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Male Pattern Hair Loss (androgenetic alopecia)

Male pattern hair loss is an inherited condition, caused by a genetically determined sensitivity to the effects of dihydrotestosterone, or DHT. DHT is believed to shorten the growth, or anagen, phase of the hair cycle, causing miniaturization of the follicles, and producing progressively finer hairs. An enzyme called 5-alpha reductase regulates the production of DHT.(see also Androgenetic Alopecia)

Melanoma

Melanoma is a serious skin cancer, which is curable if detected early. Melanoma grows from pigment cells (melanocytes) in the outer layer of the skin and mucous membranes (epidermis). Although melanoma usually starts as a skin lesion, occasionally it occurs in other parts of the body such as the eye, mouth or vagina. Melanoma tends to spread out within the epidermis before moving into the deeper layer of the skin (the dermis). It can occur in adults of any age. Melanoma is common in people aged 50-70. Occasionally it can occur in teenagers but it is almost unheard of in children.

Miliaria

Miliaria is an itchy rash, which arises from obstruction of the sweat ducts. Miliaria is commonest in hot, humid conditions but may occur in desert regions. It affects up to 30% of people exposed to these climatic conditions. It may begin within a few days of arrival in a tropical climate but is maximal after 2-5 months. There is a striking variation in individual susceptibility. Infants are especially prone. Miliaria is another name for sweat rash or prickly heat. The typical spots develop in skin folds and on the body, especially in areas of friction from clothing. The lesions are minute red papules, which may be present in very large numbers. There is characteristically intense discomfort; not so much itching as an unbearable pricking sensation. In infants lesions commonly appear on the neck, groins and axillae, but also on the face and elsewhere. Once triggered off, an attack of miliaria commonly lasts 5-6 weeks despite the best treatment that can be offered. This is because the plugs which form in the sweat duct openings can only be cast off by the outward growth of the sweat duct cells. This takes several weeks. Treatment cannot influence this process.

Moles (nevi)

Moles are common harmless skin lesions. Moles (correctly called melanocytic or pigmented naevi) may be flat or protruding. They vary in color from pink flesh tones to dark brown or black. The number of moles a person has depends on genetic factors and on sun exposure. Moles begin to grow in infancy but new ones can appear at any age, sometimes in crops. Moles may darken following sun exposure or during pregnancy. During adulthood they often lose their pigmentation, and may disappear altogether in old age.

Molluscum Contagiosum

Molluscum contagiosum is a viral skin infection resulting in small, harmless skin growths. Molluscum contagiosum resemble pimples at first. Later, when the spots enlarge, they often have a waxy, pinkish look with a small central pit. Sometimes there are as many as a hundred spots on one individual. Molluscum contagiosum can be spread from person to person (especially children) by direct skin contact. It is harmless and never turns cancerous. It rarely leaves chicken pox- like scars. Usually the lesions disappear within 9-12 months, rarely lasting longer than two years. They do, however, tend to be more numerous and last longer in children who also have atopic eczema.

Morphea (localized scleroderma)

Morphea is a localized scarring of the skin characterized early by a violet colored rash and later by an ivory colored depression wich is hard. There is an associated loss of hair follicles and sweat glands. In Europe such leasions have been associated with a lyme disease-like infection. There is no effective treatment.

Mucous Cyst

A mucous or myxoid cyst arises from degeneration in the connective tissue on the top of the last segment of the finger. It may connect with the joint at the end of the finger. The cyst has a smooth shiny surface and is to be found at the base of the nail. It often causes a groove in the nail, a few millimeters across which extends the length of the nail. The cyst's size may vary. Jelly-like sticky fluid may be expressed from it (sometimes tinged with blood).