Clinical Dysmorphology Flashcards
what are congenital anomalies?
any aberrant structural feature present at birth - not all congenital anomalies are genetic
what is dysmorphology? and how does it differ from teratology?
the study of abnormal morphogenesis, abormal physical development, congenital anomalies and syndromes -> abnormal human development
**very strong genetic component while teratology has a very strong environmental component
what are some common etiologies of abnormal development?
chromosomal, single gene, multifactorial (genes + environment), epigenetic (DNA sequence has been altered by means other than chemical), and environmental
what is the importance of the Hapsburg lip and jaw (the european royalty family)?
normal variation can be pathogenic, especially with consanguinity
what is the difference between disorders and age wrt parental sex?
increase maternal age, increase chance of aneuploidy
increase paternal age (esp above age 32), increase chance for dominant genetic disorders (linear association)
when physically examining a patient for dysmorphic features and congenital anomalies, what do you do (4 things)?
- observe dysmorphic features (also how patient interacts with the environment)
- measure when appropriate
- quantitate findings whenever possible (measure, measure, measure)
- photograph anything of interest (with permission)
what is the difference between malformation, deformation and disruption? when are these terms used?
malformation: abnormal formation of tissue
deformation: unusual forces on normal tissue
disruption: breakdown of normal tissue
these terms are used for single congenital anomalies
what are common congenital deformations?
head and neck: cranial molding,mandibular asymmetry, external ear deformities
limbs: clubfoot, crowded/overlapping toes, tibial torsion, joint dislocation
nerve compression: facial nerve palsy, Erb’s palsy
What are two causes of common congenital birth defects of disruption? (list cause and the birth defects)
Vascular disruption/ischemia: OAV (one side of the face is underdeveloped…disruption of blood supply to developing branchial arches), gastroschisis, ileal atresia, porencephalic cysts
early amnion rupture/amniotic bands: cranial anomalis, facial clefts, absent limbs or digits, anterior abdominal wall defects
What are the findings of OAV?
OAV: caused by disruption of blood supply to developing branchial arches
findings: ocular, auricular, vertebral, and cardiac anomalies with facial asymmetry
there is a spectrum
What is the difference between sequence, syndrome and association? what types of anomalies are they associated with?
syndrome: a primary developmental anomaly of 2+ systems due to a common etiology
association: a non-random recurring pattern of malformations with no defined etiology
sequence: a pattern of malformations due to a cascading effect from a single minor alteration early in morphogenesis….implies that timing is very important
What is the Pierre Robin anomaly?
deals with SEQUENCE (there is a single localized anomaly early in morphology that leads to many secondary characteristics)…the single primary anomaly is micrognathia (jaw is undersized)
the cleft of the palate will be U shaped and the tongue will be displaced posterior and superior
