Child With Petechiae/Purpura

Definitions

• Petechiae: Non-blanching erythematous skin lesions (usually 2mm-5mm) due to extravasation of blood from intradermal capillary leak

• Purpura: Larger lesions which may or may not be palpable

DDx

• Infection

  • Bacterial

    • Meningococcemia

    • Streptococcus

    • H influenzae

    • Infective endocarditis

  • Viral

    • Parvovirus - glove-socks distribution, may be associated with slapped cheek syndrome

    • Rockey Mountain Spotted Fever in North america

    • Epidemic typhus, Queensland tick typhus

• Mechanical

  • Cough/vomiting (limited to head and neck)

  • Local pressure/tourniquet (distal to tourniquet)

  • Strangulation

• Hematological

  • Thrombocytopenia (Plat <100)

    • ITP - likely diagnosis if otherwise normal CBC and no hepatosplenomegaly, or lymphadenopathy

    • Leukemia

    • Hypersplenism

  • Vascular

    • Vasculitis - Henoch-Schonlein purpura HSP

    • Scurvy (perifollicular purpura on lower limbs)

    • Drugs - steroids

    • Cushing's syndrome

    • Fat embolism

    • Dysproteinemia

History and Physical

• Rule out serious bacterial illness (sepsis, meningitis)

Management

• If mechanical cause suspected, reassurance and manage underlying condition

• If non-mechanical cause

  • CBC, CRP, blood culture

  • Consider INR

  • Observe child for 4 hours in ED

    • Discharge if well, petechiae do not progress, and labs reassuring (CRP <8, WBC 5-15)

• If unwell (irritable, lethargic, abnormal vital signs, poor peripheral circulation)

  • ABC

  • Fluid resuscitation

  • Third generation cephalosoprin (ceftriaxone, cefotaxime)

  • Admit

Henoch-Schönlein Purpura (HSP)

• Common vasculitis in children 2-8yo

• Diagnosis

  • Palpable purpura without thrombocytopenia/coagulopathy, and with one of

    • Arthritis (acute, any joint) or arthralgia (50-75%)

    • Diffuse abdominal pain (50%)

    • Renal involvement (any hematuria or proteinuria) (25-50%)

    • Biopsy-proven (immunoglobulin A deposition)

• Physical Exam

  • Blood pressure (r/o Hypertension)

  • Height/Weight (to calcualte normal BP based on sex/age/height/weight)

  • Palpable purpura, petechiae

  • Painful subcutaneous edema (periorbital, hands, feet, scrotum)

  • Joint exam (usually no significant effusion/warmth)

  • Abdomen (rule out obstruction, intussussception)

  • Resp (rule out hemorrhage)

  • Neuro

• Labs

  • CBC with platelets

  • UA (hematuria, proteinuria)

  • Renal function (lytes, BUN, creat, UA)

  • Consider blood cultures, Coags

  • Consider throat swab, ASOT (if current/recent sore throat)

  • May consider IgA (elevated)

• Imaging

  • If severe abdominal pain, consider Ultrasound r/o intussusception

  • If severe scrotal symptoms, consider Doppler r/o testicular torsion

• Complications

  • Renal (glomerulonephritis, renal failure)

  • Orchitis, scrotal swelling (may cause torsion)

  • CNS involvement (seizure, hemorrhage)

  • Other

    • Intussusception

    • Myocardial infarction

    • Pulmonary hemorrhage

• Management

  • Supportive

    • Acetaminophen

    • NSAIDs (avoid if renal involvement), eg. Naproxen 10-20mg/kg divided BID (max 500mg BID)

  • Counselling

    • >90% resolve spontaneously within 4w

    • Joint pain and abdominal pain resolve within 2-3d

    • HSP recurs at least once in 25-35% of patients (usually milder)

    • Advise that purpura may recur as they increase activity

  • Consider

    • Admission for dehydration, hemorrhage, pain control

    • Nephrology consultation if significant renal failure, hypertension, persistent renal involvement

    • Steroids for severe abdominal or joint pain

      • Prednisone 1-2mg/kg daily (max 60mg daily) x 2 weeks, taper 25% per week

        • Caution as may mask signs/symptoms of complications

  • Follow-up (repeat follow-up if flare)

    • Home urine dipstick weekly x 1 month

    • BP and UA monthly or q2 months until 1 year

      • Serum BUN and creat if hematuria or proteinura

      • Refer patients with persistent hematuria, proteinuria, hypertension, renal insufficiency

Immune thrombocytopenia (ITP)

• Diagnosis

  • Sudden petechiael rash/brusing in well child

    • Platelet <100, otherwise normal CBC/reticulocyte

    • Normal blood smear (no hemolysis, blasts)

    • Negative DAT (Coombs)

    • Negative history/physical examination (no lymphadenopathy, hepatosplenomegaly, systemic symptoms eg. fever, weight loss, family history)

• Investigations

  • CBC, platelet

  • Reticulocytes

  • Peripheral blood smear

  • Blood type and direct antiglobulin test (DAT, formerly Coombs)

• Management

  • Consider Hematology consultation

  • Provide safe platelet count to avoid important bleeding

    • Severe bleeding or platelet <30 should get platelet transfusion with IVIG and glucocorticoids (with hematology consultation)

  • If no bleeding and platelet >30, observe as no treatment usually required