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Sections Genetics of Achondroplasia
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Workup
Treatment
Medication
Follow-up
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References

Follow-up

Further Outpatient Care

The following recommendations for the medical management and follow-up care of patients with achondroplasia were presented at the First International Symposium on Human Achondroplasia held in Rome, Italy, in 1986:

Height, weight, and head circumference measurements plotted on growth curves standardized for achondroplasia
Thorough neurologic examinations for clinical assessment; CT scanning, MRI, somatosensory-evoked potentials, and polysomnography as indicated for clinical findings of concern
Appropriate medical care for recurrent middle ear infections; referral to otolaryngologist if concern for conductive hearing loss due to chronic serous otitis media
Dentistry and orthodontics to address dental crowding associated with the craniofacial features seen in achondroplasia

Complications

Complications include cervicomedullary compression, spinal stenosis, restrictive and obstructive lung disease, otitis media, and tibial bowing. Other possible complications include the development of thoracolumbar kyphosis, symptomatic hydrocephalus, and symptomatic upper cord compression.

Prognosis

Most patients diagnosed with achondroplasia have normal intelligence, lead independent and productive lives, and have a normal life expectancy. However, infants and children below age 2 years have some increased risk for early death when compared with the general population. Without proper assessment and medical care, 2-5% of children with achondroplasia will die. Most of this increased risk is due to craniocervical junction abnormalities.

Patient Education

Genetic counseling is recommended to discuss the genetics of cause, recurrence risk, and prenatal diagnosis with families.

Patient education guidelines

Age-related care guidelines have been provided in "Health Supervision for Children with Achondroplasia" by the American Academy of Pediatrics, Committee on Genetics, published in September 2005.^[36]

Prenatal visits

Geneticists (genetic counselors and medical geneticists), obstetricians, and pediatricians should be consulted to educate parents regarding the disorder, inheritance, and prognosis for offspring.

Infants (0-12 mo)

Review the personal support available to the family.

Review contact information for support groups.

Review the increased risk of serous otitis media due to shortened eustachian tubes. Instruct that otic examination is needed with any upper respiratory tract infection.

Avoid infant carriers that place the infant in a curled-up position. Car safety seats should always be used during automobile travel.

Early childhood (1-5 y)

Discuss adapting the home so that the child can become independent (lower the height of light switches and supply step stools).

Discuss adapting age-appropriate clothing with snapless easy-opening fasteners and tuckable loops.

Discuss adaptation of toys, especially tricycles, to accommodate for shorter limbs.

Discuss adaptation of toilets to allow comfortable independent use, with an extended wand to clean soiled areas.

Discuss the use of a foot-support stool during sitting so that the child's feet are not hanging. Foot support is needed while the child is sitting in a chair. A cushion behind the child's back may be required for good posture.

Discuss orthodontics and the possible need for braces in children older than 5 years.

Encourage the family to develop activities in which the affected child can take part; avoid gymnastics, high diving, acrobatics, and collision sports.

Discuss how to talk with the child, friends, and family members about short stature.

Encourage preschool attendance so that the child can learn to socialize in an age-appropriate way.

Discuss with school staff, toileting procedures and special preparations as needed, due to the child's short stature

Discourage the child from high jump activity to minimize stress on the joints and spine.

Late childhood (5-13 y)

Children with achondroplasia usually have normal intelligence and are matriculated in the regular education program.

Discuss the need to prepare school personnel and to supply proper furnishings to accommodate for the child's stature.

Prepare the child for psychosocial situations, and teach the child how to address these issues.

Help children explain their short stature to their peers and encourage them to ask for assistance, if needed.

Suggest adaptive aids in the school to help the child cope with heavy doors, high doorknobs, blackboard use, and a regular-sized desk, and stress the need for proper foot support.

Ensure that the child can use the restroom independently.

Adolescence to early adulthood (13-21 y)

Revisit the patient’s diagnosis to ensure that the adolescent has an understanding of his or her diagnosis and of the genetic etiology of achondroplasia.

Discuss contraception and the options available. Women of reproductive age with achondroplasia are fertile, and, as such, potential for pregnancy complications and outcomes should be addressed.

Continue nutritional counseling to address the importance of weight management. Stress eating habits that minimize the risk of obesity and the comorbid complications associated with excessive weight gain.

Assist the patient to establish an independent lifestyle. Fostering the ability to obtain a driver's license can help. Drivers require certain vehicle modifications, such as pedal extenders. The Association for Driver Rehabilitation Specialists (ADED) helps those who have certain transportation needs and vehicle adaptations.

Support organizations

Support groups may help (1) provide practical information to address potential problems in daily living and having disproportionate short stature and (2) provide emotional and psychosocial support to patients, parents, and caregivers living with achondroplasia.

National Headquarters Little People of America, Inc.

250 El Camino Real, Suite 211

Tustin, California 92780

Toll-free: (888) LPA-2001

Direct: (714) 368-3689

Fax: (714) 368-3367

E-mail: info@lpaonline.org

Website: www.lpaonline.org

March of Dimes (MOD)

National Office

1275 Mamaroneck Avenue

White Plains, NY 10605

Phone: (914) 997-4488

Web site: www.marchofdimes.com

Human Growth Foundation (HGF)

997 Glen Cove Avenue, Suite 5

Glen Head, NY 11545

Toll-free: 800-451-6434

FAX 1-516-671-4055

Website: www.hgfound.org

International Skeletal Dysplasia Registry

Phone: 1-800-CEDARS-1 (1-800-233-2771)

Web site: www.csmc.edu

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Media Gallery

Height for females with achondroplasia (mean/standard deviation [SD]) compared to normal standard curves. The graph is based on information from 214 females. Adapted from Horton WA, Rotter JI, Rimoin DL, et al. Standard growth curves for achondroplasia. J Pediatr. 1978 Sep; 93(3): 435-8.
Height for males with achondroplasia (mean/2 standard deviations [SDs]) compared to normal standard curves. The graph is based on information from 189 males. Adapted from Horton WA, Rotter JI, Rimoin DL, et al: Standard growth curves for achondroplasia. J Pediatr. 1978 Sep; 93(3): 435-8.
Mean growth velocities (solid line) for males (top) and females (bottom) with achondroplasia compared to normal growth velocity curves. Dashed lines indicate third percentile, mean, and 97th percentile. Data are from 26 males and 35 females. Adapted from Horton WA, Rotter JI, Rimoin DL, et al. Standard growth curves for achondroplasia. J Pediatr. 1978 Sep; 93(3): 435-8.
Upper and lower segment lengths for males (top) and (bottom) with achondroplasia (mean/standard deviation [SD]). Data are from 75 males and 95 females. Adapted from Horton WA, Rotter JI, Rimoin DL, et al. Standard growth curves for achondroplasia. J Pediatr. 1978 Sep; 93(3): 435-8.
Head circumference for females with achondroplasia compared to normal curves (dashed lines). Data are from 145 females. Adapted from Horton WA, Rotter JI, Rimoin DL, et al. Standard growth curves for achondroplasia. J Pediatr. 1978 Sep; 93(3): 435-8.
Head circumference for males with achondroplasia compared to normal curves (dashed lines). Data are from 114 females. Adapted from Horton WA, Rotter JI, Rimoin DL, et al. Standard growth curves for achondroplasia. J Pediatr. 1978 Sep; 93(3): 435-8.