Reversible posterior leukoencephalopathy syndrome: report of 2 simultaneous cases in children

A Review of Acute and Long-Term Neurological Complications Following Haematopoietic Stem Cell Transplant for Paediatric Acute Lymphoblastic Leukaemia

Despite advances in haematopoietic stem cell transplant (HSCT) techniques, the risk of serious side effects and complications still exists. Neurological complications, both acute and long term, are common following HSCT and contribute to significant morbidity and mortality. The aetiology of neurotoxicity includes infections and a wide variety of non-infectious causes such as drug toxicities, metabolic abnormalities, irradiation, vascular and immunologic events and the leukaemia itself. The majority of the literature on this subject is focussed on adults. The impact of the combination of neurotoxic drugs given before and during HSCT, radiotherapy and neurological complications on the developing and vulnerable paediatric and adolescent brain remains unclear. Moreover, the age-related sensitivity of the nervous system to toxic insults is still being investigated. In this article, we review current evidence regarding neurotoxicity following HSCT for acute lymphoblastic leukaemia in childhood. We focus on acute and long-term impacts. Understanding the aetiology and long-term sequelae of neurological complications in children is particularly important in the current era of immunotherapy for acute lymphoblastic leukaemia (such as chimeric antigen receptor T cells and bi-specific T-cell engager antibodies), which have well-known and common neurological side effects and may represent a future treatment modality for at least a fraction of HSCT-recipients.

Etiologies, Cerebral Vasomotion, and Endothelial Dysfunction in the Pathophysiology of Posterior Reversible Encephalopathy Syndrome in Pediatric Patients

The posterior reversible encephalopathy syndrome was characterized by Hinchey and colleagues in the 1990s. The condition frequently afflicts patients suffering from hematologic and solid organ malignancy and individuals undergoing transplantation. Cases are more frequently described in the adult population compared with children. In the pediatric population, malignancy, transplantation, renal disease, and hypertension represent the most common etiologies. Theories on pathogenesis have centered upon cerebrovascular dysautoregulation with increases in blood–brain barrier permeability. This generates vasogenic edema of the cerebral parenchyma and consequent neurologic deficits. The parietal and occipital lobes are affected with greatest prevalence, though frontal and temporal lobe involvement is frequent, and that of the contents of the infratentorial posterior cranial fossa are occasionally described. The clinical presentation involves a characteristic constellation of neurologic signs and symptoms, most typically inclusive of headache, visual-field disturbances, abnormalities of visual acuity, and seizures. Supportive care, withdrawal of the offending agent, antihypertensive therapy, and prophylactic anticonvulsants affect convalescence in majority of cases. The principal challenge lies in identifying the responsible agent precipitating the condition in patients with malignancy and those having undergone transplantation and thus deciding which medication among a multidrug treatment regimen to withhold, the duration of drug cessation required to effect clinical resolution, and the safety of resuming treatment with the compound. We accordingly reviewed and evaluated the literature discussing the posterior reversible encephalopathy syndrome in children.

Posterior reversible encephalopathy syndrome in pediatric patients: pathophysiology, diagnosis, and management

Posterior reversible encephalopathy syndrome (PRES) is well-described in adults, but has been reported with relative rarity in children, usually occurring in the context of chemotherapy for acute leukemia. Pathogenesis involves perturbed cerebral autoregulation leading to vasogenic edema predominantly affecting the parieto-occipital white matter, though involvement of the frontal and temporal lobes, as well as posterior fossa, is also described. We review the literature on the pathophysiology, diagnosis, and management of PRES in pediatric patients.

PRES in the course of hemato-oncological treatment in children

INTRODUCTION

Posterior reversible leukoencephalopathy syndrome (PRES) is a clinical syndrome of varying aetiologies, characterised by acute neurological symptoms of brain dysfunction with MRI abnormalities in posterior cerebral white and grey matter. In most cases, symptoms resolve without neurological consequences.

AIM

The aim of this paper is the analysis of predisposing factors, clinical outcomes and radiological features of PRES in eight children with hemato-oncological disease.

MATERIAL AND METHODS

We analysed the medical records of eight hemato-oncological patients aged from 3.0 to 16.1 years. The mean of age at primary diagnosis was 8.5 years.

RESULTS

All patients had both clinical and radiological PRES features. Seven out of eight underwent intensive chemotherapy regimens. Time elapsed from start of treatment to the occurrence of PRES ranged from 6 to 556 days. In one case, PRES occurred before chemotherapy and was the first symptom of cancer. Most (six of eight) patients had history of hypertension (> 95pc) and some (two of eight) occurred electrolyte imbalance-mainly hypomagnesaemia. Patients presented headache (seven of eight), disturbances of consciousness (six of eight), seizures (six of eight), visual changes (four of eight) and vomiting (three of eight). MRI demonstrated abnormalities in seven children: typical cerebral oedema in the white matter of the occipital to the parietal lobes. Most patient lesions in the MRI shrunk after 4 weeks, and clinical symptoms of PRES disappeared completely within a few hours to few days.

CONCLUSION

PRES may complicate oncological treatment in children. Hypertension is the most important risk factor of PRES. PRES should be included in differential diagnosis in all patients with acute neurological symptoms.

Hepatoblastoma in an 11-year-old: Case report and a review of the literature

RATIONALE

Hepatoblastoma is a rare malignancy. Approximately 100 cases are diagnosed yearly in the United States. The highest incidence occurs in infants and in children younger than 5 years. Cases involving patients older than 5 years are very rare. We describe the case of a patient who was diagnosed with hepatoblastoma at an atypical age of presentation for this type of malignancy. We also performed Ovid MEDLINE search for hepatoblastoma and epidemiology reports occurring in children between the ages of 5 and 18 years. In this article we review the epidemiology and summarize case reports published between 1997 and 2012 of patients with hepatoblastoma, who were older than 5 years.

PATIENT CONCERNS AND DIAGNOSIS

Our patient is an 11 year old boy with stage IV hepatoblastoma with lung and omental metastases at diagnosis.

INTERVENTIONS

The patient received 7 cycles of chemotherapy following the treatment plan of COG protocol AHEP 0731, off study. He also had tumor resection and omentectomy and achieved complete remission.

OUTCOMES

He later had disease recurrence and after undergoing treatment with different modalities, ultimately died of his disease. Review of SEER program data shows that the incidence of hepatoblastoma in children above the age of 5 years is too infrequent to be calculated. Literature review revealed 13 cases of patients diagnosed at age older than 5 years. Most cases were published due to unusual associations and/or complications. There are no obvious unifying characteristics for these cases, although there may be a slight male preponderance and many patients in this selected series presented with elevated Alpha-fetoprotein.

LESSONS

The reported case is rare, given the very low incidence of hepatoblastoma outside of infancy. A systematic review of characteristics and outcomes for patients older than 5 years who are enrolled in cooperative group hepatoblastoma trials may reveal important information about the epidemiology and tumor biology in this rare patient population.

Prognostic factors in children with PRES and hematologic diseases

OBJECTIVES

Posterior reversible encephalopathy syndrome (PRES) is a clinical and radiological entity characterized by focal neurological signs, headache, confusion, and seizure, associated with transitory lesions in the posterior areas of the brain detectable with neuroimaging. Among children, one of the most common causes of PRES is cancer.

MATERIALS AND METHODS

In this review, we present the cases of 5 children developing PRES after stem cell transplantation for hematological disease and review all the cases reported in English literature to investigate outcomes and associated risk factors.

RESULTS

One hundred and eleven cases were reported. Hypertension was very frequent (80%). Clinical features included seizures (80.1%), headache (44.1%), visual disturbance (26.1%), and mental change (48.6%). EEG was abnormal in 27 of 32 patients. MRI revealed characteristic lesions in all patients even in early stages. Abnormal MRI findings in late stages were associated with neurological sequelae. Nineteen patients died (17.1%) of which 2 of PRES. Among alive patients, 17 had neurological sequelae. Four cases of PRES relapse were described.

CONCLUSIONS

Thus, all transplant recipients with symptoms consistent with PRES should be promptly recognized to avoid long-term complications or even death.

Asparaginase-associated toxicity in children with acute lymphoblastic leukemia

Asparaginase is an integral component of multiagent chemotherapy regimens for the treatment of children with acute lymphoblastic leukemia. Positive outcomes are seen in patients who are able to complete their entire prescribed course of asparaginase therapy. Toxicities associated with asparaginase use include hypersensitivity (clinical and subclinical), pancreatitis, thrombosis, encephalopathy, and liver dysfunction. Depending on the nature and severity of the toxicity, asparaginase therapy may be altered or discontinued in some patients. Clinical hypersensitivity is the most common asparaginase-associated toxicity requiring treatment discontinuation, occurring in up to 30% of patients receiving Escherichia coli-derived asparaginase. The ability to rapidly identify and manage asparaginase-associated toxicity will help ensure patients receive the maximal benefit from asparaginase therapy. This review will provide an overview of the common toxicities associated with asparaginase use and recommendations for treatment management.

Predisposing factors of posterior reversible encephalopathy syndrome in acute childhood leukemia

A retrospective chart review was performed on 19 patients aged <18 years who developed posterior reversible encephalopathy syndrome as a complication during treatment of acute childhood leukemia. Posterior reversible encephalopathy syndrome was most often observed during acute lymphoblastic leukemia induction chemotherapy (n = 9, 47.4%) and after hematopoietic stem cell transplantation (n = 8, 42.1%). Among eight patients with the complication of posterior reversible encephalopathy syndrome after hematopoietic stem cell transplantation, five (62.5%) had a history of hypertension. In contrast, among 11 patients with the complication of posterior reversible encephalopathy syndrome without hematopoietic stem cell transplantation, only one (9.1%) had a history of hypertension. Moreover, unlike other leukemia induction chemotherapy, posterior reversible encephalopathy syndrome developed only in patients who received acute lymphoblastic leukemia induction chemotherapy. Posterior reversible encephalopathy syndrome patients required long-term anticonvulsant therapy (n = 9, 50.0%) and manifested intractable seizures (n = 3, 16.7%). Sequelae were evident in long-term follow-up magnetic resonance images (n = 5, 26.3%). Acute lymphoblastic leukemia chemotherapy regimens apparently comprised the main predisposing factors for posterior reversible encephalopathy syndrome complicated during induction chemotherapy, compared with hypertension and immunosuppressive agents after hematopoietic stem cell transplantation.

Posterior reversible encephalopathy syndrome in paediatric leukaemia

This report describes four patients with acute lymphoblastic leukaemia, suffering from posterior reversible encephalopathy syndrome during the induction period of treatment. A review of the literature on posterior reversible encephalopathy syndrome in paediatric leukaemia is given. The exact mechanism of posterior reversible encephalopathy syndrome is not clear and seems to be multifactorial. Hypertension is likely to play a major role in the development but could be also secondary. All patients in this case series presented after introduction of the new induction protocol for acute lymphoblastic leukaemia. Treatment of hypertension is likely to have a favourable role and posterior reversible encephalopathy syndrome is most often reversible. It is important to consider this diagnosis during the induction phase of leukaemia treatment in the presence of neurological symptoms. The incidence of PRES in the induction scheme should be investigated, in order to optimize the ALL treatment.

Central nervous system complications during treatment of acute lymphoblastic leukemia in a single pediatric institution

Central nervous system (CNS) complications during treatment of childhood acute lymphoblastic leukemia (ALL) remain a challenging clinical problem. Outcome improvement with more intensive chemotherapy has significantly increased the incidence and severity of adverse events. This study analyzed the incidence of neurological complications during ALL treatment in a single pediatric institution, focusing on clinical, radiological, and electrophysiological findings. Exclusion criteria included CNS leukemic infiltration at diagnosis, therapy-related peripheral neuropathy, late-onset encephalopathy, or long-term neurocognitive defects. During a 9-year period, we retrospectively collected 27 neurological events (11%) in as many patients, from 253 children enrolled in the ALL front-line protocol. CNS complications included posterior reversible leukoencephalopathy syndrome (n = 10), stroke (n = 5), temporal lobe epilepsy (n = 2), high-dose methotrexate toxicity (n = 2), syndrome of inappropriate antidiuretic hormone secretion (n = 1), and other unclassified events (n = 7). In conclusion, CNS complications are frequent events during ALL therapy, and require rapid detection and prompt treatment to limit permanent damage.

Posterior reversible encephalopathy syndrome in childhood cancer

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) is characterized by seizures, headaches, altered mental status, cortical blindness and typical transient lesions on magnetic resonance imaging.

PATIENTS AND METHODS

We describe seven childhood cancer patients with clinical and radiological symptoms of PRES, and reviewed all well-documented PRES cases reported during childhood cancer treatment.

RESULTS

Fifty-six children with PRES, including our 7 cases, were identified in the literature. Mean age at onset was 9 (range: 2-17) years. Primary diagnoses were acute lymphoblastic leukemia (n = 31), acute myeloid leukemia (n = 5), non-Hodgkin lymphoma (n = 7) and solid tumors (n = 13). PRES patients presented with seizures (n = 50), altered mental status (n = 20), visual disturbances (n = 24) and/or headaches (n = 17). PRES was associated with hypertension in 49 patients. About 86% of the patients had both clinical and radiological reversible symptoms. Four patients developed epilepsy, in one patient ataxia remained and one patient had a persistent mydriasis.

CONCLUSION

Although PRES has predominantly been described in leukemia patients, it occurs in children with solid tumors as well. Hypertension seems to be the most important trigger for the occurrence of PRES during childhood cancer treatment. Seizures are the most common accompanying sign. Symptoms and radiological findings normalize in ∼90% of the cases, but in 10% neurological symptoms remain.

Simultaneous occurrence of posterior reversible leukoencephalopathy syndrome in two cases of childhood acute lymphoblastic leukemia induction chemotherapy

We describe two cases Posterior Reversible Encephalopathy Syndrome (PRES) occurring in childhood B-precursor acute lymphoblastic leukemia within a week of each other during induction chemotherapy in our ward. We review the literature related to the possible etiology of PRES in these cases.

Brain Magnetic Resonance Imaging After High-Dose Chemotherapy and Radiotherapy for Childhood Brain Tumors

PURPOSE

Brain necrosis or other subacute iatrogenic reactions has been recognized as a potential complication of radiotherapy (RT), although the possible synergistic effects of high-dose chemotherapy and RT might have been underestimated.

METHODS AND MATERIALS

We reviewed the clinical and radiologic data of 49 consecutive children with malignant brain tumors treated with high-dose thiotepa and autologous hematopoietic stem cell rescue, preceded or followed by RT. The patients were assessed for neurocognitive tests to identify any correlation with magnetic resonance imaging (MRI) anomalies.

RESULTS

Of the 49 children, 18 (6 of 25 with high-grade gliomas and 12 of 24 with primitive neuroectodermal tumors) had abnormal brain MRI findings occurring a median of 8 months (range, 2-39 months) after RT and beginning to regress a median of 13 months (range, 2-26 months) after onset. The most common lesion pattern involved multiple pseudonodular, millimeter-size, T1-weighted unevenly enhancing, and T2-weighted hyperintense foci. Four patients with primitive neuroectodermal tumors also had subdural fluid leaks, with meningeal enhancement over the effusion. One-half of the patients had symptoms relating to the new radiographic findings. The MRI lesion-free survival rate was 74%+/-6% at 1 year and 57%+/-8% at 2 years. The number of marrow ablative courses correlated significantly to the incidence of radiographic anomalies. No significant difference was found in intelligent quotient scores between children with and without radiographic changes.

CONCLUSION

Multiple enhancing cerebral lesions were frequently seen on MRI scans soon after high-dose chemotherapy and RT. Such findings pose a major diagnostic challenge in terms of their differential diagnosis vis-à-vis recurrent tumor. Their correlation with neurocognitive results deserves further investigation.