Evaluation and Management of Abnormal Bruising in a Teenager
Begin with a comprehensive history focusing on bleeding symptoms, trauma history, medication use, and family bleeding history, followed by targeted laboratory testing only if specific clinical features suggest an underlying bleeding disorder. 1
Initial Clinical Assessment
Critical History Elements
Personal bleeding history: Ask specifically about prolonged bleeding after dental procedures, surgeries (including circumcision), heavy menstrual bleeding in females, frequent nosebleeds requiring medical attention, or bleeding into joints 1, 2, 3
Trauma history: Document the mechanism, timing, and whether the bruising pattern is consistent with the reported injury. Inconsistencies between history and physical findings raise concern for non-accidental trauma 1
Family history: A positive family history of bleeding disorders, particularly maternal inheritance patterns, significantly increases suspicion for conditions like von Willebrand disease 4, 2
Medication review: Identify use of anticoagulants, antiplatelet agents (aspirin, NSAIDs), or supplements that affect coagulation 2, 3
Physical Examination Focus
Bruise characteristics: Note the location, size, pattern, and age of bruises. Bruising over bony prominences (knees, shins) in mobile teens is typically accidental, while bruising on soft tissue areas (abdomen, back, ears, neck) or patterned bruising raises concern for abuse 1, 5
Mucocutaneous bleeding: Petechiae, gingival bleeding, or epistaxis suggest platelet dysfunction or von Willebrand disease 2, 3
Joint swelling or deep hematomas: These findings suggest coagulopathy (factor deficiencies) rather than platelet disorders 2, 3
Laboratory Testing Strategy
Most teenagers with bruising do NOT require laboratory testing if the history and physical examination suggest normal accidental bruising in an active adolescent. 1
Indications for Laboratory Testing
Order initial screening tests if ANY of the following are present: 1, 2, 3
- Bruising disproportionate to reported trauma
- Personal history of excessive bleeding with procedures
- Family history of bleeding disorders
- Bruising in unusual locations (non-bony prominences)
- Associated mucocutaneous bleeding symptoms
Initial Laboratory Panel
If testing is indicated, order: 1, 2, 3
- Complete blood count (CBC) with peripheral blood smear
- Prothrombin time (PT)
- Activated partial thromboplastin time (aPTT)
- Fibrinogen level
Interpretation and Next Steps
Normal PT and aPTT: Consider platelet function disorder, most commonly von Willebrand disease (prevalence 1 in 1,000). Requires specific von Willebrand factor testing (vWF antigen, vWF activity, Factor VIII levels) 4, 2, 3
Normal PT, prolonged aPTT: Suggests intrinsic pathway defect (hemophilia A or B, Factor XI deficiency). Perform mixing study 2, 3
Prolonged PT, normal aPTT: Consider extrinsic pathway defect or vitamin K deficiency 2, 3
Both prolonged: Evaluate for liver disease, disseminated intravascular coagulation, or combined factor deficiencies 2, 3
Critical Pitfalls to Avoid
Normal coagulation studies do NOT rule out von Willebrand disease, which is the most common inherited bleeding disorder and requires specific testing 4, 2
Von Willebrand factor is an acute phase reactant and can be falsely elevated during stress, illness, or inflammation. Repeat testing may be necessary 4
The presence of a bleeding disorder does NOT exclude abuse as the etiology. Both conditions can coexist, or the bleeding disorder may be a consequence of maltreatment 1, 6
Specimen handling is critical: Coagulation tests are very sensitive to improper collection and handling, leading to false-positive results. Use experienced laboratories 1
When to Consult Hematology
Refer to pediatric hematology if: 1, 4
- Initial screening tests suggest a bleeding disorder
- High clinical suspicion persists despite normal initial testing
- Specific expanded testing is needed (platelet function studies, specific factor assays)
- Complex interpretation of results is required
- Testing for rare conditions is preferred
Non-Accidental Trauma Considerations
While teenagers are at lower risk for physical abuse compared to younger children, remain vigilant for: 1, 5
- Bruising patterns inconsistent with developmental stage or reported mechanism
- Bruising in protected areas (torso, ears, neck, genitals)
- Multiple bruises of different ages
- Delay in seeking care
- Changing or inconsistent explanations
Document all findings with photographs and detailed descriptions, as this may be critical for child protection investigations. 7