The Importance of Pseudo Thrombocytopenia Due to Platelet Cold Agglutination before Surgery, What Should We Do? A Case Report

Mohammad Ghorbani; Amin Solouki; Farhang Soltani; Amir  Moayedpour; Zahra Khoshnegah

doi:10.18502/ijhoscr.v18i1.14749

Mohammad Ghorbani Laboratory Hematology and Transfusion Medicine, Department of Medical Laboratory Sciences, Faculty of Allied Medicine, Gonabad University of Medical Sciences, Gonabad, Iran
Amin Solouki Department of Hematology and Blood Banking, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Farhang Soltani Department of Internal Medicine, Gonabad University of Medical Sciences, Gonabad, Iran
Amir Moayedpour Islamic Azad University of Medical Sciences, Mashhad, Iran
Zahra Khoshnegah Department of Hematology and Blood Banking, Faculty of Medicine, Gonabad University of Medical Sciences, Gonabad, Iran

DOI: https://doi.org/10.18502/ijhoscr.v18i1.14749

Keywords: Platelet; Thrombocytopenia; Pseudo thrombocytopenia; Cold agglutination; Platelet cold agglutination

Abstract

Platelet cold agglutination (PCA) is a rare in-vitro phenomenon caused by Immunoglobulin M (IgM) autoantibodies, which results in Ethylenediaminetetraacetic Acid (EDTA) independent pseudo thrombocytopenia (PTCP). Its diagnosis is made based on the peripheral blood smear (PBS) examination and pre-test warming blood sample.

Here, a case of PTCP secondary to PCA is presented. He was first admitted for pre-surgical tests but his platelet count was low. His blood was taken with EDTA and sodium citrate anticoagulant to rule pre-analytical error out. Then his sample warmed up and the test was run again with Mindray BC-6000 automated cell counter. Moreover, the rheumatologic tests were done for him.

His platelet count was 23×10⁹/L at first, and PBS showed many platelet aggregates. The low platelet count was not correct with Sodium Citrate or re-sampling with EDTA so platelet satellitism and improper sampling were ruled out. By warming the sample up to 37⸰C, the Platelet count rose to 216×10⁹ / L. The rheumatologic tests were negative except for HLA-B27 which was positive.

Finally, he was diagnosed with PCA which is due to a cold antibody (clinically insignificant). This diagnosis is important for the prevention of recurrent tests, unnecessary platelet transfusion, and other problems. Here these conditions will be discussed.