Human Immunodeficiency Virus (HIV) can often cause neurologic complications, 40% of patients with HIV present with neurologic symptoms and neuropathologic abnormalities are detected in 80% of patients after death. While HIV can be kept under control by various drugs, a new report published in Clinical Infectious Diseases has confirmed that patients may harbor HIV in their brain even when the disease is otherwise being managed. Scientists have now created a method that uses Magnetic Resonance Imaging, MRI scans, to find HIV that is persisting in the brain. The video below illustrates what it's like to get an MRI.
"Before we had effective treatments for HIV, AIDS often led to dementia and other problems in the brain," explained senior author of the Wellcome-funded work, Professor Ravi Gupta at University College London (UCL) Infection & Immunity, who is also an Honorary Consultant in Infectious Diseases at The Hospital for Tropical Diseases, UCLH NHS Foundation Trust. "Thankfully this is less common now that we can treat HIV, but up to half of HIV patients still report cognitive problems. We see evidence that HIV has spread to the brain in around ten to fifteen percent of these patients, but in most cases the symptoms are down to other causes. At the moment we have to perform a lumbar puncture to confirm this, which involves inserting a needle into the back to draw out the spinal fluid and test it for HIV. This is quite an invasive procedure that requires patients to stay in hospital for several hours. Our new study shows that MRI scans could help to identify high-risk individuals for further follow-up tests," he explained.
For this research, the investigators analyzed data from 146 HIV patients that had been checked for cognitive dysfunction between 2011 and 2015. It was revealed that HIV infections were active in the brains of 22 patients (15% of the cohort). They also found that if definitive signs of change in the white matter of the brain were observed in a patient, then that patient was ten times more likely to harbor HIV in their brain when compared to brains whose white matter looked normal. Those brain alterations are called diffuse white matter signal abnormalities, and they have been correlated with cognitive problems and can be caused by brain inflammation resulting from an HIV infection.
"HIV treatments have come a long way, but patients whose HIV is suppressed by drugs can still have cognitive problems due to HIV related inflammation," explained Gupta. "MRI scans can help to diagnose these patients, whether showing an elevated risk of HIV-related problems or finding a different cause that can then be treated. Where HIV has spread to the brain, we can change the treatment regime to add drugs that cross the blood-brain barrier more effectively to control the infection."
For more on the neurologic complications of HIV, check out the video above from the Cleveland Clinic.