Two Cases of Factor XI Deficiency in Sisters

ABSTRACT

We experienced two cases of factor XI deficiency in a 5 yearr 7 month-old girl, whose chief complaint was coke-colored gross hematuria, and her 9-year-old elder sister. The laboratory findings were prolonged aPTT and prominent deficiency of factor XI. The gross hematuria of the index case was identified due to acute poststreptococcal glomerulonephritis. So we report two cases of factor XI deficiency with a brief review of the related literature.