Handbook of Genetic Counseling/Turner Syndrome

Turner Syndrome

(Ullrich-Turner syndrome or Bonnevie-Ullrich-Turner syndome)

Incidence

• 1/2,500 - 1/5,000 liveborn females based on screening newborn pop.
• perhaps 1% -2% all conceptions (occurs more often in preg. losses)
• 95-99% miscarried most in 1st trimester
• usually sporadic not associated with AMA
• recurrence risk not increased for subsequent pregnancies

Prognosis

• Prematurity more common in preg. with Turner
• mean birth weight in full term between 25-50 %ile
• mean length in 5%ile of normal female
• by 18 mths most growing at or below 3%ile height
• Most consider standard of care to treat with growth hormone (although not deficient) differences in height appear to be a few centimeters (some studies not confirm this)
• most adults adjust to petite stature
• Feeding problems common including freq. spitting, vomiting and difficulty sucking and latching on also can have gastroesophageal reflux and failure to thrive
• Obesity can be problem in later childhood and adult (excess calorie intake decrease expenditure -- short girls less likely to physical activity not intrinsic metabolic abnormality

Treatment/screening

• encourage physical activity
• educate about nutrition
• hormone replacement (family informed decision appears safe, but not much long-term data) begin at age 4
• treat age appropriately not according to height
• annual echo recommended
• begin at years thyroid function screening every other year and yearly in adults
• periodic urinalysis for glucose
• ovarian hormone therapy initiated at about 14 years
• eye exam in infancy and refer at any time if concerns

Life expectancy

• one population 156 with Turner's found 5 fold increase (15 deaths) in death rate over expected and 3 fold when congenital heart disease excluded
• series of 500 liveborn patients, 25 died 10 due to complications of CHD.
• Among 215 adults 5 cardiac, 2 accident, 1 malignant hyperthermia, 1 AML, 1 acute febrile syndrome, 3 old age

Physical Features

• short stature
• high arched palate
• prominent ears
• webbing of neck
• low posterior hairline:trident configuration
• increased carrying angle of arm
• puffy hands and feet (lymphedema) may take months to several years to go away
• hypoplastic nail beds
• multiple pigmented nevi

Possible Health Concerns

• frank gastroesophageal reflux and failure to thrive also noted
• ear infections and sensorineural hearing loss is seen
• structural renal malformations found in ~40%: horseshoe kidney, duplication of ureters
• minority can have recurrent UTI and hydronephrosis
• cardiac anomalies: estimated 17-45% coarctation of aorta, bicuspid aortic valve, hypoplastic left heart, VSD (risk of aortic dissection may be increased)
• hypertension and mitral valve prolapse
• streak gonads w/ absent oocytes, normal uterus but may be small
• 90% require estrogen to initiate puberty and est. progest. to maintain menses
• lack pubertal development and no onset of menses (97%)
• infertility 99%
• frequent dislocation of patella and knee pain common
• Increased incidence of autoimmiune disorders
• hypothyroidism common 15-30% of adults

Development and Behavior

• Usually have ave IQ within normal range shifted to left 10-12 points, compared to sibs
• ~10% have significant delays need special education and may need ongoing assistance in adult life with job or living
• discrepancy between verbal and performance IQ (verbal usually normal performance 10-12 points lower)
• visual spatial weaknesses: copy designs, memory visual patterns, left-right directions, math
• some studies show increased anxiety in younger girls, social withdrawal and depression in older girls
• Some girls may have hyperactivity, immature behavior, difficulty focussing
• later to date, leave home, and marry than age-matched cohorts
• surveys show: most well educated, most function in employment BUT problems with methodology

Reproductive options

• IVF with donor oocytes (has been successful) expensive not always covered by insurance > 230 pregnancies in 93 women (1995) risk of SA (if fertile higher risk of trisomy 21)
• adoption

Possible psychosocial concerns

• difficulty having a child with multiple medical problems
• balancing the care of two children can be difficult anyway without added concerns
• disappointment at prospect of child not being able to have biological children

Resources

• http://www.turner-syndrome-us.org/ (website for the Turner's Syndrome Society of the U.S.)

References

• Health Supervision for Children With Turner Syndrome. American Academy of Pediatrics Policy statement. December, 1995, p 1166-1173
• Sybert VP (2001). Turner Syndrome. Management of Genetic Syndromes. Editors Cassidy SB, Allanson JE. Wiley-Liss, Inc.

Notes

The information in this outline was last updated in 2001.