Ongoing HIV replication in cerebrospinal fluid under successful monotherapy.

Area of Science:

• Neurovirology
• Infectious Diseases
• Antiretroviral Therapy

Background:

• Antiretroviral therapy (ART) is crucial for managing HIV infection.
• Ritonavir/lopinavir (r/LPV) has been used as a protease inhibitor-based regimen.
• Monotherapy with ART regimens requires careful monitoring for efficacy and resistance.

Observation:

• A case of an HIV-infected patient on long-term r/LPV monotherapy presented with neurological symptoms.
• High HIV RNA levels were detected in the cerebrospinal fluid (CSF).
• HIV protease gene sequencing from CSF revealed resistance mutations to lopinavir and ritonavir.

Findings:

• HIV RNA levels in plasma and CSF were initially high despite r/LPV monotherapy.
• Drug resistance mutations in the HIV protease gene were identified in the CSF.
• Switching the antiretroviral regimen led to undetectable HIV RNA in both plasma and CSF within two months.

Implications:

• Ritonavir/lopinavir monotherapy may be insufficient for complete viral suppression in the central nervous system (CNS).
• HIV can compartmentalize within the CNS, leading to the selection of drug-resistant strains.
• This case highlights the importance of monitoring viral load and resistance in both plasma and CSF, especially in patients with neurological symptoms on ART.