NCLEX Review Guide: Pediatric Meningitis

Definition and Classification

• Meningitis is an inflammation of the meninges, the protective membranes covering the brain and spinal cord. In children, it can be caused by bacterial, viral, or fungal pathogens that invade the subarachnoid space and cerebrospinal fluid (CSF).
• Classification includes bacterial meningitis (most severe form), viral meningitis (generally less severe), and fungal meningitis (rare in immunocompetent children).

Common Causative Organisms

• Neisseria meningitidis: A leading cause of bacterial meningitis in children and adolescents, particularly in community outbreaks.
• Streptococcus pneumoniae: Common in infants and children, especially those with cochlear implants or immunodeficiencies.
• Haemophilus influenzae type b (Hib): Less common due to vaccination but still seen in unvaccinated children.
• Group B Streptococcus: Primary cause in neonates (0-3 months), transmitted during childbirth.
• Enteroviruses: Most common cause of viral meningitis in children, particularly during summer and fall.

Risk Factors

• Age-related vulnerability: Highest incidence in children under 5 years, with a second peak in adolescents.
• Incomplete vaccination status increases risk for vaccine-preventable forms of meningitis.
• Immunocompromised states, including HIV, malignancies, or congenital immunodeficiencies.
• Anatomic abnormalities such as CSF leaks, cochlear implants, or neural tube defects.
• Recent close contact with individuals diagnosed with meningitis, particularly in daycare or school settings.

Classic Signs and Symptoms

• Fever: Usually high-grade (>38.5°C or 101.3°F), often with sudden onset in bacterial meningitis.
• Nuchal rigidity: Stiff neck with resistance to passive flexion, a classic meningeal sign.
• Headache: Often severe, frontal or generalized, worsened by bright lights or loud sounds.
• Altered mental status: Ranging from irritability and lethargy to confusion and coma.
• Vomiting: Often projectile, not necessarily related to food intake.
• Photophobia: Sensitivity to light, more common in older children who can verbalize this symptom.

Age-Specific Presentations

• Neonates (0-1 month): May present with nonspecific symptoms including poor feeding, irritability, lethargy, temperature instability (hypothermia or hyperthermia), bulging fontanelle, and seizures. Classic meningeal signs are often absent.
• Infants (1-12 months): May display irritability, poor feeding, high-pitched cry, bulging fontanelle, and seizures. Nuchal rigidity may be difficult to assess.
• Toddlers and young children: More likely to exhibit classic symptoms but may have difficulty articulating complaints like headache.
• School-age and adolescents: Typically present with the classic triad and can better communicate subjective symptoms.

Meningeal Signs

• Kernig's sign: With the patient lying supine and hip flexed at 90°, pain and resistance occur with knee extension, indicating meningeal irritation.
• Brudzinski's sign: Involuntary flexion of the knees and hips when the neck is passively flexed while the patient is supine.
• Tripod position: Child sits with neck hyperextended and weight supported on hands behind the back to reduce meningeal tension.

Complications and Severe Presentations

• Increased intracranial pressure (ICP): Manifests as bulging fontanelle in infants, severe headache, vomiting, altered mental status, papilledema, and abnormal posturing.
• Seizures: May occur in up to 30% of children with bacterial meningitis, indicating severe disease.
• Meningococcemia: Characterized by purpuric or petechial rash, disseminated intravascular coagulation (DIC), and shock.
• Subdural effusions: Collection of fluid between the dura and arachnoid membranes, more common in infants.
• Hydrocephalus: May develop as an acute or chronic complication due to impaired CSF circulation.

Diagnostic Procedures

1. Perform comprehensive physical assessment, including vital signs, neurological assessment, and examination for meningeal signs.
2. Obtain blood cultures before antibiotic administration to identify causative organism.
3. Perform lumbar puncture (LP) for CSF analysis, the definitive diagnostic test for meningitis.
4. Collect CSF samples for cell count, glucose, protein, culture, Gram stain, and potentially PCR testing.
5. Consider neuroimaging (CT or MRI) before LP if there are signs of increased ICP or focal neurological deficits.

CSF Analysis Interpretation

Additional Diagnostic Studies

• Complete Blood Count (CBC): Often shows leukocytosis with left shift in bacterial meningitis; may be normal in viral meningitis.
• C-Reactive Protein (CRP) and Procalcitonin: Inflammatory markers that are typically elevated in bacterial infections.
• Serum Electrolytes: To assess for syndrome of inappropriate antidiuretic hormone (SIADH) or cerebral salt wasting.
• Coagulation Studies: To assess for DIC, particularly in meningococcemia.
• Neuroimaging: CT or MRI to identify complications such as brain abscess, subdural effusions, hydrocephalus, or cerebral edema.

Emergency Management

1. Assess ABCs (Airway, Breathing, Circulation) and stabilize as needed.
2. Obtain vascular access immediately for fluid resuscitation and medication administration.
3. Collect blood cultures before antibiotic administration when possible.
4. Administer empiric antibiotics within 30-60 minutes of presentation for suspected bacterial meningitis.
5. Implement isolation precautions, particularly for suspected meningococcal or Hib meningitis.
6. Monitor vital signs, neurological status, and fluid balance continuously.

Antimicrobial Therapy

• Empiric therapy is based on age and likely pathogens:
  • Neonates (0-1 month): Ampicillin plus cefotaxime or gentamicin
  • Infants/Children (1 month-5 years): Ceftriaxone or cefotaxime plus vancomycin
  • Older children/Adolescents: Ceftriaxone or cefotaxime plus vancomycin
• Therapy duration: Typically 7-10 days for most bacterial pathogens; longer for certain organisms (e.g., Gram-negative bacilli, Listeria).
• Viral meningitis: Supportive care is the mainstay; specific antivirals (e.g., acyclovir) if herpes virus is suspected.

Adjunctive Therapy

• Dexamethasone: May be administered before or with the first dose of antibiotics in suspected bacterial meningitis to reduce inflammation and complications, particularly hearing loss in Hib meningitis.
• Seizure management: Anticonvulsants for active seizures; prophylactic anticonvulsants are not routinely recommended.
• ICP management: Head elevation, minimal stimulation, osmotic agents (mannitol, hypertonic saline), and potential neurosurgical intervention for severe cases.
• Fluid management: Careful monitoring for SIADH; fluid restriction may be necessary but avoid dehydration.

Nursing Management

• Neurological monitoring: Perform frequent neurological assessments, including level of consciousness, pupillary responses, and signs of increased ICP.
• Vital signs monitoring: Assess temperature, heart rate, respiratory rate, blood pressure, and oxygen saturation every 1-4 hours based on condition.
• Infection control: Implement appropriate isolation precautions based on suspected pathogen.
• Pain and comfort management: Administer analgesics for headache and discomfort; maintain a quiet, dimly lit environment for photophobia.
• Fluid and electrolyte balance: Monitor intake and output, daily weights, and serum electrolytes.

Vaccination

• Haemophilus influenzae type b (Hib) vaccine: Routine childhood immunization that has dramatically reduced Hib meningitis incidence.
• Pneumococcal conjugate vaccine (PCV13): Protects against 13 serotypes of pneumococcus that commonly cause invasive disease.
• Pneumococcal polysaccharide vaccine (PPSV23): Recommended for children ≥2 years with high-risk conditions.
• Meningococcal conjugate vaccine (MenACWY): Recommended for adolescents at age 11-12 with a booster at age 16, and for high-risk children.
• Meningococcal B vaccine (MenB): Considered for adolescents and young adults, especially during outbreaks.

Chemoprophylaxis

• Close contacts of patients with meningococcal or Hib meningitis should receive chemoprophylaxis to prevent secondary cases.
• For meningococcal exposure, rifampin, ciprofloxacin, or ceftriaxone are recommended prophylactic agents.
• For Hib exposure, rifampin is recommended for household contacts if there are unvaccinated or incompletely vaccinated children under 4 years in the household.
• Healthcare workers need prophylaxis only if they had intensive, unprotected contact with respiratory secretions.

Patient and Family Education

• Discharge instructions: Provide written information about medication administration, follow-up appointments, and signs of complications.
• Return precautions: Instruct families to seek immediate medical attention for fever, headache, vomiting, seizures, or altered mental status after discharge.
• Prevention education: Emphasize the importance of completing the recommended vaccination schedule.
• Long-term follow-up: Explain the need for audiological and neurodevelopmental follow-up after bacterial meningitis.

Acute Complications

• Cerebral edema and increased ICP: Can lead to herniation, a life-threatening emergency.
• Seizures: Occur in up to 30% of children with bacterial meningitis.
• Subdural effusions: More common in infants, may require surgical drainage if causing mass effect.
• Hydrocephalus: Due to impaired CSF circulation or absorption.
• SIADH: Inappropriate ADH secretion leading to hyponatremia.
• Septic shock: Particularly in meningococcemia, requiring aggressive fluid resuscitation and vasopressors.

Long-term Sequelae

• Hearing loss: Occurs in 5-30% of children after bacterial meningitis, particularly with pneumococcal etiology.
• Neurological deficits: Including cognitive impairment, motor deficits, visual impairment, and behavioral changes.
• Seizure disorders: Development of epilepsy after meningitis.
• Learning disabilities: May become apparent as the child reaches school age.
• Psychological effects: Including post-traumatic stress, anxiety, and adjustment difficulties.

Prognosis Factors

• Favorable prognostic factors: Early diagnosis and treatment, viral etiology, absence of seizures, normal mental status at presentation, and absence of comorbidities.
• Unfavorable prognostic factors: Young age (especially neonates), delayed treatment, pneumococcal etiology, seizures, altered consciousness at presentation, and presence of shock or DIC.

Critical Concepts

• Bacterial meningitis is a medical emergency requiring immediate recognition and treatment to prevent mortality and long-term sequelae.
• Clinical presentation varies by age, with infants often presenting with nonspecific symptoms and without classic meningeal signs.
• Lumbar puncture with CSF analysis is the definitive diagnostic test, but treatment should not be delayed to obtain CSF if bacterial meningitis is suspected.
• Empiric antibiotic therapy should be age-appropriate and cover the most likely pathogens based on the child's age and risk factors.
• Dexamethasone may reduce inflammatory complications when given before or with the first dose of antibiotics.
• Vaccination remains the most effective preventive strategy against bacterial meningitis.

Commonly Confused Points

Study Tips

Knowledge Checklist

• I can describe the pathophysiology of meningitis and differentiate between bacterial and viral etiologies.
• I can identify age-specific clinical presentations of meningitis in children.
• I can interpret CSF findings to distinguish between bacterial and viral meningitis.
• I understand the emergency management of suspected bacterial meningitis.
• I can identify appropriate empiric antibiotic therapy based on age and likely pathogens.
• I know the indications and timing for adjunctive dexamethasone therapy.
• I can recognize and respond to acute complications of meningitis.
• I understand the importance of vaccination in preventing bacterial meningitis.
• I can identify which contacts require chemoprophylaxis after exposure to meningococcal or Hib meningitis.
• I can educate families about long-term follow-up needs and potential sequelae.