Evaluation of Unexplained Bruising in Thin Children

Initial Clinical Assessment

• Document bruise location, number, pattern, and presence in high‑risk areas (neck, ears, buttocks, genital region, torso) because these features are highly suspicious for abuse. 1
• In children < 9 months, any bruising should raise heightened concern; infants ≤ 6 months with bruises warrant both a skeletal survey and a bleeding‑disorder work‑up. 1
• Obtain a detailed bleeding history (e.g., bleeding after circumcision, umbilical stump, minor cuts, prolonged nosebleeds, joint hemorrhages, dental procedures) to identify “classic” bleeding symptoms that trigger laboratory evaluation. 2, 3
• Record family history of known bleeding disorders and ethnic backgrounds associated with specific coagulopathies to guide suspicion for inherited conditions. 3

Decision Algorithm for Laboratory Testing

• Initiate a bleeding‑disorder work‑up when personal or family history suggests a hereditary coagulopathy. 3, 4
• Proceed with laboratory testing when the child exhibits classic bleeding manifestations such as circumcision or surgical bleeding. 2

Recommended Initial Laboratory Panel

All tests are recommended as the initial screening panel for unexplained bruising in thin children. 2, 3

Interpretation of Laboratory Results

• Normal PT and aPTT – Consider platelet‑function disorders or certain VWD subtypes; refer to pediatric hematology. 2
• Prolonged aPTT with normal PT – Suggests intrinsic‑pathway defects (hemophilia A/B, factor XI deficiency); note that mild hemophilia may have a normal aPTT. 2
• Prolonged PT with normal aPTT – Indicates factor VII deficiency or vitamin K deficiency. 2
• Both PT and aPTT prolonged – Points to combined factor deficiencies, vitamin K deficiency, or disseminated intravascular coagulation. 2

Critical Limitations and Pitfalls of the Screening Panel

• The panel does not detect:
  
  • Factor XIII deficiency (extremely rare, < 1 / 500 000). 5
  • Mild platelet‑function disorders. 2
  • Certain VWD subtypes. 2
  • Fibrinolytic defects. 2
• Common false‑positive results:
  
  • aPTT may be falsely prolonged by lupus anticoagulant or factor XII deficiency (which do not cause bleeding). 5, 4
  • Traumatic brain injury can cause transient coagulopathy unrelated to congenital disorders. 5, 4
  • Improper specimen handling frequently yields false‑positive results; testing should be performed in experienced laboratories. 5, 4

Specialist Consultation

• Pediatric hematology should be consulted when:

  • Initial coagulation studies are abnormal.
  • Clinical suspicion remains high despite normal studies.
  • Complex result interpretation is required.
  • Testing for very rare conditions (e.g., factor XIII deficiency) is considered. 3, 4

• Child‑abuse pediatrician involvement is indicated when:

  • Bruising patterns raise concern for abuse. 1, 3
  • The child is < 9 months old with any bruising. 1
  • Bruises appear in high‑risk locations (neck, ears, buttocks, genital area). 1
  • History is inconsistent or other injuries are present. 1

Skeletal Survey Indications

• Perform a skeletal survey in:
  
  • Infants < 6 months with bruising, regardless of location or explanation.
  • Children 6–24 months with bruising in suspicious locations or without an adequate trauma history.
  • Any child with patterned bruising suggestive of abuse. 1

Follow‑Up Strategy

• If a bleeding disorder is suspected but initial testing is equivocal, observe the child after removal from the home environment; bleeding disorders (except ITP) are permanent and will not resolve with caregiver changes, whereas abuse‑related bruising typically diminishes in a safe setting. 2, 3, 4
• The presence of a bleeding disorder does not exclude abuse; both conditions can coexist, and hematology follow‑up is required while maintaining vigilance for maltreatment. 3, 5, 4

Special Considerations for Transfused Patients

• Delay bleeding‑disorder screening until transfused clotting factors are cleared; factor half‑lives range from 4–6 hours (factor VII) to 144–300 hours (factor XIII). 5, 4

Guidelines for Evaluating Easy Bruising in Medically Complex Children Using Standing Devices

1. Initial Clinical Assessment

• Assess the bruising pattern and location to determine whether it matches pressure points of the standing device; if bruises are unexplained or appear in suspicious sites (neck, ears, buttocks, genital area), initiate a bleeding‑disorder work‑up with PT, aPTT, platelet count, and fibrinogen. [6][7]8
• Obtain a focused bleeding history (e.g., after circumcision, surgery, dental work, nosebleeds, or umbilical stump bleeding). [6][8]9
• Record family history of known bleeding disorders or ethnic backgrounds associated with higher prevalence of specific coagulopathies. [6][8]9
• Review all current medications and supplements that could alter coagulation testing or increase bleeding risk. [8][9]

2. Decision Points for Laboratory Evaluation

• Do not pursue a bleeding‑disorder work‑up when a clear history of trauma explains the bruising or when the pattern is unmistakably consistent with abuse. 7
• Proceed with laboratory evaluation if there is any personal or family history suggestive of a bleeding disorder. 10

3. Recommended Initial Laboratory Screening Panel

All tests should be ordered systematically in children with unexplained bruising. [10][11]

4. Interpretation Algorithm

• Normal PT and aPTT – consider platelet‑function disorders or VWD; refer to pediatric hematology. [10][11]
• Prolonged aPTT with normal PT – suggests intrinsic‑pathway defects (e.g., hemophilia, factor XI deficiency); note that mild hemophilia may have a normal aPTT yet still cause bleeding. [10][11]
• Prolonged PT with normal aPTT – suggests extrinsic‑pathway defects (e.g., factor VII deficiency, vitamin K deficiency). 11
• Both PT and aPTT prolonged – consider combined factor deficiencies or vitamin K deficiency. 11

5. Limitations of the Screening Panel

• Factor XIII deficiency (very rare, < 1 / 500 000). 11
• Mild platelet‑function disorders. 11
• Certain subtypes of VWD. 11
• Fibrinolytic defects. 11

6. Differential Diagnosis Beyond Primary Bleeding Disorders

• Ehlers‑Danlos syndrome. 9
• Vitamin C deficiency (scurvy). 9
• Malignancy or infiltrative disorders. 8
• Glutaric aciduria. 9
• Arteriovenous malformations. 9

7. Specialist Consultation

• Pediatric hematology – indicated when initial coagulation studies are abnormal, when suspicion remains high despite normal studies, or for interpretation of complex results. [10][11]
• Child‑abuse pediatrician – indicated when bruising patterns raise concern for abuse, especially if accompanied by fractures or an inconsistent history. [7][9]

8. Monitoring and Follow‑Up

• If bleeding disorders are ruled out and bruising appears related to the standing device, document the bruising pattern with photographs and reassess after adjusting the equipment. [10][11]
• Bleeding disorders are generally permanent and do not resolve with environmental changes (except transient conditions such as immune thrombocytopenia). [10][11]
• Resolution of bruising after equipment modification supports a mechanical cause rather than an underlying coagulopathy. [10][11]