Posterior reversible encephalopathy syndrome (PRES) is a rare clinic-radiological disease entity . Herein, we report a case of PRES in a 34 years man, who came to our urological clinic for further management of persistent urine retention following prior laser prostatectomy one month ago at other hospital with pathology of prostatic sarcoma. Magnetic resonance imaging (MRI) disclosed huge prostate gland (12.4x8.8x8.5 cm) with invasion to prostate apex, right corpus spongiosum, inferior wall of urinary bladder, left anterior wall of rectum and left iliococcygeal muscle, compatible with sarcoma. He underwent en bloc resection of tumor with anterior pelvic exenteration and bilateral ureter ligation with final pathology of undifferentiated high grade sarcoma of prostate and urinary bladder.

The patient had smooth endotracheal extubation after surgery and could obey order. However, he developed sudden loss of consciousness, hypoxia and pulseless during transportation to POR. Immediate CPR and endotracheal intubation were administered. Following resuscitation for three minutes, he did not regain consciousness and persistent hypertension with upgazed, dilated pupil were noted. The creatinine level was 1.61 mg/dL, the lactate level was 132.5 mg/dL and ammonia level was 62 ug/dL. After bilateral percutaneous nephrostomy (PCN) tubes placement, he was transferred to ICU for further intensive care. Brain CT showed no signs of intracranial hemorrhage or ischemia. Neurologist was consulted and posterior reversible encephalopathy syndrome (PRES) was impressed since there was no evidence of hypoxic encephalopathy. He regained consciousness and had smooth extubation following supportive treatment with hypertension control and adequate hydration. He was transferred back to ordinary ward after 8 days of ICU stay. After rehabilitation, all of the troublesome sequelae of swallowing difficulty, non-fluent or expressive aphasia, impaired fine motor function, visual field defect, and stamina gradually improved. The patient was discharged in stable condition and received adjuvant therapy at medical and radiation oncology department.

Discussion

PRES is a rare disease with only few case reports. Common symptoms and signs include headache, decreased consciousness, hemianopia, visual neglect or seizure. Pathogenesis remained unclear but might be related to disordered cerebral autoregulation or endothelial dysfunction. Anatomical distribution was at subcortical white matter in the posterior cerebral hemispheres. Risk factors include hypertension, immunosuppressive drugs (such as Cyclosporine, platinum-containing drugs, Sunitinib…etc.), and renal diseases. Imaging findings were white matter edema in posterior cerebral hemispheres on CT; hypointense signals on diffusion weighted imaging (DWI) and hyperintense signals on apparent diffusion coefficient (ADC) on MRI. The mainstay of treatment is to control hypertension with acute-onset drugs and seizure management.

Conclusion

        Back to our patient, he was overweight with BMI 27.4 and require more anesthetics, besides, bilateral ureter ligation may affect drug excretion and prolong recovery from anesthesia. Agitation during extubation may also induce high blood pressure, which is the major risk factor of PRES.

In conclusion, we recommend keeping high suspicion in patients with these potential risk factors before surgery as the mainstay for the diagnosis of postoperative PRES, and prompt treatment following the diagnosis of PRES may reduce morbidity and early recovery.