From “Begumra:” Deficient factor in case of prolonged PT and PTT result that corrected with the addition of normal pooled plasma. All other screening tests are normal. I think it is factor V. Can you suggest that it is right? Hello, and thank you for your question. Assuming the patient is not on heparin or […]

From Vanessa Chan, Sick Kids Hospital, Toronto: Hi George, What is your opinion on the algorithm of tests when testing for lupus anticoagulant? If the mixing tests are normal, should we continue with a confirmatory test? The recent BJH guidelines say, “Mixing tests are a criterion for LA and improve the specificity. However, they introduce a dilution […]

From “Danagah” (originally posted February 23, 2012): Hi, George, have you seen the situation when, in the 1:1 immediate mix of a partial thromboplastin time (PTT) mixing study, the PTT is longer than the patient’s initial PTT? The patient does not appear to be on heparin (data to follow): Patient PTT: 39.0 sec Normal pool: 30.9 sec 1:1 […]