Bancroftian filariasis in children and adolescents: clinical-pathological observations in 22 cases from an endemic area.

In areas where bancroftian filariasis is endemic, the clinical manifestations of the disease, which are often very varied, appear most frequently during early adulthood or later. In consequence, very little attention, if any, has been given to the signs and symptoms of the disease in childhood. In an attempt to fill this gap, clinical and pathological observations were made, in Brazil, on 22 children (aged 2-15 years) who were infected with Wuchereria bancrofti. There was a predominance of lymph-node involvement. In all but three (14%) of the children (who had adult parasites in their intrascrotal lymphatic vessels), the adult worms were located in the afferent or efferent vessels of draining lymph nodes, predominantly in the inguinal region. None of the patients presented with distal lymphoedema, and the adenopathy was characterized by painless, localized, lymph-node enlargement, without signs of inflammation in the overlying skin. Histologically, the alterations in the lymphatic vessels and surrounding structures were similar to those described in adult patients, and depended essentially on adult-parasite viability. The localization of the adult worms in the paediatric cases was peculiar and distinct from that observed in adult patients, in whom the adult parasites are usually found in extra-nodal lymphatic vessels. In areas endemic for bancroftian filariasis, therefore, filarial infection should be considered as a possible cause of adenopathy. For the differential diagnosis of adenopathy in young patients from endemic areas, the authors recommend the use of ultrasound and other non-invasive diagnostic tools, as alternatives to excisional biopsies, which are often unnecessary in bancroftian filariasis.