Hemostatic mechanisms were investigated in two patients: one had deep vein thrombosis, the other one bled after a tooth extraction. Standard coagulation methods were used: Coagmate for P.T. and P.T.T., manual water bath methods for thrombin time, factor levels and circulating anticoagulants.
An 11 year old girl presented with a deep vein thrombosis of the left ileo-femoral junction. Her P.T.T. was prolonged 66"/30" with the presence of a circulating anticoagulant with Anti-factor XI activity. All other factors, fibrinogen and thrombin time were normal. A.N.A. was + 1/40; D.N.A. binding was + 1/40; complement (C4) was low. An Anti I was positive in a titer of 1/256. The patient was treated with anticoagulants for 6 months.
A 10 year old boy had prolonged bleeding following a deciduous tooth extraction. A spleen tip was the only pertinent physical finding. P.T. and P.T.T. were markedly prolonged (P.T. 16"/11"; P.T.T. 50"/30"). A circulating anticoagulant with Anti-factor XI and XII activity was detected. The patient’s clot dissolved completely at 4°C for 2 hours (while being stable for 48 hours at 37°C and 20°C). The patient had a + A.N.A., a + anti-D.N.A., and a positive direct Coombs’ with anti-N specificity. Hematuria, cylindruria, and proteinuria were also present. Following prednisone therapy, the circulating anticoagulant and the positive Coombs’ disappeared.
These cases illustrate that the lupus anticoagulant may be present with either thrombotic or hemorrhagic manifestations.