Congenital anomalies

Question 1

Define a congenital malformation.

Answer 1

A structural defect present at birth

Question 2

What are the factors that lead to congenital malformations?

Answer 2

Hereditary (genetic/chromosomal factors)
Environmental
(Interaction of genetic and environmental factors

Question 3

Heart defects, Cataracts, Glaucoma (blindness due to pressure in eyeballs), and Deafness are characteristic abnormalities of which environmental agent?

Answer 3

Rubella virus/German measles

Question 4

What possible abnormalities can be brought about by exposure of developing embryo/fetus to HIV?

Answer 4

Microcephaly (small head)

Growth retardation

Question 5

How do infectious agents cause malformations?

Answer 5

Many of them are pyrogenic (they cause fever/hyperthermia); the hyperthermia causes malformations

Question 6

Give 3 examples of numerical chromosomal abnormalities.

Answer 6

Down’s Syndrome/Trisomy 21
Turner syndrome/Missing one X chromosome in females
Klinefelter syndrome/Having 2 X chromosomes in males

Question 7

Give 3 examples of structural chromosomal abnormalities.

Answer 7

Cri-du-chat syndrome/ Deletion of genetic material on Chromosome 5
Angelman syndrome/ Deletion/Absence of UBE3A gene on maternal chromosome
Prader-Willi syndrome/Deletion of a gene on paternal chromosome

Question 8

What are the phenotypes of Down’s syndrome?

Answer 8

Only 1 palmar transverse crease 
Lazy eyes 
Bent pinky finger 
Thick skin on palms, soles, and back of neck
Intellectual disability

Question 9

State the symptoms of Angelman’s syndrome.

Answer 9

Abnormally small head
Widely spaced teeth, mouth, and nose 
Frequent laughter and smiling 
Hyperactive
Crossed eyes

Question 10

How does Turner syndrome present?

Answer 10

Lack of menstruation
Late development 
Short stature/height 
Obesity 
Wide-spaced nipples 
Congenital heart defects 
Recurrent ear infections
Webbed neck

Question 11

What is the phenotype of Cri-Du-Chat syndrome?

Answer 11

Cat-like cry when infant
High pitched voice
Severe mental retardation

Question 12

What proportion of conceptions end in spontaneous abortion?

Answer 12

50%

Question 13

What is a major cause that accounts for 50% of the spontaneous abortions?

Answer 13

Major chromosomal abnormalities

Question 14

A pregnant patient comes with severe hemorrhaging in the second month. She may have experienced _________.

Answer 14

an ectopic/extrauterine pregancy

Question 15

What is a primary ovarian pregnancy?

Answer 15

Development of blastocyst in ovary wall

Question 16

Where in the abdominal cavity does the embryo normally attach?

Answer 16

Douglas’s pouch/ Peritoneal Lining of Retouterine cavity

Question 17

Define abortion

Answer 17

The premature exit of the products of conception (the fetus, fetal membranes, and placenta) from the uterus

Question 18

Define anencephaly

Answer 18

Congenital defect in which part of the brain and the bones around it do not form; caused by neural tube failing to close at the cranial neuropore around day 24

Question 19

Define microcephaly

Answer 19

A smaller head than usual caused by incomplete development of the brain

Question 20

What are the causes of microcephaly?

Answer 20

Malnutrition
Lack of oxygen to brain
Chromosomal abnormalities ex: Down’s syndrome, Angelman’s syndrome

Question 21

What are increased levels of AFP (alpha-fetoprotein) related to?

Answer 21

Neural tube defects

Gut abnormalities

Question 22

When can AFP (alpha-fetoprotein) maternal screening test be done?

Answer 22

When embryo is around 14 days old

Question 23

What classification does an abnormality fall into if it occurs during organogenesis?

Answer 23

Malformation

Question 24

Differentiate malformation, deformation, and disruption.

Answer 24

Malformation - occurs in embryonic phase during formation of structures
Deformation - occurs in late fetal phases, a result of mechanical force applied to normally developing or already developed structures
Disruption - can occur at any time, a result of destructive force (ex; virus or mechanical force) on an already-formed and developing structure that is normal

Question 25

At which stage of gestation do deformations usually occur?

Answer 25

Late fetal stage

Question 26

What is placenta abruption?

Answer 26

when placenta detaches from uterus