Cold agglutinins - a common clinical or laboratory problem. clinical case

Introduction: The examination of the blood picture is an initial stage in the diagnostic process, both in anaemic and inflammatory conditions. Agglutination of erythrocytes and platelets, as well as hemolysis, can lead to “wrong” values when automatically enumerated with haematology analysers. Purpose: We present a case of in vitro erythrocyte agglutination caused by cold agglutinins as a result of viral pneumonia with the etiologic agent influenza B. Material and methods : This is a man entering a pulmonary ward with pneumonia. The examined blood picture shows abnormal values of the red blood row. The analysis was performed on a Sysmex XN1000 haematology analyzer. The flags and cell cytograms of the apparatus were examined. The morphology of the cellular elements (erythrocytes, leukocytes-DCL and platelets) of stained blood smear was examined microscopically. A saline test was applied to differentiate the in vitro agglutination. We determined the biochemical markers for hemolysis (free haemoglobin in plasma, LDH, Haptoglobin of Olympus AU 640 analyser), the titer of cold agglutinins. Virological serological studies have been appointed. Results: CPC values were monitored from admission to patient discharge and at the end of the first month. The biochemical markers for hemolysis are poorly expressed. The saline test and the erythrocyte morphology give direction to in vitro agglutination. A virological examination found antibodies against influenza type B and Coxiella burnetii (Q fever). Conclusion: A good knowledge of artificially occurring in vitro phenomena resulting from erythrocyte agglutination can avoid a number of misunderstandings or misinterpretations .