Shenoy RK et al. (2000) Ann Trop Med Parasitol "Apparent failure of ultrasonography to detect adult worms of Brugia malayi."

Kumaraswami V, John A, Shenoy RK, Hameed S, Suma TK

[Ann Trop Med Parasitol, 2000]

Adult worms of Wuchereria bancrofti, or rather their characteristic movements (the 'filarial dance'), can now be detected in the scrotal lymphatics of microfilaraemic males, using ultrasonography. This ability has been used to delineate the lymphatic pathology of bancroftian filariasis, guide the surgical removal of the adult worms and, most importantly, assess the macrofilaricidal effects of antifilarial drugs. In the present study, the first report of the use of ultrasonography in brugian filariasis, 22 men (aged 18-62 years) with 60-2972 (median = 370) Brugia malayi microfilariae/ml blood were subjected to ultrasonography using a linear, 7.5-MHz probe. In addition, four other men (aged 19-35 years), with W. bancrofti microfilaraemia [28-524 (median = 234) microfilariae/ml], were similarly examined. Adult worms were not detectable in any of the patients with B. malayi parasitaemia but were detected in the scrotal lymphatics of two of the four individuals with W. bancrofti infection. The reasons for the failure to detect adult B. malayi and the limitations of ultrasound as a screening tool are examined. The results highlight the differences between the two species that cause most lymphatic filariasis and the need for rapid development of tools that can be used for the control of brugian lymphatic filariasis.

Shenoy RK et al. (2007) Ann Trop Med Parasitol "Doppler ultrasonography reveals adult-worm nests in the lymph vessels of children with brugian filariasis."

Shenoy RK, Suma TK, Ramesh C, Padma S, Abhilash G, Rahmah N, Kumaraswami V

[Ann Trop Med Parasitol, 2007]

Although ultrasonography has allowed 'nests' of live adult worms and dilated lymphatics to be detected in the early stages of infection with Wuchereria bancrofti, previous attempts to locate such adult-worm nests in brugian filariasis have been unsuccessful. In this study, the successful location of live adult Brugia malayi parasites, in the lymphatics of the axilla, thigh, epitrochlear region and/or popliteal fossa of children aged 3-15 years, is described for the first time. The 'filarial dance sign' (FDS), which indicates the presence of live adult worms, was observed in six children with microfilaraemia and in eight children who, though amicrofilaraemic, either had experienced an episode of lymphoedema (one) or were only positive for antifilarial IgG4 antibodies (seven). In bancroftian infection, the adult-worm nests have mostly been seen in asymptomatic but microfilaraemic subjects. The suspected worm nests, 18 in the 14 children, were all confirmed using colour-power and pulse-wave Doppler examinations. The worm nests were distinctly smaller and the wriggling movements were less rapid and less conspicuous than those seen in bancroftian filariasis. The importance of these findings in the management and control of lymphatic filariasis is discussed.

Shenoy RK et al. (2009) J Commun Dis "Relevance of anti-BmR1 IgG4 antibodies in children from an area endemic for Brugia malayi infection in Kerala, India."

Thaslim AX, Suma TK, Shenoy RK, Rahmah N, Gopu RB, Kumaraswami V

[J Commun Dis, 2009]

Brugian filariasis prevalent mostly in South-East Asian countries including India contributes to a small but significant proportion of the socioeconomic burden due to lymphatic filariasis. Along with bancroftian filariasis, brugian filariasis has been targeted for elimination globally. The lack of a reliable daytime diagnostic test has been seen as an important barrier to the successful implementation and monitoring of elimination programmes in brugia endemic areas. We evaluated an anti-BmRI-IgG4 antibody test namely, 'Brugia Rapid' in a large study meant to understand the clinical and pathological manifestations of brugian filariasis in children. We found the test superior to traditional night blood screening for microfilaraemia. Although an antibody detection test, we found it to be a reliable indicator of brugian infection. Among the 100 children studied extensively, 94% of the microfilaraemics, 86% of those showing filarial dance sign indicating presence of, live adult worms and 78% having abnormal lymphatics on lymphoscintigraphy were IgG4 positive. Coupled with its advantages like ease of use any time of the day, high sensitivity and specificity, this test may be the ideal tool to assist programme managers in their efforts to eliminate lymphatic filariasis where brugian infections are found.

Shenoy RK et al. (1998) Ann Trop Med Parasitol "Prevention of acute adenolymphangitis in brugian filariasis: comparison of the efficacy of ivermectin and diethylcarbamazine, each combined with local treatment of the affected limb."

Shenoy RK, Kumaraswami V, Suma TK, Rajan K

[Ann Trop Med Parasitol, 1998]

Acute attacks of adenolymphangitis (ADL) not only force patients with lymphatic filariasis to seek medical attention but also hasten the progression of filarial oedema. Patients with filariasis-associated ADL are currently treated with repeated courses of the antifilarial drug diethylcarbamazine (DEC), with or without antibiotics and anti-inflammatory agents. In this double-blind, placebo-controlled study, the efficacy of local treatment of the affected limb combined with repeated doses of ivermectin or DEC, in preventing the occurrence of ADL in Brugia malayi lymphatic filariasis, was examined. Overall, 120 patients who had each had at least two ADL attacks in the previous year were each admitted to the study at the time of an ongoing episode of ADL. The patients were randomly allocated to receive 12, monthly treatments of ivermectin (400 micrograms/kg), DEC (10 mg/kg) or placebo, in addition to local care of the affected limbs. There was a significant reduction in the frequency of ADL attacks in each of the three groups during the 2-year study period (P < 0.001 for each comparison). Most importantly, there were no significant differences in frequency of attacks between the three groups, either at the end of the treatment phase or at the end of the post-treatment phase (P > 0.15 for each comparison), suggesting that foot care combined with appropriate use of local antibiotics or antifungals is adequate to reduce the number of ADL attacks. The implications of these observations for planning morbidity control in lymphatic filariasis are discussed.

Shenoy RK et al. (2007) Ann Trop Med Parasitol "Preliminary findings from a cross-sectional study on lymphatic filariasis in children, in an area of India endemic for Brugia malayi infection."

Dhananjayan G, Ramesh C, Shenoy RK, Suma TK, Kumaraswami V, Padma S, Rahmah N, Abhilash G

[Ann Trop Med Parasitol, 2007]

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.

Shenoy RK et al. (2000) Ann Trop Med Parasitol "Two-year follow-up of the microfilaraemia of asymptomatic brugian filariasis, after treatment with two, annual, single doses of ivermectin, diethylcarbamazine and albendazole, in various combinations."

Kumaraswami V, Shenoy RK, Babu BS, Suma TK, John A

[Ann Trop Med Parasitol, 2000]

Repeated, single, oral doses of combinations of ivermectin, diethylcarbamazine (DEC) or albendazole are recognized as important tools for parasite control in lymphatic filariasis. In order to assess the effects of re-treatment using these combinations in Brugia malayi infections, 40 asymptomatic microfilaraemics were re-treated at the end of the first year, with an additional, single, dose of the combination they had previously received. They were then followed-up for another year. The subjects, of both sexes and aged 14-70 years, each received a two-drug combination: ivermectin (200 micrograms/kg) with DEC (6 mg/kg); ivermectin (200 micrograms/kg) with albendazole (400 mg); or DEC (6 mg/kg) with albendazole (400 mg). The kinetics of microfilarial clearance were similar to that seen during the first treatment, the members of the two groups given DEC having less intense microfilaraemias, 1 year after the re-treatment, than those given ivermectin with albendazole (P < 0.001 for each comparison). At this time, the two DEC groups also had a higher proportion of amicrofilaraemic individuals (22 of 26) than the ivermectin + albendazole group (three of nine). There were fewer adverse reactions in all the groups after re-treatment than seen after the first treatment. In countries such as India, where there is no co-endemicity of onchocerciasis or loiasis, the options for control programmes in areas where brugian filariasis is endemic are DEC alone or DEC in combination with ivermectin or albendazole. Where there is no access to ivermectin, transmission control must be based on DEC alone or in combination with albendazole.

Rahmah N et al. Trans R Soc Trop Med Hyg "Specificity and sensitivity of a rapid dipstick test (Brugia Rapid) in the detection of Brugia malayi infection."

Chan BT, Suharni M, Kumaraswami V, Hakim SL, Anuar AK, Rahmah N, Taniawati S, Shenoy RK, RAMACHANDRAN CP, Lim BH, Hayati MI

[Trans R Soc Trop Med Hyg]

A total of 753 serum samples from 6 institutions in 3 countries (Malaysia, Indonesia and India) were used to evaluate an immunochromatographic rapid dipstick test, Brugia Rapid, for diagnosis of Brugia malayi infection. The samples comprised sera from 207 microfilaria-positive individuals and 546 individuals from filaria non-endemic areas. The latter consisted of 70 individuals with soil-transmitted helminth infections, 68 with other helminth infections, 238 with protozoan infections, 12 with bacterial and viral infections and 158 healthy individuals. The dipstick is prepared with a goat anti-mouse antibody control line and a B. malayi recombinant-antigen test line. First, the dipstick is dipped into a well containing diluted patient serum, thus allowing specific anti-filarial antibody in the serum to react with the recombinant antigen. Then the dipstick is placed into an adjacent well containing reconstituted anti-human IgG4-gold. After 10 min, development of 2 red-purplish lines denotes a positive result and one line indicates a negative reaction. The overall results of the evaluation showed 97% sensitivity, 99% specificity, 97% positive predictive value and 99% negative predictive value. Brugia Rapid is thus a promising diagnostic tool for detection of B. malayi infection, and would be especially useful for the brugian filariasis elimination programme.