Category Archives: Dermatology


This type of infection may occur in moist wounds such as leg ulcers treated with occlusive bandages or dressings. Pseudomonas aeruginosa is the most frequent contaminant of such wounds. Astringent solutions such as acetic acid 1-2% will often dry the skin sufficiently to discourage the growth of Gram-negative organisms. Potassium permanganate 0.01% can be used as an alternative for bathing the limb or may be appl


Mast cells are normally distributed in the connective tissue of the skin and other organs. These cells release many substances, including histamines, from their granules. An increase in the number of mast cells is referred to as mastocytosis. It may be confined to the skin or, less frequently, may be widespread through all tissues including the viscera (systemic mastocytosis). Cutaneous mastocytosis Cutaneous


Erysipelas This is most commonly seen in the skin as widespread erythema and cellulitis. The organisms gain entry through fissures in the skin, e.g. in a toe-cleft, and the skin becomes red, swollen and tender. Constitutional symptoms of fever, malaise and hallucinations often accompany the cutaneous features. With recurrent disease the area affected, e.g. the foot and lower leg, may become lymph oedematous. TREATM

Bacterial infections

Infections Some of the bacterial, viral and fungal infections that affect the skin are considered in this section. Many skin infections are considered under the individual causative organisms. Bacterial infections An important role of the intact skin is to prevent the entry of infective organisms. This is achieved by the following: THE CORNIFIED SURFACE on many body sites is difficult to breach and has a desiccatin

Erythematous-scaly eruptions

DERMATITIS AND ECZEMA Dermatitis implies inflammation of the skin and can be due to many causes. It is usual to prefix the term with the causal agent, e.g. solar dermatitis. The characteristic features of dermatitis are: A RED AND HOT SKIN. Dermatitis affects the epidermis and superficial dermis. OEDEMA IN ACUTE STAGES. This separates the keratinocytes (spongiosis) and produces intradermal vesicles. WEEPING A


This pattern of eczema commonly affects the sides of the fingers, palms, the toes or soles of the feet. Irritant vesicles are the initial feature, though with more serious attacks bullae may be seen. The patients are usually in their twenties or thirties when they develop the disease. A previous history of atopy is not elicited in the majority of patients . Endogenous factors that trigger this type of eczema

Structure of the skin

The skin is divided into three layers: 1 The epidermis 2 The dermis 3 The subcutaneous layer The epidermis The epidermis consists of stratified epithelium. This is formed by cells (keratinocytes) from the germinal basal layer, which produces successive layers of cells that lose their nuclei and die as they reach the surface. The epidermis is divided into two layers: 1 The inner malpighian layer contains the germ

Functions of the skin

The skin acts as a protective covering to the body. Its functions are as follows: • It forms a physical barrier to antigens or bacteria. • It prevents excessive absorption or loss of water. • Its pigmentation prevents injury from ultraviolet (uv) light. • Vitamin D is synthesized by sunlight in the epidermis. • It is involved in temperature regulation. • Sensations of pain, touch and temperature can b


Introduction Skin diseases are extremely common but their exact prevalence is unknown. There are over 1000 different entities described but two-thirds of all cases are due to fewer than 10 conditions. These common conditions include acne, warts, eczema, infections due to bacteria, viruses and fungi, and psoriasis. Some conditions, e.g. acne, may be part of normal development while others may be inherited, e.g