Can Cytomegalovirus (CMV) infection in individuals with Human Immunodeficiency Virus (HIV) cause cranial nerve deficits?

CMV Infection in HIV Can Cause Cranial Nerve Deficits

Yes, Cytomegalovirus (CMV) infection in HIV-infected individuals can definitely cause cranial nerve deficits, particularly in patients with advanced immunosuppression and CD4+ counts below 50 cells/μL. 1, 2, 3

Neurological Manifestations of CMV in HIV

CMV can affect the central nervous system in HIV-infected individuals in several ways:

CMV Ventriculoencephalitis

• Presents with an acute course and focal neurologic signs
• Frequently involves cranial nerve palsies - a hallmark clinical feature 1, 3
• Often accompanied by nystagmus (particularly gaze-directed) 3
• Rapid progression to death if untreated
• Periventricular enhancement on CT/MRI is characteristic 1, 2
• CSF typically shows pleocytosis with elevated protein and hypoglycorrhachia 3

CMV Polyradiculomyelopathy

• Presents as a Guillain-Barré-like syndrome
• Characterized by urinary retention and progressive bilateral leg weakness
• Can progress to loss of bowel and bladder control and flaccid paraplegia
• CSF shows neutrophilic pleocytosis with hypoglycorrhachia and elevated protein 1, 2
• May involve cranial nerves in some cases 4

Specific Cranial Nerve Involvement

• Multiple cranial nerves can be affected, including:
  • Auditory nerve (VIII) involvement causing hearing loss 5
  • Other cranial nerves reported to be affected include radial, ulnar, and peroneal nerves 4
  • Optic nerve involvement in cases where CMV retinitis extends to affect the optic nerve 1

Risk Factors and Clinical Context

The risk of CMV neurological disease is highest in:

• HIV patients with CD4+ counts <50 cells/μL 1, 2
• Patients with prior opportunistic infections 1
• Patients with high HIV viral loads (>100,000 copies/mL) 1
• Patients with CMV retinitis (often precedes neurological manifestations) 3

Diagnostic Approach

When cranial nerve deficits are observed in HIV patients:

1. Consider CMV as a potential cause, especially with CD4+ <50 cells/μL
2. Look for evidence of CMV infection elsewhere (particularly retinitis)
3. Perform CSF analysis - look for:
   • Pleocytosis (lymphocytic or mixed with neutrophils)
   • Low-to-normal glucose levels
   • Elevated protein levels 1, 2
4. Neuroimaging (CT/MRI) to detect periventricular enhancement suggestive of CMV ventriculoencephalitis 1, 2
5. PCR for CMV DNA in CSF is valuable for diagnosis 4

Clinical Course and Prognosis

Without treatment, CMV neurological disease involving cranial nerves has a poor prognosis:

• CMV ventriculoencephalitis typically leads to death within approximately 4 weeks of symptom onset 3
• Intracranial hypertension symptoms at admission are associated with poor outcomes 6
• Response to antiviral therapy for CMV encephalitis is often limited 4, 3

Pitfalls and Caveats

1. CMV retinitis often precedes or accompanies neurological manifestations - always perform ophthalmologic examination 3
2. CMV neurological disease can develop despite maintenance therapy with ganciclovir or foscarnet 3
3. CMV ventriculoencephalitis can be confused with HIV-associated dementia - periventricular enhancement on imaging helps distinguish them 1
4. Improvement with treatment may take months in some cases 7
5. With the advent of HAART (now called ART), the incidence of CMV disease has decreased, but remains a concern in patients with advanced immunosuppression 4

In summary, cranial nerve deficits are a well-documented manifestation of CMV infection in HIV-infected individuals, particularly in the context of CMV ventriculoencephalitis, and should prompt immediate evaluation and treatment in patients with advanced immunosuppression.