Handbook of Genetic Counseling/Russell Silver Syndrome

Russell Silver Syndrome

Introduction

 * Introductions
 * What do you understand about why you are coming to genetics?
 * What specific questions would you like to have answered today?
 * Outline what will happen in session:
 * Take medical and family history
 * Doctor will perform physical exam
 * Discussion and answer further questions

Obtain Medical History

 * Thorough pregnancy history
 * History of maternal hypertension
 * Teratogenic exposures
 * Intrauterine infections

Obtain Family History

 * Birth weights and heights of parents and siblings

Genetics

 * Etiology is widely variable
 * 10% of patients have maternal UPD of chromosome 7
 * autosomal dominant and autosomal recessive forms have also been seen
 * some evidence for AD gene located on long arm of chromosome 17

Clinical Features

 * Growth and Feeding
 * IUGR with weight less than 3SD below mean for gestational age
 * Birth length also diminished
 * Normal head circumference
 * Usually difficult to feed
 * GERD and delayed gastic empting are prevelent GI disorders
 * Normal growth velocity
 * Remain small into adulthood
 * Most do not have growth hormone deficiency
 * Development and Behavior
 * Normal IQ
 * Early gross motor delay
 * Mild hypotonia
 * Many patients have learning disabilities
 * Craniofacial
 * Dental anomalies common including microdontia
 * Micrognathia is common
 * Can cause secondary cleft palate
 * Musculoskeletal
 * Limb length asymmetry
 * No cancer related to asymmetry has been reported
 * Genitourinary
 * Cryptorchidisim
 * Hypospadias
 * Occasional renal anomalies

Diagnosis

 * Minimal diagnostic criteria includes
 * IUGR
 * Postnatal growth retardation
 * Normal head circumference
 * Triangular face
 * Fifth finger clinodactyly
 * Normal psychomotor development
 * Supportive criteria
 * Short arm length
 * Limb length asymmetry
 * Cryptorchidism
 * Hypotonia
 * Normal intelligence
 * Diagnostic Testing
 * Microsatellite analysis of chromosome 7

Differential Diagnosis

 * Any condition that can include IUGR
 * Many chromosomal disorders
 * Deletion distal arm chromosome 15
 * MR, microcephaly, non triangular face
 * Chromosome breakage syndromes
 * Fanconi anemia, Nijmegen immunodeficiency syndrome, and Bloom syndrome
 * Tend to have microcephaly
 * Fetal Alcohol syndrome
 * X-linked short stature with skin pigmentation
 * 3-M syndrome
 * skeletal changes, no triangular face

Surveillance and Treatment

 * growth hormone for those with deficiency
 * early intervention for learning disabilities
 * evaluation and treatment limb asymmetry depending on severity
 * lift in shoe during growth
 * bone lengthening when growth is finished
 * epiphysiodesis

Psychosocial Issues

 * How have you been dealing with this?
 * How would having this diagnosis change care?
 * What other ways will having this diagnosis be beneficial?
 * Have you had any trouble with insurance?
 * Are you considering having other children?
 * Have you had all your questions answered?

Resources

 * Association for Children with Russell-Silver Syndrome, Inc.
 * 22 Hoyt St.
 * Madison, NJ 07940
 * Phone: (201) 377-4531
 * Fax: (201) 822-2715


 * Russell-Silver Support Group (MAGIC Foundation)
 * 1327 N Harlem Ave.
 * Oak Park, IL 60302
 * (313) 586-8038
 * (800) 3-MAGIC-3
 * email: slantana@awol.com
 * website: http://www.nettap.com/~magic/


 * National Organization for Rare Disorders, Inc. (NORD)
 * P.O. Box 8923
 * New Fairfield, CT 06812-8923
 * (203) 746-6481
 * TDD: (203) 746-6481
 * Email: orphan@nord-rdb.com