Information on the following diseases can be found in the Related Disorders section of this report:

• Chondroectodermal Dysplasia
• Diastrophic Dysplasia
• Metrophic Dwarfism
• Short Rib Polydactyly Syndrome (Types I, II, III, IV)

Asphyxiating Thoracic Dystrophy (ATD) is characterized by insufficient growth of the rib cage (thorax) in newborns. The characteristic "bell-shaped" chest cavity results in the inability of the infant to breathe properly. Lung infections, high blood pressure, pancreatic cysts and the growth of too many fingers and toes (polydactyly) may also occur. ATD patients may also have insufficient growth of the pelvic bones and shortened long bones of the arms and legs. Breathing and kidney problems are the most serious complications of ATD.

The immediate problem in asphyxiating thoracic dystrophy is the hardening of the endochondral bone in the fetal rib cage (thorax). Beneath this physical problem is a genetic cause, and although it is clear that asphyxiating thoracic dystrophy is inherited as an autosomal recessive trait, the faulty chromosome and the location of the defective gene have not yet been established.

Chromosomes, which are present in the nucleus of human cells, carry the genetic information for each individual. Human body cells normally have 46 chromosomes. Pairs of human chromosomes are numbered from 1 through 22 and the sex chromosomes are designated X and Y. Males have one X and one Y chromosome and females have two X chromosomes. Each chromosome has a short arm designated “p” and a long arm designated “q”. Chromosomes are further subdivided into many bands that are numbered. For example, “chromosome 11p13” refers to band 13 on the short arm of chromosome 11. The numbered bands specify the location of the thousands of genes that are present on each chromosome.

Genetic diseases are determined by the combination of genes for a particular trait which are on the chromosomes received from the father and the mother.

Recessive genetic disorders occur when an individual inherits the same one normal gene for the same trait from each parent. If an individual receives one normal gene and one gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. The risk for two carrier parents to both pass the defective gene and, therefore, have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%. The risk is the same for males and females.

All individuals carry 4-5 abnormal genes. Parents who are close relatives (consanguineous) have a higher chance than unrelated parents to both carry the same abnormal gene, which increases the risk to have children with a recessive genetic disorder.
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The incidence of asphyxiating thoracic dystrophy is about 1 in 100,000 to 130,000 live births. Males and females appear to be affected in equal numbers, as do persons of various ethnic or racial backgrounds.
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Symptoms of the following disorders can be similar to those of asphyxiating thoracic dystrophy. Comparisons may be useful for a differential diagnosis.

Chondroectodermal dysplasia features dwarfism with striking shortening of the extremities. Extra fingers and toes, fused wrists, dystrophy of the fingernails, lip abnormalities, and heart defects also occur in this disorder.

Metatrophic dwarfism is noticed in infancy, and is characterized by the development of a long narrow thorax, flattening of the vertebral bones and relatively short limbs. Progressive deformity of the bones of the thorax and spine causes a loss of pervious development of normal body proportions. This results in short-spine dwarfism with severe dysplasia of the skeleton.

Diastrophic dysplasia is a relatively common form of dwarfism characterized by short limbs and often complicated by cleft palate, clubfeet, hitchhiker thumb and/or cauliflower ears. Although breathing problems may be present at birth and continue thereafter, life expectancy is normal.

Short rib-polydactyly syndrome describes a group of four lethal skeletal dysplasias characterized by an undersized (hypoplastic) thorax, short ribs, short limbs, multiple fingers and toes (polydactyly), and abdominal (visceral) abnormalities. All of the variants are thought to be inherited in an autosomal recessive pattern.
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Diagnosis
The presentation and severity of asphyxiating thoracic dystrophy may vary considerably. Even the degree of difficulty in breathing may vary from life-threatening failure to the apparent absence of distress at all.

Prenatal diagnosis is now possible through ultrasound imaging. A combination of breathing difficulties in the presence of a small, narrow chest, along with obvious shortened limb development, is usually sufficient for a diagnosis.

Treatment
The titanium rib developed by Robert Campbell, MD, and colleagues at the Santa Rosa Children's Hospital in San Antonio was approved by the U.S. Food and Drug Administration in 2005 for the treatment of children with thoracic insufficiency syndrome resulting from Jeune's syndrome and related conditions. For information on the titanium rib, write to lori.buegeler@christushealth.org, case manager, or contact Dr. Campbell:

Robert Campbell, M.D.
Santa Rosa Children's Hospital
519 West Houston Street
San Antonio, TX 78207

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government website.

For information about clinical trials being conducted at the National Institutes of Health (NIH) Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222
TTY: (866) 411-1010
Email: prpl@cc.nih.gov

McKusick VA, Ed. ONLINE MENDELIAN INHERITANCE IN MAN (OMIM). The Johns Hopkins University. Entry Number; 2085000: Last Edit Date; 12/8/2001

TEXTBOOK
Campbell RM Jr. Asphyxiating Thoracic Dystrophy. In: NORD Guide to Rare Disorders. Lippincott Williams & Wilkins. Philadelphia, PA. 2003:155-56

Jones KL. Ed. Smith’s Recognizable Patters of Human Malformation. 5th ed. W.B. Saunders CO., Philadelphia, PA; 1997:292-95

JOURNAL ARTICLES
Campbell RM Jr., Smith MD, Mayes TC, et al. The characteristics of thoracic insufficiency syndrome associated with fused ribs and congenital scoliosis. J Bone Joint Surg. 2003;85:399-408

Campbell RM Jr., Hell-Vocke AK. Growth of the thoracic spine in congenital scoliosis after expansion thoracoplasty. J Bone Joint Surg. 2003;85:409-420.

Das BB, Nagaraj A, Fayemi A, et al. Fetal thoracic measurements in prenatal diagnosis of Jeune Syndrome, Indian J. Pediatr. 2002;69:101-03

Kaddoura IL, Obeid MY, Mrouch SM, et al. Dynamic thoracoplasty for asphyxiating thoracic dystrophy. Ann Thorac Surg. 2001;71-1755-58

Ho NC, Francomano CA, van Allen M. Jeune asphyxiating thoracic dystrophy and short-rib polydactyly type III (Verma-Naumoff) are variants of the same disorder. Am J Med Genet. 2000;90:310-14.

Aronson DC, Van Nierop JC, Taminlau A, et al. homologous bone graft for expansion thoracoplasty in Jeune’s asphyxiating dystrophy. J. Pediatr Surg. 1999:34:500-03

Labrune P, Fabre M, Trioche P, et al. Jeune syndrome and liver disease: report of three cases treated with ursodeoxycholic acid. Am J Med Genet. 1999;87:324-28

Sarimurat N, Elcioglu N, Tekant GC, et al. Jeune’s asphyxiating thoracic dystrophy of the newborn. Eur J Pediart Surg. 1998;8:100-01

Chen CP, Lin SP, Liu FF, et al. Prenatal diagnosis of asphyxiating thoracic dysplasia (jeune syndrome). Am J Perinatol. 1996;13;495-95

Davis JT. Lateral thoracic expansion for Jeune’s asphyxiating thoracic dysplasia. Ann thorax Surg. 1995:60:694-96.

Yang SS, Heidelberger KP, Brough AJ, et al. Three Conditions in neonatal asphyxiating thoracic dysplasia (Jeune) and short rib polydactyly syndrome spectrum: a clinicopathologic study. AM J Med Genet. 1987;3 (Suppl):191-207.

Oberklaid F, Danks FM, Mayne V, et al. Asphyxiating thoracic dysplasia. Clinical radiological, and pathological information on 10 patients. Arch Dis Child. 1977;52:756-65.

FROM THE INTERNET
Chen H. Asphyxiating Thoracic Dystrophy. (Jeune Syndrome) eMedicine. Last Updated: December 13, 2002: 10pp.
http://www.emedicine.com/ped/top1224.htm

Asphyxiating thoracic dysplasia. Medcyclopedia. Nd. 1p
www.amershamhealth.com/medcyclo…/ASPHXIATING%20THORACIC%20DYSPLASIA

Jeune’s Syndrome. Medcyclopedia. Nd.1 www.amershamhealth.com/medcyclopedia/Volumer%20III%20jeunes%20syndrome.asp