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

Abstract

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 × 109 to 100 × 109 per L. In preterm infants, 60 percent of Canadian neonatologists commence treatment at a PLT count of between 30 × 109 and 50 × 109 per L. In Germany 32 percent of the physicians start treatment at this level and 25 percent use a threshold of between 10 × 109 and 20 × 109 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 × 109 and 10 × 109 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.

Current perspectives on fetal and neonatal alloimmune thrombocytopenia – increasing clinical concerns and new treatment opportunities

“…Preventing ICH by increasing platelet count above a certain threshold is therefore considered a neonatal emergency, and prompt correction by platelet transfusion should be done based on clinical suspicion without awaiting laboratory confirmation of the diagnosis 4. However, it is not clear what threshold should be used to trigger platelet transfusion 121,122. Previous reports also suggest that neonates with HPA-5b incompatibility may be at risk of bleeding at higher platelet counts compared with HPA-1 incompatibility 39.…”

A review of pathophysiology and current treatment for neonatal alloimmune thrombocytopenia (NAIT) and introducing the Australian NAIT registry

“…As with antenatal management, many important questions remain about the post‐natal management of NAIT. A recent systematic literature search failed to identify any randomised controlled trials or systematic reviews that compared different platelet thresholds for the transfusion of platelets for affected neonates and found that recommendations in the literature vary from a threshold of 30–100 × 10 9 /L 40 . This paper also surveyed clinicians and identified significant variation in transfusion practice.…”

Allo-immune Thrombocytopaenia

“…3 Unlike haemolytic disease in the newborn, AITP can also occur in the first pregnancy if there is parental incompatibility.…”