Since Oct 2006, we experienced 10 cirrhosis patients showing the unexpected elevation of cholinesterase (ChE) activity after endoscopic injection sclerotherapy (EIS) for esophageal varix. Comparing these patients with the six patients who did not show the elevation of the enzyme, we found that in former patients haptoglobin was infused after EIS to avoid hemolysis. Haptoglobin is a blood-born product and contaminated with ChE whose chemical properties is similar to those of haptoglobin. Moreover, manufacturer altered their processing system since Oct 2004, which deteriorated the contamination. We conclude that the contaminated ChE activity in haptoglobin raised serum ChE activities in cirrhosis patients who had EIS for esophageal varix.
