Teratology Flashcards
What is considered a minor anomaly in teratology?
Are not themselves detrimental to health
(i. e. small ears, pigment spots)
- occur in ~15% of newborns
Minor anomalies serve as clues for diagnosing more serious defects
What are causes of birth defects?
- Genetics
- Environmental Teratogens
- -> Infectious agents
- -> physical agents
- -> chemicals agents
- -> hormones
What are the two groups of anomalies?
- Syndrome
- Group of anomalies that occur together from a specific common cause
- cause has been determined
- risk of recurrence is known - Association
- non-random appearance of anomalies
- cause has not been determined
What are the principles of teratology?
- Genotype of conceptus determines susceptibility of teratogenesis
- Susceptibility to teratogens varies depending on development age of exposure
- Dose and duration of exposure to teratogen determines manifestations of abnormal development
- Teratogens act in specific ways on developing cells/tissues to initiate abnormal development
- Manifestations of abnormal development are:
Death
Malformation
Growth Retardation
Functional Disorders
When is the conceptus most susceptible to teratogens?
During the period of embryogenesis
–> may be one or more stages of susceptibility
- no stage is completely safe
What infectious agents are considered teratogens?
TORCH
Toxoplasma
Rubella
Cytomegalovirus
HSV
Elevated body temperature - infections with fever can cause birth defects
What teratogen is concurrent with the following congenital malformations:
Cataracts
glaucoma
heart defects
deafness
tooth abnormalities
Rubella virus
What teratogen is concurrent with the following congenital malformations:
Often fatal
If not, includes:
microcephaly
blindness
mental retardation
Cytomegalovirus
What teratogen is concurrent with the following congenital malformations:
Micropthalmia
microcephaly
retinal dysplasia
HSV
What are the key features of Congenital Rubella Syndrome (CRS)?
- Replication of virus in throat for weeks
- high levels of virus present
- viral infection of the placenta
- All cells in fetus infected after maternal viral infection
- Confirmed rubella during 1st trimesster
What teratogen is concurrent with the following congenital malformations:
Anencephaly
Spina bifida
mental retardation
facial defects
cardiac abnormalities
limb defects
Hyperthermia
What teratogen is concurrent with the following congenital malformations:
Microcephaly
Spina Bifida
Cleft palate
limb defects
X-rays
What teratogen is concurrent with the following congenital malformations:
Limb defects - loss of long bones
heart malformations
Thalidomide
What teratogen is concurrent with the following congenital malformations:
Cleft lip and palate
heart defects
Amphetamines
What teratogen is concurrent with the following congenital malformations:
Growth retardation
microcephaly
addiction
Cocaine