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Types of anomalies

Q: What are developmental anomalies?

Developmental anomalies are irreversible structural or functional anomalies that occur during intrauterine life .

Q: In what body regions are Minor Congenital Anomalies most common?

Areas of complex development — hands, feet, face, ears.

Q: What does the presence of multiple minor anomalies indicate?

It may signal an underlying major congenital anomaly.

27 important questions on Types of anomalies

What are developmental anomalies?

Developmental anomalies are irreversible structural or functional anomalies that occur during intrauterine life.

When can developmental anomalies be identified?

They can be identified prenatally, at birth, or sometimes later in infancy

Why are not all organs/systems equally sensitive at a given time?

Because the sensitivity of organs/systems at a time depends on timing, teratogens, and consequences

What percentage of infant deaths are linked to birth defects?

20% of infant deaths are linked to birth defects

What are Normal Variants in developmental anomalies?

Variations seen in more than 4% of the general population that are unlikely to be associated with other anomalies.

What are some examples of normal variant developmental anomalies?

mild frontal hair sweep, mild fusion of 2–3 toes

Are Normal Variants considered harmful or clinically significant?

What are Minor Congenital Anomalies?

Developmental anomalies present in less than 4% of the general population that may have cosmetic significance.

In what body regions are Minor Congenital Anomalies most common?

Areas of complex development — hands, feet, face, ears.

What does the presence of multiple minor anomalies indicate?

It may signal an underlying major congenital anomaly.

How common are Minor Congenital Anomalies in newborns?

15% of newborns

What are examples of Minor Congenital Anomalies?

flat philtrum, moderate fusion of toes 2-3 toes

What are Major Congenital Anomalies?

Structural or functional defects that have medical and social implications and usually require treatment and repair.

What percentage of early embryos have major congenital anomalies?

10–15% of early embryos — often leading to spontaneous abortion.

How does the detection rate of major congenital anomalies change with age?

Detection of major congenital anomalies increases with age. (Detection rate of 3% in neonates but 4-8% at 5 years)

What is the relationship between the number of minor anomalies per newborn and the chance of having one or more major anomalies?

Greater number of anomalies = greater chance of having major anomalies
- With 3 or more minor anomalies, there is a 90% likelihood of having multiple major anomalies
- Major anomalies associated with minor anomalies only become significant from 2 minor anomalies

What is primary abnormality?

Defect in the structure of an organ or a part of an organ that can be traced back to an anomaly in its development. It usually has a genetic or epigenetic cause.

What is secondary abnormality?

Interruption of the normal development of an organ that can be traced back to outer influences: teratogenic agents (infections, chemical substances, ionizing radiations) or a trauma (amniotic bands, vascular defect)

What is morphological defect?

Morphological defect is alteration to its normal configuration that can be present as complete or partial absence

What is the etiology and mechanism of malformation?

Etiology varies and mechanisms are unknown. Possible contributing factors are anomalies in cell differentiation, migration, proliferation, and death

When do defects of malformation arise?

Defect arises during organ formation

What does the intrinsically abnormal developmental process of malformations indicate?

Developmental potential of the organ is abnormal from the beginning = will always have anomaly

What are the Maternal Risk Factors that contribute to deformation?

• First pregnancy
• Small maternal size
• Small uterus
• Uterine malformation
• Uterine fibromata
• Small maternal pelvis

What are the Fetal Risk Factors that contribute to deformation?

• Oligohydramnios - lack of omniotic fluid
• Large fetus
• Multiple fetuses

What is the etiology of a disruption?

Etiology is varied
1. Teratogenic drugs
2. Ionising radiation
3. Hyperthermia
4. Infections
5. Vascular disruption
6. Amniotic band rupture

What is the relationship between genetic inheritance and a disruption?

A disruption cannot be inherited, but inherited factors can predispose to and influence the development of a disruption.

What is the usual etiology of dysplasia?

Genetic cause

The question on the page originate from the summary of the following study material:

Embryology

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