Congenital Abnormalities Flashcards
What causes most of spontaneous abortions in recognized pregnancies?
Gross structural abnormalities
Whats the difference between major and minor abnormalities?
Major has adverse outcome on the function (clinical) acceptability or soccial acceptability of the individual, minor does not
Define a malformation
Primary structural defect of an organ or parts of it that results in an inherent abnormality in development. The early development of the oran has been arrested or misdirected
What are some examples of malformations?
Cleft lip/palate or cardiac malformations
What causes single organ malformations?
Multifactorial inheritance
What causes multiple organ malformations?
Chromosomal abnormalities or single gene mutations
What is a disruption? What is it also known as?
Abnormal structure of an organ or tissue as a result of external factors disrupting the normal developmental process. AKA secondary or extrinsic malformation
Are disruptions genetic?
Not usually genetic
What are some examples of disruptions?
Ischemia, infection, trauma
What are amniotic bands?
A disruption that develops when a strand of amnion becomes entwined around a fetus’ limb or digit
What is deformation? When do they usually occur?
Defect resulting from an abnormal mechanical force that distorts an otherwise normal structure. Usually occur late in pregnancy
What can cause deformation? Can it be fixed?
Reduced amniotic fluid, intrauterine crowding or, a structurally abnormal uterus. The underlying organ can usually be treated
What is an example of deformation?
clubfoot
What is dysplasia and where does is manifest?
Abornmal organization or assembly of cells into tissues and it manifests in a specific tissue
What can dysplasia predispose you to later on in life?
Cancer
What is dysplasia’s inheritance pattern?
Genetic inheritance with a high recurrence risk in relatives of affected individuals
What causes ectodermal dysplasia? What tissues does it affectt?
Mutations on genes involved with signaling mesoderm and ectoderm leading to dysfunctional ectoderm. Hair teeth skin nails
What is a sequence?
Findings that occur as a consequence of a cascade of events initiated by a single factor
What is potter sequence?
Chronic leakage of fluid causing oligohydramnios - the decrease of amniotic fluid
What does the potter sequence result in?
Clubbed feed, hip dislocation, facial features, pulmonary hypoplasia
What is a syndrome?
Consistent and recognizable patterns of abnormalities for which there often is a known underlying cause
What abnormalities are associated with Down Syndrome?
Low IQ, congenital heart and GI tract defects, epicanthic folds, broad nasal bridge, short stature
What is an association? How are they named?
Malfunctions that tend to manifest in clusters more frequently than wold be expected by chance. Lack of consistency of abnormalities and no underlying explanation. Names are often acronyms
VACTERL patients need at least 3 of what signs?
Vertebra defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal and limb abnormalities
Environment can disrupt development by interfering with what devlopmental processes
Gene expression, cell prolferation, differentiation, migration and morphogenesis
Prenatal exposure to alcohol results in FAS, what effects does it have?
Characteristic facial anomalies, growth retardation, CNS involvment in the form of cognitive impairment, learning disabilities or behavioral abnormalities
What are the signs of FAS?
Mental retardation, behavior impairment, attention deficit, epicanthal folds, thin upper lip, hypoplastic nose, smooth philtrum, micrognathia
What drug caused phocomelia and how did it do it?
Thalidomide interferes with the formation of blood vessels
What is phocomelia?
Limb malformations
How does Zika virus affect fetus?
Infects neural stem cells in a developing fetus affecting their proliferation, growth, differentiation which ultimately impairs normal development of the nervous system
What severe sign can zika virus cause?
Severe microcephaly