A systematic review and survey of the management of unexpected neonatal alloimmune thrombocytopenia

BACKGROUND: Unexpected neonatal alloimmune thrombocytopenia (NAIT) may have devastating consequences and its management is challenging. To design future trials, evidence from the literature and existing best practice need review. STUDY DESIGN AND METHODS: This study was a cross-sectional survey of neonatal units in Germany and Canada to determine management strategies of NAIT and a systematic search for randomized controlled trials (RCTs). RESULTS: Management of NAIT differs substantially between countries with regard to platelet (PLT) thresholds for screening, initiation of therapy, and treatment. Seventy-seven percent of Canadian physicians versus 68 percent of German physicians screen preterm and term infants, at a PLT threshold of 30 x 10(9) to 100 x 10(9) per L. In preterm infants, 60 percent of Canadian neonatologists commence treatment at a PLT count of between 30 x 10(9) and 50 x 10(9) per L. In Germany 32 percent of the physicians start treatment at this level and 25 percent use a threshold of between 10 x 10(9) and 20 x 10(9) per L. In term infants, 6 percent of the Canadian physicians and 16 percent of the German physicians use even lower treatment triggers of between 5 x 10(9) and 10 x 10(9) per L. In the presence of bleeding, 61 percent of German physicians await the arrival of antigen-negative PLTs, while 64 percent of Canadian neonatologists prefer intravenous immunoglobulin or random-donor PLTs (81%). Maternal PLTs are utilized by 31 percent of physicians in both countries. No RCTs were identified. CONCLUSION: In the absence of RCTs, management of unexpected NAIT differs between countries. Clinicians and transfusion services may use the results of our study to develop collaborative protocols, redefine preferred hospitalwide strategies, and design future controlled trials.