Aseptic meningitis is an inflammatory condition affecting the protective membranes covering the brain and spinal cord, known as the meninges, without involvement of typical bacterial pathogens.

Its name stems from the negative results observed in routine bacterial cultures of cerebrospinal fluid (CSF), differentiating it from bacterial meningitis.

Causes and Pathophysiology

The majority of aseptic meningitis cases are attributed to viral pathogens, especially enteroviruses such as Coxsackievirus and Echovirus. Other viral sources include mumps and arboviruses. Beyond infectious causes, certain medications—including nonsteroidal anti-inflammatory drugs and antibiotics can induce aseptic meningitis through hypersensitivity or inflammatory reactions. Autoimmune conditions like systemic lupus erythematosus may also incite meningeal inflammation without infectious etiology.

The disease mechanism involves inflammation of meninges due to immune response activation, leading to increased permeability, cellular infiltration, and release of inflammatory mediators. This disrupts normal CSF composition and meningeal function, resulting in neurological symptoms.

Common Symptoms and Clinical Presentation

Symptoms of aseptic meningitis vary across age groups, but some are widely recognized. Fever is commonly present, often accompanied by headache that ranges from mild discomfort to severe, debilitating pain. Nuchal rigidity, or stiff neck, results from meningeal irritation and is a hallmark of meningitis presentations. Other features include photophobia (sensitivity to light), malaise, nausea, and vomiting. In infants and young children, irritability, poor feeding, bulging fontanelle, and respiratory issues may develop.

Diagnostic Evaluation

Definitive diagnosis relies on lumbar puncture to obtain CSF for analysis. Characteristic findings in aseptic meningitis usually include elevated white blood cell counts with lymphocytic predominance, normal to mildly elevated protein, and normal glucose levels. Confirming viral etiology may involve polymerase chain reaction (PCR) tests or specific serologic assays.

Additional diagnostics such as blood cultures, imaging (CT or MRI), and neurological assessments are performed to exclude bacterial infection, intracranial complications, or alternative diagnoses. Differential diagnosis is broad, encompassing bacterial meningitis, encephalitis, subarachnoid hemorrhage, and systemic infections with neurological symptoms.

Therapeutic Approaches and Management

Treatment for aseptic meningitis depends largely on the underlying cause. Viral meningitis, which constitutes the bulk of cases, often resolves without antivirals; supportive care including hydration, analgesia, and rest constitute the mainstay of management. Severe cases associated with simplex virus benefit from antiviral therapy such as acyclovir.

Prognosis and Potential Complications

Most individuals recover fully from aseptic meningitis without residual deficits. Nonetheless, some may experience prolonged fatigue, headaches, or cognitive changes post-infection. Rare complications include seizures or cranial nerve palsies. Prompt diagnosis and management reduce the risk of these outcomes, underscoring the importance of vigilance in clinical assessment.

Dr. Auwaerter, Clinical Director of the Division of Infectious Diseases at Johns Hopkins Medicine, emphasizes that: “Aseptic meningitis symptoms include fever, headache, and a stiff neck. Most children and adolescents recover without complications.”

Aseptic meningitis, primarily a viral-mediated inflammation of meninges, presents with fever, headache, stiff neck, and other systemic symptoms. Distinguishing it from bacterial meningitis through clinical evaluation and CSF analysis guides appropriate treatment strategies.

Supportive care remains the cornerstone for viral cases, while specific therapies are reserved for particular etiologies. Awareness of diverse causes, symptom variations, and management options enables optimized patient care and mitigates potential complications, ensuring recovery and restoration of neurological health.