Discussion response

Down syndrome, also known as Trisomy 21, is a genetic disorder characterized by an extra, or third copy of chromosome 21. Down syndrome is known as the most common occurring chromosomal abnormality in humans (Aktar, 2021). According to McCance & Huether, Down syndrome is seen in 1 in 800 live births (2019).  The following paragraphs will discuss the etiology, clinical presentation, and risk factors associated with Down syndrome, along with discussion of treatment and/or management. 

            Genetically speaking, Down syndrome results from an aneuploid cell that contains three copies of one chromosome, specifically chromosome 21. Trisomy 21 results from genetic nondisjunction, which is defined as the failure of chromosomes or sister chromatids to separate, resulting in production of daughter cells with abnormal numbers of chromosomes (McCance & Huether, 2019). Newborns with trisomy of chromosome 21 can survive, but three-fourths of affected fetuses spontaneously abort before or at birth (McCance & Huether, 2019). Down syndrome is the most common genetic condition associated with intellectual disability. It has a specific clinical presentation, distinguishing itself from other chromosomal conditions (Bull, 2020).

            Individuals with Down syndrome have distinctive facial characteristics, including a low nasal bridge, epicanthal folds, protruding tongue, and flat, low-set ears (McCance & Huether, 2019). They tend to be short in stature accompanied with decreased muscle tone. Along with distinct physical characteristics, those affected with Down syndrome are at increased risk of developing neurological deficits, congenital heart defects, and gastrointestinal abnormalities (Aktar, 2021). In addition, individuals with Down syndrome have a decreased ability to fight respiratory infections, and an increased risk of developing leukemia. By the age of 40, most develop symptoms that mirror Alzheimer disease, due to the fact that chromosome 21 carries a contributing gene that leads to Alzheimer development. Life expectancy averages around 60 years of age (McCance & Huether, 2019).  

            While there are little known risk factors for bearing a child with Down syndrome, it is known that increased maternal age is the most common risk factor. Although women of all ages can birth a child with Down syndrome, there is an increased number of cases in women over the age of 35 (Diamandopoulos & Green, 2018). Prenatal screening in the first and second trimester, including an ultrasound and blood screen can help determine presence of Down syndrome in the unborn fetus. These tests are normally performed between 9 and 12 weeks of gestation (Diamandopoulos & Green, 2018).

            In a newborn child, Down syndrome should be differentiated from other congenital conditions with the presentation of hypotonia, poor feeding and growth, and distinctive facial features. Three common differential diagnoses include isolated hypotonia, congenital hypothyroidism, and Zellweger syndrome (Akhtar, 2021). These diseases can be differentiated from Down Syndrome by comparing the clinical features of each. A child with isolated hypotonia simply presents with decreased muscle tone but does not have the distinctive facial characteristics of an individual with Down syndrome. A child with congenital hypothyroidism presents with hypotonia, poor feeding and poor growth, but does not present with a single palmar crease, epicanthal folds, or a flattened head and face. Zellweger syndrome is more difficult to distinguish, as they share similar body and facial features, including hypotonia, poor feeding, poor growth, single palmar crease, epicanthal folds, and flattened face and head. A key difference here absence of abundant neck skin, protruding tongue, and almond eyes that distinguish Down syndrome (Khadpe et al., 2019).  Early diagnosis, appropriate metabolic workup, and phenotype comparison are important in distinguishing Down Syndrome from Zellweger syndrome (Khapde et al., 2019).

            Treatment of Down syndrome is primarily symptomatic, due to the fact that complete recovery is not yet possible (Akhtar, 2021). Management of individuals with Down syndrome may include several specialist referrals, such as a clinical geneticist for genetic testing and counseling, an ophthalmologist, orthopedic surgeon, cardiologist, dermatologist, gastroenterologist, physical therapist, ENT surgeon, and a behavioral specialist. Specific referrals rely heavily on severity of symptoms (Akhtar, 2021). Family education is important in managing an individual with Down syndrome, as parents need to have an increased awareness of associated medical conditions, including their signs and symptoms (Akhtar, 2021). Despite the odds, many individuals with Down syndrome live a fulfilled and productive life with lifespan continuing to increase over time. Can you recall a positive patient care experience or situation with an individual with Down syndrome?  

References

Akhtar, F. (2021, December 12). Down syndrome. U.S. National Library of Medicine. Retrieved January 26, 2022, from https://www.ncbi.nlm.nih.gov/books/NBK526016/

 Bull, M. J. (2020). Down syndrome. New England Journal of Medicine, 382(24), 2344-2352.

Diamandopoulos, K., & Green, J. (2018). Down syndrome: An integrative review. Journal of Neonatal Nursing, 24(5), 235241. https://doi.org/10.1016/j.jnn.2018.01.001

Khadpe, T., Kondekar, A., Anand, V., & Ghildiyal, R. (2019, February 14). Zellweger syndrome: A downs syndrome mimic. Pediatric Review: International Journal of Pediatric Research. Retrieved January 26, 2022, from https://pediatrics.medresearch.in/index.php/ijpr/article/view/469

McCance, K. L., & Huether, S. E. (2019). Pathophysiology: The biologic basis for disease in adults and children. Elsevier.