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David Mikulis

Publications and source records attributed to David Mikulis.

4 recordsLinked to original sources

A prospective cohort study determining the prevalence of thrombotic events in children with acute lymphoblastic leukemia and a central venous line who are treated with L-asparaginase: results of the Prophylactic Antithrombin Replacement in Kids with Acute Lymphoblastic Leukemia Treated with Asparaginase (PARKAA) Study.

BACKGROUND: Thrombotic events (TEs) are serious secondary complications in children with acute lymphoblastic leukemia (ALL) who receive L-asparaginase (ASP) therapy; however, the prevalence of TEs has not been established. The primary objective of the Prophylactic Antithrombin Replacement in Kids with Acute Lymphoblastic Leukemia Treated with Asparaginase (PARKAA) Study was to determine the prevalence of TEs. The secondary objective was to detect any association of TEs with the presence of congenital or acquired prothrombotic disorders. METHODS: Children with ALL were screened for TEs at the end of ASP treatment using bilateral venograms, ultrasound, magnetic resonance imaging, and echocardiography. Symptomatic TEs were confirmed by appropriate radiographic tests. All tests were read by a blinded central adjudication committee. RESULTS: Twenty-two of 60 children had TEs, a prevalence of 36.7% (95% confidence interval, 24.4-48.8%). TEs were located in the sinovenous system of the brain in 1 patient, the right atrium in 3 patients, and the upper central venous system in 19 patients. TEs detected by venography resulted in 1) 25-100% occlusion, with 1 in 3 patients showing occlusion of > 75% of the greatest vessel dimension, and 2) the presence of collaterals in 60% of patients, with 40% categorized as major. No children with TEs were positive for factor V Leiden or prothrombin gene 20201A, and four of eight children with antiphospholipid antibodies had a TE. CONCLUSIONS: The prevalence of TEs is exceedingly high in this population, and it is likely that the extent of occlusion is likely clinically significant. No trend was seen toward an association between TEs and the presence of congenital prothrombotic disorders. A trend was seen toward an association between TEs and antiphospholipid antibodies. Carefully designed clinical trials of primary prophylaxis for the prevention of TEs are required in this patient population.

Adolescent↗

Trend to efficacy and safety using antithrombin concentrate in prevention of thrombosis in children receiving l-asparaginase for acute lymphoblastic leukemia. Results of the PAARKA study.

An association has been reported between thrombotic events and the use of L-asparaginase (ASP) in children with acute lymphoblastic leukaemia (ALL). The mechanism for thrombosis is likely related to an acquired antithrombin deficiency. Since a primary prophylaxis using antithrombin concentrates may prevent thrombosis, the PARKAA (Prophylactic Antithrombin replacement in kids with ALL treated with L-asparaginase) study was performed. The objectives of PARKAA were to determine if there was a trend to efficacy and safety of antithrombin treatment as assessed by 1) incidence of thrombosis 2) incidence of bleeding and 3) plasma markers of endogenous thrombin generation as surrogate outcomes for thrombosis. The study was not powered to answer the question of efficacy and safety, but rather to detect a trend. PARKAA was an open, randomised, controlled study in children with ALL being treated with ASP. Children were randomised to receive antithrombin infusions or no antithrombin treatment. All thrombotic events were confirmed using bilateral venography, ultrasound, echocardiography and MRI. The incidence of thrombosis in patients treated with antithrombin was 28% (95% CI 10-46%), compared to 37% (95% CI 24-49%) in the non treated arm. Two minor bleeds occurred in patients in the treated arm, but were not considered to be related to antithrombin. No significant differences were seen in plasma markers by the treatment group. In conclusion, treatment with antithrombin concentrate shows a trend to efficacy and safety. In contrast, there was no difference in surrogate markers for thrombosis. Carefully designed clinical trials are needed to test the efficacy and safety of antithrombin in this population.

Adolescent↗

The developing stroke: management decisions.

Radiologists have become important members of a multidisciplinary team aimed at treating stroke. New studies such as the NINDS (National Institute of Neurological Disorders and Stroke) intravenous and PROACT II (prolyse in acute cerebral thromboembolism II) intra-arterial thrombolytic trials for acute stroke have focused attention on the need for rapid management. Radiologists play a key role in the diagnosis and selection of patients who may benefit from these therapies. We review current issues in the computed tomographic and magnetic resonance imaging diagnosis of acute stroke and the data supporting the various treatment options.

Acute Disease↗