What is the most appropriate next step for a 14-year-old female with heavy menstrual bleeding, easy bruising, and bleeding from cuts, with normal Complete Blood Count (CBC), platelet count, Partial Thromboplastin Time (PTT), Prothrombin Time (PT), and fibrinogen levels?

Evaluation for von Willebrand Disease or Platelet Function Disorder

The most appropriate next step is to test for von Willebrand disease (VWD) with von Willebrand factor antigen (VWF:Ag), von Willebrand factor activity (VWF:RCo or VWF:GPIbM), and factor VIII levels, ideally drawn during menstruation to capture the lowest values. 1, 2

Clinical Context

This 14-year-old presents with a classic bleeding phenotype—heavy menstrual bleeding (HMB) combined with easy bruising and prolonged bleeding from cuts—yet has normal routine coagulation studies. This pattern strongly suggests an underlying bleeding disorder that requires specific testing beyond standard screening tests. 1, 3

• VWD is the most common inherited bleeding disorder in women, affecting 1-2% of the population, and menorrhagia occurs in 32-100% of women with VWD 2
• The combination of mucocutaneous bleeding (bruising, cuts) with HMB significantly increases the likelihood of an underlying bleeding disorder 1, 3
• Normal PT, PTT, platelets, and fibrinogen do not rule out VWD or platelet function disorders 1, 2

Specific Testing Algorithm

Primary Testing (During Menses if Possible)

• VWF antigen (VWF:Ag) 1, 2
• VWF activity (VWF:RCo or VWF:GPIbM) 1, 2
• Factor VIII coagulant activity (FVIII:C) 1, 2
• Complete blood count with ferritin to assess for iron deficiency anemia from chronic blood loss 1

Critical timing consideration: Laboratory testing should ideally be performed during menstrual bleeding to capture the lowest levels of VWF:Ag and FVIII:C, as these values can fluctuate 2

Secondary Testing if Initial Results Are Borderline or Normal

• Platelet function testing (PFA-100 or platelet aggregation studies) if VWD testing is normal but clinical suspicion remains high 1, 3
• Repeat VWD testing if initial values are borderline (VWF levels 30-50 IU/dL), as stress, inflammation, and hormonal factors can temporarily elevate VWF levels 2

Coordination of Care

Work in coordination with a hematologist for laboratory evaluation and medical management if you suspect a bleeding disorder 1. This is particularly important because:

• Interpretation of VWD testing can be complex, especially in adolescents 1
• Type 1 VWD (the most common form) may have borderline normal values that require expert interpretation 2
• Platelet function disorders require specialized testing not available in all laboratories 3

Common Pitfalls to Avoid

Do Not Assume Normal Screening Tests Rule Out Bleeding Disorders

• PT and PTT are insensitive for detecting VWD and platelet function disorders 1, 2
• Up to 20% of women with HMB have an underlying inherited bleeding disorder despite normal routine coagulation studies 3

Do Not Delay Testing While Initiating Symptomatic Treatment

• You can simultaneously initiate treatment for HMB (tranexamic acid, hormonal therapy) while pursuing diagnostic workup 1, 4
• However, hormonal contraceptives may artificially raise VWF levels, so ideally obtain testing before starting hormonal therapy or during the hormone-free interval 2

Do Not Overlook the Bleeding History

• A detailed bleeding history using a standardized bleeding assessment tool increases diagnostic sensitivity to 95% when combined with objective menstrual assessment (PBAC score >100) 2
• The presence of bleeding symptoms beyond menstruation (easy bruising, prolonged bleeding from cuts) significantly increases pre-test probability of a bleeding disorder 1, 3

Immediate Management Considerations While Awaiting Results

Assess Severity

• Check orthostatic vital signs and hemoglobin/hematocrit to assess hemodynamic stability 1
• Measure serum ferritin to evaluate iron stores 1

Consider Empiric Treatment

• Tranexamic acid (antifibrinolytic) can be used empirically for acute HMB while awaiting test results 1, 4, 2
• Combined hormonal contraceptives are effective for HMB but should ideally be started after VWD testing is completed 1, 4
• NSAIDs (if not contraindicated) can reduce menstrual blood loss by 20-50% 4

Why Other Approaches Are Insufficient

• Empiric hormonal treatment alone without diagnostic workup misses the opportunity to identify a bleeding disorder that will affect surgical planning, dental procedures, and future pregnancy management 1
• Observation without testing is inappropriate given the clear bleeding phenotype beyond menstruation 1, 3
• Gynecologic imaging (ultrasound) would be appropriate if structural causes were suspected, but the history of easy bruising and bleeding from cuts points to a systemic bleeding disorder rather than a structural uterine problem 5