Understanding Down syndrome

Introduction

Down syndrome, also known as trisomy 21, is a genetic disorder that affects physical and intellectual development. It is one of the most common chromosomal conditions observed in humans. This document aims to provide a detailed exploration of Down syndrome, including its causes, symptoms, diagnosis, treatment options, and the various aspects of living with the condition in an Indian context.

What is Down Syndrome?

Down syndrome is a genetic disorder caused by the presence of an extra copy of chromosome 21. Normally, humans have 46 chromosomes in each cell, arranged in 23 pairs. Individuals with Down syndrome have three copies (trisomy) of chromosome 21, leading to a total of 47 chromosomes. This additional genetic material alters the course of development and causes the characteristic features associated with the syndrome.

Types of Down Syndrome

There are three main types of Down syndrome:

1. Trisomy 21: The most common type, accounting for about 95% of cases. Every cell in the body has three copies of chromosome 21 instead of two.
2. Translocation Down Syndrome: In about 3-4% of cases, an extra part or a whole chromosome 21 is attached (translocated) to a different chromosome. The total number of chromosomes remains 46, but extra genetic material from chromosome 21 is present.
3. Mosaic Down Syndrome: This rare form (1-2% of cases) occurs when some cells have three copies of chromosome 21, while others have the typical two copies. The severity of symptoms may vary depending on the proportion of affected cells.

Causes and Risk Factors

Down syndrome is not caused by anything a parent does or does not do during pregnancy. It is a random genetic occurrence, but certain risk factors increase the likelihood:

• Maternal Age: The risk increases with the mother’s age, especially after 35 years. However, since younger women have more children overall, most babies with Down syndrome are born to mothers under 35.
• Previous Child with Down Syndrome: Parents who have had one child with Down syndrome have a slightly increased risk of having another.
• Carrier Parents: In rare cases, one parent may be a carrier of a translocated chromosome 21, which can be identified through genetic counselling.

Physical and Intellectual Characteristics

Individuals with Down syndrome share certain physical traits, though not all features are present in every individual. Common characteristics include:

• Flat facial profile
• Upward slanting eyes with epicanthic folds
• Small ears and mouth
• Short neck
• Single deep crease across the palm (simian crease)
• Poor muscle tone (hypotonia)
• Short stature

Intellectual development is affected, leading to mild to moderate intellectual disability. Children with Down syndrome usually reach developmental milestones later than their peers, such as walking and talking.

Medical Complications Associated with Down Syndrome

People with Down syndrome are at higher risk for several health conditions, including:

• Congenital heart defects (present in up to 50% of cases)
• Hearing and vision problems
• Thyroid disorders (especially hypothyroidism)
• Respiratory and ear infections
• Leukaemia (increased risk compared to the general population)
• Sleep apnoea
• Gastrointestinal problems, such as duodenal atresia or Hirschsprung’s disease
• Higher incidence of Alzheimer’s disease at an earlier age

With advances in medical care, most of these conditions can be managed effectively, and life expectancy for people with Down syndrome has increased significantly, often reaching 60 years or more.

Diagnosis

Down syndrome can be diagnosed during pregnancy (prenatally) or after birth (postnatally).

Prenatal Diagnosis

• Screening Tests: Blood tests and ultrasound scans can estimate the likelihood of Down syndrome. Common screening tests include the nuchal translucency scan (between 11–14 weeks), the double marker test, and the quadruple marker test.
• Diagnostic Tests: If screening tests indicate a higher risk, diagnostic tests such as amniocentesis, chorionic villus sampling (CVS), or cell-free fetal DNA testing can confirm the diagnosis by analysing the baby’s chromosomes.

Postnatal Diagnosis

After birth, Down syndrome is suspected based on physical features and confirmed by a chromosomal analysis called karyotyping.

Management and Treatment

There is no cure for Down syndrome, but early intervention and supportive therapies can help individuals reach their full potential. Management typically includes:

• Early Intervention: Programmes that provide physiotherapy, occupational therapy, and speech therapy from infancy can significantly improve developmental outcomes.
• Medical Care: Regular check-ups and screenings for associated health problems are essential. Heart defects, hearing and vision issues, and thyroid function should be monitored and treated as needed.
• Inclusive Education: Children with Down syndrome benefit from inclusive education, where they learn alongside their peers in mainstream schools with necessary support.
• Social and Emotional Support: Family, community, and peer support play a crucial role in the well-being of individuals with Down syndrome. Participation in social activities and vocational training can enhance quality of life.

In India, several organisations and support groups such as the Down Syndrome Federation of India and the National Trust offer resources, counselling, and advocacy for families.

Living with Down Syndrome: Social and Cultural Perspectives

In Indian society, awareness about Down syndrome is increasing, but stigma and misconceptions still exist in some communities. Families may face challenges in accessing inclusive education, healthcare, and social acceptance. Advocacy and awareness campaigns are gradually changing perceptions, promoting dignity, and encouraging acceptance of individuals with Down syndrome.

Many people with Down syndrome lead fulfilling lives, participate in sports, arts, and community activities, and even pursue employment. Parental support, access to healthcare, and inclusive policies are key factors in enhancing their quality of life.

Genetic Counselling and Prevention

Genetic counselling is recommended for families with a history of Down syndrome or those identified as carriers of translocated chromosome 21. Counsellors can explain the risks, testing options, and reproductive choices to help families make informed decisions.

While there is no way to prevent Down syndrome completely, prenatal screening and diagnostic techniques allow parents to be better prepared for the birth of a child with the condition.

Nursing Care of Patients with Down Syndrome

Nursing care for individuals with Down syndrome is comprehensive and tailored to address their unique physical, developmental, and psychosocial needs. Effective nursing interventions focus on promoting optimal health, supporting development, preventing complications, and facilitating social inclusion.

1.Assessment and Monitoring

Nurses play a pivotal role in the early identification and ongoing assessment of health issues. Routine monitoring includes tracking growth and development milestones, screening for congenital heart defects, thyroid dysfunction, hearing and vision impairments, and signs of respiratory or gastrointestinal problems. Observing for signs of infection, especially due to a potentially compromised immune system, is also essential.

2.Health Promotion and Preventive Care

Health promotion involves educating families about the importance of regular medical check-ups, immunisations, and dental care. Nurses guide families on nutrition, physical activity, and sleep hygiene to support overall well-being. Preventive care also includes monitoring for obesity and encouraging participation in physical activities suitable for the individual’s abilities.

3.Developmental Support

Supporting the developmental needs of patients with Down syndrome is a key nursing responsibility. Nurses collaborate with multidisciplinary teams—such as physiotherapists, speech and language therapists, and occupational therapists—to create and implement individualised care plans. Early intervention programmes and stimulation activities are encouraged to maximise developmental potential.

4.Family Education and Support

Nurses provide families with information about Down syndrome, available resources, and coping strategies. They offer emotional support, address parental concerns, and assist with navigating educational and community services. Encouraging family involvement in care decisions fosters empowerment and promotes positive outcomes.

5.Facilitating Inclusive Environments

Nursing care extends beyond direct health management to advocating for inclusive education and social participation. Nurses may liaise with schools and community groups to ensure that the individual’s needs are met and to promote acceptance and understanding among peers. They also support vocational training and transition planning for adulthood.

6.Managing Associated Health Conditions

Addressing co-morbidities such as heart defects, respiratory infections, hearing and vision issues, and thyroid disorders is an integral part of nursing care. Nurses ensure adherence to prescribed treatments, facilitate specialist referrals, and educate families about symptom recognition and management.

7.Promoting Independence and Dignity

Nurses encourage self-care skills according to the patient’s developmental level, fostering independence and self-esteem. Respecting the individual’s preferences and promoting autonomy in daily living activities are central to person-centred care.

8.Psychosocial Support

Supporting the emotional well-being of individuals with Down syndrome and their families is vital. Nurses help address behavioural challenges, provide guidance on social skills, and connect families to support groups and counselling services as needed.

9.Ethical and Cultural Considerations

Nurses must be sensitive to cultural beliefs and practices, especially in societies where stigma or misconceptions about Down syndrome may persist. They act as advocates for the rights of individuals with Down syndrome, promoting dignity, acceptance, and equal opportunities within healthcare and the wider community.

REFERENCES

1. Centers for Disease Control and Prevention. Facts about Down Syndrome. https://www.cdc.gov/ncbddd/birthdefects/downsyndrome.html.
2. Cuckle HS. Primary Prevention of Down’s Syndrome. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1168873/. Int J Med Sci. 2005; 2(3):93–99.
3. Bull MJ. Down syndrome. New England Journal of Medicine. 2020; doi:10.1056/NEJMra1706537.
4. March of Dimes. Down-Syndrome. https://www.marchofdimes.org/complications/down-syndrome.aspx.
5. National Down Syndrome Society. About Down Syndrome. https://ndss.org/about.
6. Antonarakis SE, et al. Down syndrome. Nature Reviews: Disease Primer. 2020; doi:10.1038/s41572-019-0143-7.
7. Tsou AY, et al. Medical care of adults with Down syndrome: A clinical guideline. JAMA. 2020; doi:10.1001/jama.2020.17024.
8. National Library of Medicine. Downsyndrom. https://medlineplus.gov/genetics/condition/down-syndrome/#inheritance.
9. U.S. Department of Health and Human Services. Down Syndrome. https://www.nichd.nih.gov/health/topics/down/conditioninfo.
10. Kazemi M, Salehi M, Kheirollahi M. Down Syndrome: Current Status, Challenges and Future Perspectives. Int J Mol Cell Med. 2016 Summer;5(3):125-133. Epub 2016 Aug 10. PMID: 27942498; PMCID: PMC5125364.

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