Erythrocyte CD55 expression and its relation to hypercoagulability in Egyptian beta thalassemia patients

Background
Beta thalassemia (BT) is a common type of hereditary hemolytic anemia found in the Mediterranean region. The incidence of thromboembolism in BT patients varies between 1.7 and 9.2%.
Our objective was to assess the expression of CD55 in Egyptian BT patients and evaluate its relationship with the patients’ clinical features, D-dimer levels as a marker of currently activated coagulation, and intraabdominal arterial and venous thrombotic events detected by Doppler.


Patients and methods
We performed a prospective cross-sectional analytical study involving 53 BT patients who regularly attended the Internal Medicine Inpatient Wards and the Hematology Outpatient Clinic.
Laboratory and clinical data were collected, and CD55 and D-dimer levels were assessed for all patients. Color Doppler of the venous and arterial system of the abdomen was performed for all patients. The association between CD55 and various laboratory findings was determined using the Spearman correlation test. In addition, we performed a sensitivity analysis to identify the cutoff point of the CD55 level for diagnosing activated coagulation.


Results
Activated coagulopathy (increased D-dimer) was significantly associated with splenectomy, with a P value of 0.028. Only one patient was diagnosed with chronic portal vein thrombosis. Our results showed that CD55 could not predict activated coagulopathy among the included patients. However, CD55 levels were negatively associated with mean corpuscular hemoglobin and lactate dehydrogenase, with r=−0.33, r−0.28, and P values of 0.016 and 0.045, respectively.


Conclusion
Normal expression of CD55 among thalassemic patients was not correlated with the D-dimer level as a marker of activated coagulopathy.