Edward’s Syndrome: What if He Survives?

By: Muhamad Na’im B. Ab Razak

4^th Year Medical Student, Universiti Sains Malaysia

Five and half years old Malay boy with known cases of Edward Syndrome with global developmental delay is the last out of three siblings from non-consangious marriage presented to Paediatric Clinic for regular follow up. He comes from a family with low socio-economic status. His eldest brother was diagnosed with vesicourethral reflux with renal scarring and his maternal uncle has Down’s syndrome. Both of the parents were 33 years old at the time of his birth and he was delivered via emergency LSCS at full term due to respiratory distress. He was subsequently admitted to NICU for 11 days due to respiratory distress, however did not require any ventilation. At the time of birth, he was noted to have frontal bossing with hypoplastic maxilla, microcephaly, low set ears, prominent beaked nose, broad great toes and broad thumbs with abnormal hand simian creases (zigzag line). His chromosomal study shows karyotype 46, XY, t(18:18). There is Isochromosome of 18q with accompanying deletion of the p arm of chromosome 18. Previously, patient was recurrently admitted for left inguinal hernia, laryngomalacia and bronchopneumonia. Patient also has cortical blindness but no skeletal and cardiac abnormality. His mother insists on active resuscitation if anything goes wrong with him. Currently, patient still unable to sit but can roll over, can respond to call and sound by turning heads and able to babbling.

Discussion

Trisomy 18 was described by Edwards et al and Smith et al in the year of 1960 and it is the second most common autosomal trisomy in live born children after Down's syndrome. It is most commonly a result from total trisomy with small fraction of it is due to Mosaicism and Translocation.

The syndrome impacts severely upon intellectual and physical development and is three to four times more common in female with total incidence is about 1 in 5000 to 1 in 7000 live births.

According to Harold Chen, it is being estimated that 95% of conceptuses with trisomy 18 die as embryo or fetus and 5-10% of affected children survive beyond first year of life. The life born infants with trisomy has estimated probability of survival to age one month with 38.6% and 8.4% to age one year and median survival time was 14.5 days. The longest long term survival that has been reported till today is up to age 27 years old. High mortality rate is usually due to the presence of cardiac and renal malformations, feeding difficulties, sepsis, and apnea caused by CNS defects. Severe psychomotor and growth retardation are invariably present in those who survive beyond infancy

Zilfalil et al wrote that the pathognomic segment responsible for Edward's phenotype is thought to be located in the q arm. Hence Isochromosome 18q (complete triplication of q arm) is diagnosed as Edwards Syndrome. Triplication of various segment of the q arm does not produce the same phenotype. Individuals with partial trisomy 18 such as 18q2 trisomy, 18p and q1 trisomy have been reported in literature with range of severity from relatively mild phenotype with no internal organ malformation to classic characteristic of Edward's Syndrome.

Even though the risk factor for trisomy 18 is known to increase with high maternal and paternal age, the risk association of Isochromosome 18q with maternal and paternal ages has not been studied.

For those who have survived, there is no cure for Edward’s syndrome. Treatment usually more oriented to presenting symptoms and surgical correction of organ abnormality.

Patient with Edward’s usually died mostly due to congenital cardiac complication. Cardiac surgery has shown to be effective in prolonging the life of the patient.

However, in this case, patient has no cardiac abnormality which suggests that he might have a longer life. However, risk of death still high especially in term of sepsis. Therefore, the right for resuscitation should be discussed properly with the parents.

In view of low economic status, the patient’s condition might be impaired in term of inadequate nutritional support, emotional support and tiredness of parent to strictly monitor the patient. Therefore, this factor might lessen the patient’s life. In this case, parents still insist on active resuscitation, presumably due to tight bonding between the mother and son. However, some of the parents might already give up and ready to let the patient go. Even so, they might need a day or two before fully mentally prepared to accept the loss of the child. Thus, temporary ventilation might help the parents. Therefore, agreement should be made between physician and the parents in regards the best option for the patient’ sake.

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Reference

1) Harold Chen, "Trisomy 18", eMedicine, 2009

http://emedicine.medscape.com/article/943463-overview

2) Marilyn J. field & Richard E. Behrman, “ When Children Die: Improving palliative and End of Life Care for children and Their Families”, The National Academic Press, Washington, 2003

3) Pal S, Siti M I, Ankathil R & Zilfalil B A, " Two cases of Isochromosome 18q syndrome", Singapore Medical Journal 2007; 48(5) : e146

4) TRISOMY 18 – Edwards syndrome, Centre for Genetics Education

http://www.genetics.edu.au