Female gender, older age at presentation and the presence of antinuclear antibodies were among the characteristics that predicted chronic immune thrombocytopenia in children, according to results of a meta-analysis.
Researchers also observed a considerable protective effect of IV immunoglobulin alone against chronic immune thrombocytopenia.
Katja M.J. Heitink-Pollé, MD, of University Medical Center Utrecht and Wilhelmina Children’s Hospital in the Netherlands, and colleagues reviewed data from 54 studies conducted between 1975 and 2013. All studies included children aged 3 months to 18 years who were newly diagnosed with immune thrombocytopenia. The number of children in each study ranged from 43 to 1,984.
Chronic immune thrombocytopenia — or thrombocytopenia ˂100 x 109/L for more than 12 months — occurs in about 20% to 25% of cases.
When researchers reviewed the studies, they determined clinical predictors of chronic immune thrombocytopenia included female gender (OR=1.17; 95% CI, 1.04-1.31), absence of previous infections or vaccinations (OR=3.08; 95% CI, 2.19-4.32), and insidious onset of immune thrombocytopenia (OR=11.27; 95% CI, 6.27-20.27).
Age older than 11 years also was associated with chronic immune thrombocytopenia (OR=2.47; 95% CI, 1.94-3.15), and patients who developed chronic disease were a mean 2.68 years older (95% CI, 1.89-3.47) than those with disease resolution.
Researchers identified two laboratory measures — platelet counts ≥20 x 109/L at presentation (OR=2.15; 95% CI, 1.63-2.83) and the presence of antinuclear antibodies (OR=2.87; 95% CI, 1.57-5.24) — that increased risk for development of chronic immune thrombocytopenia.
Researchers determined patients treated with a combination of methylprednisolone and IV immunoglobulin were more likely to develop chronic immune thrombocytopenia (OR=2.67; 95% CI, 1.44-4.96), yet patients treated with IV immunoglobulin alone were less likely to develop chronic disease (OR=0.71 95% CI, 0.52-0.97).
“The protective effective of IV immunoglobulin is remarkable and needs confirmation in prospective randomized trials, as well as future laboratory studies to elucidate the mechanism of this effect,” Heitink-Pollé and colleagues wrote.
Patients who had mucosal bleeding at diagnosis also were less likely to develop chronic immune thrombocytopenia (OR=0.39; 95% CI, 0.28-0.54).
“The information provided by our systematic review serves the need for identification of reliable predictors for the outcome of immune thrombocytopenia and will guide researchers in the field of pediatric as well as adult immune thrombocytopenia to reflect on their own research as well as to design future studies,” the researchers concluded. “Based on our review, new prediction scores can be generated and tested in large cohorts of patients. To be able to compare prognostic risk factors, in future studies all predictors should be strictly defined and be recorded at time of diagnosis of immune thrombocytopenia. In this way, we might be able to identify patients at higher risk of developing chronic immune thrombocytopenia who may benefit from treatment to prevent a chronic course of immune thrombocytopenia.”
Disclosure: The researchers report no relevant financial disclosures.