Overview
Definition:
Idiopathic Thrombocytopenic Purpura (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia (low platelet count) in the absence of other identifiable causes, leading to increased risk of bleeding.
Epidemiology:
It is the most common acquired bleeding disorder in children
Acute ITP typically affects children aged 2-10 years, with a slight male predominance
Incidence is estimated at 1-3 per 100,000 children per year
Chronic ITP is less common in childhood and more prevalent in adults.
Clinical Significance:
ITP is significant due to the potential for severe bleeding, especially intracranial hemorrhage, though rare
Understanding management strategies is crucial for preventing complications and distinguishing it from other causes of thrombocytopenia, a common scenario in pediatric emergency and outpatient settings relevant for DNB and NEET SS exams.
Clinical Presentation
Symptoms:
Often asymptomatic with incidental finding of low platelets
Easy bruising (purpura)
Petechiae, especially on dependent areas or pressure points
Bleeding from gums or nose (epistaxis)
Hematuria or menorrhagia in older girls
Rarely, signs of internal hemorrhage such as abdominal pain or neurological symptoms.
Signs:
Isolated thrombocytopenia (<100,000/µL) on complete blood count
Normal or slightly enlarged spleen
Absence of fever or signs of infection (unless concurrent)
Examination for other signs of bleeding (e.g., conjunctival petechiae, hematoma formation)
Absence of hepatosplenomegaly or lymphadenopathy, which would suggest other causes.
Diagnostic Criteria:
Diagnosis is primarily clinical and laboratory-based
Key criteria include: isolated thrombocytopenia
absence of splenomegaly (usually)
normal white blood cell and red blood cell counts
absence of other causes of thrombocytopenia (e.g., leukemia, sepsis, drug-induced thrombocytopenia, inherited disorders)
Platelet count < 150,000/µL with documentation of the diagnosis and exclusion of other causes.
Diagnostic Approach
History Taking:
Detailed history of bleeding onset and duration
Recent viral illness or vaccination (within 2-4 weeks) preceding acute ITP
Family history of bleeding disorders
Medication history (e.g., aspirin, NSAIDs, certain antibiotics)
Inquiry about symptoms suggestive of systemic illness or malignancy
Assess for any signs of recent trauma.
Physical Examination:
Thorough skin examination for petechiae, purpura, ecchymoses
Palpate abdomen for splenomegaly
Examine for mucosal bleeding (oral, nasal)
Assess for any signs of neurological deficit
Evaluate lymph nodes for enlargement
Look for signs of sepsis or systemic infection.
Investigations:
Complete blood count (CBC) with differential and platelet count is essential, showing isolated thrombocytopenia
Peripheral blood smear examination is critical to rule out pseudothrombocytopenia and assess platelet morphology, looking for normal-sized platelets
Coagulation profile (PT, aPTT) should be normal
Bone marrow aspiration and biopsy is generally not indicated in typical cases of acute ITP in children but may be considered in refractory cases, atypical presentations, or if a secondary cause is suspected
Serological tests for infections like HIV, HCV, H
pylori are generally not recommended in routine childhood acute ITP.
Differential Diagnosis:
Other causes of thrombocytopenia: Acute leukemia (look for abnormal blast cells, pancytopenia)
Sepsis (look for fever, signs of infection, coagulopathy)
Viral infections (e.g., EBV, CMV causing secondary thrombocytopenia)
Drug-induced thrombocytopenia
Inherited platelet disorders
Systemic lupus erythematosus (SLE) or other autoimmune disorders
Hemolytic Uremic Syndrome (HUS) (look for anemia, renal dysfunction, schistocytes)
Pseudothrombocytopenia (platelet satellitism on EDTA tube)
Congenital amegakaryocytic thrombocytopenia.
Management
Initial Management:
For mild to moderate ITP (platelet count > 20,000-30,000/µL with no significant bleeding), observation may be the initial approach
Avoid trauma and contact sports
Educate parents on signs of bleeding requiring immediate medical attention.
Medical Management:
Treatment is indicated for symptomatic bleeding or very low platelet counts (<10,000-20,000/µL)
Options include: Intravenous Immunoglobulin (IVIG) 1 g/kg/day for 1-2 days or 0.8 g/kg/day for 2 days
Corticosteroids (e.g., Prednisolone 1-2 mg/kg/day orally or Dexamethasone pulses)
These treatments aim to rapidly increase platelet count by reducing platelet destruction or increasing production
Rituximab is an option for refractory chronic ITP
Thrombopoietin receptor agonists (e.g., Eltrombopag) are generally reserved for chronic refractory ITP in older children or adults.
Surgical Management:
Splenectomy is rarely indicated in childhood ITP and is reserved for cases of chronic refractory ITP that have failed multiple medical therapies, usually after puberty
It is not a first-line treatment.
Supportive Care:
Close monitoring of platelet counts and signs of bleeding
Parental education on disease course and management
Strict avoidance of NSAIDs and aspirin due to their antiplatelet effects
Prompt attention to any significant bleeding episodes
Counseling on activity restrictions.
Observation Vs Treatment Strategy
Observation Strategy:
Observation is suitable for asymptomatic children with platelet counts > 20,000-30,000/µL
In most cases of acute childhood ITP, spontaneous remission occurs within weeks to months
This approach minimizes exposure to side effects of medications.
Treatment Indications:
Treatment is generally recommended for children with platelet counts < 10,000-20,000/µL, or any child with bleeding (mucosal bleeding, petechiae beyond a few mm, purpura, ecchymoses)
Severe bleeding (e.g., gastrointestinal, genitourinary, intracranial) requires urgent intervention regardless of platelet count.
Ivig Role:
IVIG is effective in rapidly increasing platelet counts, making it useful for managing acute, significant bleeding or to achieve a higher platelet count for procedures
Its effect is transient, typically lasting a few weeks
Dose: 1 g/kg/day for 1-2 days or 0.8 g/kg/day for 2 days.
Steroid Role:
Corticosteroids, such as oral prednisolone (1-2 mg/kg/day), are also effective in increasing platelet counts and are often used as a first-line treatment for symptomatic ITP
They can induce longer remissions compared to IVIG but have more systemic side effects with prolonged use
Dexamethasone pulse therapy (e.g., 0.6 mg/kg/day for 4 days) is also an option.
Complications
Early Complications:
Severe bleeding (e.g., intracranial hemorrhage, gastrointestinal bleeding, prolonged epistaxis)
Anemia due to blood loss
Side effects from medications (e.g., allergic reactions to IVIG, hyperglycemia, mood changes, increased infection risk with steroids).
Late Complications:
Development of chronic ITP (>12 months duration), which is less common in children than acute ITP
Psychological impact on child and family
Long-term effects of steroid therapy if used repeatedly or for extended periods (e.g., growth retardation, Cushingoid features).
Prevention Strategies:
Careful monitoring for bleeding
Prompt initiation of treatment when indicated
Patient and family education on avoiding trauma and recognizing bleeding symptoms
Judicious use of medications and monitoring for their side effects
Avoiding unnecessary invasive procedures in patients with severe thrombocytopenia.
Prognosis
Factors Affecting Prognosis:
Most children (about 80%) with acute ITP achieve spontaneous remission within 6 months
Factors associated with chronic ITP include older age at diagnosis, very low initial platelet counts, and presence of specific autoantibodies
Severity of initial bleeding can be a factor.
Outcomes:
The prognosis for acute childhood ITP is generally excellent, with the vast majority recovering fully
Chronic ITP, while less common, can require long-term management and may impact quality of life.
Follow Up:
Children with acute ITP who recover generally do not require long-term follow-up once platelet counts normalize and bleeding resolves
Those who develop chronic ITP require regular monitoring by a pediatric hematologist, including platelet counts and assessment for bleeding and medication-related side effects.
Key Points
Exam Focus:
DNB/NEET SS frequently test the distinction between acute and chronic ITP in children, indications for treatment (bleeding vs
platelet count), first-line agents (IVIG/Steroids), and distinguishing ITP from other causes of thrombocytopenia
Remember that bone marrow biopsy is NOT routinely needed in children with typical ITP presentation.
Clinical Pearls:
Always consider concurrent viral illness or recent vaccination in the history of acute ITP
A peripheral blood smear is crucial to rule out pseudothrombocytopenia and assess platelet size
Observe asymptomatic children with platelet counts >20-30k/µL
Treat symptomatic children or those with counts <10-20k/µL
IVIG offers rapid but transient platelet elevation
steroids offer sustained increase but with more side effects.
Common Mistakes:
Over-treating asymptomatic children with low platelet counts
Failing to consider other causes of thrombocytopenia in atypical presentations (e.g., child with fever and petechiae and abnormal WBC)
Delaying treatment in children with significant bleeding
Relying solely on platelet count without assessing bleeding status for treatment decisions
Ordering unnecessary investigations like bone marrow aspiration in routine acute ITP.