Diagnosis, treatment, and outcomes of infantile spasms in the Trisomy 21 population

A Retrospective Cohort Study of Combined Therapy in West Syndrome associated with Trisomy 21

Background: West syndrome (WS) is a frequent epileptic encephalopathy associated with Down syndrome (DS). This study evaluated an outpatient protocol for WS in patients with DS who received vigabatrin (VGB) or VGB plus adrenocorticotrophic hormone. Methods: We analyzed infants treated in two neuropediatric centers from 2001-2021. We reviewed perinatal and familial history of epilepsy, spasm onset, treatment lag, electroencephalogram, neuroimaging, progression to epilepsy, and other neurological conditions. The outcomes were electroclinical resolution (ECR), relapses, and epilepsy progression. Results: Nineteen infants were included; 57.8% were male. The average spasm onset, follow-up, and treatment lag were 6.4 months, 8.15 years, and 2.33 months, respectively. Almost 74% had ECR after protocol intervention and minor epilepsy progression. Relapses occurred during combined therapy. Conclusions: The treatment protocol, especially combined therapy, was effective for WS in DS, impacting epilepsy progression and indicating the effectiveness of combined therapy to treat WS in patients with trisomy 21.

Response to treatment and outcomes of infantile spasms in Down syndrome

AIM

To estimate the prevalence, and evaluate presentation, treatment response, treatment side effects, and long-term seizure outcomes in all known cases of children with Down syndrome and infantile spasms on the island of Ireland.

METHOD

This was a 10-year retrospective multicentre review of clinical records and investigations, focusing on treatment response, side effects, and long-term outcomes.

RESULTS

The prevalence of infantile spasms in Down syndrome was 3.0% during the study period. Fifty-four infants were identified with median age of spasm onset at 201 days (interquartile range [IQR] 156-242). Spasm cessation was achieved in 88% (n=46) at a median of 110 days (IQR 5-66). The most common first-line medications were prednisolone (n=20, 37%), vigabatrin (n=18, 33.3%), and sodium valproate (n=9, 16.7%). At follow-up (median age 23.7mo; IQR 13.4-40.6), 25% had ongoing seizures and 85% had developmental concerns. Treatment within 60 days did not correlate with spasm cessation. Seventeen children (31%) experienced medication side effects, with vigabatrin accounting for 52%.

INTERPRETATION

Prednisolone is an effective and well-tolerated medication for treating infantile spasms in Down syndrome. Despite the high percentage of spasm cessation, developmental concerns and ongoing seizures were common.

Children With Trisomy 21 and Lennox-Gastaut Syndrome With Predominant Myoclonic Seizures

INTRODUCTION

Lennox-Gastaut syndrome is a severe form of pediatric epilepsy that is classically defined by a triad of drug-resistant seizures, including atonic, tonic, and atypical absence seizures; slow spike-and-wave discharges and paroxysmal fast activity on electroencephalography (EEG); and cognitive and behavioral dysfunction. In the vast majority, Lennox-Gastaut syndrome develops in patients with an identified etiology, including genetic or structural brain abnormalities. Long-term prognosis is generally poor with progressive intellectual deterioration and persistent seizures. At present, there are few reported cases of Lennox-Gastaut syndrome and trisomy 21 in the literature. To further delineate the spectrum of epilepsy in trisomy 21, we reviewed children with trisomy 21 and Lennox-Gastaut syndrome at one center over 28 years.

METHODS

This is a retrospective case series. At our institution, all EEG results are entered into a database, which was queried for patients with trisomy 21 from 1992 to 2019. Pertinent electroclinical data was obtained from medical records.

RESULTS

Of 63 patients with trisomy 21 and epilepsy, 6 (10%) had Lennox-Gastaut syndrome and were included in the study. Four of the 6 patients were male and 5 of 6 had neuroimaging, which was normal. Follow-up ranged from 3 to 20 years. Notably, 5 of 6 had predominant myoclonic seizures throughout the course of their epilepsy, associated with generalized spike-wave discharges, <100 milliseconds.

CONCLUSION

We observed myoclonic seizures to be a predominant seizure type in patients with trisomy 21, suggestive that trisomy 21 patients may have a unique pattern of Lennox-Gastaut syndrome.

The first post-natal clinical description of true mosaic complete tetrasomy 21: A case report

Tetrasomy 21 is a rare occurrence. Only 14 cases have been reported in the literature, 8 of which are partial tetrasomy cases and 6 which are complete tetrasomy cases. Of the incidences, no proband with true complete tetrasomy 21 has survived the neonatal period. We report complete mosaic tetrasomy 21 in a female infant with the typical Down syndrome phenotype, including Hirschsprung's disease and atrioventricular (AV) canal defect. This is in contrast to cases of partial tetrasomy 21, which often have an atypical trisomy 21 presentation and multiple nonspecific traits, including short stature, microcephaly, and developmental delays. This case demonstrates the difference in clinical presentation between the partial and complete subtype of tetrasomy 21 and provides the first postnatal clinical picture of an infant with true mosaic complete tetrasomy 21.

Epilepsy in Down Syndrome: A Highly Prevalent Comorbidity

Individuals with Down syndrome (DS) have an increased risk for epilepsy during the whole lifespan, but especially after age 40 years. The increase in the number of individuals with DS living into late middle age due to improved health care is resulting in an increase in epilepsy prevalence in this population. However, these epileptic seizures are probably underdiagnosed and inadequately treated. This late onset epilepsy is linked to the development of symptomatic Alzheimer's disease (AD), which is the main comorbidity in adults with DS with a cumulative incidence of more than 90% of adults by the seventh decade. More than 50% of patients with DS and AD dementia will most likely develop epilepsy, which in this context has a specific clinical presentation in the form of generalized myoclonic epilepsy. This epilepsy, named late onset myoclonic epilepsy (LOMEDS) affects the quality of life, might be associated with worse cognitive and functional outcomes in patients with AD dementia and has an impact on mortality. This review aims to summarize the current knowledge about the clinical and electrophysiological characteristics, diagnosis and treatment of epileptic seizures in the DS population, with a special emphasis on LOMEDS. Raised awareness and a better understanding of epilepsy in DS from families, caregivers and clinicians could enable earlier diagnoses and better treatments for individuals with DS.

Infantile Spasms and Trisomy 21: Unfavorable Outcomes with First-line Vigabatrin Therapy

Introduction:

Among children with infantile spasms (ISs), those with trisomy 21 (T21) and those with normal development at onset and no identifiable etiology (previously referred to as “idiopathic”) are expected to have relatively favorable outcomes. The study objective is to determine if differences exist in treatment response, relapse, and subsequent epilepsy between these two groups when vigabatrin is used as first-line treatment.

Methods:

In this retrospective study, patients were classified into the following groups and clinical features were compared: T21 (n = 24) and IS with normal development at onset and no identified etiology (n = 40; control group).

Results:

There was no significant difference in the age of IS onset, sex distribution, or treatment lag between the groups. The T21 compared to the control group required a higher mean number of anti-seizure therapies (3.6 vs. 1.9, p < 0.001), had more relapses [10 (42%) vs. 4 (10%), p < 0.005)], and had higher risk of subsequent epilepsy [11 (46%) vs. 8 (20%), p < 0.003]. Relapses were often delayed in the T21 group, with a mean of 8 months after IS cessation.

Conclusion:

Our results differ from most studies using steroids as first-line treatment where the groups were shown to have similar treatment response and T21 patients had a low risk of relapse and subsequent epilepsy. Therefore, our results suggest that vigabatrin as first-line treatment in T21 with IS may be less favorable than steroids.

Neurologic complications of Down syndrome: a systematic review

Down syndrome (DS) is one of the most well-recognized genetic disorders. Persons with DS are known to have a variety of co-morbid medical problems, affecting nearly all organ systems. Improved healthcare interventions and research have allowed for increased life span of persons with DS, although disorders of the neurologic system remain underexplored. The purpose of this systematic review is to provide clinically pertinent information on the neurological phenotypes of frequently occurring or clinically relevant conditions. A retrospective review of MEDLINE, Scopus, and Pubmed were used to identify sources among seventeen, clinically relevant, search categories. MeSH terms all contained the phrase "Down Syndrome" in conjunction with the topic of interest. 'Frequently-occurring' was defined as prevalent in more than 10% of persons with DS across their lifespan, whereas 'clinically-relevant' was defined as a disease condition where early diagnosis or intervention can augment the disease course. In total, 4896 sources were identified with 159 sources meeting criteria for inclusion. Seventeen clinical conditions were grouped under the following subjects: hypotonia, intellectual and learning disability, cervical instability, autism spectrum disorder, epilepsy, cerebrovascular disease, Alzheimer's disease and neuropsychiatric disease. The results of this review provide a blueprint for the clinical neurologist taking care of persons with DS across the age spectrum and indicate that there are many underrecognized and misdiagnosed co-occurring conditions in DS, highlighting the need for further research.

Epileptic spasms in individuals with Down syndrome: A review of the current literature

Epilepsy can occur in individuals with Down syndrome (DS), with epileptic spasms representing the most frequent seizure type in this population. Epileptic spasms can have devastating consequences on the development of individuals with the condition. This review sought to explore the lifetime prevalence and underlying mechanism of epileptic spasms in this population. We also aimed to review the response rate to various treatments, the relapse rate, and the development of subsequent epilepsy or autism in this population. A comprehensive literature search was conducted for articles discussing the lifetime prevalence, diagnosis, treatment, outcomes, or underlying etiology of epileptic spasms in animal models or individuals with DS. According to available literature, the global clinic-based lifetime prevalence of epilepsy in individuals with DS ranged from 1.6% to 23.1%, with epileptic spasms representing 6.7%-66.7% of these cases. Response rate to treatment with adrenocorticotropic hormone/corticosteroids was highest (81%) and has the most literature supporting its use, with other regimens, including vigabatrin and other antiepileptic drugs, having lower response rates. Epileptic spasms occur more frequently in children with DS than in the general population, though more studies are needed to determine the true lifetime prevalence of epileptic spasms in this population. Generally, children with DS and epileptic spasms tend to be more responsive to treatment and have better outcomes than children with epileptic spasms of unknown etiology (ie, without DS), in terms of response and relapse rates as well as the development of intractable epilepsy (eg, Lennox-Gastaut syndrome).

Modeling epileptic spasms during infancy: Are we heading for the treatment yet?

Infantile spasms (IS or epileptic spasms during infancy) were first described by Dr. William James West (aka West syndrome) in his own son in 1841. While rare by definition (occurring in 1 per 3200-3400 live births), IS represent a major social and treatment burden. The etiology of IS varies - there are many (>200) different known pathologies resulting in IS and still in about one third of cases there is no obvious reason. With the advancement of genetic analysis, role of certain genes (such as ARX or CDKL5 and others) in IS appears to be important. Current treatment strategies with incomplete efficacy and serious potential adverse effects include adrenocorticotropin (ACTH), corticosteroids (prednisone, prednisolone) and vigabatrin, more recently also a combination of hormones and vigabatrin. Second line treatments include pyridoxine (vitamin B6) and ketogenic diet. Additional treatment approaches use rapamycin, cannabidiol, valproic acid and other anti-seizure medications. Efficacy of these second line medications is variable but usually inferior to hormonal treatments and vigabatrin. Thus, new and effective models of this devastating condition are required for the search of additional treatment options as well as for better understanding the mechanisms of IS. Currently, eight models of IS are reviewed along with the ideas and mechanisms behind these models, drugs tested using the models and their efficacy and usefulness. Etiological variety of IS is somewhat reflected in the variety of the models. However, it seems that for finding precise personalized approaches, this variety is necessary as there is no "one-size-fits-all" approach possible for both IS in particular and epilepsy in general.

Multiorgan involvement and management in children with Down syndrome

AIM

To review multiorgan involvement and management in children with Down syndrome (DS).

METHODS

A literature review of articles from 1980 to 2019 using the MEDLINE interface of PubMed was performed using the following search terms- [Down syndrome] or [Trisomy 21] AND [Cardiology] or [Respiratory] or [neurodevelopment] or [epilepsy] or [musculoskeletal] or [immune system] or [haematological] or [endocrine] or [gastrointestinal] or [ophthalmological] or [Ear Nose Throat] or [dermatology] or [renal].

RESULTS

Congenital heart disease particularly septal defects occur in over 60% of infants with DS and 5%-34% of infants develop persistent pulmonary hypertension of the newborn irrespective of a diagnosis of congenital heart disease. Early recognition and management of aspiration, obstructive sleep apnoea and recurrent lower respiratory tract infections (LRTI) could reduce risk of developing pulmonary hypertension in later childhood. Children with DS have an increased risk of autistic spectrum disorder, attention deficit disorder and epilepsy particularly infantile spasms, which are associated with poor neurodevelopmental outcomes. Congenital anomalies of the gastrointestinal and renal system as well as autoimmune diseases, coeliac disease, arthropathy, thyroid dysfunction fold diabetes mellitus and dermatological conditions are more common. Hearing and visual anomalies are also well recognised association with DS (Table 1).

CONCLUSION

Children with DS are at an increased risk of multiorgan comorbidities. Organ-specific health surveillance may provide holistic care for the children and families with DS throughout childhood.

Outcomes of High-Dose Steroid Therapy for Infantile Spasms in Children With Trisomy 21

OBJECTIVE

We performed a retrospective chart review of patients with trisomy 21 and infantile spasms in our university-based pediatric epilepsy center between 2002 and 2016 in order to describe the clinical characteristics of children with these diagnoses as well as to evaluate their response to first-line treatments.

METHODS

Patients with infantile spasms were identified via the neurophysiology database. Charts were reviewed with attention to infantile spasms diagnosis, presence of trisomy 21, age of reported clinical onset, treatment lag, treatments used, response to treatment, imaging findings, electroencephalography (EEG) data, and developmental outcomes.

RESULTS

Of the 310 patients with infantile spasms, 24 also had trisomy 21. Three patients did not meet inclusion criteria. Ten of the 21 patients received nonstandard therapies first line; 2 of the 10 (20%) achieved spasm control, and 4 of the 8 who failed therapy (50%) progressed to Lennox-Gastaut syndrome. Eleven of the 21 patients received standard therapies as first-line treatments (10 with prednisolone according to the protocol in the United Kingdom Infantile Spasms Study [UKISS] and 1 with adrenocorticotrophic hormone [ACTH]). Nine of the 10 patients (90%) who received prednisolone achieved spasm resolution, 6 (60%) of these without relapse. The final patient (10%) failed prednisolone as well as ACTH. One patient received ACTH first line with success.

CONCLUSION

This is the only series to follow children with trisomy 21 and infantile spasms in which a significant proportion received UKISS-protocol prednisolone. It adds to current knowledge about safety, tolerability, and effectiveness of prednisolone in this group.

Infantile Spasms in Children With Down Syndrome: Identification and Treatment Response

Objectives. To evaluate infantile spasms in children with Down syndrome including assessment of efficacy of treatments, presence of treatment lag, and to identify risk factors that may predict the occurrence of infantile spasms in this population. Methods. Medical charts, electroencephalograms, and brain magnetic resonance images were evaluated in 37 children treated for infantile spasms at a single institution from 2005 to 2015. Results. Mean age at diagnosis was 9.16 months, with an average 1.38-month lag from spasms onset to start of medication. Prevalence of heart defects and pulmonary hypertension were significantly higher in those with infantile spams compared with those without. Eighty-one percent receiving adrenocorticotropic hormone as initial treatment experienced remission within 2 weeks, 94.1% had remission at 3 months compared with 18.8% at 2 weeks and 35.3% at 3 months for other first-line treatments. Type of treatment was the only predictor of good outcome. Conclusions. Results stress the importance of early recognition and adrenocorticotropic hormone treatment for this seizure disorder in children with Down syndrome.

Neuroprotective and Antiamnesic Effects of Mitragyna inermis Willd (Rubiaceae) on Scopolamine-Induced Memory Impairment in Mice

Aim. To assess memory improvement and neuroprotective and antioxidant effects of Mitragyna inermis (M. inermis) leaf decoction on the central nervous system. Methodology. Leaf decoction of M. inermis was tested on learning and memory in normal and scopolamine-induced cognitive impairment in mice using memory behavioral tests such as the Morris water maze, object recognition task, and elevated plus maze. Oxidative stress enzymes-catalase, superoxide dismutase, and the thiobarbituric acid reactive substance, a product of lipid peroxidation-were quantified. In each test, mice 18 to 25 g were divided into groups of 5. Results. The extract reversed the effects of scopolamine in mice. The extract significantly increased discrimination index in the object recognition task test and inflexion ratio in the elevated plus maze test. The times spent in target quadrant in MWM increased while the transfer latency decreased in mice treated by M. inermis at the dose of 196.5 mg/kg. The activity levels of superoxide dismutase and catalase were significantly increased, whereas the thiobarbituric acid reactive substance was significantly decreased after 8 consecutive days of treatment with M. inermis at the dose of 393 mg/kg. Conclusion. These results suggest that M. inermis leaf extract possess potential antiamnesic effects.