title: Screening of patients with idiopathic venous thromboembolism for paroxysmal nocturnal hemoglobinuria clones.
abstract: Paroxysmal nocturnal hemoglobinuria (PNH) is an uncommon disorder characterized by hemolysis, thrombosis and marrow failure. Whereas venous and arterial thrombosis is a very common symptom of the disease, the frequency of PNH clones in patients with unexplained venous thromboembolism, including deep vein thrombosis and pulmonary embolism, has not been studied. We conducted a cross sectional study evaluating the presence of PNH clones in patients with prevalent venous thromboembolism using a high sensitivity flow cytometry assay for erythrocytes and neutrophils. Among the 388 patients enrolled in the study one patient had a detectable PNH clone of 0.02% in the neutrophil population (0.26%; 95% CI 0.05 to 1.45) and no detectable erythrocyte clone. We conclude that the presence of PNH clones in patients with idiopathic venous thrombosis is rare. Screening for PNH clones among VTE patients might be better reserved for patients with signs of hemolysis.
authors.affiliation: Department of Medicine, Division of Hematology, University of Western Ontario, London, Ontario, Canada; Department of Epidemiology and Biostatistics, University of Western Ontario, London, Ontario, Canada. Electronic address: alejandro.lazolangner@lhsc.on.ca.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Lazo-Langner
authors.affiliation: Department of Medicine, Division of Hematology, University of Western Ontario, London, Ontario, Canada.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Kovacs
authors.affiliation: Pathology and Laboratory Medicine, London Health Sciences Centre, London Ontario, Canada.
authors.forename: Ben
authors.initials: B
authors.lastname: Hedley
authors.affiliation: Department of Medicine, Division of Hematology, University of Western Ontario, London, Ontario, Canada.
authors.forename: Fatimah
authors.initials: F
authors.lastname: Al-Ani
authors.affiliation: Pathology and Laboratory Medicine, London Health Sciences Centre, London Ontario, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Keeney
authors.affiliation: Department of Medicine, Division of Hematology, University of Western Ontario, London, Ontario, Canada; Department of Epidemiology and Biostatistics, University of Western Ontario, London, Ontario, Canada.
authors.forename: Martha L
authors.initials: ML
authors.lastname: Louzada
authors.affiliation: Department of Medicine, Division of Hematology, University of Western Ontario, London, Ontario, Canada.
authors.forename: Ian
authors.initials: I
authors.lastname: Chin-Yee
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D004912:Erythrocytes / Q000166:cytology; D005260:Female; D005434:Flow Cytometry; D006457:Hemoglobinuria, Paroxysmal / Q000175:diagnosis*; D006461:Hemolysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000166:cytology; D015995:Prevalence; D054556:Venous Thromboembolism / Q000175:diagnosis*
keywords: Paroxysmal nocturnal hemoglobinuria; Venous thromboembolism