Uremic encephalopathy in patients undergoing assisted peritoneal dialysis: a case series and literature review

Magnetic Resonance Imaging in Uremic Encephalopathy: Identifying Key Imaging Patterns and Clinical Correlations

Background/Objectives: Magnetic Resonance Imaging (MRI) is essential in diagnosing neurological conditions, offering detailed insights into brain pathology. Uremic encephalopathy (UE) is a severe neurological disorder resulting from renal failure, characterized by cognitive impairments and brain abnormalities due to the accumulation of uremic toxins (UTs). Despite extensive research on UTs, there is a significant gap in the detailed characterization of MRI findings in UE patients. This study aims to bridge this gap by conducting a comprehensive literature review of cerebral MRI findings in UE. We hypothesize that specific MRI patterns correlate with the severity and clinical manifestations of UE, thereby enhancing diagnostic accuracy and improving patient outcomes. Methods: A literature review was performed using PubMed, Cochrane Library, and Google Scholar. The search terms included "uremic encephalopathy MRI", "uremia and kidney failure MRI", and "toxic and metabolic or acquired encephalopathies MRI". The inclusion criteria were original articles on UE and MRI findings published in English. Results: Common MRI sequences include T1-weighted, T2-weighted, FLAIR, and DWI. Frequent MRI findings in UE are cytotoxic and vasogenic brain edema in regions such as the basal ganglia and periventricular white matter. Patterns like the "lentiform fork sign" and basal ganglia involvement are key indicators of UE. Conclusions: MRI plays a crucial role in diagnosing UE by identifying characteristic brain edema and specific patterns. A comprehensive diagnostic approach, incorporating clinical, laboratory, and imaging data, is essential for accurate diagnosis and management. The study calls for larger well-designed cohorts with long-term follow-up to improve the understanding and treatment of UE.

circRNA-PTPN4 mediated regulation of FOXO3 and ZO-1 expression: implications for blood-brain barrier integrity and cognitive function in uremic encephalopathy

Uremic encephalopathy (UE) poses a significant challenge in neurology, leading to the need to investigate the involvement of non-coding RNA (ncRNA) in its development. This study employed ncRNA-seq and RNA-seq approaches to identify fundamental ncRNAs, specifically circRNA and miRNA, in the pathogenesis of UE using a mouse model. In vitro and in vivo experiments were conducted to explore the circRNA-PTPN4/miR-301a-3p/FOXO3 axis and its effects on blood-brain barrier (BBB) function and cognitive abilities. The research revealed that circRNA-PTPN4 binds to and inhibits miR-301a-3p, leading to an increase in FOXO3 expression. This upregulation results in alterations in the transcriptional regulation of ZO-1, affecting the permeability of human brain microvascular endothelial cells (HBMECs). The axis also influences the growth, proliferation, and migration of HBMECs. Mice with UE exhibited cognitive deficits, which were reversed by overexpression of circRNA-PTPN4, whereas silencing FOXO3 exacerbated these deficits. Furthermore, the uremic mice showed neuronal loss, inflammation, and dysfunction in the BBB, with the expression of circRNA-PTPN4 demonstrating therapeutic effects. In conclusion, circRNA-PTPN4 plays a role in promoting FOXO3 expression by sequestering miR-301a-3p, ultimately leading to the upregulation of ZO-1 expression and restoration of BBB function in mice with UE. This process contributes to the restoration of cognitive abilities.

Toxic and metabolic leukoencephalopathies in emergency department patients: a primer for the radiologist

One of the most common chief complaints in the emergency department (ED) is altered mental status (AMS). Imaging plays a critical role in triaging patients and identifying the etiology of AMS. Toxic and metabolic etiologies are one of the primary differential categories for AMS, leading to toxic leukoencephalopathies. Toxic leukoencephalopathies are white matter disorders that result from either exogenous or endogenous sources. Common exogeneous causes of toxic leukoencephalopathy include drugs of abuse (heroin and cocaine), alcohol, inhaled gases (carbon monoxide), industrial agents (pesticides, toluene, ethylene glycol), and neurotoxic medications (methotrexate, metronidazole, vigabatrine, etc.); endogenous causes include hyper- and hypoglycemia, hyperammonemia, hyponatremia, and uremia. The imaging findings of toxic leukoencephalopathies manifest through a combination of vasogenic and cytotoxic edema, resulting in white matter patterns. These white matter patterns have been found to be pathognomonic. In the ED setting, it is imperative to develop a diagnosis based off of the imaging due to the lack of history and context that is typically provided with a chief complaint of altered mental status (AMS). To offer expeditious and accurate diagnosis, we present the classic imaging features of toxic leukoencephalopathies and correlate these imaging findings with pathophysiology.

Effects of exercise on residual renal function in patients undergoing peritoneal dialysis: A post-hoc analysis of a randomized controlled trial

We aimed to investigate the effects of exercise on renal outcomes in patients undergoing peritoneal dialysis (PD). In a post-hoc analysis of a randomized controlled trial of a 12-week home-based exercise program involving 47 patients undergoing PD, we excluded 18 patients with anuria and analyzed 13 and 16 patients in the usual care and exercise groups, respectively. The primary outcomes were weekly renal creatinine clearance (CCr) and urinary biomarkers: liver-type fatty acid-binding protein (L-FABP) and the microalbumin-to-creatinine ratio (ACR). Although the maintenance of weekly renal CCr in the exercise group was not significantly different compared with that in the usual care group (P = .09), urinary L-FABP levels (P = .02) and ACR (P = .04) were significantly decreased in the exercise group. To the best of our knowledge, this is the first study to demonstrate the beneficial effects of exercise on renal outcomes in patients undergoing PD.