The purpose of this study was to investigate the incidence of clinically common EDTA-dependent pseudo-thrombocytopenia (EDTA-PTCP) and methols for treating this diseese. A total of 1326 cases of thrombocytopenia found at blood routine examination were amalyzed anong 71 535 patients hospitalized in our hospital from January 2010 to May 2013, and 87 cases of PTCP caused EDTA-K anticoagulant were analyzed again by using sodium citrate auticoagulant, at the same time the platelet formation distribution was observed by microscopy of smear with Wright-Giemsa staining. The results showed that the platelet count detected by using EDTA-K anticoagulant in 87 cases was (56 ± 27)×10(9)/L, while the platelet count detected by using sodium citrate was (185 ± 39)×10(9)/L (t = 1.83,P < 0.01). The pseudo-thrombocytopenia incidence cansed by EDTA-K was 0.12%, it was 6.56% for the total number of thrombocytopenia. It is concluded that the incidence of PTCP cansed by EDTA-K is 0.12%, the PTCP is easily misdiagnosed. Therefore, the specimens of platelet count <100 10(9)/L should be tested again. When the platelet aggregation is found, the specimens should be examined again by using sodium citrate in order to avoid misdiagnosis.
Aged ; Anticoagulants ; adverse effects ; Citrates ; Edetic Acid ; adverse effects ; Humans ; Incidence ; Platelet Aggregation ; Platelet Count ; Thrombocytopenia ; chemically induced

BACKGROUNDPlatelet (PLT) clumping occurring in pseudothrombocytopenia (PTCP) can result in inaccurate PLT. Automated platelet clump count (APCC) is a quantitative parameter of platelet aggregation. In this study, we evaluated the clinical utility of APCC in the screening for platelet aggregation related ethylene diamine tetraacetic acid (EDTA)-dependent PTCP (EDTA-PTCP).

METHODSA total of 105 patients and 200 healthy individuals were enrolled in this study. Blood samples were collected with dipotassium EDTA and sodium citrate respectively. ADVIA 2120 hematology analyzer was used to perform complete blood count (CBC) and APCC. Blood smears of both EDTA- and citrate-anticoagulated samples were made for microscope observation and manual PLT counting.

RESULTSIn 25 patients with EDTA-PTCP patients, for EDTA-2K anticoagulated-blood, PLT was (55 ± 6) × 10(9)/L, significantly lower than citrate anticoagulated blood ((186 ± 13) × 10(9)/L)). APCC was (905 ± 694) × 10(9)/L, significantly higher than citrate anticoagulated blood (98 ± 37) × 10(9)/L. In true thrombocytopenia and healthy control groups, APCC was (63 ± 60) × 10(9)/L and (69 ± 59) × 10(9)/L respectively and there was no significant difference between EDTA and citrate anticoagulants. Receiver operator characteristic (ROC) curve showed both sensitivity and specificity of APCC were 96% when the cutoff value of APCC was set as 182 × 10(9)/L. Other platelet parameters had poor performance.

CONCLUSIONThe APCC has a good sensitivity and specificity in differentiating EDTA-PTCP from true thrombocytopenia compared with other platelet parameters.

Adult ; Edetic Acid ; adverse effects ; Female ; Humans ; Male ; Middle Aged ; Platelet Aggregation ; drug effects ; Platelet Count ; methods ; Thrombocytopenia ; diagnosis ; Young Adult

EDTA-dependent pseudothrombocytopenia (PTCP) is the phenomenon of a spurious low platelet count due to EDTA-induced aggregation of platelets. Since the failure to recognize EDTA-dependent PTCP may result in incorrect diagnosis and inappropriate treatment, the recognition of this phenomenon is very important. We report an insidious case of EDTA-dependent PTCP confirmed by supplementation of kanamycin to anticoagulant in a 53-year-old women. Although sodium citrate and heparin usually prevented the aggregation of platelets in EDTA-dependent PTCP patients, these anticoagulants failed in preventing PTCP in our case. EDTA-dependent PTCP was confirmed by the findings that the clumping of platelets on microscopic evaluation was found in EDTA-anticoagulated blood samples, whereas thrombocytopenia and platelet aggregation were not revealed in the sample supplemented with kanamycin.
Antibiotics, Aminoglycoside/*pharmacology ; Anticoagulants/*adverse effects/pharmacology ; Case Report ; Edetic Acid/*adverse effects ; Female ; Human ; Kanamycin/*pharmacology ; Middle Age ; Platelet Aggregation/*drug effects ; Platelet Aggregation Inhibitors/*therapeutic use ; Platelet Count ; Thrombocytopenia/*blood/chemically induced