Why Aseptic Meningitis Is Often Less Worrisome Than Bacterial—and How Doctors Typically Treat It

It’s important, though, to rule out bacterial causes before determining a course of treatment.

Aseptic meningitis, a condition that exhibits symptoms similar to bacterial meningitis, such as severe headaches, fever, nausea, vomiting, light sensitivity, and neck stiffness, is generally less severe but still a cause for concern. According to a 2017 review in American Family Physician, it is the most common form of meningitis, affecting approximately eight out of every 100,000 adults annually. In this comprehensive exploration of aseptic meningitis, we will delve into its types, symptoms, causes, diagnosis, and treatment, shedding light on this complex medical issue.

Understanding Aseptic Meningitis

Aseptic meningitis, sometimes referred to as non-bacterial or viral meningitis, is characterized by symptoms that closely resemble bacterial meningitis. It occurs when there is inflammation or swelling in a part of the body known as the “meninges,” a set of membranes that cushion and protect the brain and spinal cord.

While bacterial meningitis is caused by specific bacteria, aseptic meningitis occurs when inflammation of the meninges is triggered by various factors other than bacteria, leading to a broad category of non-infectious agents.

Types and Causes of Aseptic Meningitis

Viral Aseptic Meningitis

The most common type of aseptic meningitis is viral aseptic meningitis. According to the CDC, the majority of viral meningitis cases in the United States are attributed to non-polio enteroviruses, which are also responsible for causing seasonal colds, especially in children and teenagers. However, a wide range of other viruses can also cause aseptic meningitis. These include:

• Varicella zoster (responsible for chickenpox and shingles)
• Influenza virus
• Measles virus
• Mumps virus
• HIV
• Herpes simplex viruses
• West Nile virus and other arboviruses
• Lymphocytic choriomeningitis virus

While symptoms of viral aseptic meningitis can be severe, it is generally not a life-threatening disease, especially among younger adults, teenagers, and children. Common symptoms in this age group include headaches, fever, nausea, and vomiting. The prognosis for viral aseptic meningitis is typically favorable, with most individuals recovering without complications.

Other Causes of Aseptic Meningitis

Beyond viral causes, aseptic meningitis can be triggered by a diverse array of factors, including:

• Fungi: Fungal meningitis can occur when a fungal infection spreads to the brain or spinal cord from another part of the body. This type of aseptic meningitis is more likely to affect individuals with weakened immune systems, such as those with HIV. Common fungi associated with fungal meningitis include Histoplasma and Blastomyces.
  
• Medications: Some medications, including over-the-counter pain relievers, antibiotics, immunosuppressive drugs, and antiepileptic drugs, can induce aseptic meningitis. Notably, ibuprofen, a nonsteroidal anti-inflammatory drug (NSAID), is a frequent cause.
  
• Underlying Diseases: Certain diseases, such as cancer, tuberculosis, syphilis, and tick-borne illnesses, can lead to aseptic meningitis. The risk of developing aseptic meningitis is influenced by factors such as age, overall health, immunization status, and specific exposures.
  
• Infections Near the Brain or Spinal Cord: Infections in close proximity to the brain or spinal cord can trigger aseptic meningitis. This includes tick- or mosquito-borne infections, emphasizing the importance of inquiring about recent travels or outdoor activities during medical assessments.
  
• Vaccines: Some vaccines, including rubella, varicella, rabies, pertussis, and influenza vaccines, have been associated with aseptic meningitis. However, such cases are exceedingly rare, and the benefits of vaccination far outweigh the risks.
  
• Parasitic Infections: Although uncommon, certain parasites can cause aseptic meningitis. Individuals may become infected through the consumption of contaminated food or contact with animals carrying these parasites.
  
• Other Diseases: Rarely, conditions like tuberculosis and certain parasites can lead to aseptic meningitis. A comprehensive medical history and diagnostic evaluation are essential in determining the precise cause.

Diagnosing Aseptic Meningitis

Diagnosing aseptic meningitis involves a thorough evaluation of the patient’s medical history, clinical presentation, and diagnostic tests. Lumbar puncture, commonly known as a spinal tap, is a pivotal diagnostic procedure in which a small amount of cerebrospinal fluid is withdrawn from the lower back and analyzed.

Cerebrospinal fluid analysis plays a crucial role in distinguishing between bacterial and viral (aseptic) meningitis, as well as identifying the specific causative agent. White blood cell and glucose levels, cultures, and other diagnostic tests can provide valuable insights into the diagnosis.

Additional tests, such as CT scans or MRIs of the head to assess swelling or inflammation and blood cultures to detect bacteria, may also be employed in the diagnostic process.

Aseptic Meningitis Treatment

The treatment approach for aseptic meningitis depends on its underlying cause. When bacterial meningitis is suspected, healthcare providers often initiate prophylactic antibiotic therapy until definitive diagnostic results confirm or rule out bacterial involvement.

Lumbar puncture, as previously mentioned, is instrumental in diagnosing the condition accurately. Analyzing cerebrospinal fluid assists in distinguishing between bacterial and viral (aseptic) meningitis, guiding the treatment strategy.

• Bacterial Meningitis: Immediate treatment with intravenous antibiotics targeting the specific bacterial pathogen is essential. Corticosteroids may also be prescribed to reduce the risk of severe complications.
  
• Viral Aseptic Meningitis: Most cases do not require specific treatment, with symptomatic relief, rest, and supportive care being the primary measures. In many instances, individuals recover within ten days or less without intervention. However, meningitis caused by certain viruses, such as the West Nile virus, can be more severe and may result in lingering fatigue and weakness.
  
• Fungal Aseptic Meningitis: Fungal meningitis necessitates prolonged treatment with high-dose antifungal medications, the duration of which depends on factors such as the patient’s immune status and the specific fungus involved.
  
• Medication-Induced Aseptic Meningitis: In cases where medications are the causative agents, the primary treatment is discontinuing the implicated drug. Generally, this leads to symptom resolution within 24 to 48 hours. Supportive care can be provided to ensure patient comfort during recovery.

In summary, aseptic meningitis, while mirroring the symptoms of bacterial meningitis, is typically less severe and can result from various causes, including viruses, fungi, medications, underlying diseases, infections, vaccines, and parasites. Diagnosis involves a comprehensive evaluation, including cerebrospinal fluid analysis and other diagnostic tests, to identify the specific causative agent. Treatment strategies vary based on the underlying cause, emphasizing the importance of accurate diagnosis and prompt medical intervention. While most cases of aseptic meningitis have a favorable prognosis, healthcare providers remain vigilant to ensure patient well-being and recovery.