Pertinent Negatives for Easy Bruising in an 18-Year-Old
When evaluating an 18-year-old with easy bruising, you must systematically inquire about bleeding symptoms, medication exposures, family history, and connective tissue manifestations to distinguish between benign causes, inherited bleeding disorders, and systemic conditions. 1, 2
Personal Bleeding History
Ask specifically about these bleeding manifestations that suggest an underlying disorder:
- Significant bleeding after surgery or dental procedures – particularly wisdom tooth extraction, tonsillectomy, or any prior surgical intervention 1, 2
- Prolonged or recurrent epistaxis requiring medical intervention or cauterization 1, 2
- Heavy menstrual bleeding (menorrhagia) requiring pad/tampon changes more frequently than every 2 hours, lasting >7 days, or causing anemia 1, 3
- Bleeding from umbilical stump in infancy (if historical information available) 1
- Bleeding after circumcision in males, which is a classic presentation of von Willebrand disease 4
- Joint hemorrhages or muscle hematomas without significant trauma 2
- Gastrointestinal bleeding (hematemesis, hematochezia) 1
Medication and Supplement Review
Document all substances that can increase bleeding tendency:
- Anticoagulants (warfarin, direct oral anticoagulants) 3, 2
- Antiplatelet agents (aspirin, clopidogrel) 3, 2
- NSAIDs (ibuprofen, naproxen) – these affect platelet function and test results 1, 3, 2
- Corticosteroids – can cause vascular fragility 3
- Certain antibiotics that interfere with vitamin K metabolism 3
- Alternative therapies and herbal supplements (ginkgo biloba, fish oil, garlic supplements) 1, 2
Family History
Inquire about bleeding disorders in blood relatives:
- Specific diagnosed bleeding disorders in family members, particularly von Willebrand disease (the most common inherited bleeding disorder affecting 1 in 1,000 people) 1, 3, 4
- Maternal inheritance pattern – von Willebrand disease affects both males and females equally and can show maternal transmission 4
- Ethnicity associated with higher rates of certain bleeding disorders (e.g., Amish populations) 1
- Undiagnosed bleeding symptoms in relatives – many mild cases go unrecognized 4
Connective Tissue and Systemic Symptoms
Screen for conditions that can mimic or coexist with bleeding disorders:
- Joint hypermobility – assess with Beighton score, as benign hypermobility syndromes are associated with abnormal bleeding even when coagulation studies are normal 5
- Skin hyperextensibility or fragility suggesting Ehlers-Danlos syndrome 1, 6
- Dietary deficiencies – particularly vitamin C (scurvy) or vitamin K deficiency 1
- Constitutional symptoms such as fever, weight loss, night sweats suggesting malignancy or infiltrative disorders 1, 3
- Liver disease symptoms – jaundice, abdominal distension, known cirrhosis 3
Bruising Pattern and Location
Determine if bruising location suggests underlying pathology versus normal activity:
- Bruises on soft-tissue areas (thighs, upper arms, trunk) are more indicative of bleeding disorders than bruises over bony prominences from normal activity 3
- Absence of trauma history that adequately explains the bruising pattern 1, 2
- Spontaneous bruising without any recalled trauma 3
- Patterned bruising (which would suggest trauma rather than bleeding disorder) 1
Critical Pitfalls to Avoid
Do not assume normal screening tests rule out bleeding disorders – PT and aPTT do not reliably detect von Willebrand disease, Factor XIII deficiency, or platelet function disorders 1, 3, 2, 4
Do not overlook mild hemophilia – mild Factor VIII or IX deficiency can cause significant bleeding even with normal aPTT 1, 3
Do not dismiss family history as irrelevant – many patients with von Willebrand disease have affected relatives who were never formally diagnosed 4
Do not forget that von Willebrand factor is an acute phase reactant – levels can be falsely elevated during stress or illness, requiring repeated testing 4