Complement regulatory proteins in hepatitis-induced thrombocytopenia

Background Thrombocytopenia is a significant concern in individuals with chronic hepatitis infections, especially those who have advanced liver injury. Complement regulatory proteins, namely, CD55 and CD59, may directly disrupt the proper functioning of the complement system. Both proteins are found on platelets and, as a result, might be subjected to autoantibody targeting. This work aimed to assess the expression of complement regulatory proteins (CD59 and CD55) on the platelet surface in patients with hepatitis-associated thrombocytopenia. Methods This case-control study was performed on 90 patients aged 4 to 80. The patients were divided into three equal groups. Group I: included 30 chronic hepatitis patients with hepatitis B virus and thrombocytopenia. Group II: included 30 chronic hepatitis C virus patients with thrombocytopenia. Group III: 30 immune thrombocytopenia patients were used as controls. Results Compared with those in group III CD55, CD59, CD61, and CD42 did not substantially differ among group I and group II patients, however, they significantly decreased when group I was compared with group III control subjects, and they significantly differed when group II was compared group III control subjects. A statistically significant positive correlation existed between absolute counts of CD55 platelets and CD59 platelets as well as between the absolute counts of CD61 platelets and CD42 platelets. Conclusion CD55 and CD59 could be predictors of late-stage hepatitis accompanied by thrombocytopenia, and this information is important for determining the diagnosis and treatment choice. Keywords: CD55, CD59, complement regulatory proteins, hepatitis, thrombocytopenia