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

References

• Saal, HM. "Chapter 20: Russell-Silver Syndrome." Management of Genetic Syndromes. Edited by Suzanne B. Cassidy and Judith E. Allanson. 2001.
• Geneclinics: Russell-Silver Syndrome

Notes

The information in this outline was last updated in 2002.