respiratory symptoms may fluctuate in severity. Eosinophilia, almost always present, is usually very high, and the absence of microfilariae in the blood does not rule out TPE. A presumptive clinical diagnosis can be made by response to therapy without a lung biopsy. Diethylcarbamazine for 14 days is an effective therapy that can be repeated if symptoms persist. The role of ivermectin in TPE has not been established. 

Diethylcarbamazine may also be used for chemoprophylaxis (300 mg weekly or 300 mg on 3 successive days each month for loiasis 50 mg monthly for bancroftian and Malayan filariasis). 

Ramzy RM et al Effect of yearly mass drug administration with diethylcarbamazine and albendazole on bancroftian filariasis in Egypt A comprehensive assessment. Lancet 2006 367 992. [PMID 16564361]... 

Mass treatment with diethylcarbamazine is a key measure for control of the transmission of bancroftian filariasis. However, severe adverse reactions can occur in patients with onchocerciasis treated with high doses of diethylcarbamazine, which may hmit the prospects for the use of common salt medicated with diethylcarbamazine in many parts of Africa. However, the daily dose of diethylcarbamazine-medicated salt is considerably lower than that of conventional tablets (25-50 mg od for the first 1 or 2 days followed by 100 mg bd for 5-7 days). 

Reuben R, Rajendran R, Sunish IP, Mani TR, Tewari SC, Hiriyan J, Gaj anana A. Annual single-dose diethylcarbamazine plus ivermectin for control of bancroftian filariasis comparative efficacy with and without vector control. Ann Trop Med Parasitol 2001 95(4) 361-78. 

As antihehninthic drugs go, ivermectin can be considered a reasonably safe drug, and it is generally better tolerated than diethylcarbamazine. Clinical experience has often shown relatively little toxicity, although mild adverse effects, presumably due to the kilting of the microfilariae, involve at least one-third of patients some work has suggested that neutrophil activation may play a role in the development of these reactions (1). It has also been well tolerated in combinations, for example when given with albendazole in order to kill adult worms (which cannot be achieved with ivermectin alone) or with diethylcarbamazine for bancroftian filariasis (SEDA-20, 281). 

Early-stage elephantiasis caused by bancroftian filariasis in a 27-year-old traveller was treated with a single-dose oral combination of ivermectin 24 mg plus albendazole 400 mg, followed by albendazole 800 mg for 21 days (14). To avoid a severe Mazzotti-like reaction, he was given oral glucocorticoids and antihistamines for 3 days. He had a transient rash, pruritus, and mild hypotension on the days after the initial treatment, but otherwise remained well and the swelling subsided. Within 1 month he was free of symptoms. At the last follow-up examination, 3 years after treatment, there was no clinical or laboratory evidence of relapse. The authors thought that this type of treatment should be evaluated on a wider scale, given the minimal adverse events and apparent therapeutic efficacy. 

The efficacy of annual mass chemotherapy with a combination of diethylcarbamazine and ivermectin on bancroftian filariasis in rural southern India has been studied, as has the supplementary role of controlling the vector mosquito Culex quinquefasciatus (15). Nine... 

Moulia-Pelat JP, Nguyen LN, Glaziou P, Chanteau S, Gay VM, Martin PM, Cartel JL. Safety trial of single-dose treatments with a combination of ivermectin and diethylcarbamazine in bancroftian filariasis. Trop Med Parasitol 1993 44(2) 79-82. 

The efficacy of ivermectin for human onchocerciasis was established in the 1980s and is summarized in this chapter briefly. Clinical study of ivermectin in human strongyloidiasis has not yet been completed. Here we describe the efficacy of ivermectin for human strongyloidiasis as observed in our institution during the past decade. Furthermore, we would like to describe the combination therapy with ivermectin and albendazole for bancroftian filariasis and also the efficacy of ivermectin in the treatment of human scabies. 

Combined treatment with ivermectin and albendazole for bancroftian filariasis was more effective than treatment with ivermectin alone. In tropical countries where bancroftian filariasis is endemic, infection with intestinal helminths is also an important public health concern. Additional benefits of this combination are its potent, broad-spectrum activity against intestinal helminths and potential relative safety. 

Freedman, D. O. Berry, R. S. Rapid diagnosis of Bancroftian filariasis by acridine orange staining of centrifuged parasites. Am. J. Prop. Med. Hyg. 1992, 47, 787-793. 

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