Cherry-red plasma: Beyond the assumption of hemolysis

Hemolysis is the most prevalent pre-analytical interfering factor and a major source of error in laboratory analysis. The examination of samples post-centrifugation can provide valuable information regarding pre-analytical interferences. In this unusual case, a patient’s plasma specimen was cherry-red after centrifugation, which is most usually indicative of hemolysis. However, subsequent investigations ruled out common hemolysis causes. We eventually determined that the patient’s cherry-red plasma was most likely caused by other factors in the patient’s medical history, including cancer treatment with PV-10 (rose bengal disodium 10%). We then conducted an interference study to comprehensively assess the effects of PV-10 on various biochemical tests, especially liver function tests and bilirubin levels. The findings indicate that PV-10 has varying effects on different biochemical assays and test results should be examined individually. This report underlines the need for awareness of potential drug interference on laboratory tests for better result interpretation and making clinical decisions.