Medical management of children with Down syndrome

Down syndrome, trisomy 21, is the most common autosomal trisomy, and commonest identifiable cause of learning disability. Despite current prenatal screening practice birth prevalence continues to be around 1/1000 live births.Children with Down syndrome have an increased risk of congenital abnormalities and a wide range of treatable medical problems. Paediatricians have a key role in ensuring that these are recognized and treated so that the children's progress is not hampered by additional secondary but preventable disability, and health problems do not prevent them reaching their potential.In this article we consider the Paediatrician's role with a suggested approach to medical management throughout childhood, and a review of the most frequently occurring health issues. These include cardiac, respiratory, gastrointestinal and haematological disorders, thyroid dysfunction, hearing and vision problems, cervical spine and other orthopaedic problems, immune and autistic spectrum disorders, growth and sexual development.     

Medical management of children with Down syndrome

Down syndrome, trisomy 21, is the most common autosomal trisomy, and commonest identifiable cause of learning disability. Despite current prenatal screening practice birth prevalence continues to be around 1/1000 live births.Children with Down syndrome have an increased risk of congenital abnormalities and a wide range of treatable medical problems. Paediatricians have a key role in ensuring that these are recognized and treated so that the children’s progress is not hampered by additional secondary but preventable disability, and so that health problems do not prevent them reaching their potential.In this article we consider the paediatrician’s role with a suggested approach to medical management throughout childhood, and a review of the most frequently occurring health issues. These are cardiac, respiratory, gastrointestinal and haematological disorders, thyroid dysfunction, hearing and vision problems, cervical spine and other orthopaedic problems, immune and autistic spectrum disorders, growth and sexual development.     

Down syndrome: imaging of multiorgan involvement.

Down syndrome (trisomy 21) has many manifestations that affect multiple organ systems, and we describe the wide array of imaging findings. Common cardiovascular and gastrointestinal entities are congenital heart disease (atrioventricular canal), bowel atresias (duodenal and anal), and Hirschsprungs disease. Children with Down syndrome have an 18-20 fold increased incidence of leukemia. Pulmonary hypoplasia, lung cysts, and pig bronchus (origin of the right upper lobe bronchus from the trachea) have been described. Neurologic findings include mineralizing vasculopathy of the basal ganglia, Moyamoya disease, and cerebellar/vermian hypoplasia. Musculoskeletal manifestations are numerous and include eleven ribs, hypersegmented sternum, abnormal pelvis, joint laxity/dislocations, and DDH (developmental dysplasia of the hip). Of special importance is the "triple jeopardy" of the upper cervical spine (atlanoaxial subluxation, hypoplastic posterior arch of C1, and atlantooccipital instability) and the resulting controversial cervical spine radiographic screening of children with Down syndrome. Knowledge of the many anomalies associated with Down syndrome can aid the clinician, not only in diagnosing abnormalities in these patients, but also in counseling families for potential problems that can occur in these children.     

Down syndrome and craniovertebral instability. Topic review and treatment recommendations

The diagnosis and management of occipital-atlantal and atlantoaxial instability in Down syndrome patients is a challenging problem in pediatric spine surgery. To date, no systematic review of this topic has been presented on this confusing and sometimes contentious issue. This topic review will focus on the biomechanical and radiographic foundations for which treatment recommendations in Down syndrome patients are made. In addition, otolaryngologic and anesthetic considerations in Down syndrome are also discussed, as well as advances in surgery that have made the operative fusion of these patients easier and safer. Copyright Copyright 1999 S. Karger AG, Basel     

Atlanto-occipital subluxation in Down syndrome

Atlanto-occipital subluxation (AOS) in individuals with Down syndrome is discussed using five new cases and nine patients previously presented in the literature. Although AOS is likely due to ligamentous laxity, it was associated with atlantoaxial instability in only two youngsters. Reducible C1–C2 rotary subluxation was present in a third. Posterior movement of the occiput with respect to C1 occurred on extension and reduced on flexion in all but one individual who demonstrated anterior subluxation. Neurological problems are described in only two individuals: one with severe atlantoaxial subluxation (AAS) and the other with multiple cervical spine anomalies. Since AOS is usually detected on films obtained to screen children with Down syndrome for AAS, the atlanto-occipital joint should be carefully studied on these radiographs. The clinical significance of AOS needs to be determined.     

Keeping children and young people with Down syndrome healthy

Down syndrome (trisomy 21) is a common identifiable cause of intellectual disability. People with Down syndrome are individuals, and while there are many shared characteristics, there is considerable variability in how the syndrome manifests. Understanding the condition and its impact on individual lives can help maintain and promote health, and enable individuals to achieve their potential. There are some conditions that are more frequently seen in individuals with Down syndrome, and as such it is important not to fall into the trap of labelling all symptoms as ‘part of Down syndrome’. Awareness of some of the more frequently seen conditions will help in understanding and aid timely investigation and management - enabling individuals to access the support and care they need. In this article, we focus on our role as health professionals in supporting families, children and young people with Down syndrome. We describe some of the conditions seen more commonly in individuals with Down syndrome and our role in screening, identification and management of these.     

Down syndrome. Cervical spine abnormalities and problems

A review of the radiographs of 34 individuals with Down syndrome (DS), between 5 and 21 years of age, demonstrated subluxation of atlantoaxial instability (C1-C2) greater than 5 mm in three of the 34 individuals (9 percent). This is in general agreement with previously reported ranges of 10 to 20 percent. A review of the cervical spine radiographs of adults with DS, between 26 and 42 years of age, showed no subluxation but significant degenerative changes of the cervical spine with spur formation, narrowing of foramina, narrowing of the disc inner space, and osteophyte formation. In both the DS child and the DS adult, the cervical spine may be an area of significant potential problems. In all cases any complaints of cervical pain or historical/clinical findings suggestive of neurologic involvement should initiate evaluation of the cervical spine. Baseline radiographic studies of the cervical spine are indicated in all DS children older than 5 years of age and should be considered in all DS adults, particularly those 30 years of age and older.     

Atlanto-axial instability in children with Down syndrome

One hundred fifty-eight patients with Down syndrome underwent roentgenologic examinations of the cervical spine in neutral position, in hyperflexion, and in hyperextension. Fifteen children with Down syndrome were found to have a distance between the joint surfaces of 5 mm and more. The majority of these children were asymptomatic, one child displayed hyperactive deep tendon reflexes and two children were symptomatic and underwent surgery.     

Spastic quadriplegia in Down syndrome with congenital duodenal stenosis/atresia

Down syndrome is an autosomal chromosome disorder, characterized by intellectual disability and muscle hypotonia. Muscle hypotonia is observed from neonates to adulthood in Down syndrome patients, but muscle hypertonicity is extremely unusual in this syndrome. During a study period of nine years, we found three patients with severe spastic quadriplegia among 20 cases with Down syndrome and congenital duodenal stenosis/atresia (3/20). However, we could find no patient with spastic quadriplegia among 644 cases with Down syndrome without congenital duodenal stenosis/atresia during the same period (0/644, P < 0.05). Further, we did not find any cases with spastic quadriplegia among 17 patients with congenital duodenal stenosis/atresia without Down syndrome admitted during the same period to use as a control group (0/17, P < 0.05). Our results suggest that congenital duodenal stenosis/atresia is a potential risk factor for spastic quadriplegia in patients with Down syndrome. Long‐term survival is improving, and the large majority of people with Down syndrome are expected to live well into adult life. Management and further study for the various problems, representing a low prevalence but serious and specific to patients with Down syndrome, are required to improve their quality of life.     

Atlantoaxial instability in individuals with Down syndrome: a fresh look at the evidence

In 1984, the Committee on Sports Medicine of the American Academy of Pediatrics published in this journal a statement on the remarkably high incidence of atlantoaxial instability among individuals with Down syndrome. On the assumption that this instability, demonstrable through a specified series of lateral x-ray films of the neck, constituted a predisposition to cervical spine dislocation with subsequent spinal cord compression, the Academy supported and made more specific a series of recommendations that had originated from the Kennedy Foundation a year previously. In essence, for those persons who are found to have the radiographic sign of instability, participation in sports should be restricted. Because the implementation of these recommendations could deprive tens of thousands of individuals with Down syndrome of activities that are emotionally and physically beneficial and because of the rarity of reported cervical dislocations associated with injury, a case review was done. Included were those cases cited as support for the recommendations along with additional reports that had been omitted and a few cases reported subsequently. Little support for the hypothesis that atlantoaxial "instability" is a predisposing factor to "dislocation" was found, although much was found to indicate an urgent need for carefully designed longitudinal studies. Because nearly all of the cases of actual dislocation were preceded by at least several weeks of readily detectable physical signs, a physical examination with careful attention to neurologic signs prior to participation in sports is more predictive of potential or impending dislocation than the radiologic criteria currently recommended.     

Diagnosis and Management of Down Syndrome

Down syndrome is the commonest chromosomal disorder causing mild to moderate intellectual disability, yet it is one of the neglected disorder amongst practicing physicians. Children with Down syndrome when intervened early by speech therapy, physiotherapy and occupational therapy and given proper medical attention for different health issues, can have a better long term outcome as compared to other genetic causes of intellectual disability. This paper would help the general practitioners to identify children with Down syndrome and to manage the common problems associated with this condition.     

The Special Olympics athlete: evaluation and clearance for participation

Evaluating and clearing the Special Olympics athlete for participation in sports and recreational activities can be a challenging task for a primary care physician. Radiographic clearance of the cervical spine is mandatory for all athletes with Down syndrome. Regular physical activity for this special population has measurable physiologic and psychosocial benefits.     

Atlantoaxial instability in Down syndrome: roentgenographic, neurologic, and somatosensory evoked potential studies

To identify patients with Down syndrome and asymptomatic atlantoaxial instability who are at increased risk for developing neurologic symptoms, we studied 27 patients with this skeletal disorder and compared them with an age- and sex-matched group of 27 patients with Down syndrome without atlantoaxial instability. A third group of six patients had symptomatic atlantoaxial instability. The mean atlanto-dens intervals and the mean spinal canal widths among the three groups were significantly different. There were no significant differences in mean composite neurologic scores and somatosensory evoked responses between patients in the asymptomatic group and those in the control group. However, when a subsample of patients with high and low latencies (greater than 1 SD below and above the mean) was formed and comparisons were made with roentgenographic findings, there was a high correspondence between somatosensory evoked potential latencies and atlanto-dens interval measurements. We conclude that no single assessment technique, but a combined approach using roentgenographic, CT scan, neurologic, and neurophysiologic investigations, will provide information of the risk status of patients with Down syndrome and atlantoaxial instability.     

Risk of death for children with down syndrome and sepsis

OBJECTIVE: To determine differences in case fatality rates between children with and without Down syndrome. STUDY DESIGN: We used the Pediatric Health Information System (PHIS) database, which includes demographic and diagnostic data from freestanding children's hospitals. Using Poisson regression, we determined the risk of mortality from sepsis for children with Down syndrome, after controlling for potential confounding factors. RESULTS: A total of 35,645 patients met our inclusion criteria, of which 3936 (11%) died during hospitalization. Altogether, 620 of the included patients also had a diagnosis of Down syndrome; 106 (17%) of these died during hospitalization. Children with Down syndrome had significantly elevated risk of mortality (mortality rate ratio = 1.30; 95% confidence interval = 1.06 to 1.59) after adjusting for potential confounding factors including demographics, pathogens, and concomitant conditions. CONCLUSIONS: Children with Down syndrome and sepsis have elevated risk of mortality. These findings have implications for treatment decisions, communications about prognosis, and future research.     

Relative rather than absolute macroglossia in patients with Down syndrome: implications for treatment of obstructive sleep apnea

BACKGROUND: Children with Down syndrome are described as having macroglossia as well as midface hypoplasia. We reviewed anatomic parameters on MRI to determine whether adolescents with Down syndrome have true macroglossia or relatively large tongues compared to the small size of their oral cavity. This has implications for the treatment of obstructive sleep apnea, which occurs at a relatively high rate among patients with Down syndrome. OBJECTIVE: To determine whether adolescents with Down syndrome have relative rather than true macroglossia. MATERIALS AND METHODS: On sagittal and axial MR images, parameters for tongue size (area in sagittal midline), the bony craniofacial confines of the retroglossal pharynx (distance between the mandibular rami and distance between the posterior aspect of the mental mandible and the anterior aspect of the spine), and the size of the tongue relative to the craniofacial bony parameters [tongue area/(transverse diameter x anterior-to-posterior diameter)] were compared between 16 patients with Down syndrome and 16 age- and gender-matched controls. RESULTS: The tongue area was significantly smaller in patients with Down syndrome (2,432 mm(2)) than in the control patients (2,767 mm(2); P=0.02). The craniofacial bony parameters were also smaller in patients with Down syndrome than in the controls (left-right 69.8 vs. 80.1 mm, P<0.001; anterior-posterior 64.2 vs. 74.9 mm, P<0.001). However, the size of the tongue relative to the craniofacial parameters was larger in the patients with Down syndrome (0.54) than in the controls (0.46; P<0.001). CONCLUSION: Children with Down syndrome do not have true macroglossia but have relatively large tongues compared to the bony confines of the oral cavity.     

A young child with trisomy 21. Medical aspects: myths and reality

Everyone is familiar with Down syndrome but both the general public and the medical profession are inadequately educated about this disability. In this paper, medical aspects are briefly discussed. The incidence of Down syndrome, which is one in 700, is stable. Maternal age is under 35 years in 75% of cases. Fetal ultrasonography and biochemical screening can be expected to increase the frequency of antenatal fetal chromosome analysis. One of every three children with Down syndrome has congenital heart disease (common atrioventricular canal in 50% of cases); pulmonary hypertension develops unusually early and, consequently, prompt surgical treatment may be indicated. Hyperlaxity is variable and has little effect on motor development. Ocular anomalies and hearing loss should be detected and treated early since they have the potential for increasing the child's intellectual impairment. The life span of Down syndrome patients is increasing gradually as a result of medical advances and changes in lifestyles. Every Down syndrome child has abilities, a social and familial environment, and a personality, and all these elements are closely interrelated. Each child is a unique person to be discovered.     

Haematology of Down syndrome

Down syndrome is a common congenital disorder affecting approximately 1/1000 live births. Newborns and children with Down syndrome may present with many haematological problems. In addition, benign abnormalities of the blood count and blood film, which may manifest at any age, population-based and cancer-based registries and clinical trials suggest there is a approximately 12-fold increased risk of acute lymphoblastic leukaemia in the age group of 5-30 years that rises to approximately 40-fold in children younger than 5 years, and that there is a approximately 150-fold increased risk of acute myeloid leukaemia in children younger than 5 years. There is also a virtually unique predisposition to a transient neonatal leukaemia, known as transient abnormal myelopoiesis. Deaths from leukaemia, in part, account for the excess mortality associated with Down syndrome. This article reviews the clinical presentation and the progress made in the management of these disorders over the past decade. It also briefly considers the recent exciting scientific advances that have potential to transform management of leukaemia in children with Down syndrome and also have implications for management of childhood leukaemia more generally.     

A study protocol of a randomised controlled trial to investigate if a community based strength training programme improves work task performance in young adults with Down syndrome

Background  

Muscle strength is important for young people with Down syndrome as they make the transition to adulthood, because their workplace activities typically emphasise physical rather than cognitive skills. Muscle strength is reduced up to 50% in people with Down syndrome compared to their peers without disability. Progressive resistance training improves muscle strength and endurance in people with Down syndrome. However, there is no evidence on whether it has an effect on work task performance or physical activity levels. The aim of this study is to investigate if a student-led community-based progressive resistance training programme can improve these outcomes in adolescents and young adults with Down syndrome.     

Cervical myelocystoceles and meningoceles: long-term follow-up

Little is known about the long-term prognosis of patients with cervical myelocystoceles and meningoceles. In this study, we report the long-term follow-up (average 10 years and 8 months) of 8 patients with cervical myelocystoceles and meningoceles. Neurologic, orthopedic, urologic and psychosocial status was assessed on long-term follow-up. The results indicate that in patients with cervical myelocystoceles, neurologic deficits become noticeable in the first year of life as the infant matures. Motor deficit was common in these patients, whereas sensory and urologic deficits did not occur. We believe that this is related to underlying myelodysplasia. In addition, patients with cervical myelocystoceles tend to have significant orthopedic problems. In contrast, patients with cervical meningoceles do not have neurologic deficits, but do develop mild orthopedic problems.     

An overview and update regarding medical problems in down syndrome

Down syndrome is the commonest occuring syndrome, and because of the high risk of congenital heart disease, these children are frequently seen at cardiology clinics and wards. However, these individuals are also likely to have a variety of other-problems, both congenital and acquired, which may impinge on the medical and surgical management of cardiac problems. It is therefore important for the paediatric cardiology community to maintain a minimum level of expertise in other noncardiac aspects of the syndrome. This paper reviews Down syndrome, lists congenital and acquire disorders that may occur, and briefly addresses recent advances in the understanding of this condition.