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Symptomatic factor XIII deficiency with normal urea solubility test
Background:
Factor XIII deficiency is a rarely encountered bleeding disorder traditionally identified by clot dissolution in 5 molar urea (urea solubility test).
Methods:
We report a patient with delayed post-surgical bleeding characteristic of factor XIII deficiency with a normal urea solubility test.
Results:
Factor XIII deficiency was identified by an automated assay that measured factor XIII antigen. The patient was successfully treated with cryoprecipitate.
Conclusions:
Patients with excessive bleeding with normal screening tests should be tested for factor XIII using a sensitive assay procedure. The urea solubility assay for factor XIII should be discontinued due to its lack of sensitivity.
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