Types of Skin Conditions: Rashes, Lesions and Cancer

The different skin conditions are far too numerous to list: entire medical texts have been written on the subject. However, skin conditions tend to fall into six broad categories. Understanding the nature of these categories helps us understand the general nature of specific conditions.

Inflammatory Skin Disorders

Inflammatory skin disorders include a range of rashes and lesions that cause irritation and inflame the skin. Many of the more well-known skin conditions, including acne, fall into this category. Acne is characterized by clogged hair follicles that, when infected by bacteria, become pus-filled lesions. Other types of inflammatory skin conditions include:

• Dermatitis/Eczema: Characterized by red skin rashes, swelling, itching, and blisters.
• Diaper rash: Starts as redness on the baby's bottom. Most cases are mild, but in severe cases painful blisters can form.
• Psoriasis: The inflammation looks like raised red plaques on the skin, covered with thick white scales. Psoriasis that develops after a strep infection looks like small pinkish skin lesions.
• Sebaceous cysts: A sebaceous cyst is a blocked gland or duct. While usually not painful, a sebaceous cyst can become tender if infected. A grayish, odorous material can be drained from the cyst.

Viral Skin Problems

Most viral skin infections are temporary, although some can lead to scarring if left untreated. Many of the skin rashes caused by childhood diseases are viral in nature.

• Chicken pox: Symptoms include red blisters that cause itching. Chicken pox rarely causes lasting scars in spite of the urge to scratch the blisters. The virus can recur in later life, causing a painful condition called shingles: water blisters that become filled with pus, scab over, and then heal.
• Herpes simplex virus (Type 1): Spread by touching, kissing and sharing cups, Type 1 herpes usually leads to cold sores: small, clear, water-filled blisters, usually on the lips.
• Herpes simplex virus (Type 2): Usually spread by sexual contact, the disease is characterized by skin rashes, itching and sores around the genital area.
• Measles: Symptoms of measles include fever, coughing and a spreading skin rash.
• Warts: Caused by low-level viral infections, warts are smooth skin lesions. They may be lighter or darker than the surrounding skin.

Bacterial Skin Problems

Bacterial skin problems are easier to treat than viral infections, because antibiotics usually provide an effective treatment. Examples include:

• Folliculitis (Barber's Itch): Damaged hair follicles become infected with bacteria, resulting in skin rashes and pimples around the infected follicles. The infection can spread.
• Impetigo: A bacterial infection common to children, it is highly contagious and spreads easily. It causes itchy red skin lesions that crust over.

Skin Cancer

Three separate forms of skin cancer are recognized:

• Basal cell cancer: The vast majority — eighty percent — of all skin cancers are basal cell cancers that affect the upper layer of skin. Symptoms include new skin growths that bleed or don't heal well. The skin lesions vary in color from white to brown, and may be flat or raised.
• Squamous cell carcinoma: Comprises sixteen percent of skin cancers, and attacks the mid-layers of the skin layer. Symptoms resemble those of basal cell cancer.
• Melanoma: The rarest of the skin cancers (four to five percent of all skin cancers), melanoma is also the most dangerous. It spreads rapidly, attacking the cells that produce pigment, or skin coloring. The color of melanoma skin lesions varies: they often have irregular borders, change shape and size, and sometimes bleed. Watch for changes to existing moles.

Fungal Infections

Microorganisms that live on the skin cause fungal infections. These microorganisms live off dead skin cells, and are usually not a problem, but under the right conditions they can reproduce rapidly, leading to fungal infection.

• Athlete's Foot: Athlete's foot appears as an itching, burning skin rash on the feet or hands. Blisters often form, and the skin is red and inflamed.
• Candida: Candida favors warm, moist areas, so often occurs under the armpits and in the genital area. The skin becomes inflamed and itches, and may develop red lesions or rashes.
• Ringworm: Ring-shaped lesions or rashes appear on the skin. The lesions are itchy, and usually occur on exposed areas of the body, such as the inner arm. Ringworm is a misnomer, however, as the condition is caused by a fungus, not a worm.

Other Skin Disorders

Other skin problems include moles and birthmarks. Neither are health problems in and of themselves (although moles should be watched for changes that may indicate skin cancer). Birthmarks vary in size, color and location. Prominent birthmarks, particularly on the face, can cause people psychological distress.

Resources

Dermatology Channel. (nd). Herpes simplex virus (HSV). Retrieved March 19, 2002, from www.dermatologychannel.net/viral_infection/hsv.shtml

National Library of Medicine. (updated 2001). Sebaceous cyst. Retrieved March 20, 2002, from www.nlm.nih.gov/medlineplus/ency/article/000842.htm.

National Skin Centre (Singapore). (nd). Information on common skin diseases. Retrieved March 19, 2002, from www.nsc.gov.sg/cgi-bin/WB_GroupGen.pl?id=33.