Autologous 111 In-labelled platelet sequestration studies in patients with primary immune thrombocytopenia (ITP) prior to splenectomy: A report from the United Kingdom ITP Registry

Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
British Journal of Haematology (Impact Factor: 4.71). 10/2010; 151(5):477-87. DOI: 10.1111/j.1365-2141.2010.08377.x
Source: PubMed


While splenectomy is an effective therapy for primary immune thrombocytopenia (ITP), possible complications and observed non-complete response (CR) in one-third of patients demonstrate the need for further research into potential pre-surgical predictors of outcomes. Past investigations into platelet sequestration studies, a hypothesized predictive test, have adopted heterogeneous methods and varied widely with regard to power. By studying patients with primary ITP who underwent autologous (111) In-labelled platelet sequestration studies at Barts and The London NHS Trust between 1994 and 2008, we evaluated the effectiveness of sequestration site in predicting short, medium, and long-term CR (platelet count >100 × 10(9) /l) to splenectomy through multivariate (gender, age at splenectomy, and mean platelet lifespan) logistic regression modelling. In total, 256 patients with primary ITP underwent scans; 91 (35·5%) proceeded to splenectomy. Logistic regression revealed significant adjusted odds ratios for CR of 7·47 (95% confidence interval [CI], 1·89-29·43) at 1-3 months post-splenectomy, 4·85 (95% CI, 1·04-22·54) at 6-12 months post-splenectomy, and 5·39 (95% CI, 1·34-21·65) at last follow-up (median: 3·8 years [range: 0·5-13·1 years]) in patients with purely or predominantly splenic versus mixed or hepatic sequestration. These findings demonstrate the utility of autologous (111) In-labelled platelet sequestration studies as an adjunct predictive instrument prior to splenectomy.

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Available from: Adrian Newland, Sep 15, 2014
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    • "A simple exponential (random) consumption model is also sometimes used when the platelet consumption curve appears (by eye) to be purely exponential [24], [25], [26], an approach recommended in the 1970’s by an international panel [27]. There are however no agreed upon criteria for deciding when platelet consumption is sufficiently non-exponential to invalidate this method. "
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