Glossary

 

Glossary

Acne
A disorder of the skin caused by inflammation of the skin glands and hair follicles; found chiefly in adolescents and marked by pimples especially on the face

Acne vulgaris
A chronic acne involving mainly the face, chest, and shoulders that is common in adolescent humans and is characterised by the intermittent formation of discrete papular or pustular lesions often resulting in considerable scarring

Acrodermatitis continua of Hallopeau
Nail disease partly resembling nail psoriasis

Acropustulosis keratotica
Nail disease partly resembling nail psoriasis

Actinic keratosis
A scaly lesion, pre-cancerous to squamous cell carcinoma, occurring on the sun-exposed skin of the face or hands, particularly among older fair-skinned individuals

Alopecia
Absence of hair from areas where it is normally present

Alopecia areata
Loss of hair with no scarring to the affected area

Alopecia celsi
An old term for alopecia areata still occasionally used

Androgenic
Associated with an androgen (male hormone) dependency

Anosmia
Loss of sense of smell

Antimycobacterials
Antibiotic drugs that are active against mycobacteria

Apthous ulcers
The commonest type of mouth ulcers

Atopic
Inherited tendency to develop allergic reactions

Autosomal 
A non-sex chromosome. It is an ordinarily paired type of chromosome that is the same in both sexes of a species

Besnier's prurigo
Atopic eczema

Café au lait macules
Coffee coloured spots or patches that become apparent in early life

Causation pathway
Known contributory causes

Chilblain
Redness, itching, and burning of the skin, especially the fingers, toes, heels, nose, and ears on exposure to extreme cold and high humidity. Skin lesions may become blistered and or ulcerated

Chondrodysplasia punctata
A hereditary disorder in infants and young children which causes stunted growth due to a skeletal abnormality

Closed comedone
'Whitehead' ie a blocked pore with its opening not visible

Collodion baby
A newborn baby with a tight, shiny skin that can be present due to various ichthyoses

Comedone
Blocked pore

Corticosteroids
Synthetic glucocorticoids (similar to hormones) used to treat atopic eczema among other diseases to suppress inflammation, allergy and immune responses

Cradle cap
A form of seborrheic dermatitis of the scalp in infants that is characterised by flaky or scaly skin which may be reddened. May involve the skin on the nose, eyebrows, scalp, ears, and skin of the trunk (in skin folds)

Cryotherapy
The use of cold as a surgical treatment, commonly with either carbon dioxide snow or liquid nitrogen

Cutaneous
Relating to the skin

Dandruff
Dried skin that flakes free from the scalp

Decoction
The liquid resulting from boiling a substance in water to extract the essence, e.g. herb tea

Dermatitis
Itchy skin condition characterised by ill-defined red patches

Dermatology
Medical speciality concerned with the diagnosis and treatment of skin diseases

Dermatomyositis
Weakness and inflammation of muscles associated with a purplish skin rash

Dermatophyte
A fungus that can infect dead skin and nails

Desquamation
Peeling/scaling of the skin

Distal portion of the nail
Mid area of the nail (as opposed to proximal which refers to the nail bed)

Dyschromia
Any abnormality in the pigmentation of the skin

Dyshidrotic
Abnormally wet or dry

Dysplasia
Abnormal tissue development

Dystrophic
Disordered growth

Ectodermic dysplasia
An inherited disorder characterised by defective hair and nails and a coarsening of the skin of the palms and the soles

Eczema
Itchy skin condition characterised by ill-defined red patches

Emollients
Skin moisturisers used in the management of many dry skin problems including atopic eczema

Epidermis
The outer layer of the skin

Epidermolysis bullosa
A group of inherited conditions where blistering occurs on minimal trauma

Epithelium
The cellular layer that forms the epidermis of the skin and lines the hollow organs and all passages of the respiratory, alimentary, and genitourinary systems

Erosion
Partial loss of the top layer of the skin (epidermis), resulting in a red, moist appearance

Erysipelas
An acute infection of the skin caused by the bacteria Streptococcus pyogenes, characterised by redness, pain, swelling, and fever

Erythema
Redness of the skin caused by increased blood flow; may be localised or generalised

Erythematous
Redness of the skin, usually due to dilation of the small blood vessels from inflammation

Expression (as of retinoid receptors)
Production of receptors on the cell wall

Exocytosis
Benign bony outgrowth, usually from the big toe

Ferritin
Iron-containing proteins that are widely distributed in animals, plants, and microorganisms. Their major function is to store iron in a nontoxic bioavailable form. Each ferritin molecule consists of ferric iron in a hollow protein shell (Apoferritins) made of 24 subunits of various sequences depending on the species and tissue types
 
Flexural involvement
Involving the creases of the skin; for example, backs of knees, crooks of arms

Focal hyperhidrosis
Excessive sweating confined to areas such as armpits or palms / soles

Follicular plugging
Blocked and enlarged openings to hair follicles

Folliculitis
Inflamation of hair follicles

Freckles
Light brown macules that darken in the sun

Fungus
Simple organism, fungi include yeasts and moulds

Generic dermatology quality of life scales
Practical questionnaires looking at the impact of skin disease and treatment on patients' lives

Granuloma annulare
A benign chronic rash of unknown cause characterized by one or more flat spreading ringlike spots with lighter centers especially on the feet, legs, hands, or fingers

Hanifin and Rajka diagnostic criteria
A long list of features, based on patient's history, family history and the appearance of the skin rash, used as a guide when diagnosing atopic eczema

Herpes zoster
Shingles

Humoral immunity
That kind of immunity which is conveyed through antibodies

Hyperhidrosis
Excessive sweating

Hyperkeratosis
Thickening of the skin

Hyperpigmentation
Excess pigmentation in a bodily part or tissue

Hypopigmentation
Low pigmentation

Hypertrophic
Thickened

Hypertrophic scar
An elevated scar resembling a keloid but which does not spread into surrounding tissues, is rarely painful, and regresses spontaneously

Ichthyosis
Inherited disorder of the outer, horny layer of the skin, causing the skin to become dry and scaly

Immunomodulators
Agents used to stimulate the immune system and work on eradicating the tumour

Induration
Thickening of the skin

Interdigital
Between the toes or fingers

Keloid
An excessive proliferation of connective tissue in response to a skin trauma and differs from a hypertrophic scar because it extends beyond the limit of the original injury

Keratin
A protein that is found in hair, nails and the outer layer of the skin

Keratinization
The process by which the skin produces the outermost horny layer

Keratinocytes
The cells that make up most of the epidermis (the outermost layer of the skin) and produce keratin

Koebner phenomenon
Lesions appearing on lines of trauma or other triggers

Lamellar
Retained keratin in large brown scales that lift at the periphery

Ludwig scale
The progression of female pattern baldness is generally classified on the Ludwig scale, which ranges from stages I to III

Lunula
Nail moon

Macule
A flat mark which may be inflamed (red) or pigmented eg a freckle

Melanoma
A potentially serious form of skin cancer caused by an overgrowth of the pigment cells commonly found in the skin

Melanocytes
The cells in the skin which give rise to skin colour

Metaplasia
Metaplasia is a condition where one type of cell transforms into another type of cell, because of a changed environment

Modalities 
Treatments

Mohs micrographic surgery
The removal of a tumour, layer by layer, until it has gone as determined histologically

Moles
A general term usually used to denote harmless collections of pigment cells in the skin. They may be present at birth, or they may develop in the first few decades of life

Morphological alteration
Affecting the form and structure of

Mycobacterium
A group of bacteria which cause a range of infections in humans including TB

Nail dystrophy
Destruction of the nail plate

Neurodermatitis
Atopic eczema, sometimes used to denote a form of eczema with a 'nervous' or habit induced component

Nodule
A deep skin lump

Nummular
Circular

Oedema
Swelling

Onycholysis
The loosening of the nails, beginning at the border

Onychomadesis
Loosening of the nail from the nail bed

Onychomycosis
A fungal infection of the nails

Onychorrhexis
Longitudinal ridging and splitting of the nails

Open comedone
Blackhead ie a blocked pore with its opening visible

Ophiasis
A form of alopecia areata in which the loss of hair occurs in bands along the scalp margin partially or completely encircling the head

Papule
A 'pimple' which sticks out from the skin, a raised spot

Parakeratosis
An abnormality of the horny layer of the skin resulting in a disturbance in the process of keratinisation/converting into keratin

Parakeratotic foci
Parts of the horny layer of the upper skin in which cells still contain nuclei

Parakeratosis pustulosa
Nail disease partly resembling nail psoriasis

Paronychia
Inflammation involving the folds of tissue surrounding the nail

Perinuclear vacuolization
A fluid-filled space within the cytoplasm of the cell surrounding the nucleus

Photodynamic therapy
The application of a cream to induce photo damage to a tumour using varying light sources

Pigmented
Coloured

Pilar keratosis
Rough bumps around hair follicles, most commonly on the back and outer side of the upper arms

Pilosebaceous
Relating to the hair follicles and sebaceous glands

Plantar
Relating to the sole of the foot

Plaque
A patch of abnormal skin, more than one cm in diameter, which feels different from the rest of the skin

Podiatry
The study and care of the foot

Polygenic
Inheritance of quantitative traits or polygenic inheritance refers to the inheritance of a phenotypic characteristic that varies in degree and can be attributed to the interactions between two or more genes and their environment. Though not necessarily genes themselves, quantitative trait loci (QTLs) are stretches of DNA that are closely linked to the genes that underlie the trait in question. QTLs can be molecularly identified (for example, with PCR or AFLP) to help map regions of the genome that contain genes involved in specifying a quantitative trait

Postherpetic neuralgia (PHN)
Pain occurring after herpes zoster

Prolactin
Prolactin (PRL) or Luteotropic hormone (LTH) is a peptide hormone primarily associated with lactation. In breastfeeding, the act of an infant suckling the nipple stimulates the production of prolactin, which fills the breast with milk via a process called lactogenesis, in preparation for the next feed. Oxytocin, another hormone, is also released, which triggers milk let-down

Pruritis
Itching

Psoriasis
A common skin condition characterised by persistent localised scaly pink patches on the elbows, knees, and scalp

Pustules
Pus-filled spots

Reductase
A reductase is an enzyme which lowers the activation energy for a reduction reaction

Refractory to treatment
Does not respond (well) to treatment 

Reticular
Lacy

Rosacea
Chronic inflammatory skin condition characterised by redness and spots on the nose, cheeks, chin, and forehead

Salmon patches
A dyschromia/discolouration of the nails resembling an oil patch

Scabies
Contagious itch or mange especially with exudative crusts (exuding pus) that is caused by parasitic mites and especially by a mite of the genus Sarcoptes (S. scabiei)

Skin cancer
A general term usually used to denote the three types of growths in the skin. The commonest type is basal cell carcinoma, or rodent ulcer, followed by squamous cell carcinoma and finally by the much rarer melanoma. Basal cell carcinoma doesn't spread and virtually never kills people. Squamous cell carcinoma can occasionally spread to lymph nodes and other organs. Melanoma if caught early is curable, but if it has spread deep down into the skin and blood stream, it can spread to other organs of the body like other cancers

Subungal hyperkeratosis
A horny (eg wart) growth beneath the nail

Telangiectasia
Dilated capillaries

Teratogenicity
Developmental abnormalities in the foetus

Tinea capitis
A fungal infection of the scalp, also known as 'ringworm'

Tinea pedis
Athlete's foot - a common fungal infection of the feet

Topical dermatological treatment
A treatment which is applied directly to the skin eg creams and ointments

Ulcer
Complete loss of the top layer of the skin (epidermis)

Urticaria
Hives

Vasculitis
Inflammation of small & medium-sized blood vessels - may be confined to the skin but may involve joints

Vehicle
A substance in which the active ingredient is dispersed. This determines the rate at which the active ingredient is absorbed through the skin

Vesicle
Very small blister containing clear fluid

Vitiligo
A condition whereby the skin loses its pigmentation in patches

Warts
Horny projection on the skin usually of the extremities produced by proliferation of the skin papillae and caused by any of numerous genotypes of the human papillomavirus. Specific types include flat wart, genital wart, plantar wart, and verruca vulgaris