Challenges of Diagnosing Pediatric Posterior Reversible Encephalopathy Syndrome in Resource Poor Settings: A Narrative Review

Pediatric Posterior Reversible Encephalopathy Syndrome: A Review With Emphasis on Neuroimaging Characteristics

Posterior reversible encephalopathy syndrome (PRES) is a neurological disorder characterized by the sudden onset of seizures, headaches, and visual disturbances. Its exact cause is unknown, but several triggers and associated conditions are identified, including high blood pressure, kidney dysfunction, and various medications. Magnetic resonance imaging (MRI) plays a crucial role in diagnosis due to its high sensitivity and specificity for detecting characteristic features. Pediatric PRES exhibit age-dependent differences in triggers, radiological findings, and clinical course. The lesions typically involve the posterior cortical and subcortical white matter, but atypical locations and features are also observed. While generally reversible with appropriate treatment, PRES carries a risk of permanent neurological damage. Despite increasing cases, the current literature on pediatric PRES remains limited. This review highlights the need for further research to understand the mechanisms, delineate distinct clinical and radiological features, and develop precise diagnostic and management strategies for pediatric patients.

Paediatric posterior reversible encephalopathy syndrome: is there an association of blood pressure with imaging severity and atypical magnetic resonance characteristics?

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is relatively uncommon in paediatric patients; however, its pathophysiology remains obscure.

OBJECTIVE

The aims of this study were to find an association or correlation between (1) blood pressures and (2) imaging severity and the presence of atypical imaging features in children with PRES.

MATERIALS AND METHODS

We performed a retrospective cross-sectional evaluation in children diagnosed with PRES. We reviewed radiologic findings along with each patient's clinical profile and outcome. We categorised imaging severity into mild, moderate and severe, and assessed the MR imaging pattern, enhancement and diffusion restriction for each child. We assessed both associations and correlations between variables using the chi-square test, Cramer V and Kendall tau b.

RESULTS

A total of 63 children met the inclusion criteria (31 boys; mean age 9.7 years). A total of 42 children (67%) had an elevated blood pressure. Imaging showed parieto-occipital lobe involvement pattern in 24 (38%) children, frontal lobe pattern in 25 (40%) and cerebellar involvement in 12 (19%). Three (5%) had haemorrhage, 15 (24%) had contrast enhancement and 19 (30%) had positive diffusion restriction (cytotoxic oedema). We found no statistically significant association between imaging severity and blood pressures (P=0.11), nor any association between blood pressure and atypical imaging findings such as diffusion restriction (P=0.1), enhancement (P=0.11) or haemorrhage (P=0.33).

CONCLUSION

According to our results, there is no statistically significant association or correlation between blood pressure and either imaging severity or atypical imaging features in children with PRES. Further prospective studies are warranted.

Clinical features, predictors and outcome of posterior reversible encephalopathy syndrome (PRES) in children with hematolymphoid malignancies

BACKGROUND AND AIM

Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological syndrome characterized by a neurotoxic state with vasogenic edema. We studied the clinical profile, predisposing factors, imaging features, and outcome of PRES in children receiving treatment for hematolymphoid malignancies.

METHODS

Retrospective analysis of the clinical data and radiological features of patients with PRES diagnosed between June 2014 and December 2019.

RESULTS

Fifty-two patients (boy: girl = 3:1) were diagnosed with PRES during the study period with a median age of 11 (range:1-15) years. Primary diagnoses were acute leukemias (n = 42), non-Hodgkin lymphoma (n = 8), Hodgkin lymphoma (n = 1), and Langerhan's cell histiocytosis (n = 1). Most common presenting symptoms were seizures (n = 52), altered sensorium (n = 42), headache (n = 39), and visual disturbances (n = 8). Hypertension at time of diagnosis was noted in 50 (96%) patients. Classic hyper-intense lesions on FLAIR and diffusion weighed (DW) images were noted in parieto-occipital region in 39 patients (75%). Central PRES involving basal ganglia was seen in 3 (6%) patients. A subsequent neuro-imaging was done in 18 patients (MRI: 13; CT: 5) at a median interval of 16.2 weeks. Neurological sequelae were observed in 10 (19%) patients, whereas 1 succumbed due to PRES.

CONCLUSIONS

PRES is an important clinico-radiological syndrome in patients undergoing chemotherapy for hematological malignancies. High index of suspicion, early diffusion-weighted images on MRI in children with classic symptoms help in early diagnosis. A small minority of patients may develop long-term sequelae.