[Mansonella perstans filariasis]

Mansonella perstans filariasis is widely present in Africa and equatorial America and its pathogenicity has been recently reconsidered. Although M. perstans infection has been considered a minor filariasis, remaining asymptomatic in most of infected subjects, more recent studies have shown that M. perstans is capable of inducing a variety of clinical features, including angioedemas, swellings like the "Calabar swellings" of loiasis, pruritus, fever, headache, pain in bursae and/or joint synovia, or in serous cavities. It is likely that some of the pathological changes observed are induced by the immune response to the infection. Eosinophilia is present in many cases of infection. Moreover M. perstans filariasis is difficult to be treated. Effective treatment is lacking and there is no consensus on optimal therapeutic approach. The most commonly used drug is diethylcarbamazine (DEC) that is however often ineffective. Although other drugs have been tried (e.g. praziquantel, ivermectin), none has proven to be reliably and rapidly effective. Mebendazole seemed more active than DEC in eliminating the infection, with a comparable rate of overall responses. Thiabendazole evidenced a small, but significant activity against the infection. Combination treatments (DEC plus mebendazole) resulted in a significantly higher activity compared with the single drugs.