A useful method for the detection of ethylenediaminetetraacetic acid- and cold agglutinin-dependent pseudothrombocytopenia.
BACKGROUND
Pseudothrombocytopenia (PTCP), caused by platelet (PLT) aggregation, is usually associated with ethylenediaminetetraacetic acid (EDTA)-dependent antibodies and cold aggluti-nins against PLT antigens. The aim of this study was to identify the PTCP and discover the most practical method to distinguish it from real thrombocytopenia.


METHODS
This study included 85 patients without hemorrhagic abnormalities and suspected PTCP. Blood samples containing EDTA, citrate and EDTA-kanamycin (KN) were analyzed at room temperature and 37°C.


RESULTS
PTCP was detected in 24 of 85 patients. In 23 of 24 patients, EDTA-dependent pseudothrombocytopenia (EDTA-PTCP) was detected; 5 of whom had also the cold agglutinin-dependent PTCP. In only 1 of 24 patients, the cold agglu-tinin-dependent PTCP was found. In this study, no significant difference was observed in leukocyte counts comparing EDTA and citrate blood samples in cases with EDTA-PTCP.


CONCLUSIONS
In clinical laboratories, a significant portion of the cases with low PLT counts was attributable to EDTA-PTCP and, therefore, did not require treatment. Even if these cases can be detected by bringing the blood samples containing EDTA to 37°C or by adding KN to blood samples containing EDTA, the use of blood samples containing citrate taken for erythrocyte sedimentation rate analysis is a more practical priority method.
Laboratory of Clinical Biochemistry, Gumussuyu Military Hospital, Taksim, Istanbul, Turkey. 68ozcelik@mynet.com
Fatih
F
Ozcelik
Erol
E
Arslan
Muhittin A
MA
Serdar
Omer
O
Yiginer
Muzaffer
M
Oztosun
Huseyin
H
Kayadibi
Ismail
I
Kurt
D000293:Adolescent; D000328:Adult; D000368:Aged; D003450:Cryoglobulins / Q000009:adverse effects / Q000276:immunology; D004492:Edetic Acid / Q000009:adverse effects* / Q000276:immunology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013921:Thrombocytopenia / Q000139:chemically induced / Q000175:diagnosis* / Q000276:immunology; D055815:Young Adult
D003450:Cryoglobulins; C029443:cold agglutinins; D004492:Edetic Acid