Written by epgonline.org - Last updated 29 May 2018
Even mild skin disease can cause significant distress for patients, due to associated visibility and stigma, and this is of particular relevance for conditions which affect the face and hands. In this broad topic we cover conditions ranging in severity from life-threatening and highly disfiguring such as harlequin ichthyosis, to conditions as benign as freckles.
The disease topic can be broken down into several broad categories:
Non-malignant sun exposure related diseases. These range in prevalence from very common to rare conditions. Actinic keratosis is highly prevalent, the risks increase with age and male gender, and vary significantly by population – with prevalence in males of 15% in the UK, 26.5% in the USA, and up to 55% in Australia. Rarer conditions such as actinic reticuloid and poikiloderma of Civatte share the same risk factors.
Nail disease may be a result of local trauma, infection and neglect, or may represent a manifestation of systemic disease. Local disease may cause onycholysis (separation of the nail from its bed) or nail dystrophy (poor nail formation, often resulting from trauma or infection), while early signs of systemic disease may be evident from nail inspection – yellow nail syndrome and Beau’s lines are two examples.
Hair loss or abnormal growth can be a particularly distressing condition for patients. There are several forms of alopecia; it may be drug induced, but is thought to be autoimmune where no provoking factors are identified. Hirsutism is the other end of the clinical spectrum, with the most extreme manifestation of polytrichia, or werewolf syndrome.
Acne –acne vulgaris is the most common of the acneiform eruptions, a group of conditions affecting the skin and characterised by pustules in various layers. These may be in response to bacterial growth, or, in the case of hidradenitis suppurativa, they may be sterile.
Hypertrophic scarring is often the result of a genetic predisposition, and may lead to the keloidal appearance of surgical or other scars.
Disorders of sweat glands may also manifest as skin disease, with miliaria the consequence of obstruction of the ducts – the deeper the obstruction, the more prominent the symptoms. Excessive sweating (hyperhidrosis), abnormally offensive odour (bromhidrosis) and coloured sweat (chromhidrosis) may all be reasons for presentation to healthcare services.
Failure of some skin components may produce skin deformities. Scleroderma is an autoimmune process resulting in attack on the connective tissue, and may be systemic. Anetoderma results from a loss of elastin, and may be a consequence of Varicella virus scarring. Conditions of a similar nature may result from skin tissues extending into the wrong layer, such as reactive perforating collagenosis or elastosis perforans serpnigosa.