Overview
Definition:
Meningococcal disease is a serious bacterial infection caused by the bacterium Neisseria meningitidis
It can manifest as meningitis (inflammation of the membranes surrounding the brain and spinal cord) or meningococcemia (septicemia), or both
It is a rapidly progressive and potentially fatal illness.
Epidemiology:
Meningococcal disease is a leading cause of bacterial meningitis and sepsis worldwide, particularly in adolescents and young adults
Outbreaks can occur, especially in crowded settings like schools, universities, and military barracks
The highest incidence is observed in infants, adolescents, and young adults
The disease is endemic globally, with seasonal peaks in winter and spring in temperate climates
Several serogroups (A, B, C, W, Y) are responsible for the majority of invasive diseases.
Clinical Significance:
Meningococcal disease is a medical emergency with high morbidity and mortality if not promptly recognized and treated
Survivors can experience long-term sequelae, including neurological deficits, hearing loss, and limb amputations
Effective prophylaxis and vaccination are crucial public health strategies to prevent disease and control outbreaks, making this topic vital for pediatricians preparing for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Sudden onset of fever
Severe headache
Stiff neck (nuchal rigidity)
Photophobia
Nausea and vomiting
Altered mental status (lethargy, irritability, confusion, coma)
Skin rash, often petechial or purpuric, appearing suddenly and spreading rapidly
Rapidly developing shock and circulatory collapse (in severe meningococcemia).
Signs:
Fever
Tachycardia
Hypotension
Nuchal rigidity on examination
Kernig's and Brudzinski's signs may be positive
Petechial or purpuric rash, which does not blanch under pressure
Signs of shock: cool extremities, poor peripheral perfusion, decreased urine output
Altered level of consciousness.
Diagnostic Criteria:
There are no strict diagnostic criteria for meningococcal disease in the absence of laboratory confirmation, but a combination of abrupt onset of fever, headache, nuchal rigidity, and a petechial or purpuric rash is highly suggestive
Definitive diagnosis relies on laboratory confirmation, typically through Gram stain and culture of cerebrospinal fluid (CSF) or blood
Nucleic acid amplification tests (NAATs) are also highly sensitive and specific for detecting N
meningitidis DNA.
Diagnostic Approach
History Taking:
Recent travel or exposure to crowded settings
Contact with a known case of meningococcal disease
History of vaccination
Onset and progression of symptoms
Presence of a rash
Any underlying immunocompromise or chronic medical conditions
Red flags: rapid deterioration, development of a non-blanching rash, shock.
Physical Examination:
Comprehensive assessment including vital signs (temperature, heart rate, blood pressure, respiratory rate)
Detailed neurological examination assessing mental status, meningeal signs (nuchal rigidity, Kernig's, Brudzinski's)
Thorough skin examination to characterize any rash (petechial, purpuric, maculopapular)
Assessment of hydration status and signs of shock.
Investigations:
Blood culture: essential for isolation of the organism and antibiotic sensitivity testing
Cerebrospinal fluid (CSF) analysis: Lumbar puncture performed if no contraindications exist
CSF should be analyzed for cell count, differential, protein, glucose, Gram stain, and culture
Rapid antigen detection tests and PCR for N
meningitidis can also be performed on CSF or blood
Complete blood count (CBC) with differential
Coagulation profile
Blood gas analysis and lactate levels to assess for shock and metabolic derangements
Imaging (CT/MRI brain) may be indicated if there are signs of increased intracranial pressure or focal neurological deficits.
Differential Diagnosis:
Other causes of bacterial meningitis: Streptococcus pneumoniae, Haemophilus influenzae type b (in unvaccinated individuals), Listeria monocytogenes
Viral meningitis
Rocky Mountain spotted fever
Typhus
Dengue hemorrhagic fever
Vasculitis
Idiopathic thrombocytopenic purpura (ITP) with purpura
Disseminated intravascular coagulation (DIC).
Management
Initial Management:
Immediate administration of empiric intravenous antibiotics as soon as possible, ideally after blood cultures are obtained but before lumbar puncture if there is a delay
Fluid resuscitation for shock
Supportive care to maintain airway, breathing, and circulation
Close monitoring of vital signs and neurological status.
Medical Management:
Empiric antibiotic therapy should cover N
meningitidis and other common bacterial meningitis pathogens
Recommended first-line agents for suspected meningococcal meningitis in children and adults include third-generation cephalosporins (e.g., ceftriaxone 100 mg/kg/day divided every 12-24 hours, maximum 4 g/day) or meropenem
Duration of treatment is typically 7-14 days, depending on the clinical presentation and response
Specific antibiotic choices should be guided by local resistance patterns and susceptibility testing
Corticosteroids (e.g., dexamethasone) may be considered for bacterial meningitis in certain age groups to reduce inflammation and neurological sequelae, but their role in meningococcal meningitis is debated and often reserved for cases with severe inflammation or complications.
Surgical Management:
Surgical intervention is generally not primary treatment for meningococcal disease
However, complications like subdural empyema, brain abscess, or hydrocephalus may require surgical drainage or other neurosurgical interventions
Amputations may be necessary for necrotic limbs resulting from severe meningococcemia.
Supportive Care:
Intensive care unit (ICU) admission for close monitoring of hemodynamics, respiratory status, and neurological function
Management of shock with intravenous fluids and vasopressors if necessary
Seizure management with anticonvulsants
Management of disseminated intravascular coagulation (DIC)
Nutritional support and fluid balance monitoring
Prevention of complications such as pressure sores and deep vein thrombosis
Rehabilitation and physiotherapy for survivors with neurological deficits or amputations.
Prophylaxis And Vaccination
Chemoprophylaxis:
Recommended for close contacts of a confirmed meningococcal case to prevent secondary transmission
Close contacts include household members, intimate partners, and individuals directly exposed to respiratory or oral secretions of the index case
Recommended regimens: Rifampin (adults: 600 mg PO bid x 2 days
children: 10 mg/kg PO bid x 2 days, max 600 mg/dose)
Ceftriaxone (adults: 250 mg IM x 1 dose
children <15 years: 125 mg IM x 1 dose)
Ciprofloxacin (adults: 500 mg PO x 1 dose
not recommended for children).
Vaccine Types:
Meningococcal conjugate vaccines (MenACWY-D, MenACWY-CRM, MenACWY-TT) protect against serogroups A, C, W, and Y
MenB vaccines (MenB-FHbp, MenB-4C) protect against serogroup B
The choice of vaccine depends on age, risk factors, and availability.
Routine Vaccination Schedule India:
In India, routine vaccination with meningococcal conjugate vaccines is not universally recommended but is available privately
Public health programs may recommend vaccination in specific outbreak situations or for high-risk groups
The Indian Academy of Pediatrics (IAP) recommends MenACWY vaccination for all children starting at 9 months of age with booster doses as per vaccine manufacturer guidelines
MenB vaccination is also recommended for high-risk individuals or during outbreaks of MenB disease
It is crucial to consult the latest IAP guidelines for specific age recommendations and catch-up schedules.
Catch Up And Risk Group Vaccination:
Catch-up vaccination with MenACWY is recommended for adolescents and young adults who have not received the vaccine
Vaccination is also recommended for individuals with specific risk factors, including complement deficiencies, asplenia, and those traveling to or residing in areas with a high prevalence of meningococcal disease (e.g., the meningitis belt in Africa)
Routine vaccination for serogroup B is recommended for adolescents and young adults and for individuals at increased risk of serogroup B disease.
Vaccine Efficacy And Duration:
Meningococcal conjugate vaccines (MenACWY) are highly effective in preventing disease caused by serogroups A, C, W, and Y
Serologic studies show that MenACWY vaccines induce protective antibody levels that persist for several years, though waning immunity may necessitate booster doses
MenB vaccines are also effective against serogroup B disease, though their effectiveness may vary by serotype and duration of protection
Effectiveness can be reduced in immunocompromised individuals.
Complications
Early Complications:
Septic shock
Disseminated intravascular coagulation (DIC)
Acute respiratory distress syndrome (ARDS)
Myocarditis
Pericarditis
Arthritis
Renal failure
Cerebral edema
Seizures
Hydrocephalus.
Late Complications:
Neurological sequelae: learning disabilities, developmental delay, cognitive impairment, motor deficits, epilepsy
Hearing loss (sensorineural)
Visual impairment
Limb amputations due to purpura fulminans or peripheral necrosis
Skin scarring and cosmetic disfigurement.
Prevention Strategies:
Prompt diagnosis and treatment of invasive meningococcal disease
Effective antimicrobial therapy
Administration of chemoprophylaxis to close contacts
Widespread implementation of meningococcal vaccination programs targeting key age groups and high-risk populations
Public health surveillance to detect and respond to outbreaks.
Key Points
Exam Focus:
Bacterial etiology: Neisseria meningitidis
Main clinical syndromes: meningitis and meningococcemia
Rapid progression and high mortality
Importance of early diagnosis and empiric antibiotics
Role of lumbar puncture and blood cultures
Chemoprophylaxis for contacts: rifampin, ceftriaxone, ciprofloxacin
Meningococcal vaccines: MenACWY and MenB
Vaccination schedule and catch-up recommendations
Differential diagnosis of meningitis and purpuric rash.
Clinical Pearls:
Always consider meningococcal disease in a child or adolescent with fever and rash, especially if the rash is petechial or purpuric
The absence of a rash does not rule out meningococcemia
Prompt administration of antibiotics is critical, even before definitive diagnosis if there is clinical suspicion
Educate parents about the importance of meningococcal vaccination and seek prompt medical attention for any signs of illness.
Common Mistakes:
Delaying antibiotic administration due to a focus on definitive diagnosis before lumbar puncture
Incorrect identification of close contacts for chemoprophylaxis
Misinterpreting the rash as non-infectious
Not considering meningococcal disease in immunocompromised individuals or those with atypical presentations
Inadequate understanding of current meningococcal vaccine recommendations and schedules.