Posterior Reversible Encephalopathy Syndrome after Augmentation Cystoplasty in a Child with Neurogenic Bladder.

Posterior reversible encephalopathy syndrome (PRES) or leukoencephalopathy syndrome was introduced into clinical practice in 1996 by Hinchey et al., to describe unique syndrome, clinically expressed during hypertensive and uremic encephalopathy, eclampsia, and immunosuppressive therapy. Hyperperfusion with resultant disruption of the blood-brain barrier results in vasogenic edema, but not infarction, most commonly in the parieto-occipital regions. The severity of this clinical symptom varies. For example, the visual disturbance can manifest as blurred vision, homonymous hemianopsia, or even cortical blindness. Patients may be mildly confused or agitated but can become comatose. Other symptoms less commonly seen include nausea, vomiting, seizures, and brainstem deficits. Chronic kidney disease (CKD) and acute kidney injury are both commonly present in patients with PRES. We are presenting a rare case of neurogenic bladder who developed PRES after augmentation cystoplasty due to underlying CKD.

INTRODUCTION

Posterior reversible encephalopathy syndrome (PRES) or leukoencephalopathy syndrome was introduced into clinical practice in 1996 by Hinchey et al., to describe unique syndrome, clinically expressed during hypertensive and uremic encephalopathy, eclampsia, and immunosuppressive therapy.[12] PRES is a neurotoxic state that occurs secondary to the inability of the posterior circulation to autoregulate in response to acute changes in blood pressure. Hyperperfusion with resultant disruption of the blood–brain barrier results in vasogenic edema, but not infarction, most commonly in the parieto-occipital regions. PRES presents with rapid onset of symptoms including headache, seizures, altered consciousness, and visual disturbance.[34]

CASE REPORT

An 8-year-old male child who was operated for meningomyelocele presented to our department on June 6, 2017. The child had a history of urinary incontinence for the last 2 years and severe constipation since the time of surgery. Clinical examination of the child revealed a severe symptomatic anemia, multiple scars in lumbosacral area, insensate urethra, and a loaded rectum. The child had a weight of 19 kg, height of 147 cm, and blood pressure of 100/50 mm/hg. Baseline laboratory investigations revealed hemoglobin of 6.6 g/dl; serum urea of 140 mg/dl; serum creatinine of 3.74 mg/dl; 24-h urinary protein of 0.1 g/l; and normal serum calcium, magnesium, electrolytes, and arterial blood gas analysis. Ultrasound abdomen revealed bilateral Grade III hydroureteronephrosis with thick-walled trabeculated bladder. Micturating cystourethrography showed small capacity trabeculated bladder, oblong in shape with no reflux. A urodynamics and uroflowmetry were done. The child was diagnosed as a case of neurogenic bladder with chronic kidney disease (CKD).

The child was catheterized. Nephrology consultation was sought, and the advice was followed. The child was planned for augmentation cystoplasty and Mitrofanoff procedure using appendix. After proper optimization, an augmentation colocystoplasty with a bladder drainage procedure was done on June 11, 2017. The child behaved well till 12th postoperative day while still being in the hospital he started having rapid onset of symptoms such as headache, seizures, altered consciousness, and visual disturbances. Pediatric medicine consultation was sought suspecting metabolic derangement which usually follows a colocystoplasty. The child's metabolic profile was normal which ruled out a metabolic cause. A cerebrospinal fluid examination was done to rule out an infective cause. The child was not on any specific drugs responsible for the above clinical picture. The child was diagnosed as having hypertensive encephalopathy with seizures. Magnetic resonance imaging (MRI) brain was done which showed features of PRES [Figure 1]. The child was managed as PRES with labetalol infusion, intravenous phenytoin, and mannitol on pediatric medicine side for 7 days. The child was shifted back to pediatric surgery on June 30, 2017, on oral antihypertensives with a controlled blood pressure. The child was discharged on July 1, 2017, on oral antihypertensives, and a clean intermittent self-catheterization program was started. Nephrology follow-up was advised. Strict monitoring of blood pressure was advised on discharge.

Figure 1

Magnetic resonance imaging shows the distribution of subcortical edema typically involving the posterior frontal, parietal, and occipital lobes

DISCUSSION

The severity of this clinical symptom varies. For example, the visual disturbance can manifest as blurred vision, homonymous hemianopia, or even cortical blindness.[4] Patients may be mildly confused or agitated but can become comatose.[4] Other symptoms less commonly seen include nausea, vomiting, and brainstem deficits.[24] CKD and acute kidney injury are both commonly present in patients with PRES.[5]

Seizures and status epilepticus are common, and nonconvulsive status epilepticus may be more frequent than generalized status epilepticus.[6] Peak systolic blood pressure is usually between 170 and 190 mmHg,[45] but 10%–30% of patients have normal or only mildly elevated blood pressure.[45] In a large series of cases recording the comorbidities of patients with PRES, more than half the patients had chronic hypertension and 38% had CKD.[5] Uncontrolled hypertension leads to hyperperfusion and cerebral vessel damage, resulting in interstitial extravasation of proteins and fluids, causing vasogenic edema.[7] Irreversible damage is seen at mean arterial pressures above 200 mmHg.[7]

Computed tomography (CT) and MRI are helpful in diagnosis. Brain MRI better detects smaller focal abnormalities than brain CT. The most often neuroradiological finding is relatively symmetrical edema of white cerebral tissue in parieto-occipital regions of both cerebral hemispheres. Gray cerebral tissue is sometimes involved, usually in mild form of disease. Diagnosis of this “cortical” form of PRES is possible by MR fluid-attenuated inversion recovery technique.[8] If promptly recognized and treated, the clinical syndrome usually resolves within a week,[24] and the changes seen in MRI resolve over days to weeks.[245] The differential diagnosis of PRES includes broad-venous sinus thrombosis, subdural, intracerebral, subarachnoid hemorrhage.

The posterior encephalopathy syndrome needs to be recognized promptly. The syndrome is usually reversible within 7 days, after controlling the blood pressure. Delay in initiating the appropriate treatment may result in permanent damage to the brain. Patients experiencing seizures become seizure free after resolution of imaging abnormalities and do not require chronic antiepileptic treatment. Therapeutic strategy depends on the cause of PRES and clinical picture. Most important are blood pressure regulation (labetalol, nitroprusside, and diuretics), control of epileptic attacks (phenytoin), and antiedema therapy (mannitol).[9] A systematic follow-up of these patients is essential.

PRES is not uncommon in pediatric nephrology. Hypertension, renal disease, immunosuppression, and chemotherapy of malignancies are triggers for PRES. It is important to consider this diagnosis in children presenting with seizure, visual disturbances, headache, and altered mentation in appropriate clinical setting.[10]

In children presenting with new-onset seizures and systemic hypertension, a pediatric neurologists should consider PRES within a comprehensive differential diagnosis of acute encephalopathy. Early recognition and intensive care are essential for a completely reversible outcome in critically ill children with PRES.[11]

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

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