Filaria, Blood
Use
Filarial infections are caused by parasitic nematodes that result in significant human morbidity in tropical regions. Detecting microfilariae in peripheral blood is crucial for diagnosing infections caused by species such as Wuchereria bancrofti, Brugia malayi, and Loa loa. These organisms can lead to conditions like lymphatic filariasis and other systemic symptoms, including fever, angioedema, and musculoskeletal pain. The detection of microfilariae in the blood, using techniques like concentration methods, enhances sensitivity and allows for timely treatment and intervention.
Special Instructions
Blood collection must be timed according to the periodicity of the microfilariae. For lymphatic filariasis agents, blood should be collected between 10 p.m. and 2 a.m., while for Loa loa, collection should occur between 10 a.m. and 2 p.m. If not ordering electronically, complete and submit a Microbiology Test Request (T244) with the specimen.
Limitations
This test cannot detect microfilariae found primarily in the skin, such as Onchocerca volvulus and Mansonella streptocerca. Blood films can miss microfilariae if they are scarce, necessitating the use of concentration methods for improved detection. Multiple smears may be required to confirm diagnosis, and repeat specimens should be collected every 8 to 12 hours over 2 to 3 days before ruling out infection.
FDA ApprovedNew York Approved
Methodology
Microscope
Biomarkers
LOINC Codes
- 10662-5
- 10662-5
Result Turnaround Time
1-4 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
2.7 mL
Minimum Volume
2 mL
Container
Light-blue top (3.2% sodium citrate)
Collection Instructions
Collect blood during specified times for optimal detection. For lymphatic filariasis, collect between 10 p.m. and 2 a.m.; for Loa loa, collect between 10 a.m. and 2 p.m.
Causes for Rejection
All specimens are evaluated for test suitability.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 72 hours |