Reference interval of platelet counts and other platelet indices in apparently healthy blood donors in North India according to Clinical and Laboratory Standards Institute guidelines: Need to redefine the platelet count cutoffs for repeat plateletpheresis donation?

Background: In clinical practice, laboratory results are of great importance for the diagnosis and treatment. Reference intervals of different parameters aid health-care professionals in the interpretation of results. There are very few studies on reference intervals from India. This prospective study was conducted to determine the reference intervals for platelet count (PLT) and PLT indices; mean PLT volume (MPV), PLT distribution width (PDW), and PLT large cell ratio (P-LCR). These values can be obtained as a part of a routine complete blood count (CBC) and have diagnostic and prognostic significance in certain diseases. PLT count is an important criterion for the selection of donors for repeat plateletpheresis donation.

Materials and methods: Sixteen hundred and thirty-four first-time healthy volunteer plateletpheresis donors were enrolled for the study. CBC was done, values of PLT, MPV, PDW, and P-LCR were noted, and the results were analyzed. The 95% of the reference distribution was estimated using the 2.5th and 97.5th percentiles following Clinical and Laboratory Standards Institute guidelines. Adverse donor reactions, if any and quality parameters of single donor PLTs (SDP) were also studied.

Results: Reference range values of PLT, MPV, PDW, and P-LCR were 137,825-355,175/μl, 8.1-13.9/fl, 9.1-22.5/fl, and 11.7%-52.9%, respectively, and compared well with other published studies from India. It was observed that reference values of PLT count obtained in the study were lower than reference values that are currently used in most laboratories (150,000-450,000/μl) in India.

Conclusion: Based on our results, we are of the opinion that the PLT count cutoffs for repeat plateletpheresis donation may need to be revised downwards for our country which would also mitigate the scarcity of apheresis donors.