What are the key clinical features to consider when diagnosing lymphatic filariasis in a patient presenting with lymphoedema?

When diagnosing lymphatic filariasis in a patient presenting with lymphoedema, the key clinical features to consider include the presence of chronic, progressive swelling typically affecting the lower limbs, which may be unilateral or bilateral. The swelling is often non-pitting and associated with thickening of the skin and subcutaneous tissues, leading to elephantiasis in advanced cases. Patients may report a history of recurrent episodes of acute adenolymphangitis characterized by fever, chills, and painful inflammation of the lymph nodes and lymphatic vessels. Palpable lymphadenopathy and lymphangitis are common early signs. Additionally, the presence of hydrocele in males is a frequent manifestation. A history of residence or travel to endemic areas is crucial for clinical suspicion. Laboratory confirmation may include detection of microfilariae in blood samples, typically collected at night, or antigen detection tests. Importantly, the clinical presentation often develops years after initial infection, reflecting the chronic lymphatic damage caused by the filarial parasites Witt & Ottesen 2001Shenoy & Bockarie 2011. The diagnosis should also consider differential causes of lymphoedema, but the combination of endemic exposure, characteristic lymphoedema distribution, recurrent inflammatory episodes, and supportive laboratory findings strongly suggests lymphatic filariasis NICE NG101.