Meningitis: Symptoms, Types, Causes and Treatment

Meningitis is a potentially life-threatening condition that involves inflammation of the protective membranes (meninges) covering the brain and spinal cord. While advances in medicine have reduced its prevalence and improved outcomes, meningitis remains a significant global health concern due to its rapid onset, potential for severe complications, and diverse causes. Understanding the symptoms, types, causes, and treatment of meningitis is crucial for early recognition, effective management, and prevention of serious outcomes.

Symptoms of Meningitis

Recognizing the symptoms of meningitis is essential for timely diagnosis and intervention. Symptoms can vary based on the type of meningitis, the age of the patient, and other factors, but certain classic signs are strongly associated with the condition. While some symptoms are highly suggestive, others may be subtle, especially in very young children, the elderly, or immunocompromised individuals.

Symptom	Description	Typical Onset	Source(s)
Headache	Persistent, intense pain	Rapid/subacute	1 2 3 4
Fever	Elevated body temperature	Rapid/subacute	1 2 3 4
Neck Stiffness	Resistance to neck flexion	Rapid/subacute	1 3 4 5
Altered Mental State	Confusion, lethargy, irritability	Rapid/subacute	2 3 4
Nausea/Vomiting	Often accompanies headache	Rapid/subacute	2 4
Photophobia	Sensitivity to light	Variable	4
Seizures	Involuntary muscle contractions	Variable	4
Skin Rash	Petechial or purpuric, especially with meningococcal infection	Rapid	1 4

Table 1: Key Symptoms

Classic Symptom Triad and Beyond

The "classic triad" of meningitis—fever, neck stiffness (nuchal rigidity), and altered mental status—has long been used as a clinical hallmark. However, not all patients present with all three. Up to 95% of cases will have at least two of these four: headache, fever, neck stiffness, and altered mental state 3 4. Headache is reported in the vast majority of cases, sometimes with associated nausea and vomiting 2.

Additional and Age-Dependent Signs

• Photophobia (light sensitivity) and seizures may accompany classic symptoms, particularly in severe or advanced cases 4.
• Skin rash, notably petechiae (small, red or purple spots), is a critical clue in meningococcal meningitis and may signal a rapidly progressing, potentially fatal course 1.
• Nuchal rigidity (neck stiffness) is a key sign but less sensitive in very young children and the elderly 4 5.
• Non-specific symptoms such as irritability, poor feeding in infants, or lethargy may be the only clues in vulnerable populations 4.

Diagnostic Physical Signs

• Kernig’s and Brudzinski’s signs are classic but not always present or reliable, especially in children or older adults 4 5.
• Intracranial pressure signs—vomiting, decreased consciousness, or focal neurological findings—may develop if the infection causes swelling or obstruction 4.

Variability in Presentation

Symptoms can develop acutely (within hours to a few days), or more insidiously in subacute and chronic forms. This variability underscores the importance of clinical vigilance and comprehensive assessment 2 4.

Types of Meningitis

Meningitis is not a single disease but a syndrome with multiple underlying causes. Understanding the different types is crucial for targeted treatment and prevention strategies.

Type	Main Features	Usual Duration	Source(s)
Acute Meningitis	Sudden onset, severe symptoms	≤ 5 days	2 3 4
Subacute Meningitis	Gradual onset, milder progression	≥ 5 days	2 4
Chronic Meningitis	Slow progression, persistent symptoms	≥ 4 weeks	2 4
Bacterial Meningitis	Often severe, high mortality risk	Variable	3 6 7 8
Viral (Aseptic) Meningitis	Usually milder, self-limiting	Variable	4 6
Fungal/Parasitic Meningitis	Rare, often in immunocompromised	Variable	6
Non-infectious Meningitis	Due to autoimmune, neoplastic, or drug-induced causes	Variable	2 6

Table 2: Types of Meningitis

Acute, Subacute, and Chronic Meningitis

• Acute meningitis presents rapidly, often within hours to a few days. It is most commonly caused by bacteria or viruses and is a medical emergency 2 3 4.
• Subacute and chronic meningitis have a more gradual onset, sometimes over weeks. These forms are more likely to be caused by indolent bacteria (such as Mycobacterium tuberculosis or Brucella), fungi, or non-infectious processes like autoimmune disease or malignancy 2.

Infectious vs. Non-infectious Meningitis

• Bacterial meningitis is the most severe and carries the highest risk of complications and death, especially in the very young, elderly, and immunocompromised 3 6 7. The most common pathogens vary by age and geography but include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae 7 8.
• Viral (aseptic) meningitis is more common and tends to be less severe, often resolving without specific treatment 4 6.
• Fungal and parasitic meningitis are rare, usually affecting those with compromised immune systems 6.
• Non-infectious meningitis results from autoimmune disorders, cancers, or reactions to certain medications 2 6.

Special Considerations

• Meningoencephalitis refers to simultaneous inflammation of the meninges and brain parenchyma, resulting in additional neurological symptoms 4.
• Nosocomial (hospital-acquired) meningitis can complicate neurosurgical procedures and often involves drug-resistant organisms 9.

Causes of Meningitis

The causes of meningitis are diverse and can be grouped into infectious and non-infectious categories. The most common causes depend on patient age, immune status, and geographic location.

Cause Type	Examples/Pathogens	Risk Groups	Source(s)
Bacterial	S. pneumoniae, N. meningitidis, H. influenzae, E. coli, Group B Streptococcus, L. monocytogenes, Brucella	Children, adults, elderly, neonates	1 3 6 7 9
Viral	Enteroviruses, HSV, VZV, Mumps	All ages	4 6
Fungal	Cryptococcus, Candida	Immunocompromised	6
Parasitic	Naegleria fowleri, Toxoplasma	Rare cases	6
Non-infectious	Autoimmune, neoplastic, drug-induced	Variable	2 6

Table 3: Major Causes of Meningitis

Bacterial Causes

Bacterial infections are the most dangerous causes of meningitis. The predominant bacteria include:

• Streptococcus pneumoniae: The leading cause in all age groups, accounting for 25–41% of bacterial meningitis globally 7 8.
• Neisseria meningitidis: Common in children and young adults; associated with outbreaks and rapid progression 1 7 8.
• Haemophilus influenzae: Once a major cause in children, now much less common due to vaccines 7 8.
• Gram-negative bacilli (E. coli, especially in neonates; Pseudomonas, Acinetobacter in post-surgical cases): Cause both community-acquired and hospital-acquired infections 9.

Other bacteria such as Listeria monocytogenes (in the elderly, pregnant women, immunocompromised), Brucella (in endemic areas), and Mycobacterium tuberculosis (chronic cases) are important in certain populations 2 7.

Viral Causes

Viruses are the most frequent cause of aseptic (non-bacterial) meningitis:

• Enteroviruses are the most common.
• Herpesviruses (HSV, VZV), mumps, and others can also cause viral meningitis 4 6.

These cases are usually milder and self-limiting, but can be severe in newborns or the immunocompromised 6.

Fungal and Parasitic Causes

• Fungal meningitis (Cryptococcus, Candida) is rare but serious, typically in immunocompromised patients.
• Parasitic meningitis is extremely rare, often associated with exposure to contaminated water or immunodeficiency 6.

Non-infectious Causes

• Autoimmune diseases (e.g., lupus, sarcoidosis)
• Neoplastic processes (infiltration by cancer cells)
• Drug-induced reactions (certain medications can cause aseptic meningitis) 2 6

These forms often present subacutely or chronically and may require advanced diagnostics for identification.

Treatment of Meningitis

Prompt and appropriate treatment is essential to improve outcomes and reduce complications in meningitis. The approach varies depending on the underlying cause, patient age, and local patterns of antibiotic resistance.

Treatment Modality	Description	Indication	Source(s)
Empiric Antibiotics	Start immediately; cover likely bacteria	Acute bacterial	1 3 8 14 16
Targeted Antibiotics	Adjust based on cultures/sensitivities	Proven bacterial	1 16
Antivirals	Acyclovir for HSV, etc.	Suspected viral	4 6
Antifungals	Amphotericin B, etc.	Fungal cases	6
Corticosteroids (e.g., dexamethasone)	Reduce inflammation, neurologic sequelae	Certain bacterial	3 8 12 15 16
Supportive Care	Fluids, seizure control, ICP management	All types	3 4 8
Vaccination	Prevention (pneumococcal, meningococcal, Hib)	At-risk groups	1 7 8

Table 4: Treatment Strategies

Immediate and Empiric Therapy

• Empiric antibiotics must be started as soon as bacterial meningitis is suspected, even before confirming the diagnosis, because delays can be fatal 1 3 8 14.
  • Typical empiric regimens: third-generation cephalosporin (e.g., ceftriaxone or cefotaxime) plus vancomycin; add ampicillin for Listeria coverage in neonates, elderly, or immunocompromised 16.
  • For meningococcal disease, cefotaxime or ceftriaxone are recommended 1.
• Antivirals such as acyclovir are used if herpes simplex virus meningitis is suspected 4 6.
• Antifungals are reserved for proven fungal cases, often in the immunocompromised 6.

Adjunctive Therapies

• Corticosteroids (e.g., dexamethasone) can reduce inflammation and the risk of neurologic complications (like hearing loss), especially in high-income settings and in specific bacterial infections (e.g., S. pneumoniae) 3 8 12 15 16.
• The use of steroids is debated in low-resource settings and may not benefit all groups 15.

Supportive and Symptomatic Care

• Management of seizures, control of intracranial pressure, and fluid/electrolyte balance are vital 3 4 8.
• Intensive care may be needed for patients with severe disease or complications (e.g., shock, respiratory failure) 1 3 4.

Prevention

• Vaccination has dramatically reduced the incidence of meningitis caused by H. influenzae, N. meningitidis, and S. pneumoniae 1 7 8.
• Prophylactic antibiotics may be given to close contacts of patients with meningococcal meningitis 1 8.

Evolving Challenges

• Antibiotic resistance: Increasing resistance among meningeal pathogens is altering first-line therapy and necessitating ongoing surveillance 8 15 16.
• Emerging therapies: New antibiotics and adjunctive treatments (e.g., glycerol, paracetamol, hypothermia) are under investigation, particularly for resistant or severe cases 15.

Conclusion

Meningitis is a complex, potentially devastating condition that requires rapid recognition and action. Understanding its symptoms, types, causes, and treatment options is essential for healthcare providers, patients, and caregivers alike. Early intervention, advances in vaccines, and ongoing research continue to improve outcomes, but vigilance is necessary, especially as antibiotic resistance emerges and new pathogens appear.

Key Points Recap:

• Symptoms: Headache, fever, neck stiffness, altered mental status, and sometimes rash or seizures are key signs; presentation can vary by age and cause [1–5].
• Types: Includes acute, subacute, and chronic forms, with bacterial, viral, fungal, and non-infectious etiologies [2–4,6].
• Causes: Most commonly bacteria (especially S. pneumoniae, N. meningitidis), but also viruses, fungi, parasites, and non-infectious factors 1 3 6 7 9.
• Treatment: Early empiric antibiotics for suspected bacterial cases, adjunctive steroids in select groups, supportive care, and prevention through vaccination are key [1,3,8,12,14–16].

Meningitis remains a medical emergency—swift diagnosis and treatment save lives. Public health efforts, vaccine programs, and ongoing research are vital to further reduce its impact worldwide.