Introduction to Learning objectives • To Understand the basic structure of the skin Dermatology • To acquire the basic knowledge of the skin functions • Be able to describe skin lesions and presentations properly • Be familiar with the standard diagnostic tools in dermatology Dr. Sami N. Alsuwaidan ASSCOCIATE PROFESSOR AND CONSULTANT IN DERMATOLOGY AND LASER SURGERY DEPARTMENT OF DERMATOLOGY KING SAUD UNIVERSITY RIYADH, SAUDIA ARABIA 2 Important functions of the Dermatology skin Skin, hair, nails, and mucous - Protection against external injury membranes (mouth and genitila). - Fluid balance - Temperature buffering - Synthesis of Vit. D - Immune system - Cosmetic function 3 4 Cornified layer Epidermis Granular layer Why Dermatology ? Spinous layer Dermis Basal layer 5 6 1 1 Skin Anatomy 1 Epidermis 2 Basement membrane (dermoepidermal junction) Epidermis 3 Dermis 4 Subcutaneous fat Epidermis: Four layers (from outside – inside) 1. Cornified layer 2. Granular layer Dermis 3. Spinous layer 4. Basal layer Dermis contains: 1. Collagen fibers 2. Elastic fibers 3. Ground substances 4. Blood vessels 5. Nerves. Subcutaneous 7 8 Skin Appendages Hair follicle Sebaceous gland Arrector Pilli muscle Arrector pili muscle Eccrine sweat gland Hair follicle Apocrine sweat glands 9 10 Nail Anatomy Sebaceous gland Eccrine gland Apocrine gland 11 12 1 2 Examination Primary Lesions 1. Morphology 2. Configuration Secondary lesions 3. Distribution 13 14 Primary Lesions Macule Papule Plaque Nodule Wheal Vesicle Bulla Pustule 15 16 a 17 a 1 3 19 20 a a 21 22 23 24 1 4 Secondary lesions Crust Scale Ulceration Excoriation Scar Fissure Lichenification 25 26 28 a 30 a 1 5 31 32 34 35 1 6 38 Color and Shape Distribution Configuration 39 40 41 42 1 7 43 44 45 46 Dermatographism : When you stroke the Some specific signs in normal skin edema and erythema (you can write on skin!) .Seen in physical urticaria Dermatology Kobener Phenomenon : Induction of new skin lesions on previously normal appearing skin by truma e.g. in psoriasis, wart, lichen planus 47 48 1 8 Dermatographism Kobener Phenomenon 49 50 Additional skin examination: ~Wood’s Lamp : Produces long wave ultraviolet light(UVA). e.g. Vitiligo milky white Tinea Versicolor golden INVESTIGATIVE TOOLS Tinea Capitis (caused by microsporum) yellow green Erytherasma coral red ~Dermatoscopy : Helpful to differentiate benign from malignant pigmented lesions. 51 52 Investigations: *KOH and fungal culture •Scrap skin scales put over glass slide •Add KOH 10% -- warm gently •See under microscope •You may see hyphae and/ or spores 53 54 1 9 Skin Prick Test 55 56 Patch Test Investigations: Skin biopsy local anasthesia, different types: •Punch •Shave •Excisional •Incisional 57 58 59 60 1 10 61 62 Treatment: Topical Treatments Topical Various formulations: •Ointment Systemic •Cream •Gel •Solution •Lotion 63 64 Phototherapy Topical steroids Ultraviolet light A or B with or without psoralen PUVA (Psoralen + UVA) 7 Categories: New modalities: according to strength Narrow band UVB UVA – 1 Excimer laser(308nm) 65 66 1 11 Dermatology subspecialties Pediatric dermatology Photomedicine Laser Hair Disorders and Transplantation Dermatologic surgery Allergy/Contact dermatitis Dermatopathology Immunodermatology Others 67 68 1 12.