Posterior reversible encephalopathy syndrome in (low renin) essential hypertension

Etiologies, Cerebral Vasomotion, and Endothelial Dysfunction in the Pathophysiology of Posterior Reversible Encephalopathy Syndrome in Pediatric Patients

The posterior reversible encephalopathy syndrome was characterized by Hinchey and colleagues in the 1990s. The condition frequently afflicts patients suffering from hematologic and solid organ malignancy and individuals undergoing transplantation. Cases are more frequently described in the adult population compared with children. In the pediatric population, malignancy, transplantation, renal disease, and hypertension represent the most common etiologies. Theories on pathogenesis have centered upon cerebrovascular dysautoregulation with increases in blood–brain barrier permeability. This generates vasogenic edema of the cerebral parenchyma and consequent neurologic deficits. The parietal and occipital lobes are affected with greatest prevalence, though frontal and temporal lobe involvement is frequent, and that of the contents of the infratentorial posterior cranial fossa are occasionally described. The clinical presentation involves a characteristic constellation of neurologic signs and symptoms, most typically inclusive of headache, visual-field disturbances, abnormalities of visual acuity, and seizures. Supportive care, withdrawal of the offending agent, antihypertensive therapy, and prophylactic anticonvulsants affect convalescence in majority of cases. The principal challenge lies in identifying the responsible agent precipitating the condition in patients with malignancy and those having undergone transplantation and thus deciding which medication among a multidrug treatment regimen to withhold, the duration of drug cessation required to effect clinical resolution, and the safety of resuming treatment with the compound. We accordingly reviewed and evaluated the literature discussing the posterior reversible encephalopathy syndrome in children.

Calcimimetic R568 reduced the blood pressure and improved aortic remodeling in spontaneously hypertensive rats by inhibiting local renin-angiotensin system activity

Hypertension is a cardiovascular disease that seriously affects human health. Activation of the calcium-sensing receptor (CaSR) inhibits cyclic adenosine monophosphate (cAMP) formation by increasing [Ca²⁺]_i and subsequently inhibiting renin release. The renin-angiotensin system (RAS) plays an important role in the development of essential hypertension (EH). The purpose of this study was to determine the effects of NPSR568 (R568)-activated CaSR on blood pressure (BP), proliferation, and remodeling of vascular smooth muscle cells, and the activity of the RAS in spontaneously hypertensive rats (SHRs). In this study, we treated SHR and Wistar-Kyoto rats with R568 for 8 weeks. The tail-cuff method was used to assess rat BP weekly. Morphological changes in the thoracic aorta were evaluated with hematoxylin-eosin and Masson staining. Western blotting and immunohistochemistry were used to detect the expression of RAS-related proteins and proliferative remodeling proteins in the thoracic aorta. An enzyme-linked immunosorbent assay was used to detect the content of cAMP, the RAS, and the CaSR in plasma and the thoracic aorta. Finally, we found that treatment with R568 for 8 weeks reduced the BP and inhibited arterial vascular proliferation remodeling in SHRs. R568 administration significantly suppressed the activity of local RAS in the thoracic aortas of SHRs. Moreover, R568 treatment reversed the low expression of CaSR in SHRs. R568 may serve as an effective strategy against EH.

Posterior reversible encephalopathy syndrome presenting as Balint syndrome

Balint syndrome is a disorder of inaccurate visually guided saccades, optic ataxia, and simultanagnosia that typically results from bilateral parieto-occipital lesions. Visual perception disturbances in the posterior reversible encephalopathy syndrome (PRES) include hemianopia, visual neglect, and cerebral blindness, but Balint syndrome had not been recognized. We report Balint syndrome associated with PRES in a 37-year-old woman with acute hypertension and systemic lupus erythematosus. Balint syndrome can be an initial presentation of PRES.