Overview

Definition:
-Fever and petechiae in children are alarming signs requiring urgent differentiation between life-threatening meningococcemia (a form of bacterial sepsis) and a more benign, though still significant, hematological disorder, Idiopathic Thrombocytopenic Purpura (ITP)
-Meningococcemia is caused by Neisseria meningitidis and can rapidly progress to disseminated intravascular coagulation (DIC) and shock
-ITP is an autoimmune disorder characterized by isolated thrombocytopenia and a tendency for bleeding, typically without fever or signs of systemic infection unless a co-existing viral illness is present.
Epidemiology:
-Meningococcemia is rare but has a high mortality rate
-incidence varies geographically but is more common in unvaccinated populations and during outbreaks
-Peak incidence is in infants and young children
-ITP is the most common acquired bleeding disorder in children, with an incidence of 2-8 cases per 100,000 children per year
-It can occur at any age but is most common between 2-6 years, with a bimodal distribution (post-viral in younger children, bimodal again in adolescents/adults).
Clinical Significance:
-Prompt and accurate diagnosis is paramount
-Delay in recognizing meningococcemia can lead to rapid deterioration and death
-Conversely, misdiagnosing ITP as meningococcemia can lead to unnecessary aggressive antibiotic therapy and inpatient admission
-Understanding the distinct clinical features, diagnostic workup, and management strategies is crucial for pediatric residents preparing for DNB and NEET SS examinations.

Clinical Presentation

Symptoms:
-Fever is common in both
-Meningococcemia: sudden onset of high fever, headache, stiff neck, vomiting, photophobia, lethargy, irritability, myalgias
-Petechiae often appear rapidly and may coalesce into purpura
-ITP: bleeding manifestations are primary – epistaxis, gum bleeding, petechiae, purpura, menorrhagia, hematuria, melena
-Fever is usually absent or low-grade, often preceding rash by days and related to a preceding viral illness.
Signs:
-Meningococcemia: ill-appearing child, signs of meningitis or sepsis, characteristic petechial or purpuric rash (can be widespread, non-blanching)
-Tachycardia, hypotension
-Signs of shock or DIC (e.g., organ dysfunction)
-ITP: normal or mildly febrile child, isolated petechiae and purpura, normal vital signs
-Examination for signs of systemic infection should be negative
-Lymphadenopathy and splenomegaly are typically absent in acute ITP.
Diagnostic Criteria:
-Meningococcemia: Clinical suspicion confirmed by positive blood culture for Neisseria meningitidis
-Presence of fever, petechial/purpuric rash, and meningeal signs or sepsis are highly suggestive
-ITP: Diagnosis of exclusion based on isolated thrombocytopenia (platelet count < 100,000/µL) in an otherwise healthy child with normal coagulation studies and no other identifiable cause of thrombocytopenia
-Absence of fever and signs of systemic infection is key.

Diagnostic Approach

History Taking:
-Recent travel or exposure to known cases of meningococcal disease
-Vaccination status (Hib, MenACWY, MenB)
-Prodromal viral illness (URI, gastroenteritis) preceding rash by days to weeks
-History of recent blood transfusions or medications
-Family history of bleeding disorders or autoimmune conditions
-Trauma or recent procedures
-Use of NSAIDs or aspirin
-Red flags: rapid onset of rash, high fever, lethargy, purpura fulminans.
Physical Examination:
-Thorough assessment for signs of sepsis (toxic appearance, hypotension, tachycardia)
-Careful examination of the skin for blanching vs non-blanching lesions
-distribution and morphology of petechiae/purpura
-Neurological examination for meningeal signs
-Examination for source of infection (e.g., otitis, pneumonia, cellulitis)
-Assess for bleeding from other sites.
Investigations:
-Meningococcemia: Blood culture (essential, before antibiotics if possible)
-Complete blood count (CBC) with differential (may show leukocytosis, but can be normal or low in overwhelming sepsis)
-Coagulation profile (PT, aPTT, INR, fibrinogen, D-dimer) to assess for DIC
-Lumbar puncture if meningitis is suspected (CSF analysis for pleocytosis, Gram stain, culture)
-Polymerase chain reaction (PCR) for Neisseria meningitidis in blood or CSF
-ITP: CBC with differential (platelet count < 100,000/µL, often < 20,000/µL
-WBC and Hgb typically normal)
-Peripheral blood smear (confirm thrombocytopenia, exclude pseudo-thrombocytopenia or other red cell abnormalities)
-Coagulation profile (PT, aPTT, INR, fibrinogen, D-dimer) to rule out DIC
-Liver function tests (LFTs) and renal function tests (RFTs)
-Serology for viral causes of thrombocytopenia (e.g., EBV, CMV, parvovirus B19) if indicated
-Bone marrow aspirate and biopsy typically not needed in acute childhood ITP but may be considered in chronic or atypical cases.
Differential Diagnosis:
-Other causes of fever and petechiae/purpura: Viral exanthems with thrombocytopenia (e.g., dengue fever, enteroviruses)
-Rocky Mountain spotted fever (RMSF) and other tick-borne illnesses
-Hemolytic Uremic Syndrome (HUS)
-Henoch-Schönlein Purpura (HSP) – typically rash is palpable and urticarial/purpuric, often associated with abdominal pain and arthritis
-Leukemia or other hematological malignancies
-Drug-induced thrombocytopenia
-Disseminated intravascular coagulation (DIC) from any cause
-Other bacterial sepsis with rash (e.g., Staphylococcus aureus, Streptococcus pyogenes).

Management

Initial Management:
-Meningococcemia: IMMEDIATE broad-spectrum IV antibiotics (e.g., Ceftriaxone 100 mg/kg/dose IV q12h, or Cefotaxime) should be started empirically if meningococcemia is suspected, even before culture results or definitive diagnosis, after blood cultures are obtained
-Fluid resuscitation for shock
-Close monitoring in an intensive care setting
-ITP: If platelet count > 30,000/µL and no significant bleeding, observe
-If platelet count < 30,000/µL or bleeding, consider treatment
-Steroids (e.g., Prednisolone 1-2 mg/kg/day orally or IV) or IV Immunoglobulin (IVIG) (1 g/kg/day IV for 1-2 days).
Medical Management:
-Meningococcemia: Continue IV antibiotics for at least 7-10 days, tailored to culture and sensitivity results
-Prophylaxis for close contacts with Rifampin, Ciprofloxacin, or Ceftriaxone
-ITP: Steroids (prednisolone, dexamethasone) or IVIG are first-line
-Platelet transfusions are reserved for active, severe bleeding or very low platelet counts (< 10,000/µL) in conjunction with other therapies.
Surgical Management:
-Not typically indicated for primary meningococcemia or ITP
-Surgery may be required for complications like limb ischemia or tissue necrosis due to purpura fulminans in meningococcemia, or in rare cases of splenectomy for refractory ITP.
Supportive Care:
-Meningococcemia: Aggressive supportive care including fluid management, vasopressors if needed, mechanical ventilation, management of DIC and organ failure
-Close monitoring of vital signs, urine output, and neurological status
-ITP: Strict avoidance of aspirin and NSAIDs
-Education on signs of bleeding
-Monitoring for recurrence.

Complications

Early Complications:
-Meningococcemia: Purpura fulminans, DIC, shock, adrenal hemorrhage (Waterhouse-Friderichsen syndrome), myocarditis, arthritis, meningitis, encephalitis, limb loss, death
-ITP: Significant bleeding (intracranial hemorrhage is rare but serious), prolonged disease course, anemia due to chronic blood loss.
Late Complications:
-Meningococcemia: Neurological deficits, hearing loss, limb deformities, scarring
-ITP: Chronic ITP (persists > 12 months), increased risk of bleeding with minor trauma or surgery.
Prevention Strategies:
-Meningococcemia: Vaccination against Neisseria meningitidis (especially serogroups A, C, Y, W-135, and B)
-Prompt diagnosis and treatment of cases
-Chemoprophylaxis for close contacts
-ITP: No specific prevention
-Focus on early recognition and management to prevent severe bleeding.

Prognosis

Factors Affecting Prognosis:
-Meningococcemia: Rapid diagnosis and initiation of antibiotics are the most critical factors
-Severity of illness at presentation (shock, DIC), age, and virulence of the infecting strain
-ITP: Most children (80-85%) achieve spontaneous remission within 6-12 months
-Factors associated with chronic ITP include older age at diagnosis and certain viral infections
-Severe bleeding events significantly impact short-term outcome.
Outcomes:
-Meningococcemia: Mortality rates have decreased with prompt treatment but remain significant (5-15% in developed countries)
-Survivors may have long-term sequelae
-ITP: Excellent prognosis for spontaneous recovery in most children
-Chronic ITP requires long-term management.
Follow Up:
-Meningococcemia survivors: Regular follow-up for neurological, audiological, and dermatological assessment
-ITP: Regular monitoring of platelet counts, especially during the first year
-Education for parents regarding signs of bleeding and when to seek medical attention
-Annual review for chronic ITP.

Key Points

Exam Focus:
-Distinguishing fever/petechiae in pediatric emergencies
-Meningococcemia = SEPSIS + RASH
-ITP = THROMBOCYTOPENIA + BLEEDING (usually NO fever/sepsis)
-Always consider meningococcemia in febrile child with petechiae
-start antibiotics empirically AFTER blood culture
-ITP management is based on platelet count and bleeding severity, not solely platelet count.
Clinical Pearls:
-A non-blanching petechial or purpuric rash in a febrile child is a medical emergency until proven otherwise
-NEVER delay antibiotics for suspected meningococcemia while waiting for investigations
-In ITP, look for bleeding, not infection
-Lumbar puncture is contraindicated if signs of increased intracranial pressure or signs of DIC with purpura fulminans.
Common Mistakes:
-Delaying empirical antibiotics in suspected meningococcemia due to fear of masking fever
-Misdiagnosing meningococcemia as viral exanthem or ITP
-Aggressively treating ITP with steroids/IVIG when observation is sufficient (platelets > 30k and no bleeding)
-Failing to perform blood cultures before starting antibiotics for suspected meningococcemia.