Here is a challenging technical question about the platelet neutralization procedure (PNP) for identification of lupus anticoagulant (LA) from Charlene Bierl MD, PhD Director of the Clinical Laboratory. Cooper University Hospital, Camden, NJ. Dr. Bieri’s question was originally addressed to Drs. Marisa B. Marques and Jill Adamski and to specialty technologists Laura Taylor and Patti Tichenor at the University of Alabama at Birmingham Hospital Department of Laboratory Medicine. Following is a lengthy dialogue:
From Charles Nakar, Indiana Hemophilia and Thrombosis Center: I would like your opinion on the laboratory results below regarding a patient who recently switched providers with a history of deep venous thrombosis due to May-Thurner syndrome and possible antiphospholipid antibody syndrome. He had positive anticardiolipin antibody (ACL) screens and a positive STA-clot (x1) during the acute event and recovery but full and separated quantitative ACLs were negative.
From Kathleen Doig, PhD, Professor, Biomedical Laboratory Diagnostics at Michigan State University. George – a question arose in our senior Medical Laboratory Science class today as students were constructing algorithms to investigate some case problems I gave them. Here’s the question: What is the platelet count for patients with thrombosis due to antiphospholipid syndrome (APA)?
From Jeanine Walenga, PhD, Loyola University Medical Center, Maywood, IL: When we perform the test for heparin-induced thrombocytopenia with thrombosis (HIT) using platelet aggregation, we use a reagent to remove heparin contaminant from the patient sample–ecteola cellulose. If there is a positive baseline (spontaneous aggregation with no heparin reagent added) we assume that there may be heparin in the patient sample. Se we treat the sample with ecteola cellulose, centrifuge, then retest the sample in the HIT aggregation assay. We just learned that the company Inotech Biosystems International, Inc. will not supply the ecteola cellulose until they find another manufacturer. Is there another source, preferably a clinical kit (not Sigma)? If Sigma is the only source, does someone have a clinical protocol? Thanks.
Here is an audio summary of Secretary of State Hillary Clinton’s Cerebral Sinus Venous Thrombosis episode by Samuel Goldhaber, MD