From the Guidelines
Herpes simplex virus (HSV) is a common cause of increased cerebrospinal fluid (CSF) pressure, particularly in adults, as it can lead to viral encephalitis and subsequent inflammation of the meninges or brain tissue, resulting in elevated intracranial pressure 1.
Causes of Increased CSF Pressure
Several viruses can increase CSF pressure, including:
- Herpes simplex virus (HSV)
- Varicella-zoster virus (VZV)
- Enteroviruses
- HIV
- West Nile virus
- Mumps virus These viruses cause viral meningitis or encephalitis, leading to inflammation of the meninges or brain tissue, which triggers increased production of CSF, decreased CSF absorption, or obstruction of CSF flow, resulting in elevated intracranial pressure.
Diagnosis and Treatment
Diagnosis typically involves a lumbar puncture (LP) to confirm the diagnosis and rule out other causes, as well as imaging studies such as CT or MRI scans to evaluate for hydrocephalus or other complications 1. Treatment involves antiviral medications specific to the causative virus, such as acyclovir for HSV (10-15 mg/kg IV every 8 hours for 14-21 days) and VZV infections, as well as supportive care including pain management with acetaminophen or NSAIDs, adequate hydration, and sometimes corticosteroids to reduce inflammation 1. In severe cases with dangerously high CSF pressure, therapeutic lumbar punctures may be performed to drain excess fluid and relieve pressure, and early diagnosis and treatment are crucial to prevent complications like seizures, cognitive impairment, or death 1.
Key Considerations
It is essential to note that increased intracranial pressure can occur early in the course of disease, and pressures of 180–250 mm H2O are concerning, but do not require specific intervention, while pressures ≥250 mm H2O define the need for urgent or emergent intervention 1. Additionally, the management of elevated intracranial pressure is critical, and aggressive management has been shown to improve outcomes in patients with cryptococcal meningitis, a condition that can also increase CSF pressure 1.
From the Research
Viruses that can Increase CSF Pressure
- Herpes simplex virus (HSV) can cause an increase in cerebrospinal fluid (CSF) pressure, as it can lead to inflammation and damage to the blood-brain barrier 2, 3.
- Cytomegalovirus (CMV) meningoencephalitis can also cause elevated CSF pressure, characterized by fever, altered mental status, or meningismus with pleocytosis, elevated protein, and hypoglycorrhachia on CSF analysis 4.
- Varicella-zoster virus (VZV) can cause viral meningitis, which may lead to increased CSF pressure, although the evidence is limited 5.
- Other viral infections, such as enterovirus and West Nile virus, can also cause meningoencephalitis and potentially increase CSF pressure, but the clinical presentations and CSF findings may differ from those of CMV and HSV 4.
CSF Findings in Viral Infections
- Lymphoid pleocytosis is a common finding in CSF of patients with viral infections, including HSV and CMV 2, 4, 3.
- Increased protein levels and IgG content in CSF are also common in viral infections, particularly in HSV encephalitis 2, 3.
- The use of polymerase chain reaction (PCR) and other molecular techniques can aid in the diagnosis of viral infections, including HSV, CMV, and VZV 5, 6.