Approach to the Patient With Multiple Congenital Abnormailities Flashcards
Dysmorphology
Term used to describe variability in both normal and abnormal physical traits
Malformations due to
Intrinsically abnormal developmental process
When do malformations often occur
Embryologic development (Prior to Week 8)
What can cause malformatiosn
Genetic or environmental forces
Synpolydactyly
Extra fingers, toes, with some fused together
Mutations to homeobox of HOXD13 gene
Retinoic acid can cause
Malformations such as Hydrocephalus
Metabolite of vitamin A
Molecular mechanisms involved in major malfomrations
Apoptosis, abnormal signaling, chromatin modeling
Infants with how many minor malformations at greater risk for major/syndrome
3 or more
20-25%
Deformations caused by
Extrinsic intrauterine mechanical forces
Fatal fetal compression a result of
A deformation
Example of forces of deformations
Decreased amniotic fluid, uterine tumors, uterine malformations
Deformations also caused by
Uterine corowing if multiple gestations
ABS
Amniotic band syndrome
Group of structural abnormalities mostly in limbs but also sometimes in craniofacial area
Amniotic bands are
Fibrous bands that can constrict fetal parts
Dysplasias
Abnormal organization of cells in tissues
Achondroplasia
Dwarfism
Example of a dysplasia
Unusual bone growth
Cause by mutation in fibroblast growth factor receptor 3 gene
Common deformations
Club foot, plagiocephaly
Syndrome
Pattern of anomalies that occur together and are pahtogenetically related
Turner syndrome
Monosomy of X chromosome
Short stature, webbed neck, swollen hands and feet
Marfan syndrome - inhertiance and mechanism
Auto dominant
Mutations of FBN 1 gene
FBN1 encodes fibrillin 1…fibrillin 1 is a glycoprotein important for maintaining structural intergrity of conective tissue
Sequences
Pattern of anomalies in which a single defect in development causes a cascade of abnormalities
Potter sequence
Caused by oligohydramniois secondary to renal anomalies
Result of potter sequence
Restricts movement so flat face, depression of nasal tip, abnormal ear folding, wrinkled skin, and malposition of feet
What is associated with Potter sequence
Decreased urine output
Oligohydramnios (could also be from renal agenesis)
Pulmonary hyperplasia