Thiamine Supplementation in Patients With Alcohol Use Disorder Presenting With Acute Critical Illness : A Nationwide Retrospective Observational Study.

BACKGROUND: Thiamine supplementation is recommended for patients with alcohol use disorder (AUD). The authors hypothesize that critically ill patients with AUD are commonly not given thiamine supplementation. OBJECTIVE: To describe thiamine supplementation incidence in patients with AUD and various critical illnesses (alcohol withdrawal, septic shock, traumatic brain injury [TBI], and diabetic ketoacidosis [DKA]) in the United States. DESIGN: Retrospective observational study. SETTING: Cerner Health Facts database. PATIENTS: Adult patients with a diagnosis of AUD who were admitted to the intensive care unit with alcohol withdrawal, septic shock, TBI, or DKA between 2010 and 2017. MEASUREMENTS: Incidence and predicted probability of thiamine supplementation in alcohol withdrawal and other critical illnesses. RESULTS: The study included 14 998 patients with AUD. Mean age was 52.2 years, 77% of participants were male, and in-hospital mortality was 9%. Overall, 7689 patients (51%) received thiamine supplementation. The incidence of thiamine supplementation was 59% for alcohol withdrawal, 26% for septic shock, 41% for TBI, and 24% for DKA. Most of those receiving thiamine (n = 3957 [52%]) received it within 12 hours of presentation in the emergency department. The predominant route of thiamine administration was enteral (n = 3119 [41%]). LIMITATION: Specific dosing and duration were not completely captured. CONCLUSION: Thiamine supplementation was not provided to almost half of all patients with AUD, raising a quality-of-care issue for this cohort. Supplementation was numerically less frequent in patients with septic shock, DKA, or TBI than in those with alcohol withdrawal. These data will be important for the design of quality improvement studies in critically ill patients with AUD. PRIMARY FUNDING SOURCE: National Institutes of Health.

Implication of folate deficiency in CYP2U1 loss of function.

Hereditary spastic paraplegias are heterogeneous neurodegenerative disorders. Understanding of their pathogenic mechanisms remains sparse, and therapeutic options are lacking. We characterized a mouse model lacking the Cyp2u1 gene, loss of which is known to be involved in a complex form of these diseases in humans. We showed that this model partially recapitulated the clinical and biochemical phenotypes of patients. Using electron microscopy, lipidomic, and proteomic studies, we identified vitamin B2 as a substrate of the CYP2U1 enzyme, as well as coenzyme Q, neopterin, and IFN-α levels as putative biomarkers in mice and fluids obtained from the largest series of CYP2U1-mutated patients reported so far. We also confirmed brain calcifications as a potential biomarker in patients. Our results suggest that CYP2U1 deficiency disrupts mitochondrial function and impacts proper neurodevelopment, which could be prevented by folate supplementation in our mouse model, followed by a neurodegenerative process altering multiple neuronal and extraneuronal tissues.

Bi-allelic GOT2 Mutations Cause a Treatable Malate-Aspartate Shuttle-Related Encephalopathy.

Early-infantile encephalopathies with epilepsy are devastating conditions mandating an accurate diagnosis to guide proper management. Whole-exome sequencing was used to investigate the disease etiology in four children from independent families with intellectual disability and epilepsy, revealing bi-allelic GOT2 mutations. In-depth metabolic studies in individual 1 showed low plasma serine, hypercitrullinemia, hyperlactatemia, and hyperammonemia. The epilepsy was serine and pyridoxine responsive. Functional consequences of observed mutations were tested by measuring enzyme activity and by cell and animal models. Zebrafish and mouse models were used to validate brain developmental and functional defects and to test therapeutic strategies. GOT2 encodes the mitochondrial glutamate oxaloacetate transaminase. GOT2 enzyme activity was deficient in fibroblasts with bi-allelic mutations. GOT2, a member of the malate-aspartate shuttle, plays an essential role in the intracellular NAD(H) redox balance. De novo serine biosynthesis was impaired in fibroblasts with GOT2 mutations and GOT2-knockout HEK293 cells. Correcting the highly oxidized cytosolic NAD-redox state by pyruvate supplementation restored serine biosynthesis in GOT2-deficient cells. Knockdown of got2a in zebrafish resulted in a brain developmental defect associated with seizure-like electroencephalography spikes, which could be rescued by supplying pyridoxine in embryo water. Both pyridoxine and serine synergistically rescued embryonic developmental defects in zebrafish got2a morphants. The two treated individuals reacted favorably to their treatment. Our data provide a mechanistic basis for the biochemical abnormalities in GOT2 deficiency that may also hold for other MAS defects.