Antifilarial drugs, in the doses employed in mass drug administrations by the Global Programme to Eliminate Lymphatic Filariasis, reverse lymphatic pathology in children with Brugia malayi infection.

Lymphatic filariasis is increasingly viewed as the result of an infection that is often acquired in childhood. The lymphatic pathology that occurs in the disease is generally believed to be irreversible. In a recent study in India, Doppler ultrasonography and lymphoscintigraphy were used to explore subclinical pathology in 100 children from an area endemic for Brugia malayi infection. All the children investigated showed some evidence of current or previous filarial infection. Some were microfilaraemic but asymptomatic, some were amicrofilaraemic but had filarial disease or a past history of microfilaraemia and/or filarial disease, and the rest, though amicrofilaraemic, asymptomatic and without any history of microfilaraemia or filarial disease, were seropositive for antifilarial IgG(4) antibodies. All the children were treated every 6 months, with a single combined dose of diethylcarbamazine (6 mg/kg) and albendazole (400 mg), and followed up for 24 months. By the end of this period all but one of the children were amicrofilaraemic and the 'filarial dance sign' could not be detected in any of the 14 children who had initially been found positive for this sign. Although lymphoscintigraphy revealed lymph-node and lymph-vessel damage in 82% of the children at enrolment, in about 67% of the children this pathology was markedly reduced by the 24-month follow-up. These results indicate that the drug regimens used in the mass drug administrations run by the Global Programme to Eliminate Lymphatic Filariasis are capable of reversing subclinical lymphatic damage and can provide benefits other than interruption of transmission in endemic areas. The implications of these findings are presented and discussed.

Lymphoscintigraphic evidence of lymph vessel dilation in the limbs of children with Brugia malayi infection.

Lymphatic filariasis (LF) is targeted for global elimination by the year 2020. It was earlier believed that LF is mostly a disease of adults. Recent studies indicate that in endemic countries filarial infection starts mostly in childhood even though the disease manifestations occur much later in life. The initial damage to the lymph vessels where the adult worms are lodged is dilation, thought to be irreversible even with treatment. Most of these studies relate to bancroftian filariasis. Studies that address this early pathology in brugian filariasis in humans are scarce. We report here for the first time, the lymphatic abnormalities seen on lymphoscintigraphy (LSG) in children with Brugia malayi filariasis. LSG was performed in 100 children aged between 3-15 years, who were enrolled in the study either because they were microfilaremic; had present or past filarial disease or were positive for antifilarial IgG4 antibodies. Inguinal and axillary lymph nodes were imaged in most children. Dilated lymph vessels were visualized in 80 children and this pathology was evenly distributed in all the three study groups. Lymph vessels dilation was seen even in three year old children. The implications of these findings for management of LF and control programmes are discussed.

Preliminary findings from a cross-sectional study on lymphatic filariasis in children, in an area of India endemic for Brugia malayi infection.

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.

MICROSOMAL AND THYROGLOBULIN ANTIBODIES IN THYROID DISORDERS.

Eighty patients with various thyroid disorders and 20 controls were investigated to determine antibodies against thyroglobulin and microsomal antigens by haemagglutination and immunofluorescent techniques. They were also tested for immunoglobulin profile by radial immunodiffusion methods. Patients with Hashimoto's disease, idiopathic hypothyroidism, and Grave's disease showed significant elevations of IgG. None of the patients with toxic nodular goitre or thyroid adenoma showed any thyroid antibodies while 69.2% patients with Grave's disease, 16% with euthyroid goitre, 58.3% with hypothyroidism and all the patients with Hashimoto's disease had microsomal antibodies by immunofluorescent test. Similarly, all the cases of Hashimoto's disease, 41.6% of those with hypothyroidism, 30% of Grave's disease patients and none of the patients with toxic nodule or thyroid adenoma had thyroglobulin antibodies by haemaglutination test. Evaluation for auto-antibodies may aid the clinician in the overall assessment of various thyroid disorders.

Fine needle aspiration biopsy--a critical investigation in thyrotoxicosis.

Four hundred and fifty two patients having clinical features of thyrotoxicosis have been studied for their hormonal (T4, T3 and TSH) content, I131 uptake levels and FNAB at repeated intervals. Four hundred and twenty seven had presented with diffuse enlargement and rest 25 cases with nodular enlargements. Of the primary hyperthyroidism cases 342 (82.4%) were of Grave's disease without exophthalmos and 73 (17.6%) with exophthalmos. T4, T3 and I131 uptake levels have correlated well with the degree of morphological changes as observed on FNAB. Degree of nuclear pleomorphism has correlated well with the duration of disease. Critical evaluation of morphological changes on FNAB has been done in all cases of primary hyperthyroidism being treated with neomercazole and radioactive iodine therapy. Treatment with neomercazole had shown, good correlation between time lag and the retrogressive changes. This was not so in cases treated with radioactive iodine therapy. Various known complications of radioactive treatment e.g. development of hypothyroidism, refractory and recurrent hyperthyroidism, exacerbation of the disease, radiation thyroiditis, and severe degree of dysplastic changes could be demonstrated in some cases on serial aspirations.