CASE 13395 Published on 11.02.2016

Posterior reversible encephalopathy syndrome (PRES) in a patient with end-stage renal disease.



Case Type

Clinical Cases


Anastasia Zikou1, Geogia Mouka1, Dionysios Toliopoulos1, Vasileios Xydis1, Olga Balafa2, Eleni Ermeidi2, Maria I Argyropoulou1.

1. Department of Clinical Radiology, Medical School of Ioannina, Greece.
2. Department of Nephrology, University Hospital of Ioannina, Greece.

45 years, female

Area of Interest Neuroradiology brain ; Imaging Technique MR
Clinical History
A 45 year-old woman with end stage renal disease from IgA nephropathy, three weeks after outset of peritoneal dialysis (PD) presented with acute headache, diplopia, generalized tonic–clonic seizures. She had hypertension [200/120 mmHg] and inadequate management of fluid balance. A brain magnetic resonance imaging (MRI) was performed.
Imaging Findings
Brain MRI revealed on FLAIR images (Fig.1 a, b, c), T2 images (Fig.2 a, b, c, d) and ADC maps (Fig. 2 e, f, g, k), bilateral, relatively symmetrical high-signal foci in the subcortical white matter parieto-occipitally compatible with vasogenic oedema. This is the so-called ‘classic’ pattern of PRES.
The patient received phenytoin and gradually improved her symptomatology, while intensified PD treatment intended to reduction of fluid overload. The follow up MRI two months after the incident showed rapid resolution of the lesions (Fig.1 d, e, f), (Fig.3).
Posterior reversible encephalopathy syndrome (PRES) was first introduced by Hinchey et al. in 1996 to describe a reversible syndrome presenting with headache, altered mental functioning, seizures, and visual disturbances accompanied by characteristic neuroimaging findings in acutely hospitalized patients [1]. Complete remission of the symptoms and radiologic findings occur after appropriate treatment [2-5]. This syndrome is observed in numerous clinical conditions such as nephrotic syndrome, acute poststreptoccocal gromeluronephritis, diffuse mesangial sclerosis, solid organ transplantation, bone marrow and stem cells transplantation, eclampsia, critically ill patients, systemic lupus erythematosus, hemolytic uremic syndrome [6].
The most typical clinical presentation of PRES includes headache, visual disturbances, generalized tonic-clonic or partial seizures, altered mental function ranging from mild somnolence to frank confusion, stupor or coma [3, 7,8]. In 70% to 80% of patients PRES have moderate to severe hypertension while in 20% to 30% the BP is normal or minimally elevated. Symptoms have gradual or acute onset, are not specific and can mimic a variety of neurological conditions which should be excluded [9, 10].
The typical neuroimaging presentation of PRES is vasogenic edema predominantly involving the posterior white matter of the cerebral hemispheres, especially the bilateral parieto-occipital lobes. The imaging abnormalities are not isolated only in the posterior parieto-occipital white matter but can also involve the cortex, the frontal lobes, the basal ganglia, and the brainstem [11-14]. Complete resolution of the abnormalities is observed 8 days to 17 months after appropriate treatment
Two hypotheses have been proposed for the pathogenesis of the syndrome. The current theory suggests that severe hypertension exceeds the limits of autoregulation, leading to blood vessel alteration, capillary bed injury, hyperperfusion and brain edema [14-17]. The early original theory of vasoconstriction, hypoperfusion and ischemia traditionally suggests that vasoconstriction secondary to hypertension and autoregulatory compensation leads to reduced brain perfusion, ischemia, and subsequent vasogenic edema [16-17]. None of them could completely explain the cascade of events leading this syndrome.
Conclusion: PD patients tend to be overhydrated comparing with haemodialysis patients. Nephrologists should be aware of PRES syndrome, especially when they manage hypertensive ESRD patients non-compliant with the fluid and diet restrictions. MRI is the only diagnostic tool for defining this syndrome. Early diagnosis is important, since complete remission is achieved after appropriate treatment.
Differential Diagnosis List
Posterior reversible encephalopathy syndrome.
• Progressive multifocal leukoencephalopathy
• Severe hypoglycemic encephalopathy
• Posterior circulation stroke
• Hypoxic-ischemic encephalopathy
Final Diagnosis
Posterior reversible encephalopathy syndrome.
Case information
DOI: 10.1594/EURORAD/CASE.13395
ISSN: 1563-4086