Korean J Lab Med.  2007 Feb;27(1):1-6. 10.3343/kjlm.2007.27.1.1.

Clinical Usefulness of the Simple Technique to Diagnose Thrombocytopenia Using Immature Platelet Fraction

• Cho YG
• Lee JH
• Kim DS
• Lee HS
• Choi SI

• KMID: 1121651
• DOI: http://doi.org/10.3343/kjlm.2007.27.1.1

Abstract

BACKGROUND: Immature platelet fraction (IPF) is the percentage of reticulated platelet (RP) of total platelet count. We measured an IPF reference range using XE-2100 blood cell counter with upgraded software (Sysmex, Japan) and evaluated the clinical utility of this parameter for the laboratory diagnosis of thrombocytopenia due to an increase in peripheral platelet destruction. METHODS: Peripheral blood samples collected into K2 EDTA (Beckton Dickinson, USA) were analyzed at Chonbuk National University Hospital. One hundred forty-two samples from apparently healthy adults (all routine full blood count parameters including platelets within the healthy reference range) were used to establish a normal reference range for IPF. The patients were classified into 3 groups including hypoplastic (consisted of 22 patients undergoing chemotherapy with falling platelet counts and 14 with aplastic anemia), cirrhotic (40 with cirrhosis of liver), and idiopathic thrombocytopenic purpura (ITP) (14 with ITP) groups. RESULTS: An IPF reference range in healthy individuals was established as 0.4-5.4%, with a mean of 1.7%. A significant increase in IPF values was found in the ITP patient group. The cut-off value of IPF was 6.1% and its sensitivity and specificity were 92.9%, and 82.9% respectively. Reproducibility was good. CONCLUSIONS: A rapid, inexpensive automated method for measuring IPF is feasible and should become a standard parameter in evaluating thrombocytopenic patients.

Keyword

Reticulated platelet; Immature platelet fraction; Idiopathic thrombocytopenic pur-pura; Aplastic anemia

MeSH Terms

Adolescent
Adult
Aged
Aged, 80 and over
Child
Child, Preschool
Female
Humans
Infant
Male
Middle Aged
Platelet Count/*methods
Stem Cells/cytology
Thrombocytopenia/*diagnosis

Figure

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  Fig. 1. Optical platelet scattergram from a patient with high IPF value.

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  Fig. 2. Comparison of mean IPF values between control and patients. Mean IPF from ITP group was significantly higher than those from control, hypoplastic, and cirrhotic groups (P<0.05). However, its difference between control and non-ITP patients group was not significant.

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  Fig. 3. ROC curve shows that the cut-off value (indicated as O) of IPF is 6.1%, its sensitivity and specificity are 92.9% and 82.9%, respectively.

Reference

References

1. Do JH, Park JS, Park TH, Lee EY, Son HC, Kim SH, et al. Clinical usefulness of measurement of reticulated platelets by thiazole orange in idiopathic thrombocytopenic purpura. Korean J Clin Pathol. 1999; 19:156–62.

2. Heo WB, Kim YK, Lee NY, Won DI, Suh JS. Estimate of thrombopoiesis by flow cytometric analysis of reticulated platelets in patients with severe thrombocytopenia. Korean J Lab Med. 2005; 25:7–13.

3. Cho YG, Kim JH, Kim DS, Choi SI, Lee HS. Quantitation of the percentage of reticulated platelets to diagnose the cause of thrombocytopenia. Korean J Lab Med. 2005; 25:365–72.

4. Toba K, Fuse I, Koike T, Tsuchiyama J, Higuchi W, Niikuni K, et al. Clinical application of reticulated platelet analysis using the matic-modified thiazole orange method and flow cytometry. Rinsho Ketsueki. 2000; 41:1151–7.

5. Saxon BR, Blanchette VS, Butchart S, Lim-Yin J, Poon AO. Reticulated platelet counts in the diagnosis of acute immune thrombocytopenic purpura. J Pediatr Hematol Oncol. 1998; 20:44–8.

6. Matic GB, Chapman ES, Zaiss M, Rothe G, Schmitz G. Whole blood analysis of reticulated platelets: improvements of detection and assay stability. Cytometry. 1998; 34:229–34.

7. Briggs C, Kunka S, Hart D, Oguni S, Machin SJ. Assessment of an immature platelet fraction (IPF) in peripheral thrombocytopenia. Br J? Haematol. 2004; 126:93–9.

8. Abe Y, Wada H, Tomatsu H, Sakaguchi A, Nishioka J, Yabu Y, et al. A simple technique to determine thrombopoiesis level using immature platelet fraction (IPF). Thromb Res. 2006; 118:463–9.

9. Ault KA, Rinder HM, Mitchell J, Carmody MB, Vary CP, Hillman RS. The significance of platelets with increased RNA content (reticulated platelets). A measure of the rate of thrombopoiesis. Am J Clin Pathol. 1992; 98:637–46.

10. Rinder HM, Munz UJ, Ault KA, Bonan JL, Smith BR. Reticulated platelets in the evaluation of thrombopoietic disorders. Arch Pathol Lab Med. 1993; 117:606–10.

11. Romp KG, Peters WP, Hoffman M. Reticulated platelet counts in patients undergoing autologous bone marrow transplantation: an aid in assessing marrow recovery. Am J Hematol. 1994; 46:319–24.

12. Richards EM, Baglin TP. Quantitation of reticulated platelets: methodology and clinical application. Br J Haematol. 1995; 91:445–51.

13. Peterec SM, Brennan SA, Rinder HM, Wnek JL, Beardsley DS. Reticulated platelet values in normal and thrombocytopenic neonates. J Pediatr. 1996; 129:269–74.

14. Joseph MA, Adams D, Maragos J, Saving KL. Flow cytometry of neonatal platelet RNA. J Pediatr Hematol Oncol. 1996; 18:277–81.

15. Lee LG, Chen CH, Chiu LA. Thiazole orange: a new dye for reticulocyte analysis. Cytometry. 1986; 7:508–17.

16. Watanabe K, Takeuchi K, Kawai Y, Ikeda Y, Kubota F, Nakamoto H. Automated measurement of reticulated platelets in estimating thrombopoiesis. Eur J Haematol. 1995; 54:163–71.