Optic neuritis in children and its relationship to multiple sclerosis: a clinical study of 21 children

New-Onset Vision Impairment in Children: Magnetic Resonance Imaging Findings by Age Groups

INTRODUCTION

Non-traumatic visual impairment is rare in the pediatric population, but early diagnosis and treatment of the cause is crucial to prevent long-term consequences affecting children's neurocognitive development. The authors aim to determine the most common causes of non-traumatic visual impairment in pediatric patients according to age groups by magnetic resonance imaging (MRI).

METHODS

Images of patients who underwent contrast-enhanced cranial and orbital MRI for new-onset visual impairment between June 2019 and June 2022 were retrospectively reviewed. MRI findings were categorized as tumors, idiopathic intracranial hypertension, demyelinating disorders, infections, isolated optic neuritis, and others. The patients were grouped according to age as preschoolers, schoolchildren, and adolescents. Demographic features of patients and MRI findings were collected and compared among age groups.

RESULTS

One hundred seventeen of the 238 patients had pathologic MRI findings. The most common pathologies were tumors (26.4%), idiopathic intracranial hypertension (24.7%), demyelinating disorders (18.8%), infections (11.1%), and isolated optic neuritis (7.6%). Tumors (69.2%) in preschool children, idiopathic intracranial hypertension (36.3%) in schoolchildren, and demyelinating disorders (32.7%) in adolescents were the most common cause of vision impairment by age group.

CONCLUSION

Children with acute vision impairment could have severe pathologies. Tumors in preschool children, idiopathic intracranial hypertension in schoolchildren, and demyelinating disorders in adolescents were the most common causes of new-onset vision impairment detected with MRI. Because of the difficulty of performing optimal ophthalmologic and neurologic examinations, especially in young children, cranial and orbital MRI should be considered to detect life-threatening pathologies.

Chromatic visual evoked potentials indicate early dysfunction of color processing in young patients with demyelinating disease

PURPOSE

Chromatic visual evoked potentials (cVEP) primarily reflect the parvocellular visual pathway function, which has been shown to be predominantly affected in demyelinating disease (DD). The purpose of this study was to evaluate cVEP responses and to compare them with other structural and functional findings in young patients with DD.

METHODS

Thirty patients (8-28 years of age) with DD with or without a history of optic neuritis (ON) were investigated. Twenty-five eyes had at least one episode of ON (ON-group) and 35 eyes had no clinically evident episode of ON (nON-group). OCT imaging was performed using a high-resolution spectral-domain OCT (SD-OCT), measuring retinal nerve fiber layer (RNFL) thickness. Pattern reversal electroretinography (PERG) and visual evoked potentials (VEP) were recorded according to the ISCEV standard, and chromatic visual evoked potentials (cVEP) were recorded to isoluminant red-green (R-G) and blue-yellow (B-Y) 7° circle stimuli, composed of horizontal sinusoidal gratings with spatial frequency 2 cycles/°, 90% chromatic contrast and onset-offset (300:700 ms) mode of stimulation. Structural and functional measures were analyzed and compared between the groups.

RESULTS

Both general (G) and temporal (T) RNFL thicknesses were reduced below normal limits in most of the eyes. However, in the ON-group (G: 77.5 ± 20.6, T: 51.4 ± 23.4 µm), the thinning was more significant (p < 0.001) than in the nON-group (G: 95.4 ± 12.1, T: 70.1 ± 11.5 µm). PERG N95 was within normal limits in the nON-group, while it was significantly more affected in the ON-group (7.4 ± 1.0 vs. 5.1 ± 2.0 μV; p < 0.0001). Similarly, also VEP P100 latency and amplitude showed a greater percentage of abnormality in the ON-group, the latency being longer (117.2 ± 16.9 vs. 99.4 ± 4.6 ms; p < 0.0001) and the amplitude lower (9.1 ± 5.1 vs. 16.4 ± 7.5 μV; p < 0.0001). The cVEP N-wave amplitude to R-G and B-Y stimuli was reduced below normal limits in both ON- and nON-groups; however, cVEP to B-Y stimulation were slightly more affected in the ON-group (4.0 ± 3.8 vs. 5.9 ± 3.3 µm; p = 0.02). A positive correlation between cVEP amplitude and RNFL thickness and between cVEP amplitude and PERG N95 amplitude, as well as a strong negative correlation between cVEP amplitude and P100 latency was observed.

CONCLUSIONS

These findings demonstrate that cVEP indicate early abnormality of parvocellular pathway function in eyes with or without a history of optic neuritis and can be used together with other structural and functional parameters to evaluate visual pathway integrity of young patients with DD.

Clinical Features and Visual Outcomes of Optic Neuritis in Chinese Children

Purpose. Although optic neuritis (ON) in children is relatively common, visual outcomes and factors associated with the condition have not been well documented. The aim of this study was to evaluate the clinical features and visual outcomes of ON in Chinese children. Methods. Patients with a first episode of ON at a tertiary neuroophthalmic centre in China were assessed and followed up for at least three months. Visual outcomes and clinical, laboratory, and neuroimaging findings were reviewed. In patients with bilateral ON, only the eyes with worse visual acuity (VA) at presentation were used for statistical analysis. Results. Seventy-six children (76 eyes) with a first episode of ON were included. The mean age was 11.8 years, 60.5% were females, and 48.7% had bilateral involvement. The children were followed up for an average of 18.5 months (age range, 3-48 months). Vision loss at presentation was severe, with VA < 20/200 in 37 eyes (48.7%). At the final visit, 3 (3.9%) eyes had VA of at least 20/20, and 41 (53.9%) eyes had VA of at least 20/40. The final VA in 35 eyes (46.1%) was worse than 20/40. Children aged ≤ 10 years had better predicted visual outcomes when compared to children over 10 years (odds ratio = 2.73, 95% confidential interval: 1.05-7.07, and P = 0.039). The other features of this cohort, such as sex, experienced bilateral attack, VA at presentation, presence of optic disc edema, systemic diseases, magnetic resonance imaging (MRI) findings, and aquaporin-4 (AQP-4) antibody status, were not significantly correlated with the final visual outcome. Conclusion. The data revealed the clinical characteristics and visual outcomes of ON in Chinese children. ON in children was associated with severe vision loss and relatively good visual recovery. The age at onset could predict the final visual function.

Acute onset blindness: a case of optic neuritis and review of childhood optic neuritis

Optic neuritis (ON) is an acquired disorder of the optic nerve due to inflammation, demyelination or degeneration. We report a child who presented with acute onset bilateral visual loss who, following a diagnosis of ON, was treated and had excellent visual recovery. Paediatric ON is considered to be different clinical entity to adult ON. Although in children ON is usually parainfectious or postinfectious, it can be the first presenting feature of multiple sclerosis or neuromyelitis optica spectrum disease. In this paper, we discuss the literature on treatment of ON and prediction of risk of recurrence.

Nationwide Incidence of Acquired Central Nervous System Demyelination in Icelandic Children

INTRODUCTION

Recognizing acquired demyelinating syndromes and multiple sclerosis is important to commence early treatment. The objective of this study was to describe the incidence of acquired demyelinating syndromes and multiple sclerosis among the entire Icelandic pediatric population according to recently promoted criteria.

PATIENTS AND METHODS

The study included all children in Iceland (<18 years) with acquired demyelinating syndromes and multiple sclerosis from 1990 to 2009 with a minimum of 5-year follow-up. Clinical data were gathered and radiological images reviewed. The cohort included all patients with acquired demyelinating syndromes and multiple sclerosis in the Icelandic pediatric population.

RESULTS

Eighteen patients with acquired demyelinating syndromes and multiple sclerosis were included, the total annual incidence being 1.15/100,000 (acquired demyelinating syndromes 1.02 and multiple sclerosis 0.45/100,000). The median age at diagnosis was 14.25 years (range 1.25-17.5 years). Thirteen patients were initially diagnosed with clinically isolated syndrome, two had acute disseminated encephalomyelitis, two had multiple sclerosis, and one had neuromyelitis optica. Seven children were diagnosed with multiple sclerosis; three patients with clinically isolated syndrome developed multiple sclerosis after the age of 18 and were not included in the multiple sclerosis group. The gender ratio was equal. Of the nine girls, seven were diagnosed with clinically isolated syndrome. Most patients (11 of 18) were diagnosed during the period January through March. Oligoclonal bands in cerebrospinal fluid were exclusively found in patients with multiple sclerosis and clinically isolated syndrome and 13 of 14 available magnetic resonance images revealed clear abnormalities.

CONCLUSION

The annual incidence of acquired demyelinating syndromes and multiple sclerosis in Iceland was 1.15/100,000 children. The risk of progression from clinically isolated syndrome to multiple sclerosis was high. There was no female preponderance.

Optic Neuritis in Korean Children: Low Risk of Subsequent Multiple Sclerosis

BACKGROUND

A relationship between optic neuritis and multiple sclerosis has previously been reported in non-Asian adults. We extended the investigation to Korean children.

OBJECTIVES

We compared the clinical features, laboratory findings, and visual outcomes of optic neuritis between prepubertal children and postpubertal adolescents and evaluated the conversion rate of optic neuritis to multiple sclerosis in Korean children.

METHODS

We conducted a retrospective analysis of children less than 18 years of age presenting with optic neuritis at Pusan National University Hospital between January 2002 and December 2013. Outcomes and clinical, ophthalmologic, magnetic resonance imaging, and laboratory findings were reviewed.

RESULTS

Twenty-six children (male:female, 1:1.2) were included. Follow-up duration was 16.3 ± 27.5 months in the prepubertal children (≤10 years, n = 13) and 8.2 ± 9.2 months in postpubertal adolescent (>10 years, n = 13) (P = 0.32). There was no significant difference between the prepubertal group and postpubertal group in clinical, ophthalmologic, magnetic resonance imaging, or laboratory findings. Of two patients (7.7%) with abnormal brain magnetic resonance images, one developed multiple sclerosis and the other developed acute disseminated encephalomyelitis. Of three patients (11.5%) with relapsing optic neuritis, two developed systemic lupus erythematosus and one developed multiple sclerosis.

CONCLUSION

The risk of developing multiple sclerosis after pediatric optic neuritis was low (7.7%). Abnormal brain magnetic resonance imaging and relapsing optic neuritis should alert the clinician to systemic or neurological disorders.

Oligoclonal bands predict multiple sclerosis in children with optic neuritis

We retrospectively evaluated predictors of conversion to multiple sclerosis (MS) in 357 children with isolated optic neuritis (ON) as a first demyelinating event who had a median follow-up of 4.0 years. Multiple Cox proportional-hazards regressions revealed abnormal cranial magnet resonance imaging (cMRI; hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 3.39-10.39, p < 0.001), presence of cerebrospinal fluid immunoglobulin G oligoclonal bands (OCB; HR = 3.69, 95% CI = 2.32-5.86, p < 0.001), and age (HR = 1.08 per year of age, 95% CI = 1.02-1.13, p = 0.003) as independent predictors of conversion, whereas sex and laterality (unilateral vs bilateral) had no influence. Combined cMRI and OCB positivity indicated a 26.84-fold higher HR for developing MS compared to double negativity (95% CI = 12.26-58.74, p < 0.001). Accordingly, cerebrospinal fluid analysis may supplement cMRI to determine the risk of MS in children with isolated ON.

The Role of HLA in MS Susceptibility and Phenotype

One of the most consistent findings in multiple sclerosis (MS) is that development of MS is linked with carriage of the class II human leucocyte antigen (HLA) molecule HLA-DRB1*15:01; around 60 % of Caucasian MS patients carry this allele compared to 25-30 % of ethnically matched healthy individuals. However, other HLA molecules have also been linked to the development of MS. In this chapter, the association between different HLA types and susceptibility to MS will be reviewed, and other linkages between the carriage of specific HLA molecules and clinical and experimental findings in MS will be considered.

Treatment of pediatric optic neuritis

OPINION STATEMENT

Pediatric optic neuritis is a rare disorder causing a subacute loss of vision (often bilateral) in children, often of a severe degree. Common clinical findings include dense visual field loss, afferent pupillary defect (APD) in unilateral cases, and papillitis that is often bilateral. Contrary to optic neuritis in the adult population, the differential diagnosis for this disorder in pediatric patients is quite extensive, so neuroimaging and serologic evaluation are necessary to exclude an infectious or neoplastic process. Pediatric optic neuritis may occur as a clinically isolated syndrome, or in association with diffuse neurologic dysfunction, such as acute disseminated encephalomyelitis (ADEM). Optic neuritis may also be the first episode heralding the onset of pediatric multiple sclerosis or neuromyelitis optica (NMO or Devic's disease). Therefore, formal neurologic evaluation and follow-up are indicated. Although the management of this disorder in adults is well described, there is a paucity of evidence-based, prospective clinical data on its management and treatment in a pediatric population. The current treatment of pediatric optic neuritis consists of 3 to 5 days of intravenous methylprednisolone (4-30 mg/kg per day), followed by a prolonged oral corticosteroid taper. A prolonged course of oral steroid (2-4 weeks) is recommended to avoid recurrence, which is common in this age group. Some controversy persists concerning the exposure of children to high-dose parenteral corticosteroids to treat an entity that is usually self-limited, but given the severity of vision loss in one or both eyes in this population, this intervention is standard in neuro-ophthalmologic practice.

Clinical profile of Malay children with optic neuritis

Limited data are available on optic neuritis in Asian children. Clinical profiles tend to vary with different races. We aimed to determine the clinical manifestations, visual outcomes, and etiologies of optic neuritis in Malaysian children, and discuss the literature of optic neuritis in Asian children. A retrospective study involving 14 children with optic neuritis was performed at Hospital Universiti Sains Malaysia between July 2005 and January 2010 (follow-up, 18-60 months). Clinical features, laboratory results, possible etiologies, and visual acuity after 1 year were studied. Females were predominant (mean age at presentation, 11.1 years). All patients manifested bilateral involvement. Swollen optic discs were observed in 92.9% of eyes; 60.7% of patients demonstrated a visual acuity of 6/60 (or 20/200) or worse on presentation, whereas 14.3% remained at 6/60 (or 20/200) or worse, 1 year after their attack. Cecocentral scotoma comprised the most common visual field defect. Infection contributed to 50.0% of cases; 14.3% progressed to multiple sclerosis during follow-up, with no evidence of recurrent optic neuritis. The clinical profiles and etiologies of optic neuritis in Malay children differ slightly compared with other optic neuritis studies of Asian children. The frequency of progression to multiple sclerosis is relatively lower.

Pediatric optic neuritis and risk of multiple sclerosis: meta-analysis of observational studies

PURPOSE

To determine the relationships among age, unilateral versus bilateral simultaneous presentation, magnetic resonance imaging (MRI) lesions, and the risk of multiple sclerosis (MS) in children with optic neuritis.

METHODS

A systematic literature review and meta-analysis were performed by the use of a MEDLINE search to identify published studies containing individual patient data for children with optic neuritis. Age, laterality (unilateral vs bilateral simultaneous optic neuritis), presence of brain MRI abnormalities, and development of MS were recorded. Logistic regression was used to determine the relationships among these parameters.

RESULTS

Fourteen studies met inclusion criteria. Data for 223 patients (age range 2-17.8 years) were analyzed. Unilateral optic neuritis occurred more frequently in older children but was not associated with an increased risk of MS, after adjusting for age (odds ratio [OR] = 1.9, P = 0.11; 95% confidence interval [CI], 0.9-4.3). For every 1-year increase in age, the odds of developing MS increased by 32% (OR = 1.3, P = 0.005; 95% CI, 1.1-1.6, adjusted for the presence of MRI lesions). The risk of MS was greater in children with abnormal brain MRI scans at presentation compared with normal MRIs (OR = 28.0, P < 0.001, 95% CI, 6.3-125.1, adjusted for age).

CONCLUSIONS

The relationship between unilateral and bilateral optic neuritis and the development of MS is dependent on age. Older children and those with brain MRI abnormalities at presentation, are at greater risk for MS. Long-term follow-up of children with optic neuritis is needed to establish the true risk for the development of MS.

Clinical characteristics of optic neuritis in Taiwanese children

PURPOSE

To document the etiology, clinical presentation, and visual prognosis of optic neuritis in Taiwanese children.

METHODS

Retrospectively reviewed children younger than 18 years old with optic neuritis in Chang Gung Memorial Hospital and Chang Gung Children's Hospital from 1998 to 2009.

RESULTS

There were 24 children (38 eyes) with optic neuritis in that period. Overall, 14 patients (58.3%) were female and 10 patients (41.7%) were male. In total, 14 patients (58.3%) had bilateral involvement, and 10 patients (41.7%) had unilateral involvement. Out of 38 eyes, 24 (63.2%) had disc swelling. Out of 24 patients, 21 (87.5%) underwent intravenous steroid therapy (10 to 30 mg/kg/day) for 3-5 days, and followed by an oral taper. Out of 24 patients, 20 (83.3%) achieved final visual acuity (VA) of 20/40 or better. However, a poor visual outcome (four patients) (VA<20/40) was correlated with pale disc at presentation (P=0.002, Pearson χ (2)-test) and age older than 10 years (P=0.012, Fisher's exact test). Five patients were diagnosed with acute disseminated encephalomyelitis (ADEM) (21%), and three patients were diagnosed with multiple sclerosis (MS) (12.5%). Patients with ADEM did not have a better visual outcome than patients with MS (P=0.643, Fisher's exact test).

CONCLUSIONS

Visual recovery from optic neuritis was favorable in Taiwanese children. A poor visual outcome was correlated with pale disc at presentation and patients' age older than 10 years. ADEM is the most common associated systemic disease; MS is relatively rare.

Pediatric multiple sclerosis

BACKGROUND

Pediatric multiple sclerosis (MS), once considered a rare childhood illness, has been increasingly identified as an important childhood acquired neurologic disease requiring early recognition and intervention.

SUMMARY

We present a comprehensive review of the current terminology of acquired central nervous system demyelination in children, pertinent investigations, including magnetic resonance imaging and cerebrospinal fluid cerebrospinal fluid studies, and an approach to the differential diagnosis of pediatric onset MS. In addition, the recent studies exploring the epidemiology and pathobiology will be discussed. Finally, we present an algorithm for the treatment of episodes of demyelination along with chronic immunomodulatory therapeutic options in this patient population.

CONCLUSIONS

Although some similarities exist to adult onset MS, MS onset during childhood and adolescence presents unique diagnostic challenges and requires specialized multidisciplinary care for optimal management. National and international collaborative studies are underway to aid in the understanding of the early and ongoing pathogenesis of MS.

Childhood optic neuritis: the pediatric neurologist's perspective

BACKGROUND

Optic neuritis in children may be an isolated, usually postinfectious event, or the symptom of a more widespread disorder.

AIM

To investigate the etiological spectrum of optic neuritis in children in association with diagnostic findings and follow-up results.

METHODS

We retrospectively examined the records of 31 children aged 4-15 (mean 9.7+/-2.9) years in whom isolated optic neuritis was the presenting neurological symptom.

RESULTS

Monophasic bilateral optic neuritis was the most common presentation (45%), followed by the unilateral (32%) and recurrent (22%) forms. Initial cranial MRI was abnormal in 12/31 patients. During a mean follow-up of 2.2 years (6 months-15 years), 6/14 bilateral cases, 9/10 unilateral and 5/7 recurrent cases were diagnosed with various disorders including total eight with MS. The MS group tended to start with unilateral optic neuritis, was older (mean 11.6+/-1.5 vs. 8.8+/-2.9 years), and included more girls than the other groups.

CONCLUSIONS

Optic neuritis in children is frequently part of a systemic or neurological disorder even in the presence of normal cranial imaging. These patients should be evaluated and followed-up in pediatric neurology clinics.

Demyelinating optic neuritis in children

Acute demyelinating optic neuritis in children can occur in isolation or be associated with acute disseminated encephalomyelitis, multiple sclerosis, or neuromyelitis optica. Clinical features, neuroimaging, cerebrospinal fluid findings, and long-term prognosis were reviewed in 26 children diagnosed with optic neuritis at the first presentation of demyelinating disease. The risk factors for the subsequent diagnosis of multiple sclerosis were analyzed. The mean duration of follow-up was 6.2 years. To date, 6 children have been diagnosed with multiple sclerosis (23%). An abnormal brain magnetic resonance imaging, older age, oligoclonal bands in cerebrospinal fluid, and elevated immunoglobulin G index were associated with multiple sclerosis outcome. Children with monosymptomatic optic neuritis and an abnormal brain magnetic resonance imaging had a higher risk for multiple sclerosis. These children should be monitored closely for the subsequent diagnosis of multiple sclerosis and can be considered for early preventive therapy.

Clinical characteristics of multiple sclerosis and associated optic neuritis in Korean children

PURPOSE

To study the clinical characteristics of multiple sclerosis and associated optic neuritis in Korean children.

METHOD

A retrospective analysis was performed on 10 patients with an onset of multiple sclerosis before age 16. Information on sex, age of onset, clinical course, laboratory findings, and clinical characteristics of optic neuritis was obtained.

RESULT

The mean age at presentation was 7.31 +/- 2.99 years, and the mean duration of observation was 36.2 +/- 26.1 months. No female predilection (50%) was observed. The disease presented as relapsing-remitting type multiple sclerosis in all patients and transited to secondary progressive type in two cases (20%). No oligoclonal bands were found in any patient. Optic neuritis occurred in eight patients (80%); five (62.5%) of these had optic neuritis at the first multiple sclerosis attack, with all five manifesting bilateral simultaneous optic neuritis. Visual acuity recovered to > or =20/40 in 8 of 15 eyes (53.3%), but in 2 eyes (13.3%) visual acuity remained at < or =20/200. In the patients with optic neuritis, the patients who showed optic neuritis at initial presentation had a worse visual prognosis (p = 0.030, Mann-Whitney U-test).

CONCLUSIONS

In Korean children with multiple sclerosis, age of onset was younger than reported in other countries, and there was no female predominance. The prognosis for good visual acuity was worse in patients who initially presented with optic neuritis.

Optic neuritis in adults and children

Most ophthalmologists will encounter optic neuritis in the course of their practice. The disease behaves very differently in children versus adults. The ONTT and CHAMPS trials have given us important data regarding prognosis and management in adults, including probability of developing MS. Optic neuritis in children, while less common, must be considered in the differential diagnosis of subacute visual loss, especially in children with bilateral impairment. Secondary causes of optic neuritis are more common in children and an investigation should be performed to assess for associated disease states. In both populations, the ophthalmologist will play a central role in the diagnosis, treatment, and management of these patients, whether it is an isolated case of optic neuritis or the initial presentation of a long-term struggle with MS. With the advent of immunomodulating therapy to minimize both the subsequent incidence and severity of MS, early diagnosis and appropriate management by the ophthalmologist has become even more critical.

Pediatric multiple sclerosis

The onset of multiple sclerosis (MS) in childhood is being increasingly recognized. Despite this, there currently exist several barriers to the prompt diagnosis of MS in children. Many clinicians view MS as an exclusively adult-onset disease, and thus they may not entertain the diagnosis in a child. Also, the clinical and radiographic criteria for the diagnosis of MS have not been validated in a pediatric MS population. The available literature, as well as experience gained in a dedicated pediatric MS clinic, is used here to describe features of pediatric MS and contrast these with adult MS. The rationale and importance of future studies in pediatric MS is highlighted.

Clinical characteristics of Japanese children with optic neuritis

The clinical characteristics of children with optic neuritis have been reported to be different from that of adults and to vary among different races. To determine the clinical characteristics of Japanese children with optic neuritis, we examined the medical records of 41 children who were diagnosed with optic neuritis at the Department of Ophthalmology of Chiba University Hospital between January 1979 and December 2001. Information on the sex, age of onset, laterality, initial visual acuity, final visual acuity, recent infections and immunizations, and presence of systemic neurologic diseases, such as multiple sclerosis or acute disseminated encephalomyelitis, was obtained. These findings revealed that the clinical features of optic neuritis in children were similar to those reported earlier. The percentage of optic neuritis cases that developed multiple sclerosis in children was similar to that for children in Europe and North America, and this percentage was not lower than that in adults in our clinic. These findings can be taken as the characteristics of optic neuritis of children in Japan.

Childhood autoimmune neurologic diseases of the central nervous system

An autoimmune mechanism for ADEM and MS can be supported by the similar patterns of pathologic changes seen in both diseases with the animal model EAE induced by inoculating animals with nervous tissue and the occurrence of ADEM in patients exposed to nervous tissue during vaccination. Whereas there are no universally agreed-upon criteria for the diagnosis of ADEM, a combination of prodromal illness or preceding vaccination, MRI signs of demyelination, and an acute presentation of neurologic symptoms are the triad most commonly looked for in making the diagnosis of ADEM. An ever-increasing number of infections and vaccinations (nonspecific URIs being most common) has been associated with ADEM. Fever and encephalopathy are seen frequently at presentation. Seizures also are common, as are cranial nerve abnormalities and motor symptoms. A mild pleocytosis or protein elevation is found in the majority of patients with ADEM. Intrathecal IgG synthesis and oligoclonal bands are relatively infrequent but should not be considered inconsistent with the diagnosis of ADEM. White matter changes on T2 in a bilateral although asymmetric distribution with relative sparing of the periventricular region with or without deep gray matter involvement is consistent and to some a requirement for the diagnosis. Low-dose steroids have no beneficial effect in the treatment of ADEM and may be contraindicated. High-dose steroids may have a beneficial effect, particularly in more prolonged illnesses, although the evidence is primarily anecdotal. If steroids are used to improve morbidity, 30 mg/kg/d of methylprednisolone for three to five days is the dose with a six-week taper to reduce the risk of recurrence. The prodromal infection may be a major factor in the ultimate mortality and morbidity of the disease. The current mortality of ADEM is quite low. Whether or not this is an effect of different triggering agents or changes in medical care cannot be determined. In larger series of patients with ADEM, 10% to 20% of children experience some sort of recurrence with the majority occurring in the initial one to two months after the first event. This is sometimes associated with steroid withdrawal. A second group of children have a late second recurrence that clinically may not be MS but a recurrence of ADEM, although longer follow-up may change that assessment. Two months should be allowed before a second relapse is considered a manifestation of MS, whereas a second attack also may occur years after an initial attack of ADEM and still be consistent with ADEM recurrence. MS does occur during childhood, with the youngest children at the least risk, and risk increasing with age. The criteria of Poser et al can be used to diagnose MS in childhood [40]. The presentation of MS in childhood is most often sensory, motor, and brainstem signs and symptoms. A relapsing-remitting course is most common with a first relapse occurring in the year after presentation. MRI findings in MS typically show periventricular changes. Oligoclonal bands and CSF IgG synthesis are found in the majority. Treatments of childhood MS have not been studied adequately, but, when treatments studied in adults are used in children, they are well tolerated. Efficacy has not been shown. The long-term outcome of MS in childhood can be either severe or benign with no clear consensus that childhood MS is either a less or more severe disease than the adult form. ATM and ON treatments and outcomes are particularly difficult to evaluate because of the heterogeneity of populations included in case series and the small numbers reported. Steroids are used with anecdotal reports of their superiority to nontreatment. Outcome in ATM often can be poor, whereas in ON it rarely is. A multinational collaborative effort to study and collect the large numbers necessary to address the important questions in these childhood autoimmune disorders would be of great benefit and the only way likely to demonstrate good evidenced-based medicine practiced in this field.

Prospective study of multiple sclerosis with early onset

Fifty-four subjects (36 females and 18 males) affected by clinically definite multiple sclerosis (MS) and with onset of the disease at 15 years of age or before were prospectively studied in five Italian MS centres. Female/male ratio was 4.7 in subjects with age > or = 12 years, suggesting a role of hormonal changes in triggering MS onset The mean follow-up duration was 10.9+/-5.6 years. The functional systems more frequently involved at onset were the pyramidal and brainstem (both in 28% of cases). The onset was monosymptomatic in 31 subjects (57%). The course was relapsing-remitting in 39 subjects (72%) and relapsing-progressive in 15 (28%). Disability was assessed by the Expanded Disability Status Scale (EDSS): the mean score after 8 years of follow up was 3.5 (+/-2.5). The score was <4 in 68% of cases, between 4 and 6 in 8% of cases, >6 in 24% of cases. Disability after 8 years was highly predicted by disability in the first year (p=0.008). There was a tendency to a worse prognosis in relation to the number of relapses in the first 2 years (p=0.08). The outcome was not influenced by the characteristics of symptoms at onset age and gender.

Optic neuritis in Asian children

PURPOSE

To study the clinical spectrum of pediatric optic neuritis in Korean children.

METHODS

A retrospective analysis was performed on 23 patients with onset of the disease before the age of 16 years from 1995 to 2000. The degree of initial visual loss, subsequent visual recovery, magnetic resonance images, and associated diseases was reviewed.

RESULTS

There was no female predilection in the study group (43%) with a mean age of 8.9 years at presentation. Involvement was bilateral in 87% of patients. A preceding febrile illness within 2 weeks of visual symptoms was reported in 39% of patients. Of the 43 involved eyes of 23 patients, disc swelling was present in 51%, and central/cecocentral scotoma in 58% of the involved eyes. With a mean follow-up of 14 months, 79% of the patients had final vision of > or =20/40. Twenty-four (96%) of 25 eyes with intravenous steroid treatment and 10 (56%) of 18 eyes without intravenous steroids showed final visual acuity > or =20/40. Only 1 patient (4%) with multifocal signal abnormalities around the periventricular white matter developed multiple sclerosis.

CONCLUSION

Korean children with optic neuritis showed bilateral involvement with papillitis. The visual prognosis was relatively good and especially better in the patients receiving intravenous steroid treatment than in those without any treatment; however, this study is not controlled. Although a longer follow-up period is required, the development of multiple sclerosis is rare in Korean children with optic neuritis.

Multiple sclerosis in childhood and adolescence: clinical features and management

The presentation of multiple sclerosis (MS) in childhood has traditionally been thought to be rare. However, more paediatric cases are now being reported, as a result of progress in diagnostic techniques with the use of sensitive imaging modalities of the brain and spinal cord. Management from an early age and the availability of new treatment options have changed the outcome of paediatric MS. Drugs currently available for treatment, such as beta-interferons, copolymer-1 and intravenous immunoglobulin G, have been found to reduce relapse rate, disease severity and progression to disability in adults, but have not been investigated in children and adolescents. The overall outcome of MS in children is apparently no worse than in adults and the disease may even be less aggressive in children. In juvenile MS, disease progression does not appear to be related to age of onset, severity of neurological involvement or mono/polysymptomatic involvement at presentation. The potential to treat MS has significantly changed the prognosis. Early diagnosis is important, as early treatment can prevent or delay the development of disability.

Ophthalmology update for primary practitioners. Part I. Update on optic neuritis

Optic neuritis is a common cause of acute visual loss. It is typified by sudden onset of visual impairment and pain with eye movements, followed by spontaneous recovery of vision over several months. Pathologically, optic neuritis is an acute demyelinating event affecting the optic nerve. Objective physical findings are typically few, including an afferent pupillary defect or Marcus-Gunn pupil, whereas subjective psychophysical findings abound (ie, diminished central visual acuity, color vision, decreased contrast sensitivity, and visual field abnormalities). These characteristics have made the diagnosis of optic neuritis based solely on clinical grounds disquieting to practitioner and patient alike. In addition, the fact that optic neuritis is often associated with multiple sclerosis as the first clinical manifestation of disease gives further reason for both patient and physician anxiety. The serious nature of visual loss and the consequences of making the diagnosis of optic neuritis has given rise to extensive testing and expensive treatments. This review is intended to explore our current state of knowledge with regard to (1) clinical presentation, (2) ancillary testing, (3) therapeutic intervention, and (4) associated disease, specifically the risk for multiple sclerosis in the patient who presents with an acute optic neuritis. Finally, a suggestion guide for informing the patient and addressing his or her concerns will be presented.

Multiple sclerosis, acute disseminated encephalomyelitis, and related conditions

Multiple sclerosis (MS) and acute disseminated encephalomyelitis (ADEM) are conditions whose closely related pathology suggests shared pathophysiological elements, but whose clinical courses are usually, but not always quite dissimilar. The former is largely a disease of adulthood, the latter of childhood. Optic neuritis, demyelinative transverse myelitis, and Devic's syndrome are neurological syndromes that may occur as manifestations of either MS or ADEM. Patients with Miller-Fisher syndrome and encephalomyelradiculoneuropathy usually have features suggesting ADEM in combination with acute demyelinative polyneuropathy. These various conditions and other forms of ADEM share an indistinct border with encephalitides, granulomatous, and vasculitic conditions. MS, ADEM, and the pertinent syndromic subtypes, their differential diagnosis, treatment, and prognosis are considered in this review. Acute cerebellar ataxia is a syndrome that is likely to be pathophysiologically distinct from ADEM, although its occurrence as a postinfectious illness suggests a distant kinship. It is also reviewed.

Age dependence of clinical and pathological manifestations of autoimmune demyelination. Implications for multiple sclerosis

A prominent feature of the clinical spectrum of multiple sclerosis (MS) is its high incidence of onset in the third decade of life and the relative rarity of clinical manifestations during childhood and adolescence, features suggestive of age-related restriction of clinical expression. Experimental allergic encephalomyelitis (EAE), a model of central nervous system (CNS) autoimmune demyelination with many similarities to MS, has a uniform rapid onset and a high incidence of clinical and pathological disease in adult (mature) animals. Like MS, EAE is most commonly seen and studied in female adults. In this study, age-related resistance to clinical EAE has been examined with the adoptive transfer model of EAE in SJL mice that received myelin basic protein-sensitized cells from animals 10 days (sucklings) to 12 weeks (young adults) of age. A variable delay before expression of clinical EAE was observed between the different age groups. The preclinical period was longest in the younger (<14 days of age) animals, and shortest in animals 6 to 8 weeks old at time of transfer. Young animals initially resistant to EAE eventually expressed well-developed clinical signs by 6 to 7 weeks of age. This was followed by a remitting, relapsing clinical course. For each age at time of sensitization, increased susceptibility of females compared to males was observed. Examination of the CNS of younger animal groups during the preclinical period showed lesions of acute EAE. Older age groups developed onset of signs coincident with acute CNS lesions. This age-related resistance to clinical EAE in developing mice is reminiscent of an age-related characteristic of MS previously difficult to study in vivo. The associated subclinical CNS pathology and age-related immune functions found in young animals may be relevant to the increasing clinical expression of MS with maturation, and may allow study of factors associated with the known occasional poor correlation of CNS inflammation and demyelination and clinical changes in this disease.

Optic neuritis in children: clinical features and visual outcome

BACKGROUND

The purpose of this paper is to study the clinical spectrum of pediatric optic neuritis. We evaluated the presenting features, neuroimaging findings, cerebrospinal fluid abnormalities, associated systemic disease, and visual outcome in patients with this condition.

METHODS

A retrospective analysis was performed on all patients who came to Baylor College of Medicine with optic neuritis during a 6-year period from 1991 to 1997. The degree of initial visual loss, subsequent visual recovery, and associated disease were reviewed. Magnetic resonance images and cerebrospinal fluid findings were also analyzed.

RESULTS

Twenty-five patients (39 eyes) 21 months of age to 18 years of age were included in the study, with a mean follow-up of 11 months. Fourteen patients (56%) had bilateral optic neuritis, and 11 patients (44%) had unilateral disease. Thirty-three of 39 eyes (84%) had visual acuity of 20/200 or less at presentation. Twenty-one of 25 patients (84%) were given intravenous methylprednisolone (10 to 30 mg/kg/day). Thirty of 39 eyes (76%) recovered 20/40 visual acuity or better. Three of 39 eyes (7%) recovered vision in the 20/50 to 20/100 range. Six of 39 eyes (15%) recovered vision of 20/200 or less. Twenty-three of 25 patients (92%) underwent magnetic resonance imaging of the brain. A normal magnetic resonance image of the brain was associated with recovery of 20/40 or better visual acuity in 6 of 6 affected eyes (100%). Seven patients were 6 years of age or younger at presentation. Six of 7 (85%) had bilateral disease, and 12 of 13 (92%) affected eyes recovered 20/40 visual acuity or better. Eighteen patients were 7 years of age or older at presentation. Eight of 18 (44%) had bilateral disease, and 10 of 18 patients (56%) had unilateral disease. Eighteen of 26 affected eyes (50%) recovered 20/40 visual acuity or better.

CONCLUSION

Pediatric optic neuritis is usually associated with visual recovery; however, a significant number (22%) remain visually disabled. A normal magnetic resonance image of the brain may be associated with a better outcome. Younger patients are more likely to have bilateral disease and a better visual prognosis.

Promotion of endogenous remyelination in multiple sclerosis

Studies in both human and experimental models demonstrate that myelin repair occurs in the central nervous system and is a normal physiologic response to myelin injury. However, remyelination in MS is often incomplete and limited. The outcome of an actively demyelinating lesion depends on the balance between factors promoting myelin destruction and myelin repair. Experimental models of CNS demyelination provide an opportunity to investigate the morphologic, cellular and molecular mechanisms involved in remyelination. This review focuses on experiments using the Theiler's virus model of demylination which indicate that manipulation of the immune response has the potential to promote endogenous CNS remyelination and functional recovery in MS.

Primary CNS demyelinating diseases in childhood: multiple sclerosis

We report on five children (three female and two male, age span 11-16 years) with laboratory-supported definite multiple sclerosis or clinically definite multiple sclerosis, diagnosed on the basis of Poser and Paty criteria. All patients were subjected to serial clinical examinations, magnetic resonance investigations, CSF biochemical and immunological studies, and neurophysiological and neuropsychological assessments. Four of the five examined subjects underwent steroid treatment. Over a period of 3 years relapses have been observed in three of them. The first symptoms and signs of multiple sclerosis may be subtle and misleading; careful assessment of them may be crucial for an early diagnosis of the disease.

Availability of frequency-selective fat-saturation pulse (Fat-Sat) MRI in childhood optic neuritis

A 2-year-old boy with acute optic neuritis, confirmed by gadolinium-DTPA enhancement of the optic nerve using frequency-selective fat-saturation pulse magnetic resonance imaging (Fat-Sat MRI), is reported. Because it is difficult in very young children to sufficiently evaluate visual acuity, visual field, and retroocular pain on eye movement, and visual evoked potential during wakefulness, Fat-Sat MRI will be useful for revealing optic nerve inflammation and for monitoring treatment.

Optic neuritis in children: recurrence and subsequent development of multiple sclerosis

Recurrent optic neuritis and the subsequent development of multiple sclerosis in children, particularly in Asian countries, are not well known. We report on recurrent optic neuritis and subsequent multiple sclerosis in 22 Thai children who were younger than 15 years of age at the onset of optic neuritis, had no previous neurologic illness, and were monitored for 6-20 years. Improvement of vision was observed in 8, 10, and 2 patients after the first, second, and third week of onset, respectively. Two patients had recurrent optic neuritis and the other 2 patients subsequently developed clinical definite multiple sclerosis characterized by hemiparesis at 6 months and myelopathy at 2 years later in 1 patient and myelopathy and brainstem dysfunction in the other at 4 and 6 years later. The frequency of subsequent development of multiple sclerosis after optic neuritis may be similar to that reported from the United States and European countries.

Pediatric multiple sclerosis report of 14 cases

We present clinical data from 14 multiple sclerosis (MS) patients who have been admitted to our hospital between January 1980 and May 1992, whose age of onset ranged from 2-15 years. Our patients could be classified as having a clinically definite form of the disease. Initial symptoms varied from minor, such as motor or sensory impairment, bladder dysfunction, to the worst clinical presentation, suggesting diffuse encephalopathy. All the patients had a relapsing-remitting course. We report the paraclinical and laboratory examinations that were done in these patients. Over the period 1980 to 1992 these patients had 39 attacks. CSF analysis was performed in the phase of activity of the disease on 23 occasions and was normal in 12. At least one brain CT scan was performed in 9 patients and showed white matter abnormalities in 6. Cranial magnetic resonance imaging was done in 6 patients and were abnormal in 5. Visual evoked potential (EP) was abnormal in 7 of 8 patients; brainstem acoustic EP was abnormal in 4 of 8 patients and somatosensory EP in 4 of 8. MS is not so rare in childhood and although its diagnosis is essentially a clinical one, paraclinical investigations are of great value in the identification of demyelinating disorders in childhood.

Optic neuritis in children with poor recovery of vision

We reviewed the records of 10 children with optic neuritis in whom recovery of vision was poor or incomplete. Our cases were otherwise similar to those described in previous studies in that they were always bilateral, often accompanied by a viral prodrome (seven of 10), and usually associated with disc oedema (seven of 10). Seven of twenty eyes had a final visual acuity of 6/60 or worse and only one patient regained 6/6 vision in either eye. In three patients the best vision in either eye was 6/60 or worse. Recovery of vision was often slow, taking up to six years. Five of 10 patients have developed multiple sclerosis (MS), and one child had acute disseminated encephalomyelitis (ADEM) with optic neuritis. Optic neuritis in children does not always carry a good prognosis for recovery of vision; however, the failure of vision recovery in a short period of time does not necessarily indicate a poor outcome. Some children with optic neuritis develop MS, which can develop even when optic neuritis follows a viral illness.

Bilateral visual loss in a child with disc swelling

A nine-year-old girl developed periorbital pain followed by sequential visual loss over a 3-day period. The patient recovered vision to a 20/40 level over a 5-month period of time. The differential diagnosis and evaluation in this presentation is discussed. The patient is believed to have had an idiopathic or parainfectious optic neuritis.

Multiple sclerosis in childhood: report of 15 cases

We report the preliminary results of an ongoing study of multiple sclerosis (MS) in childhood. The investigations include an analysis of the clinical picture and course. Multiple sclerosis in early childhood may present atypically, with a symptomatology suggesting diffuse encephalomyelitis, meningeal reaction, brain oedema, seizures, impaired consciousness and in some cases take a lethal course. Imaging studies including MRI and MR-spectroscopy, CSF-analysis, electrophysiology (VEP, BAEP, SER), and virological and immunological investigations are performed. So far 15 children have been studied. Their age at the onset of the disease ranged from 3 to 15 years. Abnormal CSF-findings with pleocytosis and oligoclonal IgG bands were present in 11 and 10 out of 15 patients respectively. MRI revealed numerous white matter lesions in the brain stem and cerebral hemispheres. VEP, BAEP and SER's were abnormal in most children. Proton magnetic resonance spectra from plaques exhibited a 50-80% decrease in N-acetyl aspartate, which is a potential marker of vital neuronal tissue, a decrease of the creatine pool and an increase of choline-containing compounds. Lactate was not increased. Our observations of MS in early childhood cast doubt on some of the previous notions concerning a latency period of several years between the exposure to a still unknown agent and the manifestation of MS. In view of atypical features in the initial phase, it would seem desirable to record cases of encephalomyelitis of undetermined origin as potential cases of MS and to register the further course for verification or exclusion.

Retrobulbar optic neuritis in a two-year-old boy

We report a 2-year-4-month-old boy with retrobulbar optic neuritis. He had a sudden onset of impaired vision, which progressed to total blindness within a day. The visual evoked potential (VEP) showed no activity, but the electroretinogram was normal. Computed tomography (CT) and magnetic resonance imaging (MRI) showed no abnormal findings in the visual tract. The cerebrospinal fluid (CSF) myelin basic protein (MBP) level was elevated and serum anti-myelin antibody was positive. These findings suggested that optic neuritis in our patient was induced by retrobulbar demyelination, perhaps as a result of an autoimmune process. His visual impairment recovered gradually, but not completely, following oral prednisolone therapy. We have followed him for one year since discharge and have found neither recurrence of optic neuritis nor any other neurological disorders. Optic neuritis in children is rare and, to our knowledge, this patient is one of the youngest to be reported. This case suggests that autoimmune mechanisms may induce optic neuritis even in early childhood. In addition to VEP and MRI studies, the CSF MBP and serum anti-myelin antibody can be useful in the diagnosis and follow-up the patients with optic neuritis.

The role of infection and vaccination in the genesis of optic neuritis and multiple sclerosis in children

This article describes the association between previous infection and/or vaccination and the development of optic neuritis (ON) in 18 children. Ten of these children subsequently developed clinically definite multiple sclerosis (MS), while in 8 patients a clinically definite etiology could not be confirmed. Vaccination preceded the first ON attack in 6 patients, all but one of whom subsequently developed MS. It also preceded subsequent demyelinating events in 6 patients. Ten of the patients had a bacterial or viral infection within the 2 weeks prior to the first symptoms of ON. Intrathecal antibody synthesis against 2 or more viruses could be shown in 5 out of 8 patients studied; 5 out of 6 patients had oligoclonal antibodies in CSF and 12 out of 16 patients a high IgG index. Neither intrathecal antibody synthesis against 2 or more viruses nor elevated IgG indexes could be found in the control patients. Measles and mumps occurred at a significantly later age in the children who subsequently developed MS than in the control children, and these patients had significantly more events that might have impaired the blood-brain barrier than the controls. These results indicate that immunological events leading to MS may be triggered during childhood. Vaccination and infection often precede ON in childhood. Intrathecal viral antibody production can occur already in childhood at the time of the first symptoms of MS.