Lesions

Definition

Lesions are areas of abnormal tissue on the skin or eyes, often caused by infection, trauma, or disease. They can vary in appearance and may include ulcers, sores, or rashes.

5 Must Know Facts For Your Next Test

1. Lesions can be caused by bacterial, viral, fungal, or parasitic infections.
2. Common bacterial pathogens causing skin lesions include Staphylococcus aureus and Streptococcus pyogenes.
3. Viral infections like herpes simplex virus (HSV) and varicella-zoster virus (VZV) also lead to characteristic lesions.
4. Fungal infections such as those caused by dermatophytes result in ring-shaped lesions known as tinea or ringworm.
5. The appearance and location of a lesion can provide critical clues for diagnosing the underlying cause.

Review Questions

• What are some common infectious agents that cause skin lesions?
• How can the appearance of a lesion help in diagnosing its cause?
• Name two viral infections that typically result in skin lesions.

Related terms

Macule: A flat, distinct area of discoloration on the skin that is not raised above the surface.

Papule: A small, raised bump on the skin that is usually less than one centimeter in diameter.

Ulcer: An open sore on an external or internal surface of the body caused by a break in the skin or mucous membrane.