I just got the results from an MRI of the brain with contrast, and I don't understand them. The MRI was performed because of concentration & memory problems and excessive sleeping. (I had to stop cooking when my husband wasn't home because I kept leaving the burners on.) Since I was recovering from an episode of lactic acidosis (lactate in May was very high, about 12 mmol/L, I had nausea, vomiting, diarrhea, mild respiratory alkalosis and many abnormalities on arterial blood gases, but was not hospitalized), it was suggested that the lactic acidosis might be causing some kind of brain difficulty but the MRI was performed in case it was something else. Leaving out the descriptions of what was normal, the MRI report says, "Supratentorially, several punctate foci of white matter hyperintensity are seen on long TR sequences, located in the subcortical white matter of the left frontal lobe, the left external capsule, and the subcortical white matter of the parietal lobes. A number of dilated periascular spaces are seen in the basal ganglia." (There was also a paranasal sinus inflammatory change and a polyp or retention cyst in one sinus.) Under "Impression" it says the "punctate foci" are "likely representing early foci of small vessel disease." Could this be PML? Or something else? Is this HIV encephalopathy? Do I have dementia? What is "small vessel disease," is this like blocked arteries and potential stroke stuff, or some kind of infection? Might a neurologist's workup be helpful? Could these "punctate foci" and "dilated perivascular spaces" be from the lactic acidosis (lactate has only just returned to normal)? Any chance they'll get better? Anything I can do? Any information would be appreciated. If I knew the name of whatever this is I could read up on it, perhaps make diet, supplement changes, and informed decisions about medication, further investigation. I have been off all meds (except that I am on meds for bipolar illness, and take supplements) since May because of the lactic acidosis.--I was hoping to go back to school to finish my Ph.D. when the mental fuzziness from the (as I thought) lactic acidosis cleared up and am wondering if it will always be harder to think than it used to be and if I should hurry up before my brain gets worse. Thank you.

There is little that is as scary as thinking that you may be losing your ability to think. However, I am not sure that you have much to worry about, although I cannot be sure.

MRI's are wonderfully detailed studies, but they are so detailed that they show many minor changes that are difficult to interpret. This is the case with your study. A neuro-radiologist (that is a radiologist who does nothing other than brain studies) would be far better qualified than I to comment. I am spoiled since we have several of the best here.

The changes you describe are not what is usually seen with HIV dementia and quite different than PML. Your changes are limited to the spaces around the blood vessels. This can be seen with atherosclerosis (hardening of the arteries) and with swelling due to leaky blood vessels. Increased vessel leakiness could certainly be a result of multiple metabolic problems due to lactic acidosis, and can also be seen in other conditions such as vasculitis. Syphilis (so called meningovascular syphilis) could look this way, but I assume your HIV doc checks this periodically with a blood test.

If I had to guess, I would think your doctor would suggest watching for a few weeks as the metabolic changes improve. If you return to normal, that is probably the end of the story. If you still have problems, a neurology consultation, possibly with formal neuropsychological testing would help. (written tests - think of it as doing your GMATS or SATS all over again). It is likely that a repeat MRI would be helpful after a few weeks IF the answers are not already clear.

So, to be clear, my suspicion is that the changes are just those due to the lactic acidosis. You probably will be back to normal and struggling with school again soon. If you have a lot of risk factors for atherosclerosis (smoking, cholesterol, family history, high blood pressure, older age, especially if you are post menopausal) then early small vessel disease is possible but less likely.

Good luck -- hope this helps.

ATP

Andrew T. Pavia, M.D.