👤 Melanie Bahlo

We analyzed the genotypic and phenotypic features of patients with psychosis of epilepsy (POE). Patients with POE recruited to an epilepsy genetics research program underwent phenotyping and genetic analysis. The latter included screening for rare pathogenic variants in epilepsy genes, and polygenic risk score (PRS) calculation for common risk variants associated with schizophrenia. One hundred twenty-two individuals with POE were identified. Eighty-six of 122 of the individuals (70%) had interictal psychosis, with schizophrenia the most common interictal phenotype (36/86, 42%). Twenty-eight of 122 of the individuals (23%) had postictal psychosis (PIP), 2 of 122 of the individuals (2%) had antiseizure medication-induced psychosis, and 6 of 122 of the individuals (5%) had substance-induced psychosis. Focal epilepsies were more frequently associated with PIP (24/28, 86%) compared to interictal psychosis (39/86, 45%; p < 0.05). Twenty-nine percent of the patients with POE with genetic data had a rare pathogenic variant: 19 in an epilepsy gene (PCDH19, SCN1A, DEPDC5, KCNT1, CHD2, SLC2A1, NPRL3, CLN3, NPRL3, ATP1A3, and CACNA1A) and 4 had a chromosomal anomaly. Fifty-seven percent of the patients with a rare pathogenic variant had interictal schizophrenia/schizophreniform disorder rather than PIP (9%; p < 0.05). PRSs showed that schizophrenia-related common risk variants were enriched in patients with POE compared to population controls (p = 0.0007), however, among the POE phenotypes, a raised PRS was only observed in interictal schizophrenia (p = 0.015) and not in those with PIP or other interictal POEs. Interictal POE is threefold more common than PIP, and more likely to be associated with both rare pathogenic variants for epilepsy and common risk variants for schizophrenia. Distinguishing between different POE phenotypes enhances clinical practice and our understanding of etiology, paving the way for precision medicine. ANN NEUROL 2025;98:35-47. Show less

Macular Telangiectasia type 2 (MacTel) is an uncommon bilateral retinal disease, in which glial cell and photoreceptor degeneration leads to central vision loss. The causative disease mechanism is largely unknown, and no treatment is currently available. A previous study found variants in genes associated with glycine-serine metabolism (PSPH, PHGDH and CPS1) to be associated with MacTel, and showed low levels of glycine and serine in the serum of MacTel patients. Recently, a causative role of deoxysphingolipids in MacTel disease has been established. However, little is known about possible other metabolic dysregulation. Here we used a global metabolomics platform in a case-control study to comprehensively profile serum from 60 MacTel patients and 58 controls. Analysis of the data, using innovative computational approaches, revealed a detailed, disease-associated metabolic profile with broad changes in multiple metabolic pathways. This included alterations in the levels of several metabolites that are directly or indirectly linked to glycine-serine metabolism, further validating our previous genetic findings. We also found changes unrelated to PSPH, PHGDH and CPS1 activity. Most pronounced, levels of several lipid groups were altered, with increased phosphatidylethanolamines being the most affected lipid group. Assessing correlations between different metabolites across our samples revealed putative functional connections. Correlations between phosphatidylethanolamines and sphingomyelin, and glycine-serine and sphingomyelin, observed in controls, were reduced in MacTel patients, suggesting metabolic re-wiring of sphingomyelin metabolism in MacTel patients. Our findings provide novel insights into metabolic changes associated with MacTel and implicate altered lipid metabolism as a contributor to this retinal neurodegenerative disease. Show less