When does a non-blanchable bruise become a concern?

When Non-Blanchable Bruising Becomes a Concern

A non-blanchable bruise becomes a concern immediately in any infant under 6 months of age, in non-ambulatory children regardless of age, or when located on ears, neck, trunk, buttocks, or genitals—as these patterns are highly suspicious for abuse and require urgent evaluation. 1

Age-Specific Critical Thresholds

Infants and Non-Mobile Children

• Any bruising in infants under 6 months requires immediate evaluation regardless of location or reported trauma history, as bruising in pre-mobile infants is highly suspicious for abuse and warrants skeletal survey and child protective services involvement 1, 2
• Non-ambulatory children with bruising warrant heightened concern and systematic abuse evaluation, even with a plausible trauma history 3, 1
• Bruising in infants who are not yet cruising should trigger immediate trauma evaluation concomitantly with any medical workup for bleeding disorders 3, 2

Location-Based Red Flags

• Bruising on ears, neck, trunk, buttocks, or genitals has higher specificity for abuse than bruising on bony prominences and should prompt immediate child abuse evaluation 3, 1
• Patterned bruising (showing the shape of an object or hand) is pathognomonic for inflicted injury and requires immediate reporting 1
• Bruising in unusual locations in any age group suggests either abuse or an underlying bleeding disorder requiring investigation 1, 4

Medical Conditions Requiring Urgent Evaluation

Bleeding Disorders

• Von Willebrand disease and Factor XIII deficiency are not detected by standard PT/aPTT screening, making them critical considerations when unexplained bruising occurs with normal initial coagulation studies 1, 4
• Easy bruising with petechiae, mucosal bleeding, or family history of bleeding disorders requires hematology evaluation for platelet function disorders, hemophilia, or von Willebrand disease 4
• Normal PT/aPTT does not exclude bleeding disorders; specialized testing including VWF antigen, VWF ristocetin cofactor activity, and platelet function studies may be necessary 1, 4

Systemic Disease Indicators

• Bruising accompanied by fever, malaise, or systemic symptoms may indicate Stevens-Johnson syndrome/toxic epidermal necrolysis, where purpuric macules and non-blanchable lesions precede epidermal necrolysis 3
• Multiple bruises of different ages suggest either repeated trauma (abuse) or an evolving coagulopathy requiring immediate laboratory evaluation 3
• Ehlers-Danlos syndrome should be considered when easy bruising occurs with joint hypermobility, skin hyperextensibility, or family history of connective tissue disorders 1, 5

Differential Diagnosis Requiring Immediate Attention

Distinguishing Bruising from Other Conditions

• Deep tissue injury can present as purple or maroon non-blanchable discoloration with defined borders, particularly in patients with recent immobility or "time down" events, and must be distinguished from bruising 6
• Stage I pressure injuries present as non-blanchable erythema in patients with pressure exposure history, requiring assessment for underlying tissue damage 3, 6
• In dark-skinned patients, persistent hyperpigmentation rather than blanching should be used to determine pressure injury versus bruising 6

Life-Threatening Mimics

• Purpuric macules that are tender to touch with positive Nikolsky sign suggest Stevens-Johnson syndrome/toxic epidermal necrolysis, requiring immediate hospitalization 3
• Non-blanchable purpura with fever and systemic illness may indicate meningococcemia, disseminated intravascular coagulation, or vasculitis requiring emergency intervention 4

Systematic Evaluation Protocol

Immediate Assessment Steps

• Complete medication review including NSAIDs, anticoagulants, antiplatelet agents, corticosteroids, and supplements is essential, as these commonly cause easy bruising 1, 4
• Document bruise pattern, location, size, and color; photograph if possible for medicolegal documentation 3, 1
• Assess for additional injuries on complete skin examination, as bruises are the most common injury in child abuse but may be accompanied by fractures or other trauma 3

Laboratory Evaluation When Indicated

• Initial screening: complete blood count with platelet count, PT, aPTT, and fibrinogen level 1, 4
• If PT/aPTT are normal but clinical suspicion remains high, proceed with VWD-specific testing including VWF antigen, VWF ristocetin cofactor activity, and Factor VIII coagulant activity 4
• Consider liver function tests, vitamin K level, and Factor XIII assay if initial screening is abnormal or clinical picture suggests these deficiencies 1, 4

Mandatory Skeletal Survey Indications in Children

• Skeletal survey is required for children under 24 months with bruising when there is witnessed or confessed abuse, domestic violence history, additional injuries on examination, patterned bruising, or age under 6 months 1
• Additional fractures are identified in approximately 10% of skeletal surveys, with higher yields in infants 3

Critical Pitfalls to Avoid

• Never accept implausible trauma explanations in children; delay in seeking care for an injury is itself suspicious for abuse 3, 1
• Do not perform extensive bleeding disorder testing without clinical indication in children when abuse is suspected; pursue both evaluations simultaneously rather than sequentially 1, 2
• Avoid assuming that absence of bruising at a fracture site excludes abuse, as the majority of children with abusive fractures do not have associated bruising 3
• Do not rely solely on PT/aPTT to exclude bleeding disorders, as these tests miss von Willebrand disease, Factor XIII deficiency, and platelet function disorders 1, 4

Referral Indications

• Immediate child abuse pediatrician consultation for any suspected abuse case 1
• Hematology referral when abnormal initial laboratory results occur, high clinical suspicion exists with normal laboratory workup, or specialized testing (platelet aggregation studies, VWD multimer analysis) is needed 1, 4
• Dermatology consultation when differential diagnosis includes Stevens-Johnson syndrome/toxic epidermal necrolysis, vasculitis, or other dermatologic conditions mimicking bruising 3, 6