The discriminatory power of bleeding assessment tools in adult patients with a mild to moderate bleeding tendency

BACKGROUND

Bleeding assessment tools (BATs) have been developed to quantify bleeding severity. Their ability to predict for the diagnosis of a bleeding disorder has not been thoroughly investigated.

OBJECTIVES

To evaluate the ability of the Vicenza BAT and the ISTH BAT to distinguish patients with an established bleeding disorder from those with bleeding of unknown cause (BUC).

PATIENTS/METHODS

Three-hundred fifty-nine patients (228 with BUC, 64%) from the Vienna Bleeding Biobank were assessed in this study.

RESULTS

The bleeding scores were similar in patients with an established diagnosis of a bleeding disorder compared to patients with BUC. Both BATs had a low sensitivity and specificity for the diagnosis of a bleeding disorder with areas under the receiver operating characteristic (ROC) curves of 0.53 (95% confidence interval 0.47-0.60) for the Vicenza BAT and 0.52 (0.46-0.59) for the ISTH BAT. In terms of specific diagnoses, both scores were most accurate in diagnosing von Willebrand disease (VWD, areas under the ROC curve; Vicenza BAT 0.67 (0.45-0.90); ISTH BAT 0.70 (0.50-0.90)). A separate evaluation of different bleeding symptoms in patients who had undergone surgery and tooth extraction revealed that postpartum bleeding and bleeding from small wounds was predictive for diagnosing a MBD in multivariable analysis.

CONCLUSIONS

The Vicenza- and the ISTH BAT have a low ability to distinguish patients with an established bleeding disorder from those with BUC.

[A diagnostic approach to relatively common mild bleeding symptoms: screening of congenital mild bleeding disorders]

Although mild skin and mucosal bleeding symptoms are common in patients with inherited bleeding disorders, both can also be observed in healthy individuals. These bleeding symptoms may be caused by disorders of primary hemostasis (i.e., von Willebrand disease and platelet function disorders), mild deficiencies of clotting factors and some rare hyper fibrinolytic disorders are also included. To date, mild bleeding symptoms pose a frequent and substantial diagnostic challenge, and the definitive diagnosis of inherited bleeding disorders is not feasible in a vast majority of individuals despite an extensive laboratory workup. However, it must be diagnosed precisely to avoid severe complications and decrease bleeding risks before invasive procedures. Thus, a comprehensive diagnostic approach, from structured patient history to highly specialized laboratory diagnosis, is warranted to establish diagnosis of inherited bleeding disorders. Furthermore, the prophylaxis should be offered to prevent excessive bleeding in these patients with bleeding symptoms, even if they remain undiagnose of bleeding disorders.

Fibrinolysis in patients with a mild-to-moderate bleeding tendency of unknown cause

In more than 50% of patients with a mild-to-moderate bleeding tendency, no underlying cause can be identified (bleeding of unknown cause, BUC). Data on parameters of fibrinolysis in BUC are scarce in the literature and reveal discrepant results. It was the aim of this study to investigate increased fibrinolysis as a possible mechanism of BUC. We included 270 patients (227 females, median age 44 years, 25–75^th percentile 32–58) with BUC and 98 healthy controls (65 females, median age 47 years, 25–75^thpercentile 39–55). Tissue plasminogen activator (tPA-) antigen and activity, plasminogen activator inhibitor type-1 (PAI-1), tPA-PAI-1 complexes, thrombin activatable fibrinolysis inhibitor (TAFI), α2-antiplasmin, and D-dimer were determined. While PAI-1 deficiency was equally frequent in patients with BUC and controls (91/270, 34%, and 33/98, 34%, p = 0.996), tPA activity levels were more often above the detection limit in patients than in controls (103/213, 48%, and 23/98, 23%, p < 0.0001). We found lower levels of tPA-PAI-1 complexes (6.86 (3.99–10.00) and 9.11 (7.17–13.12), p < 0.001) and higher activity of TAFI (18.61 (15.80–22.58) and 17.03 (14.02–20.02), p < 0.001) and α2-antiplasmin (102 (94–109) and 98 (90–106], p = 0.003) in patients compared to controls. Detectable tPA activity (OR 3.02, 95%CI 1.75–5.23, p < 0.0001), higher levels of TAFI (OR 2.57, 95%CI 1.48–4.46, p = 0.0008) and α2-antiplasmin (OR 1.03, 95%CI 1.01–1.05, p = 0.011), and lower levels of tPA-PAI-1 complexes (OR 0.90, 95%CI 0.86–0.95, p < 0.0001) were independently associated with BUC in sex-adjusted logistic regression analyses. We conclude that the fibrinolytic system can play an etiological role for bleeding in patients with BUC.