Sodium Citrate 1.8 mL Paed (Clear/Pale Blue Inner)
Sodium Citrate 1.0 mL Neonate (Pale Blue Top)
Sodium Citrate 2.7 mL (Solid Pale Blue Top)
A dedicated SST or sodium citrate tube will be required for this test. Accurate filling of sodium citrate tube essential. Specimens must be transported at room temperature to the Laboratory in a red specimen bag ASAP. (Maximum delay to testing laboratory must not exceed 2hrs) If difficulty collecting recommended amount please contactthe haematology laboratory on ext. 8500.
The hallmark of HIT is a fall in the platelet count between day 5 and 10 after starting heparin. A platelet count drop that exceeds 50% of a postoperative (high) value on day 1 of heparin treatment also strongly suggests HIT. Rapid platelet count falls may occur after previous exposure to heparin/LMWH. - The specificity of the anti-PF4/heparin ELISA is greatest when the OD value is > 1.0. The interpretation of a positive value between 0.4 and 1.0 is much less certain and is heavily dependent on clinical factors to determine if platelet-activating HIT antibodies are truly present. The incidence of false-positive ELISA results is highest in the 0.4-1.0 range and is due to non-pathogenic IgM and IgA antibodies or nonplatelet-activating antibodies.