Indirect Immunofluorescent Assay (IFA) – IgG

Detection of IgG antibodies to Anaplasma phagocytophilum by IFA.

Fresh human serum. Minimum volume of serum required - 0.5 mL. Hyperlipemic, hemolysed or contaminated sera may yield erroneous results.

Collect blood in serum separator tubes.

Transfer an aliquot of serum to a 1.5 ml screw-top vial with O-ring (Sarstedt vial). Store specimens refrigerated up to 5 days or store frozen until shipped for testing. Ship frozen on dry or wet ice.

Shipping of specimens shall be done by a TDG certified individual in accordance with TDG regulations. For additional information regarding classification of specimens for the purposes of shipping, consult either Part 2 Appendix 3 of the TDG Regulations or section 3.6.2 of the IATA Dangerous Goods Regulations as applicable.

Appropriate clinical symptoms with potential exposure to blacklegged ticks.

Completed requisition for Tick-borne Disease Diagnostic Testing. If possible, include the clinical history and lab results performed at local or provincial laboratories.

Specimens may be subject to rejection if they are not the appropriate sample type, have insufficient volume, or are not accompanied by relevant patient information.

Commerical IFA kit. This is a semi-quantitative test for the detection of IgG antibodies to A. phagocytophilum. A four-fold or greater increase in IgG titre between two serum samples drawn 1 to 2 weeks apart and tested in parallel is considered presumptive evidence of a recent or current infection with A. phagocytophilum. An IgG endpoint greater than 1:64 alone should not be relied on for a diagnosis of A. phagocytophilum infection.

Initiation of antibiotic treatment prior to testing may result in decreased antibody production which will affect the outcome of serological testing. However, if infection with A. phagocytophilum is suspected based on clinical symptoms, treatment should be initiated.

21 calendar days.

1. Bakker, J.S., Dumler, J.S. 2008. Human Granulocytic Anaplasmosis. Infect. Dis. Clin. N. Am. 22:433-448.