Viral Meningitis Treatment & Management

Treatment for viral meningitis is mostly supportive. Rest, hydration, antipyretics, and pain or anti-inflammatory medications may be given as needed. The most important decision is whether to initiate antimicrobial therapy empirically for bacterial meningitis while waiting for the cause to be identified. Intravenous (IV) antibiotics should be administered promptly if bacterial meningitis is suspected. ^[14]

No surgical therapy is usually indicated in patients with viral meningitis. In rare patients in whom viral meningitis is complicated by hydrocephalus, a CSF diversion procedure, such as ventriculoperitoneal (VP) or LP shunting, may be required. Ventriculostomy with an external collection system is indicated in the rare cases of acute hydrocephalus.

Patients with signs and symptoms of meningoencephalitis should receive acyclovir early to possibly curtail HSV encephalitis. Therapy can be modified as the results of Gram stain, cultures, and PCR testing become available. Patients in unstable condition need critical care unit admission for airway protection, neurologic checks, and the prevention of secondary complications.

Enteroviruses and HSV are each capable of causing viral septic shock in newborns and infants. In these young patients, broad-spectrum antibacterial coverage and acyclovir should be instituted as soon as the diagnosis is suspected. Special attention should be paid to fluid and electrolyte balance (especially sodium), since SIADH has been reported. Fluid restriction, diuretics, and, rarely, hypertonic saline infusion may be used to correct the hyponatremia. Prevention of secondary infections of urinary tract and pulmonary systems is of paramount importance.

Waiting for LP results should not delay administration of antibiotics when warranted on clinical grounds. Broad-spectrum coverage is attained with ampicillin and a third-generation cephalosporin (ceftriaxone or cefotaxime; ceftazidime can also be used). Aminoglycosides are used in severe infections in neonates or children. Antituberculous, antifungal, and antiretroviral medications are reserved for clinically suggested or laboratory-confirmed cases.

Seizures should be treated immediately with IV anticonvulsants, such as lorazepam, phenytoin, midazolam, or a barbiturate. Unconscious patients with viral encephalitis may be in nonconvulsive status epilepticus, and EEG is used to reveal and monitor subclinical seizures.

Cerebral edema does occur in cases of severe encephalitis and may require intracranial pressure control by infusion of mannitol (1 g/kg initial dose followed by 0.25-0.5 g/kg q6h), IV dexamethasone, or intubation and mild hyperventilation, with arterial PCO₂ around 28-30 mm Hg. Placement of an intracranial pressure monitor with transduced intraparenchymal pressure is recommended in these cases.

Multiple antiviral medications are currently being tested in the general population; their impact on preventing the potential, rare sequelae of viral meningitis has not yet been established. In herpetic viral infections, acyclovir is significantly beneficial only if given very early in the course of the infection. Suspected cases should be treated as soon as possible; in cases complicated by seizures, encephalitis is assumed and acyclovir should be initiated.

Anti-HIV therapy is initiated when the patient’s history or associated risk factors suggest the early phases of HIV meningoencephalitis.

Ganciclovir for CMV-related infections is reserved for severe cases with positive CMV culture or when a congenital infection or an AIDS-related infection is strongly suspected.

Administration of IVIg to neonates with overwhelming enteroviral meningitis has met with occasional success and is reserved for severe cases lacking other therapeutic options.

A patient’s activity limitations should be individualized based on each patient's clinical picture. Bed rest is recommended for the acute phase of infection.

Patients with focal signs, severe lethargy, or headache should be transferred to the closest institution with CT-scanning capability. Children younger than age 1 year and neonates should be transferred to a hospital equipped with pediatric intensive care capability.

Medications should be instituted prior to transfer in select cases, particularly agents being used in empiric therapy for bacterial meningitis, if indicated.

Although most patients with signs of meningitis are hospitalized, a subgroup with aseptic meningitis is treated appropriately in an ambulatory setting. Absolute criteria for discharge of these patients from the emergency department (ED) have not been established, but investigations in children suggest that age greater than 1 year, nontoxic clinical appearance, normal serum WBC count, mild CSF pleocytosis, negative CSF Gram stain, adequate control of symptoms, and a reliable family setting may serve as some useful factors in the decision to discharge.

Prospective studies would aid in further delineating guidelines for patient discharge and follow-up. Most admissions are for IV hydration, empiric antibiotics, and observation, or they occur if a diagnosis other than viral meningitis is being considered.

Arrange follow-up with the primary care physician in 1-3 days, with explicit instructions to return to the ED in case of any clinical worsening. A follow-up call in a day to report on the status of the patient seems like a common-sense recommendation.

In select patients, additional serum specimens 10-21 days later may reveal a specific viral antibody titer rise, which is useful in arboviral, LCMV, and some nonviral causes of aseptic meningitis.

In cases complicated by seizures, outpatient anticonvulsants should be continued and close follow-up should be considered in the first week after discharge.

Outpatient supplies of antipyretics, such as acetaminophen, and antiemetics, such as promethazine, may be given to ambulatory patients who do not appear clinically toxic. No strict criteria exist for discharging patients with viral meningitis.

Consultations may be sought from clinicians in the following fields:

• Neurology - Seizure control, EEG, management of brain edema in refractory cases, neurointensive care

• Neurosurgery - Placement of intracranial pressure monitor, CSF shunting or temporary drainage in patients with hydrocephalus, neurointensive care

• Infectious disease - Control of epidemics, isolation of patient and contacts, choice of antibiotics in refractory or atypical cases

• Neonatology - Any newborn or infant with severe viral meningitis requiring intensive care