Reversible Splenial Lesion Syndrome (RESLES): What's in a Name?

Predictive factors of de novo epilepsy in reversible splenial lesion syndrome

PURPOSE

Reversible splenial lesion syndrome (RESLES) is a rare neurological disorder in East Asia with good prognosis. Herein, we investigated the predictive factors for de novo epilepsy in RESLES.

METHOD

This single-centre cohort study was conducted at Sendai Medical Center in Japan, enrolling patients with RESLES without previous epilepsy treated between February 2008 and May 2023 with follow-up for at least 1 month. The outcome was de novo epilepsy during or after RESLES without other aetiologies of epilepsy. The variables during RESLES admission were compared between patients with (Group A) and without (Group B) de novo epilepsy. Statistical analyses were performed using the Mann-Whitney U or Fisher's exact tests.

RESULT

Twenty-two patients (males 11/22; 50 %) met the inclusion criteria. The mean age and median follow-up duration were 37 ± 20 years and 35.9 months (range: 2.4 to 199 months), respectively. The aetiologies included infection (10/22, 45.5 %), cerebrovascular disorders (3/22, 13.6 %), and others (8/22, 36.4 %). Acute symptoms included fever (14/22, 63.6 %), altered mental status (19/22, 86.4 %), seizures (8/22, 36.4 %), and status epilepticus (2/22, 9.1 %). MRI showed splenial lesions (mean vertical length 7.0 ± 1.7 mm and mean horizontal length 14.2 ± 7.6 mm) and extra splenium lesions of corpus callosum (1/22; 4.5 %). 9.1 % (2/22) developed de-novo epilepsy. Status epilepticus (2 vs 0; p = 0.001), long horizontal splenial lesions (24.7 mm vs 13.2 mm; p = 0.04), use of anti-seizure medication (3 vs 2; p = 0.04) were significantly more common in Group A than B.

CONCLUSION

Status epilepticus during the acute phase of RESLES may predict the development of epilepsy.

Pediatric anti-CaVα2δ autoimmune encephalitis: A case report and literature review

Anti-voltage-gated calcium channel alpha-2/delta subunit (anti-CaVα2δ) encephalitis is a rare autoimmune encephalitis (AE), with only two cases of anti-CaVα2δ AE have been reported in the literatureto date. The clinical characteristics and prognosis of this rare AE need to beexpanded.We present the case of a 9-year-oldgirl, who initially presented with fever and lymphadenitis, which progressed to headaches, drowsiness, frequent seizures, cognitive impairment, memory loss, and involuntary movements. Brain magnetic resonance imaging revealed lesions in the bilateral external capsule. Moreover, anti-CaVα2δ antibodies were detected (1,30) 3 and 5 weeks after symptom onset. Video electroencephalography revealed slow, severely diffuse, background activity with multifocal epileptiform discharges. Although the patient was administered a combined immunotherapy consisting of intravenous immunoglobulin, intravenous methylprednisolone, and rituximab, sheexhibited persistent neurological sequelae at the last follow-up (Modified Rankin Scale score of 4; Pediatric Quality of Life Inventory score of 75). Whileour case shares similar clinical characteristics with previously reported anti-CaVα2δ AE cases, our patientwas unresponsive to immunotherapy and experienced severe neurological sequelae during follow-up. This report broadens the clinical phenotype and prognosis associated with this rare condition, providing further information and clinical insights for the management of future cases.

Tuberculous Meningitis in a Child: A Rare Presentation of Cytotoxic Lesion of the Corpus Callosum

Tuberculous meningitis (TBM) is the most severe form of tuberculosis, disproportionately affecting vulnerable populations such as young children and people living with human immunodeficiency virus (HIV). Major challenges to accurate and early diagnosis of TBM are the non-specific clinical features which overlap with other infectious syndromes and the lack of adequately sensitive tests to detect Mycobacterium tuberculosis in the cerebrospinal fluid (CSF). Diagnosis is, therefore, still dependent on clinical suspicion along with clinical features, cerebrospinal fluid (CSF) characteristics and, where facilities are available, neuroimaging. Typical neuroimaging features of TBM include hydrocephalus, infarcts, tuberculomas and basal exudates; however, less well described are very rare features such as cytotoxic lesion of the corpus callosum (CLOCC), otherwise known as transient splenic lesion. We describe the first case report of a child with confirmed TBM who had a very rare presentation of CLOCC with complete recovery and present a literature review on the pathophysiology and alternative aetiologies where CLOCC is more commonly seen.

Case report: Re-evaluating reversibility of cytotoxic lesions of the corpus callosum

Cytotoxic lesions of the corpus callosum (CLOCC) are a clinicoradiological diagnosis, characterized by transient neurological symptoms and magnetic resonance imaging (MRI) changes in the splenium of the corpus callosum (SCC), which in most cases is completely reversible. However, the long-term pathophysiological trajectory and ultimate neurological outcomes of CLOCC remain largely unknown due to limited long-term follow-up data. We report an 11-year follow-up of a postpartum female with CLOCC, initially presenting with transient focal neurological symptoms and extensive diffusion-restricted white matter involvement including the SCC and surrounding area with diffusion restriction and low apparent diffusion coefficient values, indicative of cytotoxic edema. The edema regressed in days; over the years, she remained asymptomatic despite persistent white matter changes on MRI in the centrum semiovale. This case challenges the view of CLOCC as completely reversible and raises questions regarding the significance of lasting white matter changes. The enduring absence of neurological symptoms and stable radiological profile throughout the decade underscores the singular nature of CLOCC and the lasting, though isolated, impact on white matter. This report contributes a crucial perspective, suggesting that CLOCC may involve just an isolated episode without recurrent events or progressive neurological decline. By offering the first longitudinal analysis of a CLOCC episode with an extended follow-up of over a decade, our case enhances current knowledge about the long-term neurological and radiological landscape of this condition. It suggests a reevaluation of the conceptual understanding of CLOCC as an entirely reversible, non-relapsing disorder, highlighting the need for further research into its long-term impacts on cerebral white matter integrity.

Case report: Reversible splenial lesion syndrome preceding the onset of multiple sclerosis

Background

The reversible splenial lesion syndrome is frequently associated with systemic and central nervous system infections. Whether an infection associated with the occurrence of the reversible splenial lesion syndrome could play a role in the later development of multiple sclerosis is unknown.

Methods

Case Report.

Results

A 27-year-old woman developed an infection-related reversible splenial lesion syndrome. Diagnostic findings did not establish a specific type of infection, but revealed evidence for a potential disposition towards autoimmunity. 32 months after the initial presentation, new clinical and radiological manifestations developed that led to a diagnosis of multiple sclerosis.

Conclusions

In susceptible individuals, infectious disease processes involving the central nervous system, such as described in this case, might be a factor in the pathogenesis of multiple sclerosis. More research on the prodromal stage of multiple sclerosis is needed to better understand the relationship between infections and autoimmunity.

Altitude-related features and prognosis in patients with reversible splenial lesion syndrome

INTRODUCTION

RESLES (Reversible splenial lesion syndrome) can be observed secondary to various diseases, and intramyelinic edema may play a crucial role in the pathogenesis of SCC (Splenium of the corpus callosum). Some studies have suggested that hypoxic-ischaemic encephalopathy may constitute a risk factor for SCC lesions. However, the potential impact of high-altitude environments on SCC, especially during chronic exposure, remain obscure.

METHODS

Our study included 19 patients who satisfied the diagnostic criteria of RESLES at high altitudes. Ten low-altitude patients with RESLES were included as controls. All participants received MRI (Magnetic resonance imaging) scans twice. Routine blood tests, liver, kidney and thyroid function, coagulation function, electrolytes and vitamins were detected during hospitalization and before discharge. In addition, the patients were followed up in May 2023.

RESULTS

Hypoxic environments at high altitudes may increase the risk of RESLES. The two groups showed different clinical symptoms. High-altitude patients had significantly higher CRP levels than low-altitude patients. The lesion size in high-altitude patients showed a positive correlation with SaO2 levels. However, the patients at low altitudes had positive correlation trends between lesion size and several inflammatory markers (WBC, NEU and CRP). All patients had a benign prognosis that may not be affected by the use of prednisone acetate.

CONCLUSIONS

Hypoxic environments at high altitudes may play a role in the aetiology of RESLES. Additionally, RESLES is a reversible disease and the administration of glucocorticoids may be dispensable for its treatment.

Adult-onset of mild encephalitis/encephalopathy with reversible splenial lesion (MERS): case report and systematic review

BACKGROUND

Mild encephalitis/encephalopathy with reversible splenial lesion (MERS) is a clinical-radiological syndrome characterized by transient central nervous system symptoms and a reversible lesion in the splenium of the corpus callosum (SCC) on magnetic resonance (MR). We reported a case of adult-onset MERS with uncommon presentation and reviewed the existing literature.

METHODS

We described a case of adult-onset MERS with uncommon symptoms and signs and performed a systematic review of case series including more than four patients of adult-onset (> 14 years old) MERS, from January 2000 to December 2022. We summarized the clinical, laboratory, imaging and therapy data.

RESULTS

We included seven eligible studies for a total of 51 adult-onset MERS patients. Neurological manifestations were preceded by prodromal symptoms in most of the patients (88%), mainly with fever (78%). Headache was the most common symptom (50%), followed by seizures (22%) and disturbance of consciousness (22%). Inflammatory changes on cerebrospinal fluid were present in a half of patient, so defining encephalitis cases. Clinal recovery, was achieved in all patients but two with severe disturbance of consciousness who required ventilator support in the acute phase. MR showed isolated lesion in the SCC in 92% of patients, while 8% of patients showed also extracallosal lesions, all the lesions resolved or improved on follow-up imaging.

CONCLUSIONS

MERS is a form of encephalitis/encephalopathy with a broad range of central nervous system manifestation, often with mild symptoms, such as headache alone, that can lead to overlooked some cases, with an excellent prognosis in most patient.

Mild Encephalopathy/Encephalitis with Reversible Splenial Lesions after Amphetamine and Opioid Use

A 47-year-old woman with a history of substance abuse, depression, and insomnia experienced a collapse. Upon arrival at the hospital, the patient displayed low systolic blood pressure, confusion, dehydration, and renal failure. Urine tests confirmed an amphetamine and opioid overdose. Her condition fluctuated with reduced consciousness, myoclonic movements, fever, and suspected psychogenic seizures. Brain magnetic resonance imaging revealed abnormalities in the splenium of the corpus callosum, which later resolved. The patient's condition gradually improved without any specific treatment. This unique case represents the first report of mild encephalopathy/encephalitis with reversible splenial lesions associated with amphetamine and opioid use.

Febrile neutropenia induced by adjuvant radiotherapy for a patient with breast cancer accompanied with reversible splenial lesion syndrome (RESLES, TypeI): a case report

BACKGROUND

Reversible splenial lesion syndrome (RESLES) is known as a neuro-imaging syndrome with recurrent but reversible lesion of the corpus callosum, characterized by nonspecific but usually mild encephalopathies and specific imaging manifestations.There are few published reports in the field of oncology.

CASE PRESENTATION

A 33-year-old female with right breast cancer and with no particular family history was admitted to hospital with high fever and severe headache, after receiving adjuvant radiotherapy. Blood routine test upon admission suggested neutropenia, considering myelosuppression associated with radiotherapy. There were no definite findings of common pathogenic microorganism, and no imaging indication of certain infectious sites other than a likely reversible corpus callosum syndrome suggested by brain MRI, which was relieved after systemic antibiotic therapy and granulocyte colony-stimulating factor injection.

CONCLUSIONS

Reversible splenial lesion syndrome is a kind of clinical-imaging syndrome with multiple clinical manifestations and etiologies. This breast cancer patient after postoperative adjuvant radiotherapy develops a complication of RESLES that rings an alarm bell to the oncologists not to easily recognize the corpus callosum lesion as infarction or metastasis. Meanwhile, the potential pathogenic mechanisms need to be explored further.

Cytotoxic lesions of the corpus callosum: a systematic review

OBJECTIVES

Cytotoxic lesions of the corpus callosum (CLOCC) are a common magnetic resonance imaging (MRI) finding associated with various systemic diseases including COVID-19. Although an increasing number of such cases is reported in the literature, there is a lack of systematic evidence summarizing the etiology and neuroimaging findings of these lesions. Thus, the aim of this systematic review was to synthesize the applied nomenclature, neuroimaging and clinical features, and differential diagnoses as well as associated disease entities of CLOCC.

MATERIALS AND METHODS

A comprehensive literature search in three biomedical databases identified 441 references, out of which 324 were eligible for a narrative summary including a total of 1353 patients.

RESULTS

Our PRISMA-conform systematic review identifies a broad panel of disease entities which are associated with CLOCC, among them toxic/drug-treatment-associated, infectious (viral, bacterial), vascular, metabolic, traumatic, and neoplastic entities in both adult and pediatric individuals. On MRI, CLOCC show typical high T2 signal, low T1 signal, restricted diffusion, and lack of contrast enhancement. The majority of the lesions were reversible within the follow-up period (median follow-up 3 weeks). Interestingly, even though CLOCC were mostly associated with symptoms of the underlying disease, in exceptional cases, CLOCC were associated with callosal neurological symptoms. Of note, employed nomenclature for CLOCC was highly inconsistent.

CONCLUSIONS

Our study provides high-level evidence for clinical and imaging features of CLOCC as well as associated disease entities.

CLINICAL RELEVANCE STATEMENT

Our study provides high-level evidence on MRI features of CLOCC as well as a comprehensive list of disease entities potentially associated with CLOCC. Together, this will facilitate rigorous diagnostic workup of suspected CLOCC cases.

KEY POINTS

• Cytotoxic lesions of the corpus callosum (CLOCC) are a frequent MRI feature associated with various systemic diseases. • Cytotoxic lesions of the corpus callosum show a highly homogenous MRI presentation and temporal dynamics. • This comprehensive overview will benefit (neuro)radiologists during diagnostic workup.

Brain magnetic resonance imaging findings in children with neurological complications of coronavirus disease 2019 (Omicron variant): a multicenter retrospective observational study

BACKGROUND

An increasing rate of encephalopathy associated with coronavirus disease 2019 (COVID-19) has been observed among children. However, the literature on neuroimaging data in children with COVID-19 is limited.

OBJECTIVE

To analyze brain magnetic resonance imaging (MRI) of pediatric COVID-19 patients with neurological complications.

MATERIALS AND METHODS

This multicenter retrospective observational study analyzed clinical (n=102, 100%) and neuroimaging (n=93, 91.2%) data of 102 children with COVID-19 infections and comorbid acute neurological symptoms. These children were hospitalized at five pediatric intensive care units (PICUs) in China between December 1, 2022, and January 31, 2023.

RESULTS

All patients were positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as detected via reverse transcriptase polymerase chain reaction. About 75.7% of the children were infected with the Omicron variant BF.7 strain. Brain MRI was performed 1-12 days following the onset of neurological symptoms, which revealed acute neuroimaging findings in 74.2% (69/93) of cases, including evidence of acute necrotizing encephalopathy (33/69, 47.8%), encephalitis (31/69, 44.9%), reversible splenial lesion syndrome (3/69, 4.3%), reversible posterior leukoencephalopathy (1/69, 1.4%), and hippocampal atrophy (1/69, 1.4%).

CONCLUSIONS

Overall, these data highlighted five neuroimaging patterns associated with the outbreak of the SARS-CoV-2 Omicron variant, with acute necrotizing encephalopathy being the most common of these neuroimaging findings. Rarely, the brain MRI of these pediatric COVID-19 patients also demonstrate hippocampal atrophy.

Transient blindness due to mild reversible encephalopathy in a 7-year-old boy

Mild encephalopathy with a reversible splenial lesion (MERS) is a rare phenomenon, which shows transient lesion in corpus callosum and causes temporary encephalopathy features. A disturbance of consciousness and abnormal and delirious behavior are the most significant neurological symptoms. A seven-year-old child with a history of fever and cough was admitted to our hospital due to sudden bilateral blindness. His physical examination showed confusion, fever, and delirious behavior. No sign of meningeal irritation or focal neurological deficit was observed. The electroencephalogram showed diffuse slow waves representing mild encephalopathy. Brain MRI showed a signal alteration in the splenium of the corpus callosum, and magnetic resonance angiography (MRA) was normal. This finding was suggestive of a reversible cytotoxic lesion. Treatment with empiric antivirals was initiated, and the symptoms were completely resolved. In a few children, sudden blindness has been reported to be an initial symptom of MERS. There is currently no evidence of efficient treatment methods. However, to convince patients and their families about the good outcome of the disease, the diagnosis of MERS provides pediatricians with useful prognostic information.

Reversible splenial lesion syndrome in patient with acute motor and sensory axonal neuropathy

Even though the classical clinical concept supports the clear difference between diseases affecting the central and peripheral nervous systems, this difference is becoming less rigid. Here, we report the case of a 50-year-old male patient who presented with acroparaesthesia, headache, and flaccid tetraparesis after febrile diarrhea. Nerve conduction studies indicated action potentials with low amplitudes, which are typical in acute motor and sensory axonal neuropathy. Magnetic resonance revealed a round lesion in the splenium consistent with a diagnosis of reversible splenial lesion syndrome. A polyclonal antiganglioside antibody response was detected. The patient was successfully treated with intravenous immunoglobulins. The coexistence of reversible splenial lesion syndrome and acute motor and sensory axonal neuropathy has not been described in the literature so far. We discuss our diagnostic dilemmas and the possible role of antiganglioside antibodies in the occurrence of simultaneous lesions of the central and peripheral nervous systems.

Cytotoxic lesions of the corpus callosum (CLOCCs) with a flow gap in straight sinus on magnetic resonance venography

Cytotoxic lesions of the corpus callosum (CLOCCs) are cytotoxic lesions observed in the splenium of the corpus callosum and are also called mild encephalitis or encephalopathy with reversible splenial lesions or reversible splenial lesion syndrome. It was first reported in patients with epilepsy and since then has been observed in a wide variety of diseases, including infections, trauma, metabolic disorders (hyperglycaemia, hypernatraemia and hyponatraemia), mountain sickness and cerebral venous sinus thrombosis. Here, we present a patient with CLOCCs accompanied by a flow gap in the straight sinus on magnetic resonance venography without any evidence of cerebral venous sinus thrombosis and discuss the possible clinical implications.

Case report: Clinically mild encephalitis/encephalopathy with a reversible splenial lesion: an autopsy case

Clinically mild encephalitis/encephalopathy with a reversible splenial lesion is a clinicoradiological syndrome characterized by transient neuropsychiatric symptoms and hyperintensity of the splenium of the corpus callosum on diffusion-weighted MRI. Although intramyelinic edema and inflammatory cell infiltration can be predicted by MRI, the pathology of the splenium of the corpus callosum remains unknown. We encountered a case of clinically mild encephalitis/encephalopathy with a reversible splenial lesion and hypoglycemia in a patient who died of sepsis, and an autopsy was performed. The postmortem pathological findings included intramyelinic edema, myelin pallor, loss of fibrous astrocytes, microglial reactions, and minimal lymphocytic infiltration in the parenchyma. Based on these findings, transient demyelination following cytotoxic edema in the splenium of corpus callosum was strongly considered a pathogenesis of "clinically mild encephalitis/encephalopathy with a reversible splenial lesion" associated with hypoglycemia, and it could be generalized for the disease associated with the other causes. As cytotoxic edema could be the central pathology of the disease, the recently proposed term cytotoxic lesions of the corpus callosum may be applicable to this syndrome.

Acute alcohol intoxication presenting acquired lesion of the corpus callosum in a young healthy woman: A case of possible Marchiafava-Bignami disease

Background

Marchiafava-Bignami disease is a rare neurological disease characterized by acquired lesions of the corpus callosum. Although the major causative etiology is chronic alcoholism, a case caused by acute alcohol intoxication has not yet been reported.

Case Presentation

A 19-year-old female with no known medical history or a history of chronic alcohol consumption was brought to the emergency department in a coma after binge alcohol consumption. Even after an overnight observation, she remained comatose. After a thorough examination including magnetic resonance imaging, which showed lesions of the corpus callosum, she was treated with thiamine for Marchiafava-Bignami disease. She recovered completely and at the follow-up, the callosum lesion had resolved.

Conclusion

This is a rare case within the spectrum of Marchiafava-Bignami disease caused by acute consumption of alcohol. Clinicians should be aware of this potentially devastating critical condition among patients with severe alcohol intoxication, which might have been overlooked.

West Nile virus encephalomyelitis in an immunocompromised patient

We report a case of a 50-year-old immunocompromised woman who presented with acute encephalopathy and gait ataxia due to severe West Nile virus encephalomyelitis. The patient remarkably improved following early and sustained aggressive immunomodulation. Diagnosing West Nile neuroinvasive disease could be challenging without biochemical evidence of West Nile virus nucleic acid in the cerebrospinal fluid, a specific but not sensitive test. Although the neuroimaging findings in our patient could be considered "typical" for West Nile neuroinvasive disease, there is an overlap with the imaging abnormalities seen in other neuroinflammatory disorders presenting with acute leukoencephalopathy. Hence, we review West Nile neuroinvasive disease imaging characteristics and the differential diagnosis of acute leukoencephalopathy.

Clinico-radiologic subtypes and therapeutic observation of acute Marchiafava-Bignami disease

We aimed to investigate the clinico-radiologic features of acute Marchiafava-Bignami disease (MBD) and its evolutionary process after effective treatment through subgroup comparison. The clinical and MRI data of 23 patients with acute MBD were retrospectively analyzed and divided into type A (12 cases, with entire callosal involvement) and type B (11 cases, with focal callosal involvement). The clinical assessments and MRI findings (before and after treatment) were compared between the two subtypes. Compared with type B, type A had lower MoCA (Montreal Cognitive Assessment) scores at admission (16.50 ± 1.73 vs 18.27 ± 1.68, P = 0.021) and were more common with extracallosal involvement (66.67% vs 18.18%, P = 0.036) and longer illness duration (18.3 ± 2.1 days vs 15.6 ± 2.4 days, P = 0.012). During the treatment, the residual lesion in the splenium was more common in type A (58.33% vs 9.09%, P = 0.027). After treatment, the MoCa scores of both subtypes gradually increased (P < 0.001), and the callosal and extracallasal lesions disappeared completely. Clinico-radiologic typing of acute MBD is related to the severity of early symptoms, but not to the prognosis. Complete clinico-radiologic recovery is possible for both subtypes with combined treatment. The clinico-radiologic reversibility is helpful for accurate diagnosis and therapeutic evaluation.

Diffusion-Restricted Lesions of the Splenium: Clinical Presentation, Radiographic Patterns, and Patient Outcomes

Background and Objectives

Diffusion-restricted (DR) lesions of the splenium are encountered in a wide variety of pathologies, and their significance is often unclear. We sought to report the spectrum of clinical presentations, neuroimaging patterns, and the predictors of radiographic and clinical outcomes from DR splenial lesions.

Methods

This was a single-center, retrospective cohort study from January 1, 2009, to August 1, 2020. A consecutive sample of 3,490 individuals who underwent brain MRI with reported corpus callosum lesions during the study period were evaluated for DR lesions in the corpus callosum. DR lesions were defined as increased signal intensity on diffusion-weighted imaging sequences with decreased signal intensity on apparent diffusion coefficient. Patients with prior neurosurgical procedures, hemorrhage-associated DR, anoxic brain injury, and chronic or previously known or characterized disease processes in the corpus callosum were excluded. Clinical and radiologic outcomes were ascertained, including readmissions within 1 year, in-hospital mortality rates, and resolution of DR at first follow-up imaging. Outcomes were defined a priori.

Results

Two hundred patients met criteria for inclusion. The average age was 57 years (standard deviation 19 years). Near half of the patients were women (47%). Encephalopathy (55%), focal weakness (46.5%), and cortical signs (44%) were the most common presenting clinical features. Thirty-five cases (17.5%) had features consistent with cytotoxic lesions of the corpus callosum (CLOCCs). Vascular causes were most frequent (61%), followed by malignancy-related (15%) and trauma (8%). In-hospital mortality occurred in 8.5% of cases, 46.5% were readmitted to the hospital within 1 year, and 49.1% of patients had resolution of the splenial DR at the next scan. Backward stepwise regression models showed that mass effect was negatively associated with splenial DR resolution (odds ratio [OR]: 0.12, confidence interval [CI] 0.03-0.46, p = 0.002). Encephalopathy was significantly associated with in-hospital mortality (OR: 4.50, CI 1.48-17.95, p = 0.007). Patients with a CLOCC had less frequent readmissions at 1-year compared with patients without a CLOCC, p = 0.015.

Discussion

Vascular DR lesions of the splenium were more common than CLOCCs and other etiologies in this cohort. While splenial DR lesions can present a clinical challenge, their associated clinical and radiographic characteristics may predict outcome and guide prognosis.

Reversible splenial lesion syndrome in children: a retrospective study of 130 cases

Background

Reversible splenial lesion syndrome (RESLES) is a new clinico-radiological syndrome. We retrospectively analyzed the clinical features of 130 children with RESLES in China, which is the largest case series available in the literature.

Methods

The clinical data of children diagnosed as RESLES in Jiangxi Provincial Children's Hospital between 2017 and 2023 were retrospectively analyzed. The 130 cases were divided into two groups: ≤ 3 years old group (group A) (n = 83) and > 3 years old group (group B) (n = 47). The chi-squared test or Fisher's test was used to evaluate the data.

Results

The vast majority of patients (127/130 cases, 97.7%) had prodromal symptoms of infection. Preceding infections of the gastrointestinal tract were statistically more significant in group A (60/83, 72.3%) than in group B (11/47, 23.4%) (P < 0.05). Preceding infections of the respiratory tract were statistically more significant in group B (33/47, 70.2%) than in group A (17/83, 20.5%) (P < 0.05). Seizures were statistically more significant in group A (82/83, 98.8%) than in group B (24/47,51.1%) (P < 0.05). The disturbance of consciousness and headache/dizziness were statistically more significant in group B (27/47, 57.4%; 37/47, 78.7%) than in group A (3/83, 3.6%; 1/83, 1.2%), respectively (P < 0.05). Convulsions with mild gastroenteritis (CwG) were statistically more significant in group A (50/83, 60.2%) than in group B (8/47, 17.0%) (P < 0.05). However, encephalitis/encephalopathy was statistically more significant in group B (20/47, 42.6%) than in group A (10/83, 12.0%) (P < 0.05). MRI showed cytotoxic edema in typical locations (RESLES type-1 limited to the splenium of the corpus callosum and RESLES type-2 spread to the entire corpus callosum, adjacent white matter, or both). There was full recovery of the lesions of MRI in all cases from 3 days to 50 days after the initial examinations. All the children showed normal neurodevelopment.

Conclusion

Infection was the most common cause of RESLES. Infections of the gastrointestinal tract are common in ≤ 3 years old children, while infections of the respiratory tract are common in >3 years old children. Younger patients are more likely to develop convulsions, and older children were more likely to have symptoms with disturbance of consciousness and headache/dizziness. RESLES has characteristic MRI manifestations and a good prognosis.

Case report: Reversible splenial lesion syndrome caused by diquat poisoning

Diquat (DQ), chemically known as 1,1 '-ethylene-2,2' -bipyridine, is a non-selective herbicide for leaf removal and drying. It has toxic effects on central nervous system cells, and toxic neurological lesions include axonal degeneration and pontine myelolysis. At the same time, DQ can also affect the activity of dopaminergic nerve cells through oxidative stress, causing degeneration and reducing dopamine uptake. With the increasing application of DQ in agricultural production, the clinical reports of neurotoxicity caused by acute DQ poisoning are also increasing. At present, DQ rapid-phase-related toxic encephalopathy mainly involves the pons, midbrain, basal ganglia, thalamus and other brain regions. However, this case is unusual in that the lesion mainly involved the splenium of the corpus callosum. It is also the first time to be reported.

Reversible splenial lesion syndrome type II in youth mimicking acute ischemic stroke like onset: A case report

BACKGROUND

Reversible splenial lesion syndrome (RESLES) is a newly recognized syndrome. Its typical pathologic findings is a reversible progress correlated with transiently reduced diffusion lesion in the splenium of the corpus callosum. The common clinical symptoms include mildly altered states consciousness, delirium, and seizure.

METHODS

We presented a 21-year-old patient with signs of acute ischemic stroke (AIS), including symptoms of weakness on the right upper limb and aphasia, lasting 50 minutes until he was taken to the emergency. He just had a cough 20 days ago.

RESULTS

An elevated level of white blood cell count, neutrophil count, monocyte count, protein of cerebrospinal fluid was found in laboratory examinations. Magnetic resonance imaging revealed distinct lesions involving white matter in the splenium of the corpus callosum and frontal-parietal cortex on both cerebral hemispheres. Digital subtraction angiography examination was also unremarkable. The patient recovered to baseline within 4 days. We treated the patient with glucocorticoid, antiviral drugs, butylphthalide, and dehydrating drugs. In addition, the follow-up brain magnetic resonance imaging scan showed reduced lesions. AIS-like symptoms did not occur during a 30-day follow-up period.

CONCLUSION

This patient with reversible splenial lesion syndrome type II exhibited AIS-like symptoms, which was uncommon on clinical. This case extends the recognized clinical phenotypes for this disorder.

Transient splenial lesion syndrome in bipolar-II disorder: a case report highlighting reversible brain changes during hypomanic episodes

Background

Reversible splenial lesion syndrome (RESLES) is a rare neurological condition characterized by temporary abnormalities in the splenium of the corpus callosum, which has been reported in mental disorders. Previous studies on bipolar disorder (BD) primarily focused on aspects such as brain structure and function, neurochemical changes, and genetics. However, there have been no studies reporting the occurrence of this syndrome during hypomanic episodes and its disappearance during the remission phase in bipolar disorder type 2 (BD-II).

Case presentation

We present a case report of a 30 years-old female patient with BD-II who exhibited symptoms of RESLES during a hypomanic episode. The patient, with a 12 years psychiatric history, has experienced recurrent depressive episodes initially, with the first hypomanic episode occurring 8 years ago. During this period, this patient made several visits to the outpatient clinic to have her medications adjusted due to repeated suicide attempts. This time, she was admitted to our hospital with a second hypomanic episode due to drug withdrawal during pregnancy. The RESLES was observed on her brain magnetic resonance image, and it was alleviated after treatment with lithium carbonate and quetiapine until achieving remission.

Conclusion

We present the first report of identifying RESLES in BD-II with hypomanic episodes, which subsequently disappears during the remission phase. Our case report highlights a potential association between BD and RESLES, emphasizing the need for future studies to explore the underlying mechanisms connecting these two conditions in greater depth.

Reversible splenial lesion after surgery for distant arteriovenous malformation: a case report

Isolated lesions of the corpus callosum are rare and may represent permanent but also transient responses to various pathology termed "reversible splenial lesion syndrome" (RESLES) when in light of relevant clinical presentation. We present the first case of the RESLES after elective surgery for distant arteriovenous malformation (AVM), followed by a slight speech disturbance and MRI verified small, oval, well-circumscribed area of apparent cytotoxic edema in the center of the corpus callosum splenium, which completely resolved within 15 days. Surgery for AVM is followed by the complex adaptation to a new vascular pattern, RESLES might develop, and should be suspected.

Autoimmune glial fibrillary acidic protein astrocytopathy coexistent with reversible splenial lesion syndrome: A case report and literature review

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a rare autoimmune disorder. Reversible splenial lesion syndrome (RESLES) is a transient clinical-imaging syndrome characterized by specific magnetic resonance imaging (MRI) pattern. A 58-year-old man was admitted with a fever, headache, and confusion for 1 week. Brain MRI showed abnormal leptomeningeal enhancement in the brainstem and high signal intensity on diffusion-weighted MRI of the corpus callosum. Anti-GFAP antibody was positive in the serum and cerebrospinal fluid analysis. This patient significantly improved and had no relapse after glucocorticoid and immune suppressant therapy. A repeated brain MRI revealed the lesion in the corpus callosum and abnormal leptomeningeal enhancement in the brainstem disappeared. Linear perivascular radial enhancement is the characteristic pattern of autoimmune GFAP astrocytopathy which is rarely coexistent with RESLES.

An elderly man with mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) without neuropsychiatric sequelae

Mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is less common in the elderly, and most have some sequelae. However, even in the elderly, MERS may have a good prognosis, and a specific treatment is not always required.

Autoimmune Glial Fibrillary Acidic Protein (Gfap) Astrocytopa-Thy Accompanied with Reversible Splenial Lesion Syndrome (RESLES): A Case Report and Literature Review

BACKGROUND

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy usually presents as meningoencephalomyelitis. Many patients developed flu-like symptoms preceding the neurologic symptoms. Reversible lesion in the splenium of the corpus callosum (SCC) is a clinical and radiological syndrome secondary to many kinds of etiologies, including infections, which is termed RESLES.

CASE PRESENTATION

we reported a case developing irregularly high fever, both temporal pain, low limbs fatigue with frequent urination admitted to our neurology department. CSF test showed GFAP-IgG positive, elevated WBC counts and protein, with low glucose and chlorine, while MRI showed a reversible lesion on SCC, leading us to diagnose autoimmune GFAP autocytopathy accompanied with RESLES. The boy had significantly improved after anti-virus and steroids therapy.

DISCUSSION

Autoimmune GFAP autocytopathy accompanied with RESLES is rarely seen, and pathogenesis for the co-existence has not been clarified. Autoimmune GFAP autocytopathy and RESLES are both related to viral infection. Our case covered infectious symptoms and improved after antiviral treatment, suggesting virus infection may perform a key role in pathogenesis.

Metabotropic glutamate receptor 5-related autoimmune encephalitis with reversible splenial lesion syndrome following SARS-CoV-2 vaccination

RATIONALE

Metabotropic glutamate receptor 5 (mGluR5)-related autoimmune encephalitis (AE) has been rarely reported; however, there are no reports on mGluR5-related AE with reversible splenial lesion syndrome following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

PATIENT CONCERNS

A 29-year-old man was admitted with a history of headache and fever for 9 days and 6 days, respectively.

DIAGNOSIS

He was initially diagnosed with an intracranial infection, however the final diagnosis was corrected as anti-mGluR5-related AE with reversible splenial lesion syndrome.

INTERVENTIONS

He had received an inactivated SARS-CoV-2 vaccine 3 weeks prior to the examination and was initially diagnosed with an intracranial infection. Physical examination revealed bilateral horizontal nystagmus, ataxia, and neck rigidity. Antiinfective therapy was minimally helpful. An analysis of the cerebrospinal fluid did not reveal pathogens for sequencing. Magnetic resonance imaging displayed abnormal signals in the splenium of the corpus callosum.

OUTCOMES

We identified mGluR5 antibodies in the cerebrospinal fluid and serum. Subsequently, intravenous methylprednisolone pulse and gamma-globulin pulse therapies were administered, which substantially improved the symptoms. Follow-up did not reveal abnormal neurological symptoms, and the lesion in the corpus callosum had resolved.

LESSONS

AE with mGluR5 antibodies could arise from SARS-CoV-2 vaccination, which warrants the awareness of healthcare workers. Reversible splenial lesion syndrome may accompany mGluR5-related AE and mimic intracranial infection. Thus, early treatment can prevent serious residual signs and symptoms.

Case report: Autoimmune encephalitis with multiple auto-antibodies with reversible splenial lesion syndrome and bilateral ovarian teratoma

Background

Reversible splenial lesion syndrome (RESLES) is a spectrum of disease radiologically characterized by reversible lesions caused by multiple factors, primarily involving the splenium of the corpus callosum (SCC). The most common causes of RESLES include infection, antiepileptic drug use and withdrawal, and severe metabolic disorders. Nevertheless, cases of autoimmune encephalitis (AE) are uncommon.

Case presentation

A 26-year-old female computer programming engineer with no previous medical or psychiatric history reported to the psychiatric hospital due to a 3-day episode of irritability, babbling, limb stiffness, sleepwalking, hallucinations, and paroxysmal mania. Brain MRI revealed abnormal signals of the SCC. Lumbar puncture was performed and further testing for auto-antibodies was conducted in both the CSF and serum. CSF of the patient was positive for anti-NMDAR (titer of 1:3.2) antibodies, and serum was also positive for anti-NMDAR (titer of 1:32) as well as mGluR5 (titer of 1:10) antibodies. Enhanced CT of the pelvis showed an enlarged pelvic mass; bilateral ovarian teratomas (mature teratoma and immature teratoma) were evaluated, which were pathologically confirmed after transabdominal left adnexal resection, right ovarian biopsy, and ovarian cystectomy. The patient considerably improved after intravenous administration of steroids, immunoglobulin, oral prednisone, surgical treatment, and chemotherapy. A follow-up MRI revealed completely resolved lesions. During a 3-month follow-up, the patient experienced complete resolution of symptoms without any sign of recurrence and tumors. The titer of the anti-NMDAR antibody decreased to 1:10 in serum.

Conclusion

Herein, we report a rare case of AE with overlapping auto-antibodies, along with RESLES and bilateral ovarian teratomas. The current case provides the possibility of the concurrence of mGluR5 antibodies in anti-NMDAR encephalitis. However, the underlying mechanism remains elusive. Furthermore, we provide additional evidence that overlapping antibodies-related pathology may be one of the many causes of RESLES. Nonetheless, caution should be observed in interpreting the observation, considering that this is a single-case study.

Cytotoxic Lesions beyond the Corpus Callosum Following Acute Meningoencephalitis and Mycoplasma Pneumoniae Infection: A Case Report and Literature Review

Cytotoxic lesions of the corpus callosum (CLOCCs) are secondary lesions associated with a variety of clinical causes. The presence of a small and reversible lesion in the splenium of corpus callosum with restricted diffusion on cranial magnetic resonance imaging is the defining feature. The clinical-radiological manifestations have been documented as mild and reversible. Severer presentations were scarcely reported. In this report, we described a 25-year-old man with preceding fever, worsening somnolence, and convulsions. He was diagnosed with acute meningoencephalitis and Mycoplasma pneumoniae infection after workups. After medical treatments, he had neurological deterioration and progressing CLOCCs from a small oval lesion in the center of splenium extending to the whole corpus callosum and bilaterally adjacent white matter. The patient received intravenous methylprednisolone and immunoglobulin successively, and his neurological conditions improved. The CLOCCs, not always mild and reversible, could present with severe clinicoradiological features.

Cytotoxic corpus callosum lesion and mild CSF pleocytosis during hantavirus infection: a case report

A middle-aged, previously healthy male patient presented with high fever, headache, and aching limbs for 3 days. Laboratory results showed signs of acute kidney injury, elevated procalcitonin, and mild thrombocytopenia. On neurological examination, he had no focal neurological deficits, especially no meningism or visual disturbances. Cerebrospinal fluid (CSF) examination showed mild lymphocytic pleocytosis, and magnetic resonance imaging (MRI) revealed a lesion of the splenium corporis callosum. The patient received anti-infective treatment with acyclovir and ceftriaxone until laboratory results returned positive hantavirus IgM and IgG antibodies in the serum indicating an active hantavirus infection. The renal retention parameters and thrombocytopenia receded following treatment with intravenous fluids, analgesic, and antipyretic agents. MRI follow-up 10 days later showed a residual small FLAIR-positive lesion without any persistent callosal diffusion abnormality. The patient was discharged symptom-free after 8 days and had recovered fully 2 months later. The source of infection in this patient remained unclear. Cytotoxic lesions of the corpus callosum (CLCC) are secondary lesions usually with a good prognosis but require further investigation regarding their underlying etiology and should not be confounded with primary callosal lesions, such as ischemia or lymphoma.

Non-severe COVID-19 complicated by cytotoxic lesions of the corpus callosum (mild encephalitis/encephalopathy with a reversible splenial lesion): a case report and literature review

BACKGROUND

Coronavirus disease 2019- (COVID-19-) associated cytotoxic lesions of the corpus callosum (CLOCCs) have been reported as a rare neurological abnormality in severe cases. Here, a case of CLOCCs in the early stages of mild COVID-19 infection during the Omicron BA.1 epidemic is reported along with a literature review.

CASE REPORT

A Japanese woman with COVID-19 presented to the emergency department with altered consciousness and cerebellar symptoms a day after fever onset. Magnetic resonance imaging (MRI) revealed a lesion with restricted diffusion in the corpus callosum. She exhibited no complications of pneumonia, her neurological symptoms resolved after two days, and after 10 days, the brain lesion was not detected on MRI.

LITERATURE REVIEW

The PubMed database was searched for case reports that met the CLOCC definition proposed by Starkey et al. The search yielded 15 COVID-19-associated cases reported as CLOCCs and 13 cases described under former terms, including mild encephalitis/encephalopathy with a reversible splenial lesion. Adult cases with a documented course were accompanied by pneumonia or hypoxemia, whereas pediatric cases were mostly accompanied by a multisystem inflammatory syndrome.

CONCLUSION

COVID-19-associated CLOCCs can occur, even at an early, non-severe stage. Therefore, this condition may be underdiagnosed if MRI is not performed.

Case report: Reversible encephalopathy associated with liposomal amphotericin B in a patient with cryptococcal meningitis

Liposomal amphotericin B (L-AMB) is an anti-fungus medicine that has fewer side effects than traditional amphotericin B (AMB). Neurotoxicity of L-AMB has rarely been observed, and only one case of leukoencephalopathy during intravenous L-AMB has been reported. Herein, we described a patient with cryptococcal meningitis presenting with late-onset reversible encephalopathy associated with liposomal amphotericin B.

Reversible splenial lesion syndrome (RESLES): Two patients as study cases

Reversible splenial injury syndrome (RESLES) is a rare clinicoradiological entity that defines a reversible lesion in the splenium of the callosum in magnetic resonance imaging.

RESLES may be of infectious iatrogenic or metabolic origin. We report 2 cases of drug induced RESLES in our training.

The presence of an isolated lesion of the corpus callosum in a context of polymedication by psychotropic drugs and the regression in less than 4 weeks suggests a toxic origin, in particular medicinal.

The pathophysiology of these reversibles lesions of the splenium of callosum is not very clear, most often it is a phenomenon of vasogenic edema that is evoked, the clinical symptoms are very varied and nonspecific, and the prognosis is generally good in the absence of underlying disorder.

Reversible Splenial Lesion Syndrome (RESLES) after Nitrous Oxide Abuse: A Case Report

Background: Reversible splenial-lesion syndrome (RESLES) is a relatively rare and underrecognized clinical-imaging syndrome involving the splenium of the corpus callosum (SCC). RESLES can be caused by various etiologies. Case description: An 18-year-old man with no previous history of neurological or psychiatric disorders presented to our hospital with headache, intermittent blurred vision, and limb weakness after 150 days of recreational nitrous-oxide abuse. The patient’s serum vitamin B12 concentration was normal, and magnetic-resonance imaging (MRI) examination revealed isointensity on T1-weighted imaging (T1WI) of the corpus callosum and high signal intensity on T2WI, T2FLAIR, and diffusion-weighted MRI (DWI); thus, a diagnosis of RESLES was established. The patient received 0.5 mg of mecobalamin daily and nitrous oxide was discontinued. After 4 weeks, the patient’s symptoms disappeared and the imaging examination revealed normal findings. Conclusion: We report for the first time a case of headache, blurred vision, and hallucination caused by RESLES associated with nitrous-oxide abuse. In cases of headaches and hallucinations of unknown etiology, the possibility of RESLES caused by nitrous oxide abuse should be considered.

Transient splenial lesions of the corpus callosum and infectious diseases

Transient splenial lesion of the corpus callosum can be observed in various diseases such as cancer, drug use, metabolic disorders, and cerebrovascular disorders, as well as in patients with infectious diseases. During the coronavirus disease 2019 (COVID-19) pandemic, there were increasing reports of these lesions being detected on brain imaging tests performed in patients with neurological symptoms. On brain magnetic resonance imaging, findings suggestive of cytotoxic edema are observed in the splenium; these are known to disappear with improvement of clinical symptoms. Cytokinopathy caused by infection increases the permeability of the blood–brain barrier and activates the glial cells of the brain to induce cytotoxic edema. Most patients have a good prognosis. The causes, mechanism, diagnosis, treatment and prognosis of transient splenial lesions of the corpus callosum will be summarized in this review.

Reversible Splenial Lesion Syndrome as a Challenging Casuistry

The corpus callosum plays a vital role in brain function. In particular, in the trunk of the corpus callosum, in the course of various diseases, there may be temporary, reversible changes (reversible splenial lesion syndrome (RESLES)), as well as partially reversible and irreversible changes. This article discusses the differentiation of RESLES and other conditions with changes in the corpus callosum lobe, as well as the accompanying clinical symptoms. Moreover, a case report of a patient in whom the above changes appeared in the nuclear magnetic resonance (NMR) image is presented. A 20-year-old patient with the diagnosis of Ehlers-Danlos syndrome type VI was admitted to the psychiatric ward in an emergency because of psychomotor agitation, refusal to take food and fluids, delusional statements with a message, grandeur, and auditory hallucinations. In the performed magnetic resonance imaging (MRI) of the brain, the corpus callosum non-characteristic in T2-weighted images revealed a hyperintensive area, which was significantly hyperintensive in diffusion magnetic resonance (DWI) sequences and in apparent diffusion coefficient (ADC) sequences with reduced signal intensity and no signs of bleeding. The hypothesis of subacute ischemic stroke of the corpus callosum was presented. In the control MRI of the brain, changes in the corpus callosum completely regressed, thus excluding an ischemic etiology and favoring the diagnosis of RESLES. During hospitalization, the patient experienced significant fluctuations in mental status, with the dominant symptoms typical of the paranoid syndrome in the form of disturbances in the course and structure of thinking and perception, and a clear and stable improvement was obtained after the administration of long-acting intramuscular olanzapine. Taking into account the clinical and radiological picture, the age of the episode, the rapidity of the disease development, the persistence of its clinical symptoms after the withdrawal of radiological changes in the brain NMR image, as well as the significant improvement in the clinical condition after the introduction of antipsychotic drugs, the final diagnosis was made of schizophrenia.

Adult mild encephalitis with reversible splenial lesion and catatonia: A case report

The relationship between corpus callosum and schizophrenia is elusive. Neuropsychiatric symptoms in Mild encephalitis with reversible splenial lesion (MERS) such as delirium, and negativism, suggest a link between corpus callosum and psychiatric disturbances.

Here in, we report catatonia as an initial symptom of MERS in a schizophrenic patient.

The aim of this study is to discuss the likely causal relationship between catatonic syndrome and MERS.

To the best of our knowledge, the catatonia was not reported before as a prodromal symptom of MERS. We therefore report this case in order to enlarge the spectrum of MERS symptoms in psychiatric patients and discuss the relationship between catatonia and splenium lesions.

Shigella-associated mild encephalitis with reversible splenial lesion in Hospital Center Delafontaine, Saint-Denis, France: a case report

BACKGROUND

Mild encephalitis with reversible splenial lesion of the corpus callosum (MERS) is a clinical/radiological syndrome characterized by hyperintense signal changes in the splenium of the corpus callosum visible on diffusion weighted imaging (DWI) in the brain Magnetic Resonance Imaging (MRI) associated with various neurological symptoms. Progression is usually favorable with disappearance of the MRI brain lesion and regression of clinical symptoms over a few days to a few weeks. The exact pathophysiology remains unclear. MERS can be associated with various pathogens.

CASE PRESENTATION

We report here a paediatric case of MERS associated with Shigella flexneri infection. A five-year-old boy with no relevant past medical history presented with symptoms such as headache, fever, profuse diarrhea and hallucinations. A brain Magnetic Resonance Imaging performed on Day 2 of the symptoms revealed hyperintense signal changes of the splenium of the corpus callosum in T2 FLAIR sequence. This infection had a favorable outcome after antibiotic therapy. No further recurrence of symptoms was observed and a follow-up clinical examination eight weeks later was normal. A follow-up brain Magnetic Resonance Imaging three months after discharge was also normal and the hyperintense signal changes of the splenium of the corpus callosum had disappeared completely.

CONCLUSIONS

MERS is a clinical/radiological syndrome with a generally good prognosis. We believe that this is the first description of a case of Shigella-associated MERS. It is useful to know about this condition to help distinguish it from acute disseminated encephalomyelitis.

Can plasma exchange therapy be an option for the treatment of SARS-CoV-2 Related Splenial Lesion Syndrome: Two cases from the pediatric intensive care unit

Background

Reversible splenial lesion syndrome (RESLES) is characterized by a temporary lesion in the splenium of the corpus callosum. RESLES is one of the most common causes of Mild encephalitis/encephalopathy reversible splenial lesion (MERS) and a rare clinical syndrome for the pediatric population. In a limited number of pediatric case reports, association with SARS-COV-2 in was reported. We aimed to increase the awareness of neurological involvement and treatment options of RESLES in children diagnosed with MIS-C.

Case presentation

We report two cases with a diagnosis of multisystem inflammatory syndrome-children who developed RESLES during the disease course. Fever, blurred vision, ataxia and encephalopathy were the main central nervous system symptoms. In our first case, we observed a rapid recovery in clinical symptoms and complete resolution of the splenial lesion in with intravenous immunoglobulin (IVIG) and methylprednisolone treatment. However, our second case did not respond to IVIG and methylprednisolone treatment. We performed therapeutic plasma exchange therapy and observed a successful recovery both in brain magnetic resonance imaging and echocardiographic findings.

Conclusion

Although IVIG and methylprednisolone are the first choice treatment methods in MIS-C cases progressing with RESLES, therapeutic plasma exchange may be an option for the treatment of unresponsive cases.

Surgery for intractable epilepsy after severe encephalopathy with reversible splenial lesion and new onset hippocampal lesion associated with parechovirus

We describe a case of severe encephalopathy with reversible splenial lesion associated with parechovirus, followed by intractable temporal lobe epilepsy (TLE), which was improved by epilepsy surgery. A 3-year-old girl was admitted because of fever, consciousness disturbance and generalized tonic clonic seizure. Her seizure lasted for four hours. Fluid-attenuated inversion recovery (FLAIR) showed a hyperintensity in the splenium of the corpus callosum. Electroencephalogram (EEG) demonstarated continuous diffuse epileptic activity represented by synchronous and rhythmic high-amplitude spikes and waves, which led to the diagnosis of status epilepticus. Her consciousness was improved with fosphenytoin, midazolam and methylprednisolone pulse after 3 days. Seven days later, FLAIR hyperintensity in the splenium of the corpus callosum was disappeared; however, a hyperintensity in the right hippocampus was detected. Since the stool examination was positive for parechovirus, her final diagnosis was reversible splenial lesion syndrome (RESLES) associated with parechovirus. At age 8, she experienced epigastric sensation and consciousness disturbance once a week. Based on the scalp EEG and radiological findings, she was diagnosed with intractable right TLE. We performed a right selective amygdalohippocampectomy and anterior temporal disconnection at 10 years of age. One year and 3 months after surgery, she was seizure free. To our knowledge, this is the first report of severe febrile epilepticus status. with RESLES associated with parechovirus, followed by intractable TLE, which was resolved by epilepsy surgery.

Mild Encephalitis/Encephalopathy with Reversible Splenial Lesion Associated with Scrub Typhus in a Child: A Case Report

Background: Mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is a rare clinicoradiological syndrome characterized by transient mild encephalopathy and magnetic resonance imaging (MRI) findings of a reversible lesion in the splenium of the corpus callosum (SCC). Multiple causes have been proposed for the pathogenesis of MERS, with infection as the most pre-eminent. Case Presentation: We report the case of a 10-year-old girl with MERS due to scrub typhus. Her clinical manifestations of headache and drowsiness, together with lesions involving the SCC, as shown by MRI, and their complete resolution upon follow-up fulfilled the diagnosis of MERS. At the same time, the characteristic eschar of the skin and the positive Weil-Felix test result confirmed the existence of scrub typhus infection. Conclusions: To the best of our knowledge, we described the first pediatric case of MERS associated with scrub typhus. The case indicated that an MERS patient with fever should be considered as possibly having a scrub typhus infection. The characteristic black eschar of scrub typhus generally occurs after bite of mite that is important and useful to the doctor for making proper diagnosis.

Altered gene expression in human brain microvascular endothelial cells in response to the infection of influenza H1N1 virus

Influenza viruses not only cause respiratory illness, but also have been reported to elicit neurological manifestations following acute viral infection. The central nervous system (CNS) has a specific defense mechanism against pathogens structured by cerebral microvasculature lined with brain endothelial cells to form the blood–brain barrier (BBB). To investigate the response of human brain microvascular endothelial cells (hBMECs) to the Influenza A virus (IAV), we inoculated the cells with the A/WSN/33 (H1N1) virus. We then conducted an RNAseq experiment to determine the changes in gene expression levels and the activated disease pathways following infection. The analysis revealed an effective activation of the innate immune defense by inducing the pattern recognition receptors (PRRs). Along with the production of proinflammatory cytokines, we detected an upregulation of interferons and interferon-stimulated genes, such as IFN-β/λ, ISG15, CXCL11, CXCL3 and IL-6, etc. Moreover, infected hBMECs exhibited a disruption in the cytoskeletal structure both on the transcriptomic and cytological levels. The RNAseq analysis showed different pathways and candidate genes associated with the neuroactive ligand-receptor interaction, neuroinflammation, and neurodegenerative diseases, together with a predicted activation of the neuroglia. Likewise, some genes linked with the mitochondrial structure and function displayed a significantly altered expression. En masse, this data supports that hBMECs could be infected by the IAV, which induces the innate and inflammatory immune response. The results suggest that the influenza virus infection could potentially induce a subsequent aggravation of neurological disorders.