Uremic encephalopathy with isolated brainstem involvement revealed by magnetic resonance image: a case report

Abstract

BackgroundUremic Encephalopathy (UE) is a neurological complication associated with acute or chronic renal failure. Imaging findings of UE may present involvement of the basal ganglia, cortical or subcortical regions, and white matter. We report a rare case of UE caused by neurogenic bladder with isolated brainstem involvement revealed by magnetic resonance imaging (MRI). Immediate therapy resulted in full recovery of neurological signs and changes on MRI.Case presentationA 14-year-old Han Chinese woman with a history of chronic renal failure caused by neurogenic bladder. On admission, she was unconscious and her pupils presented different sizes, while her vital signs were normal. MRI showed high signal in the dorsal pontine base and in the mid brain on fluid-attenuated inversion-recovery (FLAIR) imaging and on T2-weighted imaging while the signal was normal on diffusion-weighted images (DWI). Blood analysis revealed renal failure and acidosis. After urinary retention treatment and acidosis correction, the patient soon recovered. Follow-up MRI 2 months after the discharge revealed complete resolution of UE in the brainstem.ConclusionWe reported a rare case of a patient with UE that had unusual imaging manifestations for whom timely diagnosis and treatment assured recovery.

Isolated pan‐pontine posterior reversible encephalopathy syndrome in a patient with uncontrolled hypertension

“…Furthermore, because our patient had a history of CKD (as many others suffering from PRES do) the question was raised as to whether or not she was in fact suffering from central PRES at all, and instead from uremic encephalopathy (UE). UE typically involves cortical regions, although exclusive basal ganglia and brainstem involvement have been known to occur, which mimics central PRES on FLAIR MRI . Although the pathophysiological changes between both PRES and UE are not fully understood (purposed autoregulation failure in the former, and toxin mediated in the latter), both result in breakdown of the blood‐brain barrier and subsequent vasogenic edema noted on FLAIR MRI as hyperintense signaling, without DWI findings .…”

“…Due to the vulnerability of the pons in this setting, the fact that our patient waited an entire week before presenting to the ED may be the reason why the pons was so severely affected in comparison with the basal ganaglia, thalami, cerebellum, and midbrain. Although the patient from the Gao study also suffered from CKD, the fact that he presented a day after the onset of symptoms may account for why only the pons was affected, and additional involvement of other areas typical for central PRES may have occurred if he had waited. Further studies to determine whether or not CKD is significantly associated with an increased risk of pontine involvement in patients presenting with central PRES are warranted.…”

“…6 Although the pathophysiological changes between both PRES and UE are not fully understood (purposed autoregulation failure in the former, and toxin mediated in the latter), both result in breakdown of the blood-brain barrier and subsequent vasogenic edema noted on FLAIR MRI as hyperintense signaling, without DWI findings. 6 Although both conditions are known to improve with hemodialysis (as a last resort if medical therapy is unsuccessful at controlling blood pressure in PRES patients), we believe that the major contributing factor causing pan-pontine hyperintense signaling was due to hypertension, with urea most likely playing an exacerbation part. Although her creatinine and BUN were both elevated on admission (3.2 and 52, respectively), our patient was never acidotic, she did not display signs of asterixis at any point, and cortical regions typical of UE were not involved, factors which lead us to believe the culprit was high blood pressure.…”

“…UE typically involves cortical regions, although exclusive basal ganglia and brainstem involvement have been known to occur, which mimics central PRES on FLAIR MRI . Although the pathophysiological changes between both PRES and UE are not fully understood (purposed autoregulation failure in the former, and toxin mediated in the latter), both result in breakdown of the blood‐brain barrier and subsequent vasogenic edema noted on FLAIR MRI as hyperintense signaling, without DWI findings . Although both conditions are known to improve with hemodialysis (as a last resort if medical therapy is unsuccessful at controlling blood pressure in PRES patients), we believe that the major contributing factor causing pan‐pontine hyperintense signaling was due to hypertension, with urea most likely playing an exacerbation part.…”

Case report: MRI findings of acute uremic encephalopathy in a 1-year-old boy

“…The cause is attributable to the accumulation of uremic toxins, such as creatinine and guanidine, which have the ability to activate the neurotoxic effect of NMDA receptors. 1 UE has been well-documented in the adult population, 2 but appears to be very rare in the paediatric population 3,4 . After a detailed literature review, to our knowledge, there are no case reports describing bilateral basal ganglia (BG) involvement in a non-diabetic, paediatric patient with no prior history of renal impairment.…”