Difference Between Atrophy and Dystrophy

The key difference between atrophy and dystrophy is that atrophy is a disorder that causes partial or complete wasting away of a part of the body and decrease in size of a cell, organ or tissue, while dystrophy is a group of disorders that causes weakness in the tissues in the body and leads to reduced mobility.

The body has levels of organization that build on each other. In the human body, cells make up tissues, tissues make up organs, and organs make up organ systems. Basically, the function of an organ system depends on the integrated activity of its organs. Atrophy and dystrophy are two disorders related to the degeneration of tissues of the body.

CONTENTS

1. Overview and Key Difference
2. What is Atrophy 
3. What is Dystrophy
4. Similarities – Atrophy and Dystrophy
5. Atrophy vs Dystrophy in Tabular Form
6. Summary – Atrophy vs Dystrophy

What is Atrophy?

Atrophy is a disorder that causes partial or complete wasting away of a part of the body. It is also known as the reduction in the size of a cell, organ, or tissue after attaining its normal mature growth. The causes of atrophy include gene mutation, poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply to the target organ, an excessive amount of apoptosis in the cells, lack of exercises or diseases intrinsic to the tissue itself.

In the medical context, the hormonal and nerve inputs that maintain an organ or body part have tropic effects. A diminished trophic effect or condition is designated as atrophy. There are different types of atrophies, such as muscular atrophy, gland atrophy and virginal atrophy. Muscular atrophy is more common and occurs due to ageing or diseases like polio, severe malnutrition, Guillain Barre Syndrome, burns and neuropathic atrophy, etc. There are two types of muscular atrophy. One is due to post prolonged disuse of a group of muscles. The other is due to neurogenic atrophy occurring in post injuries to nerves associated with a set of muscles.

The best example of gland atrophy is adrenal glands atrophy, which occurs during prolonged use of exogenous glucocorticoids like prednisone. Moreover, virginal atrophy occurs in post-menopausal women, where the walls of the vagina become thinner.

What is Dystrophy?

Dystrophy is a group of disorders that causes weakness in the tissues of the body and leads to reduced mobility.  Dystrophy is also defined as the degeneration of tissue due to disease or malnutrition, which is most likely due to heredity. There are different types of dystrophies, such as muscular dystrophy, reflex neurovascular dystrophy, retinal dystrophy, cone dystrophy, corneal dystrophy, lipodystrophy, and nail dystrophy.

Muscular dystrophy is more common and can occur due to hereditary inheritance, which usually has a genetic mutation at the root of the family. Muscular dystrophies may follow X-linked recessive inheritance, autosomal recessive inheritance, or autosomal dominant inheritance. Some muscular dystrophy conditions are also due to sudden mutations following radiation. Muscular dystrophy causes progressive weakness and breakdown of skeletal muscles over time. Some examples of muscular dystrophies are Duchenne muscular dystrophy, Becker muscular dystrophy, facioscapulohumeral muscular dystrophy, and myotonic dystrophy.

What are the Similarities Between Atrophy and Dystrophy?

• Both disorders are related to the degeneration of tissues in the body.
• They are cause muscle diseases.
• Both have a genetic basis.
• They can also be due to poor nutrition.

What is the Difference Between Atrophy and Dystrophy?

Atrophy is a disorder that causes partial or complete wasting away of a part of the body and a decrease in the size of a cell, organ, or tissue. Dystrophy is a group of disorders that causes weakness in the tissues in the body and leads to reduced mobility. So, this is the key difference between atrophy and dystrophy.

The below infographic shows more differences between atrophy and dystrophy in tabular form.

Summary – Atrophy vs Dystrophy

The cells in complex multicellular organisms like people are organized into tissues. Organs are structures made up of two or more tissues that are organized to carry out a specific function. Group of organs with related function make up the different organ systems in the human body. Normally, the function of an organ system depends on the integrated activity of its organ. Atrophy and dystrophy are two disorders that related to the degeneration of tissues of the body. Atrophy is a disorder that causes partial or complete wasting away of a part of the body. On the other hand, a dystrophy is a group of disorders that causes weakness in the tissues in the body and leads to reduced mobility. Thus, this is the summary of the difference between atrophy and dystrophy.

Reference:

1. “Atrophy.” Encyclopædia Britannica, Encyclopædia Britannica, Inc.
2. “Muscular Dystrophy: Symptoms, Diagnosis, and Treatment.” WebMD.

Image Courtesy:

1. “1025 Atrophy” By OpenStax –  (CC BY 4.0) via Commons Wikimedia
2. “Myotonic dystrophy patient” By Herbert L. Fred, MD, Hendrik A. van Dijk – (CC BY 1.0) via Commons Wikimedia