We report a patient with dysfibrinogenemia treated with purified fibrinogen concentrate who had discrepant post-treatment laboratory values. The patient had mild bleeding symptoms and was diagnosed with dysfibrinogenemia based on fibrinogen activity of 51 mg/dl and antigen of 240 mg/dl. He was treated for an adenoidectomy with purified fibrinogen concentrate (RiaSTAP®) at a dose of 70 mg/kg. A discrepancy in post-treatment fibrinogen activity was observed between the hospital and reference laboratories. Investigation revealed differences in laboratory assay and calibration methods. Fibrinogen concentrate may be a treatment option for patients with dysfibrinogenemia, but accurate laboratory technique is critical for fibrinogen measurement. Pediatr Blood Cancer 2013; 60: 500–502. © 2012 Wiley Periodicals, Inc.