Hypofibrinogenemia as a clue in the presumptive diagnosis of acute promyelocytic leukemia

- The fibrinogen level was the most useful parameter to predict APL diagnosis;.
- A low fibrinogen level was associated with higher early mortality;.
- The prognostic ability of the fibrinogen level increased for patients with high risk APL.

Acute promyelocytic leukemia (APL) is a medical emergency. In order to evaluate the usefulness of initial coagulation parameters in the predictive value of APL diagnosis, 1304 consecutive newly diagnosed acute leukemia patients, including APL (n = 211), non-APL acute myeloid leukemia (n = 781) and acute lymphoblastic leukemia (n = 312) were retrospectively evaluated between January 2011 and May 2015. The area under curve (AUC) of fibrinogen was the largest among the coagulation markers based on receiver operating characteristic (ROC) analysis. The optimum cutoff value of fibrinogen was 1.87 g/L (AUC = 0.912, sensitivity 80.1% and specificity 88.8%). The optimum cutoff value of D-dimer was 2191 μg/L (AUC = 0.786, sensitivity 81.1% and specificity 67.8%). The AUC difference between the fibrinogen and D-dimer was significant (P < 0.001). Other coagulation markers showed less predictive power. Importantly, in the analysis of high white blood cell count (over 10 × 109/L) subgroup, a low fibrinogen level could efficiently discriminate APL patients from controls (AUC = 0.983, sensitivity 96.4% and specificity 94.4%) with a criterion value ≤1.71 g/L. Thus, our results suggest that a low fibrinogen level could be a key marker in early prediction of APL diagnosis.