Dermatology: Basic Discussion
Skin is the largest organ of the body ( 8% of total body mass)
SKIN is the heaviest organ of the body (16% of total body weight )
SKIN is the first step to your beauty !
Integumentary system : Skin & its appendages (hairs , nails ,sebaceous gland, sweat glands)
Layers of the skin :
A.EPIDERMIS
1.Stratum corneum (Horny layer)
2. Stratum lucidum (present in palm & sole only )
3. Stratum granulosum
4.Stratum spinolosum (Thickest layer)
5.Stratum basalis / germinativum
B.DERMIS:
1. Papilary layer
2. Reticular layer
Notes:
Thick skin means thick stratum corneum
Thickest epidermis in palm & sole.
Thickest dermis on the back .
Thinnest dermis is eyelids.
Major functions of SKIN :
Organ of protection ( Trauma , Sunlight etc.)
Secretion & excretion of substances (sweat , sebum ,drugs, etc)
Regulation of body temperature
Synthesis of Vitamin –D,
Percutaneous absorption of substance drugs)
Skin health depends on :
1. Genetic factors
2. Age
3. Environmental (occupational, sunlight)
4. Plenty of water intake
5. Anxiety free states – proper sleep – (physical & mental rest )
6. Low fatty diet & more vegetables intake
7. Avoid alcohol, tea , coffee
8. Appropiate skin care : Protection from sunlight, water wash , cosmetic use
Most common Skin problems in Bangladesh
Superficial fungal infection.
Bacterial infection
Viral infections
Scabies
Acne
Eczema/Chronic Dermatitis
Atopic Dermatitis
Urticaria
Insect bite hypersensitivity
Seborrhoeic Dermatitis
Psoriasis
Pigmentary disoders
Hairs & nail disorders
Nevus and skin tumours
Cutaneous symtoms : (Patients complaints )
Pruritus / Itching : may be defined as a sensation that produce desire to scratch.
Alteration of skin color : Hyper/hypo pigmentations , reddish , yellowish
Pain & burning
Dryness & scaling
Skin rashes
Blister
Disfiguration ( Skin ,nail , mucosa )
Hairs : decrease / increase
Cutaneous signs ( Doctors findings ) Basic skin lesions
Primary lesions
Macule (< .5 cm ) Alteration of color of skin without elevation or depression
Patch ( > .5 cm ) Alteration of color of skin without elevation or depression
Papules ( < ,5cm ) Solid epidermal elevation
Plaque (> .5cm ) Solid epidermal elevation
Nodules : Solid epidermal & dermal elevation
Blister : Fluid containing with in epidermis or sub epidermis
Vesicles ( < .5cm )
Bulla ( > . 5 cm)
# Secondary skin lesions:
Scales / Squama / Exfoliate / Pityriasis : dead keratinocytes
Crust : Dead keratinocytes + Serum + Inflammatory infiltrates
Fissure : Linear crake.
Erosion : Loss of Epidermis
Ulcer : Loss of epidermis and dermis or other part.
Pustule : Pus containing cavity.
Excessive formation of connective tissue—– Collagen fibers are arranged in parallel Scar—– Collagen fibers are arranged in claw-like — Keloid
◄ Special skin lesions
Erythema : Redness of skin due to cutaneous vasodilatation ( Temporary )
Telangiectasia : Permanent vasodilatation
Purpura : Extravasetion of blood ( Non- blanching )
Causes of generalized pruritus / itching?
Endocrine : Diabetes mellitus, Thyroid disorders-(Hyper & Hypo)
Hematological: Iron deficiency anemia, Polycythemia, leukemia, lymphoma, multiple myeloma
Enteric: Intestinal worm infestations
Hepatic: CLD, Viral Hepatitis
Renal cause: CRF
Psychological : Anxiety with depression
Physiological : Pregnancy
Dermatological ; SD, AD,scabies etc
Q common causes of generalized pigmentation?
1.Addison’s disease
2.Kala azar
3. Malaria
4.Chronic Liver disease
5.Internal Malignancy
6.Genetic
7.Ashy Dermatosis
8.Chronic Arsenicosis
9.Drugs; Amiodaron,Busulphen,Chloroquin, Chlorpromazin,Psoralen
Common bullous skin diseases?
1.Bullous Impetigo
2.Pemphigus vulgaris
3.Steven Johnson’s Syndrome ( Bullous drug reaction)
4.Dermatitis Herpetiformis
5.Bullous Pemphigoid
6.Insect bite Hypersensitivity
7.Herpes zoster
.Q.Common causes of oral ulcer?
1. Trauma
2.Aphthous ulcer
3.Oral Lichen Planus
4.Oral candidiasis
5.SLE
6.Pemphigus vulgaris
7.Secondary syphilis
8.Squamous Cell Carcinoma
9.SJS
10.Nutritional deficiency(Iron,Folic acid,zinc,Vit-B2)
Q.Emergency Skin diseases?
Drug reaction
Exfoliative Dermatitis
Psoriasis with arthritis
Pemphigus vulgaris
SLE
Herpes Zoster
Urticaria
Vasculitis
Cellulitis
Lepra reaction