Preliminary findings from a cross-sectional study on lymphatic filariasis in children, in an area of India endemic forBrugia malayiinfection

Abstract

As the more obvious clinical manifestations of the disease are very uncommon in children, lymphatic filariasis has been considered to be primarily a disease of adults. In many recent reports, however, there is evidence indicating not only that filarial infection is commonly acquired in childhood but also that many infected children already have irreversible damage to their lymphatics. The preliminary results of a cross-sectional study on the patterns of Brugia-attributable pathology in 7934 children (aged 3-15 years) who live in an area of India with endemic B. malayi infection confirm these trends. The children were screened for microfilaraemia, evidence of filarial disease, and the presence of antifilarial IgG(4) antibodies. One hundred children who were microfilaraemic but asymptomatic (32), with filarial disease or an history of such disease or microfilaraemia (29) or amicrofilaraemic and asymptomatic but seropositive for antifilarial IgG(4) (39) were investigated further. They were given detailed clinical examinations, their levels of microfilaraemia were evaluated (by counting microfilariae filtered out of blood samples), their lymphatics were explored by Doppler sonography, and their limbs were checked by lymphoscintigraphy. The 'filarial dance sign', which indicates the presence of live adult worms, was detected by sonography in 14 children (apparently the first time this sign has been observed in brugian filariasis). Lymphoscintigraphy revealed dilated lymphatic channels in the limbs of 80 of the children. At the end of the study, each of the 100 hospitalized children was treated with a single combined dose of diethylcarbamazine and albendazole; the aim is to follow-up the treated children every 6 months for 3 years. Even these preliminary results have important implications for filariasis-control programmes and emphasise the need for disability-alleviation efforts among children as well as adults.

Clinical and Pathological Aspects of Filarial Lymphedema and Its Management

“…This has also been confirmed by prevalence studies on microfilaremia and filarial antigenemia in children [34,35]. Existence of live adult filarial worms has been shown on Doppler sonography and lymphatic dilatation by lymphoscintigraphy in children aged 3-15 yr [13,15]. This lymphatic pathology in infected children, since it is known to persist, might pave way for future development of disease manifestations.…”

“…This has been demonstrated in subjects who are clinically asymptomatic except for presence of microfilariae (mf) in blood, by ultrasound examination of the lymphatics of the spermatic cord; lymphoscintigraphy of the limbs and by direct examination of lymph vessels resected by surgery [9,14]. Dilatation of the lymph vessels has been demonstrated by lymphoscintigraphy even in children with brugian filarial infection [15]. It is believed that this damage to lymph vessels is caused by the adult parasites through mediators produced by them, which cause vessel dilatation or inhibit contractility [16].…”

Heightened Measures of Immune Complex and Complement Function and Immune Complex–Mediated Granulocyte Activation in Human Lymphatic Filariasis

“…For example, lymphoscintigraphy studies have shown that asymptomatic infected persons have subclinical disease with considerable structural abnormalities and aberrant lymph flow. [40][41][42] In addition, subclinical lymphatic dysfunction was detectable in LF-infected children despite the absence of clinically evident lymphedema. 43 Therefore, CIC in LF constitutes a complex network modulating the levels of complement fragments, granular proteins, and cytokines/chemokines, which turn profoundly influences disease manifestations in this infection.…”

Lymphatic filariasis in children: Clinical features, infection burdens and future prospects for elimination

“…This was done by intradermally injecting 0·5 ml of a solution containing 2 μCi of Tc 99m -tagged sulphur colloid into the first web spaces of both feet and hands and the lymphatics were imaged using gamma camera (Shenoy et al 2007b). Dilated lymphatic channels were seen in 80 of the 100 children.…”