# 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.