Vein of Galen Malformations in adults.

OBJECTIVE: Vein of Galen Malformations (VoGM) are rare vascular malformations, typically seen in pediatric age groups. Even more rarely, VoGM's may be seen later in adulthood. In this case report and systematic review, we provide a thorough description of the current literature as well as provide a case example exploring the diagnosis, imaging, treatment, and management of VoGM in adults. METHODS: In accordance with PRISMA guidelines, we performed a systematic literature search for all relevant cases and case series of VoGM in adult patients. The reference list of all articles were reviewed for additional relevant cases. Articles were included if they described a VoGM of a patient over the age of 18 years old and published in English. 149 articles were originally identified and 26 described cases met our inclusion criteria. RESULTS: In our literature review we found 26 patients that met our inclusion criteria. We found 14 male patients and 12 female patients. The mean age at presentation was 37.2 years (median=34 years, SD= 13.6 years). The most common presenting symptoms of patient were headache (n = 9), seizure (n = 6), and vomiting (n = 4). Of the 12 cases which clearly reported the subtype of VoGM, the choroidal type was more frequently seen (n = 10) compared to the mural type (n = 2). In 3 patients, the VoGM was thrombosed at time of diagnosis. Of the 26 patients, endovascular treatment was performed most frequently (n = 8) but some received microsurgical treatment (n = 4) or were treated conservatively (n = 6). Other treatment modalities included (ventriculoperitoneal shunt, ventriculostomy) (n = 5). In 3 cases treatment was not specified. In comparison to VoGM seen in pediatric or neonatal populations, VoGM in adults generally resulted in more favorable outcomes with only 2 patients reported to have passed away following treatment. CONCLUSION: VoGM remains a rare finding amongst the adult population. Hence, we described the clinical presentation, treatment modalities, and outcomes of the cases described in the English literature. Perhaps due to the rate of thrombosis and the unique angioarchitecture seen in adult VoGM patients, outcomes were generally more favorable than those described in the literature in pediatric or neonate VoGM patients.

Spontaneous resolution of cerebral arteriovenous malformation after liver transplant: illustrative case.

BACKGROUND: Cerebral arteriovenous malformations (AVMs) have historically been considered congenital lesions with treatment options including surgery, radiation therapy, and observation. Spontaneous resolution of cerebral AVMs remains an exceedingly rare event with poorly understood pathophysiology. MATERIALS AND METHODS: Herein we report a retrospective case review of a 28-year-old man with alcoholic cirrhosis who presented with a seizure 3 weeks after liver transplantation. Neuroimaging confirmed the presence of a Spetzler-Martin grade 2 AVM in the right frontal lobe. Due to the recent liver transplantation, treatment was deferred at the time of initial diagnosis and the patient was observed for a course of 1 year. Follow-up imaging 1 year later showed resolution of the AVM, confirmed by a catheter angiogram. CONCLUSION: Spontaneous resolution of cerebral AVMs is a rare event. Treatment of chronic liver disease resulted in the normalization of angiogenic factors that likely led to AVM resolution. This case provides valuable insight into the vital role of angiogenesis in the natural history of AVMs.

Outcomes With Age Combinations in Living Donor Kidney Transplantation.

INTRODUCTION: Reevaluation of donor criteria, including age, is needed to combat organ shortages, lengthy wait times, and anticipated recipient mortality rates. The purpose of this study was to evaluate donor and recipient (D/R) age combinations and patient and graft survival outcomes. METHODS: Single-organ, living donor kidney transplantations (LDKTs) from 2012 to 2018 were retrospectively reviewed. Donors and recipients were placed into "older" and "younger" age categories of 50 years and above or below age 50, then analyzed with SPSS version 25. RESULTS: We performed 347 LDKTs. Younger-to-older pairings had significantly higher rates of smoking in recipient (53.6%) and hepatitis C (5.5%), but shorter hospital stays (5.3 days). Older-to-younger pairings had the longest hospital stays (7.4 days) but the shortest cold ischemic time (2.3 hours). Notably, there was no significant variance in delayed graft function (first-week dialysis) between groups. Regarding complication rates, only bleeding within 30 days, highest in older-to-older pairings (7.7%), and renal complications, highest in older-to-younger pairings, significantly varied between groups. Interestingly, though younger-to-older cases had the longest mean graft survival time, older kidneys lasted 537 days longer in older recipients than in younger recipients. DISCUSSION: These results indicate there is not a one-size-fits-all approach when considering outcomes of donor/recipient age-pairings in LDKT, as significant correlations did not consistently favor one age-pairing over others. Regardless of age-pairing, LDKT provides gold standard treatment and expands the availability of organs. Future research into the impact of age-pairing on specific variables, national or multicenter studies, and protocol development for evaluating donor/recipient age-pairings is needed.

3-Isopropylmalate is the major endogenous substrate of the Saccharomyces cerevisiae trans-aconitate methyltransferase.

The Saccharomyces cerevisiae Tmt1 gene product is the yeast homologue of the Escherichia coli enzyme that catalyzes the methyl esterification of trans-aconitate, a thermodynamically favored isomer of cis-aconitate and an inhibitor of the citric acid cycle. It has been proposed that methylation may attenuate trans-aconitate inhibition of aconitase and other enzymes of the cycle. Although trans-aconitate is a minor endogenous substrate of the Tmt1 enzyme in extracts of S. cerevisiae, the major endogenous substrate has yet to be identified. We show here that a trimethylsilylated derivative of the major methylated endogenous product of Tmt1 in yeast extracts has an identical gas chromatography retention time and an identical electron impact mass spectrum as one of the two possible monomethyl ester derivatives of (2R,3S)-3-isopropylmalate. (2R,3S)-3-Isopropylmalate is an intermediate of the leucine biosynthetic pathway that shares similar intermediates and reaction chemistry with the portion of the citric acid cycle from oxaloacetate to alpha-ketoglutarate via cis-aconitate. The Tmt1 methyltransferase recognizes (2R,3S)-3-isopropylmalate with similar kinetics as it does trans-aconitate, with respective K(m) values of 127 and 53 microM and V(max) values of 59 and 70 nmol min(-1) mg(-1) of protein in a Tmt1-overexpressed yeast extract. However, we found that isopropylfumarate, the direct homologue of trans-aconitate in the leucine biosynthetic pathway, was at best a very poor substrate for the Tmt1 yeast enzyme. Similarly, the direct homologue of 3-isopropylmalate in the citric acid cycle, isocitrate, is also a very poor substrate. This apparent change in specificity between the intermediates of these two pathways can be understood in terms of the binding of these substrates to the active site. These results suggest that the Tmt1 methyltransferase may work in two different pathways in two different ways: for detoxification in the citric acid cycle and for a possibly novel biosynthetic branch reaction of the leucine biosynthetic pathway.