Mak JW
International Medical University, Sesama Centre, Plaza Komanwel, Bukit Jalil, 57000 Kuala Lumpur, Malaysia
Correspondence: Dr Mak JW.· e-mail:
CITATION: Mak J.W. Diagnosis of lymphatic filariasis: some issues and challenges. International Medical Research Journal. 2001;5(1):43–8.
ABSTRACT
Diagnosis of filariasis,s is based on clinical suspicion and confirmed by laboratory,y evidence of infection with the parasite. Detection of infection is needed in control programmes and for management of the individual patient. As the clinical spectrum of lymphatic filariasis is wide different laboratory diagnostic techniques may be required to detect different phases of the infection. Filariasis control programmes have rather specific requirements; we need to know the geographical distribution of endemic area and tests are mainly needed to detect microfilaraemics and intensity of transmission. Control programmes based on selective or mass treatment of endemic populations require direct laboratory evidence of active infection. This may be achieved through demonstration of microfilaraemia or antigenaemia. Detection of infection in mosquitoes especially demonstration of the parasite infective stage in mosquitoes is needed to identify vectors and determine vectorial capacities. [In the clinical setting, a greater range of techniques may be useful in assessing the stage of the infection or for differential diagnosis. For example. laboratory requirements for the diagnosis of tropical pulmonary eosinophilia and other forms of occult filariasis are different from that for detection of microfilaraemic in the patient presenting with acute adenolymphangitis. Molecular approaches to diagnosis including the production of reagents for diagnostic assays have resulted in a variety of different assays for detection and evaluation of infection status. Many of these assays are extremely sensitive and specific but are not easily adapted to field use. Other assays, especially some commercial kits are convenient to use and can rapidly detect infection at the point of care. The challenge is to march the sensitivity and specificity of the assay to the appropriate situation and not to be overwhelmed by the perceived need to follow. blindly practices useful in other health scenario. II is important to determine the appropriate assays for the different purposes needed by healthcare workers in control programmes and in clinical practice. Perhaps it is opportune for us to produce practice guidelines on what tests are appropriate in the different health situations. Outcomes research based on cost effectiveness, client satisfaction, efficiency and accuracy. etc. utilising meta-analyses of data from health and medical practices as well as clinical trials can assist and should be carried out.
KEYWORDS: clinical diagnosis, molecular assays, rapid diagnostic tests, outcomes research
