Acquired bisalbuminemia: A case report

Background: Bisalbuminemia is a rare condition characterized by the presence of two distinct albumin peaks with different mobilities on serum protein electrophoresis (SPE). It may be inherited or acquired. In several cases it can result from interactions with different metabolites. Methods: A 36-year-old woman, with a history of intrahepatic cholestasis of pregnancy and a subsequent episode of severe cholestatic jaundice, underwent biochemical and haematological tests. SPE profile at capillary electrophoresis (CE) revealed an abnormal peak in the alpha1 region, suggestive of acquired bisalbuminemia. To investigate the nature of the ‘atypical’ SPE profile, we performed PEG treatment on the patient's serum. Results: The experiments performed after PEG treatment confirmed that the iatrogenic bisalbuminemia was due to the albumin-bile acids complex. Furthermore, neither standard nor high-resolution (HR) agarose gel electrophoresis (AGE) revealed bisalbuminemia, detected by CE. The patient's treatment with odevixibat reduced bile acid and other cholestasis parameters, led to the disappearance of bisalbuminemia. Conclusion: In this case we demonstrated that acquired bisalbuminemia is related to the formation of albumin–bile acids complex. We observed that bisalbuminemia was absent on AGE, both in classical and HR electrophoresis, leading us to conclude that the interference due to albumin–bile acids complex was detected only in CE technique. A critical laboratory approach is essential to distinguish analytical interferences from clinically relevant abnormalities, allowing clinicians to make informed diagnostic and therapeutic decisions.