Long-term outcomes of paediatric Guillain-Barré syndrome.

AIM: To study long-term sequelae in children with Guillain-Barré syndrome (GBS). METHOD: This was a prospective observational study with children from two French tertiary centres. Data were from clinical and several standardized scales or questionnaires. RESULTS: Fifty-one patients were included with a median follow-up of 6 years 4 months (range 3-20 years) after the acute phase. The sequelae rate was 67% (95% confidence interval [CI] 53-78) and did not vary with time. Most children had minor sequelae (Guillain-Barré Syndrome Disability Score [GBSDS] = 1); only one was unable to run (GBSDS = 2). The most frequent complaints were paraesthesia (43%), pain (35%), and fatigue (31%). The neurological examination was abnormal in 18% of children, autonomy was compromised in 14%, and symptoms of depression occurred in 34%. The factors associated with late-onset sequelae were correlated with severity during the initial phase (i.e. initial GBSDS >4, odds ratio 6.6, 95% CI 1.8-33; p = 0.009). The predictive factors of more severe late-onset conditions were initial severity (p = 0.002) and sex (female patients; p = 0.01). INTERPRETATION: Two-thirds of children with GBS had late-onset sequelae following an episode, often minor, but sometimes with continuing effects on their everyday lives. Particularly affected were those who had severe GBS during the acute phase and who lost the ability to walk. WHAT THIS PAPER ADDS: Two-thirds of children with Guillain-Barré syndrome (GBS) had persistent sequelae. Sequelae were often minor, but daily repercussions of them were sometimes serious. Sequelae were significantly associated with severe GBS during the acute phase.

Long-term outcome of paediatric anti-N-methyl-D-aspartate receptor encephalitis.

AIM: To study long-term clinical and cognitive outcomes of patients with anti-N-methyl-d-aspartate receptor encephalitis (NMDAR-E), an acute autoimmune neurological disease with severe acute presentations. METHOD: In this French multicentre retrospective observational cohort study, patients no older than 18 years with a follow-up of at least 2 years were included. Data from clinical and cognitive assessments were collected. RESULTS: Eighty-one patients were included (57 females, 24 males; median age 10 years 7 months [range 1-18 years], median follow-up 40 months [range 25-53 months]). At last follow-up, 35 patients (45%) had cognitive impairment, 48 (70%) had academic difficulties, and 65 (92%) needed rehabilitation. Seventy-one patients (88%) had a modified Rankin Scale score of no more than 2. A higher number of symptoms at diagnosis was associated with cognitive impairment (p = 0.01), while an abnormal electroencephalogram at diagnosis increased the risk of academic difficulties (p = 0.03). INTERPRETATION: Although most children with NMDAR-E seemed to recover from motor disabilities, more than 45% had cognitive and academic difficulties. The initial severity of symptoms seems to have an impact on cognition and academic performances. WHAT THIS PAPER ADDS: Forty-five per cent of patients had cognitive impairment at ≥2 years diagnosis of anti-N-methyl-d-aspartate receptor encephalitis (NMDAR-E). Seventy per cent of patients had academic difficulties at ≥2 years diagnosis of NMDAR-E. Ninety-two per cent of patients needed rehabilitative care at ≥2 years diagnosis of NMDAR-E. A high number of symptoms at diagnosis were associated with cognitive impairment.

Stiff Person Syndrome and Encephalitis with GAD Antibodies with Severe Anterograde Amnesia in an Adolescent: A Case Study and Literature Review.

Antiglutamic acid decarboxylase (GAD65) encephalitis is rare and few pediatric cases have been reported, with variable clinical presentations. A 14-year-old female adolescent was managed in our department. She had been treated for several months for drug-resistant temporal lobe epilepsy and gradually presented major anterograde amnesia with confusion. Upon her arrival at the University Hospital Centre, she showed a classical form of stiff person syndrome. The brain magnetic resonance imaging showed bitemporal hyperintensities and hypertrophy of the amygdala. The blood and cerebrospinal fluid were positive for GAD65 antibodies. At 2 years of immunosuppressive treatment and rehabilitation, the course showed partial improvement of the memory and neuropsychiatric impairment, and epilepsy that continued to be active. GAD65 antibodies are associated with various neurological syndromes, and this presentation combining limbic encephalitis and stiff person syndrome is the first pediatric form published to date; there are also few cases described in adults.

Post-CMV Guillain-Barré Syndrome with Anti-GM2 Antibodies: Two Cases and a Review of the Literature.

INTRODUCTION: Guillain-Barré syndrome (GBS) is an acute post-infectious inflammatory polyneuropathy of ubiquitous distribution. Cytomegalovirus (CMV) is the virus that is most frequently involved. All ages are affected but rare pediatric cases seem to show some distinctive features in terms of specificity and severity. Specific antibodies that target the peripheral nervous system have been identified in several forms of GBS in adults, such as anti-GM2 ganglioside antibodies in post-CMV GBS, which in most instances present as demyelinating polyneuropathies, with a more favorable progression and fewer complications. MATERIALS AND METHODS: This is a retrospective report on two cases of post-CMV GBS with a demyelinating disorder and positive for anti-GM2 IgM. The review of the literature examines five other cases of children with post-CMV GBS with anti-GM2 IgM. RESULTS: In terms of progression, our two cases of post-CMV GBS with a demyelinating disorder and anti-GM2 IgM are similar to the five other cases described in the literature. The CMV infection was asymptomatic or paucisymptomatic and involved girls (6/7), often presenting severe motor forms with frequent loss of the ability to walk (4/6), facial involvement (⅗), little respiratory involvement (⅙), and favorable progression with adapted treatment. CONCLUSION: Post-CMV GBS with anti-GM2 IgM is a specific clinical spectrum that seems to affect children as it affects adults with a predominance among females, demyelination, and severe motor involvement, but a good prognosis. On the other hand, unlike adults, the use of assisted ventilation does not seem to be more frequent.

Neonatal Herpes Simplex Virus-1 Recurrence with Central Nervous System Disease in Twins after Completion of a Six-Month Course of Suppressive Therapy: Case Report.

Seventeen-day-old twins were hospitalized for neonatal herpes simplex virus 1 (HSV-1) with central nervous system disease and internal capsule and thalamic lesions on magnetic resonance imaging (MRI). They were treated with the usual intravenous (IV) treatment and oral therapy for 6 months. The clinical course was good in both children with negative HSV polymerase chain reaction on completion of IV therapy. The neurological condition recurred in one child with new radiological lesions at 7 months of age, 2 weeks after discontinuation of oral treatment. Cerebral lesions highlighted on the MRI scan are specific to the neonatal period and impact long-term prognosis. The likely genetic predisposition in this case is interesting and requires further investigation. In addition, this case raises questions about the duration of oral acyclovir suppressive therapy.

Prognostic factors for the sequelae and severity of Guillain-Barré syndrome in children.

INTRODUCTION: Guillain-Barré syndrome (GBS) is an inflammatory polyradiculoneuritis. Our aim in this study was to describe the clinical characteristics and the long-term sequelae of GBS in a French pediatric population. METHODS: In this multicenter, retrospective study we evaluated clinical signs, radiological examinations, laboratory tests, treatments, and outcomes. RESULTS: One hundred ten children were included in this investigation. These children presented with walking difficulties, muscle weakness, and cranial nerve impairment. Electrodiagnostic testing revealed 70% with acute inflammatory demyelinating polyradiculoneuropathy (AIDP) and 16% with acute motor axonal neuropathy (AMAN). One hundred children received immunoglobulins. At follow-up, 77% were cured, whereas 9% had sequelae, associated with an axonal form (P < .01) and a short interval between symptom onset and hospitalization (P < .01). The need for intubation was correlated with peripheral facial paralysis (P < .01) and dysautonomia (P < .01). DISCUSSION: Although AIDP and AMAN present in a similar way, the axonal form is associated with a worse outcome.

Monitoring Criteria of Intracranial Lesions in Children Post Mild or Moderate Head Trauma.

Head injury is the most common cause of child traumatology. However, there exist no treatment guidelines in children having intracranial lesions due to minor or moderate head trauma. There is little knowledge about monitoring, clinical exacerbation risk factors, or optimal duration of hospitalization. The aim of this retrospective study is to find predictive factors in the clinical course of non-severe head trauma in children, and thus to determine an optimal management strategy. Poor clinical progress was observed in only 4 out of 113 children. When there are no clinical signs and no eating disorders, an earlier discharge is entirely appropriate. Nevertheless, persistent clinical symptoms including headache, vomiting, and late onset seizure, especially in conjunction with hemodynamic disorders such as bradycardia, present a risk of emergency neurosurgery or neurological deterioration. Special attention should be paid to extradural hematoma (EDH) of more than 10 mm, which can have the most severe consequences. Clinical aggravation does not necessarily correlate with a change in follow-up imaging. Conversely, an apparent increase in the brain lesion on the scan is not consistently linked to a pejorative outcome.

Plasma Exchange and Immunoadsorption in Pediatric Inflammatory Optic Neuropathy Resistant to Corticosteroid Therapy: Four French Cases.

Steroids as a foremost therapy are widely used in pediatric optic neuritis (ON). Yet, this treatment is not standardized to date. Some children show a resistance to the classic treatment by steroids. Although plasma exchange (PE) and immunoadsorption (IA) techniques are increasingly being adopted and lead to good results in resistant cases in adult patients, very few studies have shown interest in treating ON when steroids have failed. In this study, we report four observations of children, two of whom are treated by PE and two by IA techniques, describing the treatment protocols together with the side effects observed.

Neurological involvement related to the influenza virus in children: A 5-year single-centre retrospective study.

INTRODUCTION: Inflammation related to influenza virus infection can lead to multiple neurological presentations. Encephalitis is one of them, mostly accompanied by seizures, with different profiles depending on the epidemics and previous medical conditions. MATERIALS AND METHODS: All children presenting neurological symptoms and positive for influenza virus RNA detection in a respiratory sample between November 2018 and April 2023, hospitalized in the Department of Paediatric Neurology of Toulouse Children's Hospital, were retrospectively analysed. RESULTS: Among the 1,277 children diagnosed with influenza in our centre, 131 (10.3 %) were hospitalized for neurological features. The year 2020-2021 was marked by zero incidence of positive influenza tests, associated with the COVID-19 pandemic. Among the 131 patients included, 71.6 % were under 5 years old. Most of them (80.9 %) were infected by influenza A virus. The first neurological symptoms were mainly seizures in 73.3 % of patients. Possible or confirmed encephalitis was observed in 29 % of cases, including one acute necrotizing encephalopathy. Few children (6.1 %) presented with acute myositis. Twenty-seven patients (20.6 %) had a personal history of significant previous neurological disorders. Most patients (88.5 %) displayed a rapid favourable outcome, marked by the disappearance of their neurological symptoms within the first 2 days. Anti-epileptic drugs were introduced in 1.5 % of cases, and adapted in 16.8 %, mainly in patients with febrile status epilepticus and an abnormal EEG. CONCLUSION: Neurological features were frequently associated with influenza infection in children; most were transient. Effects on long-term neurodevelopmental outcomes need to be clarified as our follow-up was limited, especially in children with pre-existing neurological conditions.

Cerebrospinal fluid YKL-40 level evolution is associated with autoimmune encephalitis remission.

Objective: Because of its heterogeneity in clinical presentation and course, predicting autoimmune encephalitis (AIE) evolution remains challenging. Hence, our aim was to explore the correlation of several biomarkers with the clinical course of disease. Methods: Thirty-seven cases of AIE were selected retrospectively and divided into active (N = 9), improved (N = 12) and remission (N = 16) AIE according to their disease evolution. Nine proteins were tested in both serum and cerebrospinal fluid (CSF) at diagnosis (T0) and during the follow-up (T1), in particular activated MMP-9 (MMP-9A) and YKL-40 (or chitinase 3-like 1). Results: From diagnosis to revaluation, AIE remission was associated with decreased YKL-40 and MMP-9A levels in the CSF, and with decreased NfL and NfH levels in the serum. The changes in YKL-40 concentrations in the CSF were associated with (1) still active AIE when increasing >10% (P-value = 0.0093); (2) partial improvement or remission when the changes were between +9% and -20% (P-value = 0.0173); and remission with a reduction > -20% (P-value = 0.0072; overall difference between the three groups: P-value = 0.0088). At T1, the CSF YKL-40 levels were significantly decreased between active and improved as well as improved and remission AIE groups but with no calculable threshold because of patient heterogeneity. Conclusion: The concentration of YKL-40, a cytokine-like proinflammatory protein produced by glial cells, is correlated in the CSF with the clinical course of AIE. Its introduction as a biomarker may assist in following disease activity and in evaluating therapeutic response.

Sporadic infantile epileptic encephalopathy caused by mutations in PCDH19 resembles Dravet syndrome but mainly affects females.

Dravet syndrome (DS) is a genetically determined epileptic encephalopathy mainly caused by de novo mutations in the SCN1A gene. Since 2003, we have performed molecular analyses in a large series of patients with DS, 27% of whom were negative for mutations or rearrangements in SCN1A. In order to identify new genes responsible for the disorder in the SCN1A-negative patients, 41 probands were screened for micro-rearrangements with Illumina high-density SNP microarrays. A hemizygous deletion on chromosome Xq22.1, encompassing the PCDH19 gene, was found in one male patient. To confirm that PCDH19 is responsible for a Dravet-like syndrome, we sequenced its coding region in 73 additional SCN1A-negative patients. Nine different point mutations (four missense and five truncating mutations) were identified in 11 unrelated female patients. In addition, we demonstrated that the fibroblasts of our male patient were mosaic for the PCDH19 deletion. Patients with PCDH19 and SCN1A mutations had very similar clinical features including the association of early febrile and afebrile seizures, seizures occurring in clusters, developmental and language delays, behavioural disturbances, and cognitive regression. There were, however, slight but constant differences in the evolution of the patients, including fewer polymorphic seizures (in particular rare myoclonic jerks and atypical absences) in those with PCDH19 mutations. These results suggest that PCDH19 plays a major role in epileptic encephalopathies, with a clinical spectrum overlapping that of DS. This disorder mainly affects females. The identification of an affected mosaic male strongly supports the hypothesis that cellular interference is the pathogenic mechanism.

Influenza A(H1N1)-associated ischemic stroke in a 9-month-old child.

AIM: This study aimed to report a rare clinical course of pandemic influenza A(H1N1) infection, ischemic stroke, in a 9 month-old child. CASE: A 9-month-old girl with no previous medical problem presented to our pediatric emergency department with high fever (39°C/102°F) lasting for 48 hours. Soon after admission, she started generalized tonic-clonic seizures that ceased after 2 injections of diazepam. Six hours later, she presented 2 short episodes of partial clonic seizures of the right arm followed by monoplegia. Lumbar puncture was normal. Noncontrast computed tomographic imaging of the brain was performed and revealed an acute infarct in the left middle cerebral artery territory with no mass effect. Electroencephalogram revealed important slowing in the left hemisphere. A magnetic resonance imaging was performed the next day and confirmed an ischemic stroke in the left posterior middle cerebral artery region. Nasal swab polymerase chain reaction was positive for influenza A(H1N1) and polymerase chain reaction detection negative in cerebrospinal fluid. She fully recovered her right-arm function on day 3 and was discharged on day 10 without sequelae. COMMENTS: Seasonal influenza is known to cause neurological complications in children. Influenza increases the stroke risk especially in adults at high risk. This is a rare event in childhood, and we believe this is the first report associated with H1N1 new variant. CONCLUSIONS: Acute viral infection, notably influenza, is associated with increased susceptibility to stroke, and vaccination against influenza may reduce the risk of stroke.

Hemiplegic Migraine Associated With PRRT2 Variations: A Clinical and Genetic Study.

BACKGROUND AND OBJECTIVE: PRRT2 variants have been reported in a few cases of patients with hemiplegic migraine. To clarify the role of PRRT2 in familial hemiplegic migraine, we studied this gene in a large cohort of affected probands. METHODS: PRRT2 was analyzed in 860 probands with hemiplegic migraine, and PRRT2 variations were identified in 30 probands. Genotyping of relatives identified a total of 49 persons with variations whose clinical manifestations were detailed. RESULTS: PRRT2 variations were found in 12 of 163 probands who previously tested negative for CACNA1A, ATP1A2, and SCN1A variations and in 18 of 697 consecutive probands screened simultaneously on the 4 genes. In this second group, pathogenic variants were found in 105 individuals, mostly in ATP1A2 (42%), followed by CACNA1A (26%), PRRT2 (17%), and SCN1A (15%). The PRRT2 variations included 7 distinct variants, 5 of which have already been described in persons with paroxysmal kinesigenic dyskinesia and 2 new variants. Eight probands had a deletion of the whole PRRT2 gene. Among the 49 patients with variations in PRRT2, 26 had pure hemiplegic migraine and 16 had hemiplegic migraine associated with another manifestation: epilepsy (8), learning disabilities (5), hypersomnia (4), or abnormal movement (3). Three patients had epilepsy without migraine: 2 had paroxysmal kinesigenic dyskinesia without migraine, and 1 was asymptomatic. DISCUSSION: PRRT2 should be regarded as the fourth autosomal dominant gene for hemiplegic migraine and screened in any affected patient, together with the 3 other main genes. Further studies are needed to understand how the same loss-of-function PRRT2 variations can lead to a wide range of neurologic phenotypes, including paroxysmal movement disorder, epilepsy, learning disabilities, sleep disorder, and hemiplegic migraine.

Case Report: Late Successful Thrombectomy for Ischemic Stroke in a 2-Year-Old Child.

Despite extensive evidence of benefit of thrombectomy in adult ischemic stroke due to large-vessel occlusion in the 6-h window, its role remains uncertain in very young children. We describe hereafter the case of a 2-year-old female child who had a successful thrombectomy 9 h after stroke onset. The patient presented with right hemiplegia, central facial palsy, a normal level of consciousness, and speech difficulties. The PedNIHS score was 11. CT scan without contrast injection displayed spontaneous hyperdensity of the middle cerebral artery (MCA), with only limited early signs of ischemia (ASPECTS 8). CT angiography demonstrated occlusion of the proximal MCA with good collaterals. Thrombectomy was realized. Complete recanalization (TICI 3) was obtained under general anesthesia after two passes of a stent retriever. Time from symptoms onset to full recanalization was 9 h. The acute ischemic stroke was caused by embolic thrombus from a congenital heart disease. Clinical recovery was complete. Three months after the thrombectomy, the young patient was doing well without any neurological sequelae (PedNIHSS 0; modified Rankin Scale: 0). This case report is an example of a decision-making process to perform thrombectomy in a very young child, which included cardio-embolic etiology as a parameter that potentially might have participated to the successful outcome of the therapeutic procedure.

Case Report: Successful Cerebral Revascularization and Cardiac Transplant in a 16-Year-Old Male With Syndromic BRCC3-Related Moyamoya Angiopathy.

Background: BRCC3/MTCP1 deletions are associated with a rare familial moyamoya angiopathy with extracranial manifestations. Case: We report the case of an adolescent male presenting with progressive and symptomatic moyamoya angiopathy and severe dilated cardiomyopathy caused by a hemizygous deletion of BRCC3/MTCP1. He was treated for renovascular hypertension by left kidney homograft and right nephrectomy in infancy and had other syndromic features, including cryptorchidism, growth hormone deficiency, and facial dysmorphism. Due to worsening of the neurological and cardiac condition, he was treated by a direct superficial temporal artery to middle cerebral artery bypass to enable successful cardiac transplant without cerebral damage. Conclusions: BRCC3-related moyamoya is a devastating disease with severe heart and brain complications. This case shows that aggressive management with cerebral revascularization to allow cardiac transplant is feasible and efficient despite end-stage heart failure.

Age-dependent Mendelian predisposition to herpes simplex virus type 1 encephalitis in childhood.

OBJECTIVE: To test the hypothesis that predisposition to childhood herpes simplex virus (HSV) type 1 encephalitis (HSE) may be determined in part by human genetic factors. STUDY DESIGN: A genetic epidemiologic survey of childhood HSE (onset at age 3 months to 15 years) over a 20-year period (1985-2004) was conducted throughout France (comprising 29 university hospital neuropediatric centers). A total of 85 children fulfilled the diagnostic criteria for inclusion. Family and personal histories were obtained by face-to-face interview for 51 patients. RESULTS: No familial cases of HSE were identified in our survey; however, a high proportion (20%) of the children interviewed had a relevant family history: parental consanguinity (12% of patients), early-onset herpetic keratitis in a first-degree relative (6%), or both (2%). The narrow window of high susceptibility to HSE before age 3 years (62% of patients) further indicates that predisposition to HSE is tightly age-dependent. CONCLUSIONS: This survey suggests that childhood HSE, although sporadic, may result from Mendelian predisposition (from autosomal recessive susceptibility in particular), at least in some children. There likely is incomplete penetrance, however, which may reflect, at least in part, the impact of age at the time of HSV-1 infection.

Acute transverse myelitis following an opsoclonus-myoclonus syndrome: An unusual presentation.

Opso-myoclonus syndrome (OMS) is a very rare and severe condition. Ataxia, opsoclonus, myoclonus and/or behavioral and sleeping disturbances define that autoimmune disorder syndrome which is paraneoplastic or triggered by an infection. Here, we report a 3 year-old immunocompetent boy who developed an atypical OMS which was later complicated by an acute transverse myelitis. Screening for neuroblastoma was negative and extensive infectious screening revealed an active HHV-6 infection confirmed by blood and cerebrospinal fluid PCR. A parainfectious disease was suggested and immunosuppressive treatment was initiated. After 2 years of follow-up, the patient has a left leg paresia needing a splint and is otherwise normal. Transverse myelitis can be associated with parainfectious OMS and earlier immunosuppressive treatment in these cases may be useful especially in young and immunocompetent children.

Paediatric optic neuritis: factors leading to unfavourable outcome and relapses.

OBJECTIVES: To identify prognostic factors associated with poor visual recovery and chronic relapsing diseases, for example, multiple sclerosis (MS), in children with optic neuritis (ON) at onset. METHODS: This multicentre retrospective study included 102 children with a first ON episode between 1990 and 2012. The primary criterion was poor visual recovery determined by visual acuity, and the secondary was relapses following ON. RESULTS: Median age was 11 years, 66% were girls and mean follow-up was 24 months. 58% of children were diagnosed with idiopathic isolated ON, 22% had MS, 5% had Devic's neuromyelitis optica and 6% chronic relapsing inflammatory ON. Complete visual acuity recovery rate was 57% (95% CI=[46%-69%]) at 6 months and 71% (95% CI=[60%-81%]) at 1 and 2 years but was lower in MS (p<0.01), with recovery rate of only 27% (95% CI=[12%-54%]) at 1 year. Age ≥10 years, optic disc pallor at funduscopy and MS were the principal factors associated with poor visual recovery. Age ≥10 years, abnormal brain MRI at onset and oligoclonal banding were significantly associated with MS (p<0.01). CONCLUSION: Age ≥10, optic disc pallor and MS were associated with poor recovery. Better identification of these patients may help to adapt treatment and lead to a prospective treatment study.

Motor impairment in dyslexia: the influence of attention disorders.

Developmental dyslexia is a heterogeneous syndrome with a phonological core deficit and frequent association with other developmental disorders. Controversies exist about the influence of motor difficulties frequently encountered in dyslexia. According to different theoretical approaches, these motor impairments would reflect either a frequent co-morbid entity or a cerebellar dysfunction that could constitute the causal factor of reading disabilities. The principal aim of this study was to determine the frequency of motor impairments in a population of children with phonological dyslexia and specify possible links with attention deficit. We analysed retrospectively motor and attention abilities of 58 children with phonological dyslexia. An important sub-group of children with dyslexia (40-57% depending on the severity of motor difficulties) presented a motor impairment affecting co-ordination, balance and manual dexterity suggesting a cerebellar dysfunction. There was a significant association between attention deficit and motor impairments, with a specific impact on balance and co-ordination deficits. The comparison of performance in four groups defined according to the presence versus absence of attention deficit and motor impairment, respectively, were not in favour of a unequivocal causal link between reading disabilities and motor or attention disorders.