Difference Between Macular and Papular Rash

Key Difference – Macular vs Papular Rash
 

Skin is the largest organ of our body, and it acts as a physical barrier to microbes and a guardian of the internal structures. At the same time, it acts as a mirror that reflects the condition of the body’s internal environment. Rashes are one of the most common dermatological manifestations of local or systemic illnesses. Depending on the nature of the lesions seen, they are classified into two main groups as macular and papular rashes. Changes in the skin color or consistency without any elevation from the skin level are known as macules. A papule is a raised white lesion that is essentially less than 0.5cm in diameter. As their respective definitions indicate, the main difference between macular and papular rashes is that, in macular rashes, the lesions are not elevated from the skin level, while in papular rashes, the lesions have elevated edges from the skin level.      

CONTENTS

1. Overview and Key Difference
2. What is Macular Rash
3. What is Papular Rash
4. Similarity Between Macular and Papular Rash
5. Side by Side Comparison – Macular vs Papular Rash in Tabular Form
6. Summary

What is a Macular Rash?

Changes in the skin color or consistency without any elevation from the skin level are known as macules. The color of the lesion depends on the melanin content of the macule. When there is a high amount of melanin, lesion gets a black color and when the amount of melanin is low macule appear in white color.

Macular rashes appear in the following disease conditions

• Drug reactions
• Inflammatory reactions taking place within the body such as allergies
• Infections by viruses such as EBV and bacteria such as hepatitis

These rashes can be associated with other clinical features depending on the disease condition that has given rise to the rash in the first place. Usually, the patient has fever, malaise, fatigue and other nonspecific symptoms. When taking the history of the patient, it is important to ask about the exposure to any possible allergens and attention should be paid to the drugs that the patient is on.

What is a Papular Rash?

A papule is a raised white lesion that is essentially less than 0.5cm in diameter. All lesions with a raised margin that are more than 0.5 cm in diameter are known as nodules. Papules can appear either due to the changes in the dermis or epidermis.

Causes of Papular Rashes

1. Contact dermatitis
2. Allergic conditions
3. Infections such as fungal skin infections
4. Drug reactions
5. Leishmaniasis
6. Different forms of vasculitis

Similar to macules, papules also are associated with numerous other specific and nonspecific symptoms depending on the underlying cause of the condition.

In most occasions, patients get a maculopapular rash where the two varieties of the lesion are interspersed with each other simultaneously.

What is the Similarity Between Macular and Papular Rash?

• Both are dermatological manifestations which occur in various local or systemic disease conditions.

What is the Difference Between Macular and Papular Rash?

Summary – Macular vs Papular Rash

Changes in the skin color or consistency without any elevation from the skin level are known as macules. A papule is a raised white lesion that is essentially less than 0.5cm in diameter. Therefore the main difference between macular and papular rash is that macular rashes have lesions that are not elevated from the skin level while papular rashes have lesions with elevated edges.

Reference:

1. Buxton, Paul K. ABC of dermatology. London: BMJ, 2007

Image Courtesy:

1.”Urticaria” By BruceBlaus – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “Dermatomyositis12” By Elizabeth M. Dugan, Adam M. Huber, Frederick W. Miller, Lisa G. Rider –  (CC BY-SA 3.0) via Commons Wikimedia