A group of skin conditions involving thickening or overgrowth of the outer skin layer (keratin)

What is Keratosis?

Keratosis refers to a group of skin disorders characterized by the excessive growth or buildup of keratin, a protein that protects the skin. This results in rough, scaly, or hardened patches of skin. Keratosis is a broad term and includes several distinct types, some of which are harmless while others may carry a risk of progressing to skin cancer.

Keratosis can be benign (non-cancerous) or precancerous, and it is especially common in older adults or individuals with sun-damaged skin.

What causes Keratosis?

The causes depend on the type of keratosis, but common contributing factors include:

• Chronic sun exposure (especially for actinic keratosis)
• Aging
• Genetics (especially in inherited forms like keratosis pilaris)
• Skin damage or inflammation
• Viral infections (in some cases, such as in seborrheic keratosis)
• Impaired skin cell turnover

Who is at risk?

• Older adults, especially over age 40
• People with fair skin and history of sun exposure
• Individuals with a family history of keratosis
• Those with dry or sensitive skin
• People with weakened immune systems

What are the common types of Keratosis?

1. Actinic Keratosis (Solar Keratosis)

• Caused by sun damage
• Appears as rough, scaly patches on sun-exposed areas (face, scalp, arms)
• Considered a precancerous lesion that may develop into squamous cell carcinoma

2. Seborrheic Keratosis

• Common, benign skin growth
• Appears as brown, black, or tan wart-like lesions
• Typically found on the chest, back, or face
• Not caused by sun exposure and not cancerous

3. Keratosis Pilaris

• Caused by keratin buildup in hair follicles
• Appears as tiny, rough bumps, often on the upper arms, thighs, or cheeks
• Harmless but may be cosmetically bothersome

What are the symptoms of Keratosis?

Symptoms vary by type, but may include:

• Rough or scaly skin patches
• Raised, crusty, or warty growths
• Skin discoloration (red, tan, brown, or black)
• Itching or irritation
• In keratosis pilaris: small bumps that feel like sandpaper

How is Keratosis diagnosed?

Diagnosis is usually clinical and may include:

• Skin examination by a dermatologist
• Dermatoscopy to inspect the lesion closely
• Skin biopsy – if there is suspicion of cancer or if the lesion changes in shape or color

How is Keratosis treated?

For Actinic Keratosis:

• Cryotherapy (freezing the lesion with liquid nitrogen)
• Topical creams – 5-fluorouracil, imiquimod, diclofenac
• Photodynamic therapy
• Laser or chemical peels

For Seborrheic Keratosis:

• Usually no treatment needed
• Can be removed for cosmetic reasons via:
  • Cryotherapy
  • Curettage
  • Electrosurgery
  • Laser therapy

For Keratosis Pilaris:

• Moisturizers with urea, lactic acid, or salicylic acid
• Gentle exfoliation
• Topical retinoids in persistent cases
• Regular skin care and avoiding harsh soaps

What is the prognosis for Keratosis?

• Seborrheic and keratosis pilaris are benign and not dangerous
• Actinic keratosis can potentially develop into skin cancer if not treated
• Most forms are manageable with regular skin care or minor procedures

Can Keratosis be prevented?

Yes, especially for types caused by sun exposure:

• Avoid excessive sun exposure
• Use broad-spectrum sunscreen regularly
• Wear protective clothing outdoors
• Moisturize daily, especially for dry or sensitive skin
• Get regular skin checks to monitor for new or changing lesions