Posterior reversible encephalopathy syndrome in a patient with systemic lupus erythematosus after cessation of oral prednisone

Arginine Vasopressin and Posterior Reversible Encephalopathy Syndrome Pathophysiology: the Missing Link?

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological entity characterized by a typical brain edema. Its pathogenesis is still debated through hypoperfusion and hyperperfusion theories, which have many limitations. As PRES occurs almost exclusively in clinical situations with arginine vasopressin (AVP) hypersecretion, such as eclampsia and sepsis, we hypothesize that AVP plays a central pathophysiologic role. In this review, we discuss the genesis of PRES and its symptoms through this novel approach. We theorize that AVP axis stimulation precipitates PRES development through an increase in AVP secretion or AVP receptor density. Activation of vasopressin V_1a receptors leads to cerebral vasoconstriction, causing endothelial dysfunction and cerebral ischemia. This promotes cytotoxic edema through hydromineral transglial flux dysfunction and may increase endothelial permeability, leading to subsequent vasogenic brain edema. If our hypothesis is confirmed, it opens new perspectives for better patient monitoring and therapies targeting the AVP axis in PRES.

Influential factors and clinical significance of an atypical presentation of posterior reversible encephalopathy syndrome in patients with eclampsia

BACKGROUND AND PURPOSE

Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiologic entity for which eclampsia is one of the most common predisposing conditions. Despite the imaging changes typically reported, the predisposing factors and clinical implications of atypical presentations have yet to be fully clarified.

METHODS

A total of 56 patients with PRES were selected for study. Demographic, clinical, and laboratory data were analyzed, focusing on atypical presentations of PRES. Multiple logistic regression was applied to identify factors impacting such atypical presentations, and functional outcomes were assessed upon patient discharge.

RESULTS

Overall, 22 of the 56 patients (39.3%) displayed features of atypical PRES. By multiple logistic regression, headache (OR = 5.39; 95% CI, 1.24-23.51; p = 0.025) and frequent convulsions (OR = 4.41; 95% CI, 1.09-17.91; p = 0.038) proved to be independent factors associated with atypical PRES. Ultimately, outcomes of 18 patients were gauged as poor, based on the modified Rankin Scale (mRS). Logistic regression indicated that visual disturbances (OR = 9.02; 95% CI, 1.37-59.35; p = 0.02), frequent convulsions (OR = 9.47; 95% CI, 1.67-53.63; p = 0.01), and restricted diffusion on imaging (OR = 11.96; 95% CI, 1.76-81.11; p = 0.01) were independently associated with poor outcomes in patients with eclampsia-related PRES.

CONCLUSION

Headache and frequent convulsions are independently associated with atypical presentations of PRES. If present, restricted diffusion may help in predicting poor outcomes of such patients upon discharge.

Corticosteroid therapy and severity of vasogenic edema in posterior reversible encephalopathy syndrome

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is a variable cerebrovascular syndrome associated with hypertension and autoregulatory failure. Steroids have been reported to both precipitate and treat PRES. We sought to determine the prevalence of steroid therapy at the time of PRES and to assess the relationship between steroid therapy and extent of vasogenic edema.

METHODS

We performed a retrospective review of radiology reports between 2008 and 2014 from two academic medical centers to identify cases of PRES. Clinical and radiographic data were collected. Descriptive statistics were used to determine the prevalence of corticosteroid therapy at the time of PRES onset and the latency from steroid initiation to PRES onset. The association between steroid therapy and extent of vasogenic edema was assessed in multiple regression models.

RESULTS

We identified 99 cases of PRES in 96 patients. The median age was 55years (IQR 30-65) and 74% were women. Steroid therapy at time of PRES onset was identified in 44 of 99 cases. Excluding patients on chronic therapy, the median duration of steroid exposure before PRES onset was 6 (IQR, 3-10) days. Steroid therapy was not associated with extent of vasogenic edema in unadjusted or linear and logistic regression models adjusted for age, sex, and maximum systolic blood pressure on day of onset.

CONCLUSION

Corticosteroid therapy, often of brief duration, frequently preceded the onset of PRES and was not associated with severity of vasogenic edema.