Hippocampal neurometabolic and structural changes from pre-to post-COVID-19: A case-series study

BACKGROUND

Neurological complications of the COVID-19 infection may be caused in part by local neurochemical and structural abnormalities that could not be detected during routine medical examinations. We examined within subject neurometabolic and structural brain alterations from pre-to post-COVID-19 in the hippocampal region of three elderly individuals (aged 63-68 years) who had a COVID-19 infection with mild symptoms. Patients were participating in an interventional study in which they were closely monitored at the time they were diagnosed with COVID-19. Patients 1 and 2 just completed 18-20 resistance training sessions prior to their diagnosis. Patient 3 was assigned to a non-training condition in the same study.

METHODS

Whole brain magnetic resonance imaging (MRI) images and proton magnetic resonance spectroscopy (1H-MRS) of the left hippocampus were collected before and after infection. Structural and spectroscopic imaging measures post-COVID-19 were contrasted to the pre-COVID-19 measures and were compared with values for Minimal Detectable Change at 95% (MDC95) and 90% (MDC90) confidence from a group of six elderly (aged 60-79 years) without COVID-19 that participated in the same study.

RESULTS

After SARS-COV-2 infection, we observed a reduction of glutamate-glutamine (Glx) in Patients 1 and 2 (≥ 42.0%) and elevation of myo-inositol (mIns) and N-acetyl-aspartate (NAA) in Patient 3 (≥ 36.4%); all > MDC90. MRI findings showed increased (Patients 1 and 2) or unchanged (Patient 3) hippocampal volume.

CONCLUSIONS

Overall, findings from this exploratory study suggest that mild COVID-19 infection could be associated with development of local neuroinflammation and reduced glutamate levels in the hippocampus. Our 1H-MRS findings may have clinical value for explaining chronic neurological and psychological complaints in COVID-19 long-haulers.

Creutzfeldt-Jakob disease with neuroleptic malignant syndrome

Creutzfeldt‐Jakob disease (CJD) is a rare rapidly progressive fatal neurodegenerative disease. Neuroleptic malignant syndrome (NMS) is a complication of antipsychotic medications which may be used to treat neuropsychiatric symptoms of CJD. We present a case of a 51‐year‐ old woman with CJD who developed NMS after being prescribed quetiapine.

Different MRI-defined tuber types in tuberous sclerosis complex: Quantitative evaluation and association with disease manifestations

BACKGROUND

Tuberous sclerosis complex (TSC) is a rare genetic disorder with multisystem involvement. A magnetic-resonance (MRI) based classification of tubers into types A, B and C has been proposed. However, the relationship between different tuber types and their quantitative characteristics, also the non-neurological manifestations of TSC remains unknown.

AIMS

To quantitatively evaluate different MRI-defined tuber types and to explore their relationships with major disease manifestations in patients with tuberous sclerosis complex.

METHODS

We performed quantitative manual assessment of tubers visible on T1W, T2W/FLAIR images and DW/ADC maps of 20 patients with TSC. Tubers were classified into types A, B and C based on their signal intensity on MRI. General clinical information and quantitative tuber characteristics were evaluated. Between-group comparisons were made using the nonparametric Mann-Whitney U test with Bonferroni correction.

RESULTS

In total, 20 patients with 770 tubers were evaluated. Type A tubers were most numerous followed closely by Type B tubers, whereas Type C tubers were relatively rare. Tuber size was markedly different among the three tuber types: it increased from Type A to Type B to Type C. Infantile spasms, generalized-tonic clonic seizures, poor seizure control, cardiac rhabdomyomas, SEGA and developmental delay were not associated with quantitative tuber characteristics. Increased total Type B tuber load was associated with early onset epilepsy, while individually larger Type A and Type B tubers were associated with the presence angiomyolipoma (AML) and renal cysts.

CONCLUSIONS

MRI-defined tuber types differ significantly in their size and number. Larger total Type B tuber load and larger individual Type A and Type B tubers were found to be most associated with early seizure onset and renal angiomyolipomas, respectively. One possible explanation for the observed differences in the clinical phenotype based on MRI-defined tuber types is not the intrinsic qualitative distinctions between different tuber types, but rather their individual size and total tuber load.