Psoriasis is a fairly common, chronic skin disease that runs in families. The disease is characterized by red plaques covered by thick, white scales. The lesions are usually present bilaterally on the outer surface of the body including the scalp. Common locations are the elbows and knees. Psoriasis is one of the few skin diseases manifesting the Koebner phenomenon. This term is used when psoriatic lesions occur at a site of injury, often weeks after the area has healed. The lesions are slightly itchy. Mild forms of psoriasis often respond to topical medications, such as steroid containing creams. Systemic therapies used for more severe disease include methotrexate, phototherapy and biological drugs such as Enbrel ®
Eczema is a general name that can cover a variety of usually very itchy disease processes. The more common are contact dermatitis (for example, poison oak) and atopic dermatitis. The latter affects about 15% of children in some countries, including the US. Usually, this very itchy disease manifests itself before the age of 5 years. Atopic dermatitis is commonly associated with dry skin and an atopic diathesis consisting of asthma and hay fever. Elevation of serum IgE and eosinophilia are common. Atopic dermatitis runs in families. In the very young, the disease can manifest itself on the face and flexural regions.
Hair Loss or Alopecia can come in a variety of forms, including the physiologic process seen with aging. This type, also called male pattern baldness, is very common and has a genetic basis. This process can be treated topically with minoxidil or orally with finasteride. Another fairly frequent alopecia is the autoimmune form called alopecia areata. It can vary tremendously in severity from the mild, self limiting form that usually resolves
on its own, to the severe form which can involve all of the hair on the body. This severe form of alopecia areata usually is chronic and very resistant to any form of treatment.
Acne, a word probably taken from the Greek word acme or peak, is a disease of teenagers and young adults and affects 40-50 million people in the US alone. It is a disease of the pilosebaceous unit and runs in families. Various forms of acne exist, including the mild comedonal acne to fulminant systemic disease. In the skin in these areas, the sebaceous gland produces sebum and at the start of puberty this production increases dramatically. This can lead to the formation of microcomedones, the first step in the acne process. The comedonal type of acne, characterized by black heads, white heads, papules and pustules (or pimples), usually affects the face and can also manifest itself on the trunk and upper arms. A wide variety of treatments exist, ranging from the topical, e.g., benzoyl peroxide, antibiotics, retinoic acid, to the systemic, e.g. antibiotics, contraceptives, retinoids.
Rosacea is a fairly common skin disease that ususally appears in older adults. It appears that the process is related to vascular hyper-reactivity that leads to one of the prime features of disease: namely, flushing. A variety of rosacea exist, including the milder, vascular rosacea that exhibits many telangiectasias (or dilated, small blood vessels) to the more severe, inflammatory form that includes the nodular enlargement of the nose. The treatments for this disease include topical as well as systemic antibiotics and retinoids. In the more severe forms of the disease, lasers and surgery sometimes are used.
Onychomycosis, or fungal infection of the nails, is frequently found involving the toenails, expecially in men. Various types of fungi can infect the nails causing increased thickness, ridging and discoloration of the nail plate. The diagnosis is made either clinically or by performing a test of a nail scraping., called a KOH preparation or culture of material obtained from the nail. Thsi nail infection, while cosmetically unappealing, does not represent a serious hazard to an individual's general health. Various treatments exist, including topical and systemic antimycotic agents. Systemic agents include terbinafine and itraconazole.