Clinical Information

This assay has not been validated for testing samples from newborns. Do not use samples that contain fluorescein. Fluorescein levels > 0.24 μg/mL may decrease results in this assay. Evidence suggests that patients undergoing retinal fluorescein angiography can retain amounts of fluorescein in the body for up to 48–72 hours post-treatment. In the cases of patients with renal insufficiency, including many diabetics, retention could be much longer. Such samples can produce falsely depressed values when tested with this assay, and should not be tested. For assays employing antibodies, the possibility exists for interference by human anti-animal antibodies (i.e., heterophile antibodies) in the patient sample. Patients who have been regularly exposed to animals or have received immunotherapy or diagnostic procedures utilizing immunoglobulins or immunoglobulin fragments may produce antibodies, (eg, HAMA), that interfere with immunoassays. This may falsely elevate or falsely decrease the results.