Dermatology Lecture Vocabulary

30 vocabulary flashcards covering major dermatological conditions, treatments, signs and adverse reactions discussed in the lecture.

What is Atopy?

Atopy refers to an inherited genetic predisposition to develop allergic diseases such as asthma, hay fever (allergic rhinitis), and atopic eczema (dermatitis) due to an exaggerated immune response to common allergens.

Describe Atopic Eczema.

Atopic eczema, also known as atopic dermatitis, is a common chronic inflammatory skin condition, particularly prevalent in infants. It presents as dry, intensely itchy, and inflamed patches of skin, often found on the cheeks and in skin folds (flexures). This condition can be exacerbated by exposure to allergens, extreme temperatures, and hard water.

What is Pruritus?

Pruritus is the medical term for severe and often debilitating itching. It is a very common and distressing symptom associated with many skin conditions (dermatoses), including atopic eczema, and can significantly impact quality of life.

What is Lichenification and what causes it?

Lichenification is a dermatological term describing skin that has become thickened and leathery, resembling tree bark. This change is typically a result of prolonged, repetitive scratching or rubbing due to chronic itching, and it is frequently observed in conditions like flexural eczema.

What is an Emollient and how is it used in skin care?

An emollient is a moisturizing preparation, such as E45 cream, designed to hydrate and soothe the skin by forming a protective barrier that reduces water loss. Emollients are considered the first-line and cornerstone therapy for conditions like eczema, requiring liberal and regular application to maintain skin barrier function.

Why is Emulsifying Ointment recommended as a soap substitute, especially for eczema?

Emulsifying ointment is a specialized preparation used as a soap substitute for regular skin cleansing, especially beneficial for individuals with dry or sensitive skin conditions like eczema. Unlike conventional soaps which can strip natural oils and dry out the skin, emulsifying ointment helps to gently cleanse while simultaneously moisturizing, thereby preventing skin irritation and dryness.

When is Topical Hydrocortisone 1% used in treating eczema, especially for infants?

Topical hydrocortisone 1% is a mild corticosteroid cream used to reduce inflammation and itching in skin conditions like eczema. It is considered safe for short-term use in infants under 1 year of age when emollients alone are not sufficient to manage the symptoms, providing relief from acute flare-ups.

What is Telangiectasia and what can cause it?

Telangiectasia refers to the permanent dilation of small, superficial blood vessels, making them visible through the skin as fine red lines or patterns. On the face, this condition can sometimes develop as a side effect of prolonged or excessive use of potent topical steroids, which thin the skin and affect capillary integrity.

What is Impetigo and how is it related to eczema?

Impetigo is a highly contagious superficial bacterial skin infection, most commonly caused by Staphylococcus aureus. It frequently occurs as a secondary complication in individuals with eczema because the compromised skin barrier (due to dryness, scratching, or breakdown) makes eczematous skin more susceptible to bacterial invasion.

What is Contact Dermatitis and how is it managed?

Contact dermatitis is an inflammatory skin reaction that occurs when the skin comes into contact with an irritant substance (irritant contact dermatitis) or an allergen (allergic contact dermatitis). Common triggers include detergents, nickel, and cosmetics. Management primarily involves identifying and avoiding the causative agent, along with topical therapies to alleviate symptoms.

Describe Psoriasis and its characteristic symptoms.

Psoriasis is a chronic, non-contagious autoimmune skin disease affecting approximately 2\% of the population. It is characterized by an accelerated rate of skin cell turnover, leading to the formation of erythematous (red), inflamed patches of skin, often covered by distinctive silvery scales, known as plaques.

What is Plaque Psoriasis?

Plaque psoriasis is the most common form of psoriasis. It is characterized by clearly defined (well-demarcated) red patches on the skin, which are typically raised and covered with thick, silvery-white scales. These plaques commonly appear on the elbows, knees, lower back, and scalp.

What is Ringworm (Tinea Corporis)?

Ringworm, medically known as tinea corporis, is a common fungal infection of the skin caused by dermatophytes. It typically presents as distinct, circular or discoid and scaly lesions with raised, red borders and clearer centers, resembling a ring, which can appear anywhere on the body.

What is Candidiasis (Intertrigo)?

Candidiasis, particularly intertrigo, is a common yeast infection caused by Candida species. It primarily affects skin folds (e.g., under breasts, groin, armpits) where moisture and warmth create a favorable environment, leading to moist, red, inflamed skin (erythema) and significant soreness.

What is Tinea Pedis (Athlete's Foot)?

Tinea pedis, commonly known as athlete's foot, is a fungal infection of the feet caused by dermatophytes. It frequently develops in the spaces between the toes, characterized by itching, scaling, redness, and sometimes blisters, due to the warm, moist environment typically found in footwear.

How is Imidazole cream (Clotrimazole 1%) used effectively for fungal infections?

Imidazole cream, such as Clotrimazole 1%, is a broad-spectrum topical antifungal medication used to treat a variety of fungal skin infections. It is typically applied twice (b.i.d.) or three times (t.d.s.) daily to the affected area. For optimal effectiveness and to prevent recurrence, treatment should be continued for at least two weeks after the visible signs of the infection have cleared.

What are the key characteristics of Terbinafine (topical) as an antifungal?

Topical Terbinafine is an allylamine antifungal medication known for its potent fungicidal action. A key characteristic is its ability to penetrate deeply into the stratum corneum (outermost skin layer) and nail bed, where it accumulates, providing a prolonged antifungal effect even after treatment cessation, making it highly effective for dermatophyte infections.

What is Acne Vulgaris and its characteristic lesions?

Acne vulgaris is a common chronic inflammatory skin condition affecting the pilosebaceous units (hair follicles and their associated sebaceous glands). It is characterized by excessive sebum production, leading to clogged pores that manifest as comedones (blackheads and whiteheads), and can progress to inflamed lesions like papules, pustules, nodules, and cysts.

What is Basal Cell Carcinoma (Rodent Ulcer) and its prognosis?

Basal cell carcinoma (BCC), also known as rodent ulcer, is the most common type of skin cancer. It is a slow-growing malignant tumor originating from the basal cells of the epidermis, typically appearing as a pearly, translucent nodule with rolled borders. Despite being malignant, it rarely metastasizes and boasts an excellent prognosis with a greater than 97\% cure rate following surgical excision.

What is Malignant Melanoma?

Malignant melanoma is the most aggressive and potentially life-threatening form of skin cancer. It originates from melanocytes, the pigment-producing cells, and often develops within existing moles or de novo on sun-exposed skin. Early detection and removal are crucial for prognosis due to its high metastatic potential.

Explain the ABCDE criteria for assessing suspicious moles or lesions for Malignant Melanoma.

The ABCDEs of melanoma are a mnemonic used to help identify warning signs of malignant melanoma: Asymmetry (one half does not match the other), Border irregularity (edges are ragged, notched, or blurred), Colour variation (uneven distribution of color), Diameter greater than 0.5 cm (or 6 mm), and Evolving/Elevation (changes in size, shape, color, or a raised appearance). Any of these signs warrant medical evaluation.

What is a Spider Naevus and what can it indicate?

A spider naevus (or spider angioma) is a type of telangiectasia characterized by a central red spot (arteriole) from which tiny blood vessels radiate outward like spider legs. While they can occur normally, the presence of multiple spider naevi, especially on the upper body, is a classic cutaneous sign often associated with underlying liver disease, particularly chronic liver failure leading to elevated estrogen levels.

What is Jaundice and what causes it?

Jaundice is the yellow discoloration of the skin, mucous membranes, and the whites of the eyes (sclerae). It is caused by an accumulation of bilirubin, a yellowish pigment produced during the breakdown of red blood cells, in the blood. Jaundice is not a disease itself but a sign of an underlying systemic disease affecting the liver, gallbladder, or red blood cell breakdown.

What is the 'Glass-Test Rash' and what serious condition does it indicate?

The 'glass-test rash' refers to a non-blanching purpuric or petechial rash that does not fade or disappear when a glass is pressed firmly against it. This rash is a critical warning sign, especially in the context of fever or illness, as it can indicate meningococcal sepsis, a severe and rapidly progressing bacterial infection requiring urgent medical attention.

What is Urticaria and what are its characteristics?

Urticaria, commonly known as hives, is a skin condition characterized by the sudden appearance of transient, itchy, red or skin-colored raised welts or wheals. These wheals result from localized edema (swelling) in the superficial dermis due to the release of histamine and other mediators. Urticaria is a common manifestation of an allergic reaction, including drug allergies, insect bites, or food sensitivities.

What is an Erythematous Drug Eruption?

An erythematous drug eruption, also known as a maculopapular drug rash, is a common adverse drug reaction characterized by a widespread reddening of the skin with flat (macular) and/or raised (papular) lesions. The rash often resembles viral exanthems like measles and typically appears symmetrically on the trunk and limbs, triggered by systemic medication.

What is Toxic Epidermal Necrolysis (TEN)?

Toxic Epidermal Necrolysis (TEN) is a rare, severe, and life-threatening adverse drug reaction affecting the skin and mucous membranes. It is characterized by widespread epidermal necrosis and detachment, resembling a severe burn, covering more than 30\% of the body surface area, and carries a high mortality rate due to extensive skin loss, fluid imbalance, and risk of infection.

What is Stevens–Johnson Syndrome?

Stevens–Johnson Syndrome (SJS) is a severe, acute, and potentially life-threatening mucocutaneous adverse drug reaction. It is characterized by fever, widespread target-like lesions on the skin, and painful blistering that affects the skin and at least two mucous membranes (e.g., mouth, eyes, genitals), leading to epidermal detachment typically involving less than 10\% of the body surface area.

What defines a Penicillin Allergy and why is it important to document?

A penicillin allergy is an adverse hypersensitivity reaction to penicillin antibiotics, which occurs upon re-exposure to the drug. Reactions can range in severity from mild skin rashes (e.g., urticaria, erythematous drug eruption) to severe, life-threatening systemic reactions like anaphylaxis. It is critically important to accurately document penicillin allergies in patient records to prevent re-exposure and potentially fatal reactions.

How is Chlorphenamine used in the management of eczema?

Chlorphenamine is a first-generation, sedative oral antihistamine commonly used in the management of eczema, particularly at night. Its primary role is to reduce intense itching (pruritus) associated with eczema, and its sedative properties help patients achieve better sleep, which can be significantly disrupted by nocturnal scratching.