Comparison of several activated partial thromboplastin time methods

Coagulation abnormalities in type 1 Gaucher disease in children

Gaucher disease is the most prevalent inherited lysosomal storage disorder caused by deficiency of beta-glucocerebrosidase enzyme. Clinically, 3 forms of Gaucher disease are recognized, of which type 1 is the mild to moderately severe, slowly progressive, nonneuropathic form. Bleeding disorders in Gaucher disease are believed to be due to thrombocytopenia but there may be additional factors that influence coagulation and fibrinolysis in Gaucher disease patients. The aim of the present work was to study some coagulation parameters in the Egyptian children with type 1 Gaucher disease. Five newly diagnosed patients and another 5 patients on enzyme replacement therapy (ERT) were enrolled in the study. Their coagulation profile, including coagulation factors, was evaluated. The results showed that in newly diagnosed cases factors II and VII were deficient in 40%, factor V was deficient in 20%, and all the cases had low levels of serum fibrinogen. In patients on ERT, factors VII and VIII were deficient in 60%, factor XI was deficient in 40% and factors V, X, and XII were deficient in 20% of cases. In conclusion, Egyptian patients with type 1 Gaucher disease, whether newly diagnosed or receiving enzyme replacement therapy, experience coagulation factor abnormalities regardless the clinical expression of bleeding diathesis. This should be taken into consideration before these patients are subjected to surgery for, e.g., splenectomy, which is common in these patients.

Evaluation of automatic and semiautomatic coagulation assay instruments

The precision of five instruments (Coag-A-Mate, Auto-Fi, Coagulyzer, Electra 600 and Fibrometer) in performing activated partial thrmboplastin time (PTT) assays were compared using three different coagulation reagent systems (Ortho, Dade, and General Diagnostics) utilizing normal and abnormal control reagents. There were wide variations in mean PTT values and co-efficient of variation (CV) among all instruments and for each instrument utilizing different reagents. The smallest CV was noted for The Coagulyzer using Dade reagents, the Coag-A-Mate using Dade and General Diagnostic reagents and the Auto-Fi using General Diagnostic reagents. Auto-Fi values were always longer than those determined with the Fibrometer whereas the optical detection instruments usually gave shorter values. The range of normal values for the prothrombin time (PT) and PTT assay was recorded simultaneously on blood samples of 52 healthy donors utilizing the Coagulyzer with Ortho reagents, the Coag-A-Mate with General Diagnostic reagents nd the Auto-Fi with Dade reagents. No differences were noted between male and female donors. There was a poor correlation among PT results recorded by all instruments. For the PTT assay, results obtained with the Coag-A-Mate and the Auto-Fi had a correlation of 0.84. The normal mean plus 2 or 3 standard deviations determined by the Auto-Fi and the Coag-A-Mate were used to classify blood samples from 263 patients as normal or abnormal when assayed by each instrument. For the PTT assay, coincidence was attained in 91.2% of the samples and discrepancies (a blood classified abnormal by one instrument and normal by the other) were evenly distributed for both instruments. For the PT assay, coincidence occurred in 85.1% of the cases and there was a statistically significant trend (P < 0.05) for the Auto-Fi in classifying abnormal samples categorized normal by the Coag-A-Mate.

Experience with the management of deep vein thrombosis in patients with spinal cord injury. Part II: a critical evaluation of the anticoagulant therapy

Eight acute spinal injury patients with deep vein thrombosis and/or pulmonary emboli are presented witn an in-depth analysis and management of anticoagulation therapy. Special considerations for acute spinal cord injury patients with regards to prophylactic and therapeutic anticoagulation by heparin and coumadin are discussed. There was a wide variation in the requirement of heparin and/or coumadin to maintain effective coagulability which could only be elicited by frequent laboratory monitoring. Inadequate dose and shorter duration of administration of anticoagulant resulted in recurrence of thromboembolism in three out of eight patients in the present series. Haemorrhagic complications were minor and easily manageable. Co-trimoxazole potentiation of coumadin action occurred in two of our patients and it requires special mention as the drug is used increasingly in the treatment of urinary tract infections.