This week we would like to share with you a tropical disease case. An elderly gentleman presented to Kivunge Hospital with a very swollen right foot. He had already been treated for cellulitis (skin infection) with antibiotics but had little improvement. Examining his foot, it was grossly swollen compared to the left but didn’t show other typical signs of infection (warmth, redness, tenderness).
The clinical officer who saw him first in outpatients had queried filariasis, a disease caused by a parasite, and the team in inpatients agreed. Therefore we referred him to a special unit in town dedicated to the treatment of neglected tropical diseases such as filariasis. The patient returned to Kivunge the next day with confirmation of filariasis and the correct treatment.
This case taught us the importance of thinking outside of the usual causes we are used to in Europe and considering tropical diseases in our differential diagnosis as well!
Filariasis is a tropical disease caused by a microscopic parasitic worm, transmitted via mosquito bites. The larvae enter the body and migrate to lymphatic vessels where they grow into adult worms. The worms then disrupt the function of the lymphatic system, causing the clinical features of lymphedema (tissue swelling), elephantiasis of limbs and hydrocele (scrotal swelling). During their lifetime the adult worms produce millions of larvae which circulate in the bloodstream and infect mosquitoes, therefore beginning the cycle again.
Filariasis is a neglected tropical disease, meaning it is endemic only in low income countries. According to the WHO, 852 million people in 52 countries worldwide remain threatened by lymphatic filariasis. The painful and physically disabling manifestations of the disease result in massive socioeconomic burdens. This disease can (and has been) successfully eliminated in fourteen countries with a mass drug administration programme - giving an annual dose of medicine to an entire at-risk population. Unfortunately Tanzania is one of the countries where preventative chemotherapy is still required but has not been delivered.
More awareness is needed around diseases like filariasis in order to accomplish the WHO goal of eradication by 2020.