BASIC SCIENCE OF DERMATO-VENEREOLOGY

Dr. Chairiyah Tanjung, SpKKDepartement of Dermato-venereologyUniversity of North SumateraRSUP H.Adam Malik Medan

BASIC SCIENCE OF DERMATO-VENEREOLOGYSkin:The outermost layer, most complex structureA reflection of healthy man15% of body weight; area of 1,5-1,75 m2Thickness: 0,5mm-6mm

Basic science

Structure of the skinFunction of the skinStructure of genitaliaMicrobiology of the skinHistopathology of the skinMorphology and how to make diagnosisBasic science of dermatoimmunology

Structure of the SkinEpidermis1.1. Basal layer1.2. Malphigian layer (spinous layer)1.3. Granular layer1.4. Lucidal layer1.5. Stratum corneumDermis2.1. Papillary dermis2.2. Reticular dermis3. Sub cutis

Diagramatic cross section of the skin and panniculus

EpidermisBasal layerColumnar shape cell, pallisadeMitotically active, differentiate, the cells change in form while move upwardMelanocyte cell (+) melanosome melanin

keratinocyte dermis

Malphigian layer (spinous layer)The thickest layer: 6-8 layers; poligonal shapeGlycogen >> ; intercelular bridge (+)Langerhans cell (+)

Granular layer2-3 flatten cell layersCytoplasm: keratohyalin granules, basophilic, nucleus (+)Function:ApoptosisImpermeable water barrierLucidal layerFlatten cells, nucleus (-)Cytoplasm: protein eleidinClearly seen in hands and soles

Stratum corneum20-25 flatten cell layers, cornified, nucleus(-)Cytoplasm: keratinousDesquamation (+)

Merkel cellsFound between basal keratinocyte, in hairy/glaborous skinIntracytoplasmic neurosecretory like granules (+)

The dermisThicker than epidermisComposition: collagen fibers, elastic fibers, fibrous protein, cellular elements, hair follicles, vascular tissuePapillary dermis:Close to epidermisCollagen fiber & elastic fiber in small bundlesVascular and nerve ending (+)Reticulary dermisClose to sub cutisCollagen fiber & elastic fiber in big bundlesFunction: elasticity of the skin age elasticity

SUB CUTISLobule of fat cells separated by fibrous septaVary in thickness.Function heat insulator, mechanical barier, energy reserve.

The cutaneus vascularization : 1. Sub papillary plexus. 2. Deeper plexus.Associate with the vascular plexus are the dermal lymphatics.

EPIDERMAL APPENDAGES (THE ADNEXA).

1. Sweat glands: Eccrine glands. Apocrine glands. 2. Sebaceous glands. 3. Hair. 4. Nails.

Eccrine glandsApocrine glandsSize, formSmall, spiralBiggerLocationAll over the body, palms, soles, axilla, foreheadAxilla, areola, anogenital region, lids (gland of Moll), ceruminous glandsSecretWateryJuicyOrificeSkin surfaceInfundibular hair follicleInfluencing factorsCholinergic innervations, fear, emotionalAdrenergic innervation, catecholaminesFunctionthermoregulationUnknown; probably body odor

SEBACEOUS GLANDS.

Throughout all skin sites except the palms and soles.Holocrine, release products into the upper portion of the hair canal.Sebum: triglyceride, free fatty acid, squalene, wax ester, cholesterol.Influence by androgen.Sebum production: baby , children, adolescence.

HAIR.

All over the skin, except the palms and soles, dorsal phalanges, distal phalanges, labium minus, lips.Hair types : Lanugo hair fetus, baby. Velus hair 1 cm.Androgen hormon axillary hair, pubic hair, beard.Hair composition :carbon 50,60%, hydrogen6,36%, nitrogen 17,14%, sulphur 5.0%, oksigen 20,80%.

THE HAIR CYCLE.

The rate of hair growth is dependent upon mitotic activity of bulb matrix. 1. Anagen (growth stage) 2-6 years : 0,3mm/day. 85%-90% human scalp hair follicle are in anagen. 2. Catagen (degenerative stage). 2 weeks. Matrix activity(-), club hair (+).

THE NAIL.

Consist of horny product.Grows 1mm / week; fingernails growth>toenails growth.Functions:Esthetics.Protecting the distal phalanges.Enhancing tactile discrimination.The capacity to pick up small objects.Used for scratching and grooming.

THE FUNCTION OF THE SKIN:

1.Protection. 2.Absorbtion. 3.Excretion. 4.Perception. 5.Thermoregulatory. 6.Pigmentation. 7.Photosynthesis of vit D. 8.Keratinization.Another function: - skin immunologic - socio-sexual

1. Skin as protection organ

1.1Physical protection: - stratum corneum. - keratinization. - elastic and collagen fibers - fat tissue.1.2 Chemical protection: - impermeability of stratum corneum - acidity of the skin.1.3 Photo protection: - melanocyte. - thickness of stratum corneum. - urocanic acid.1.4 Microorganism protection - acidity of the skin - desquamation

2. Absorbtion function

skin permeability skin respiration

Influenced by many factors absorbtion (+)

intercellular gland orifice

epidermal cell

3. Excretion functionSebaceous gland sebum oily of the skin protection excessive evaporationSkin gland metabolic residue : NaCl, urea, uric acid, ammoniaProduct of sebaceous gland+Product of sweat gland acidity of the skin

4. Perception function

Kind of perceptionSensory receptorLocationTouchMeissners corpuscleMerkel RanvierDermal papillaeEpidermisPressurePacinian corpuscleDeep dermis, sub cutaneous tissueHeatRuffinis endsDermis, sub cutaneousColdKrauseDermisPainFree nerve endingPapillary dermis, basal layer

5. Thermoregulatory FunctionBy eccrine gland skin circulation constriction of blood vessels

6. PigmentationSkin colour depends on:~ thickness of the skin~ carotens~ melanin~ oxyhemoglobin~ deoxygenated hemoglobin

TyrosinaseTyrosine Dopaquinone + +

2 S Cysteinyldopa Leucodopachromeor5 S Cysteinyldopa Dopachrome

Benzothiazine intermediate 5,6 dihydroxyndole 2 carboxylic acid or Pheomelanine 5,6 dihydroxyndole Quinone Eumelanin

7. Photosynthesis of vitamin Dsunlight (295-300 nm)7 dehydrocholesterol vitamin D

8. Keratinization14 21 daysSkin protection againts infection by physiologic mechanism

Structure of genitalia

Male genitalia

Female genitalia

Lymphatic system of male / female genitalia

Horizontal tract of superficial lymph nodes and deep lymph nodesPelvic lymph nodes and lymph nodes along abdominal aortic

Organ Lymph nodesPenis Superficial deep

Srotum Spongy uretra Membranous & prostatic urethra

Prostate and seminal vesicles

Testis, epididymal ductSuperficial medial inguinal nodesSuperficial medial inguinal nodesDeep medial inguinal nodesSuperficial medial inguinal nodesSuperficial medial inguinal nodesDeep inguinal nodesVesicle lateral nodes internal iliac nodesSacral, external iliac nodes, internal iliac nodes, anorectal nodesExternal iliac nodes

organLymph nodesLabium majus

Labium minus

Bartholin s gland Clitoris

Urethra

Ovary Fundus of uterus Body of uterusSuperficial medial inguinal nodes, external iliac nodesSuperficial medial inguinal nodes, deep inguinal nodes, external iliac nodesAnterior vesicle nodesSuperficial medial inguinal nodes, deep inguinal nodes, external iliac nodesSuperficial medial inguinal nodes, deep inguinal nodes, interiliac nodes, gliteal inferior nodesNodes along abdominal aorticNodes along abdominal aorticNodes along abdominal aortic, superficial inguinal

Microbiology of the skin

Keratinization fat, nitrogen, mineral etc microorganism consuming colonization(+) pathogenMicroorganism opportunistic pathogen non pathogenCarrier : pathogen microorganism (+), clinical sign (-)Virulensi : depends on microorganism strain

Pathogenesis of bacterial infection towards the skin depends on :

Characteristic of pathogenic :invasive potensialtoxigen properties of the organismPortal of entry : Vascular wall : hemorrhage, thrombosis, infarctionCellular reaction systemic spread distant lesion3.Defense mechanism/ hospes immunity

Defense mechanism/hospes immunity1. Natural: - skin structure: - desquamation - acid mantle theory - dessication - chemical protection: -unsaturated fatty acid - bacterial interference o.t. skin - normal bacterial o.t. skin 2. Immunoglobulin & delayed type hypersensitivity- IgM in the sweat (-)- IgA, IgG, IgD, in the serum

Normal cutaneus flora

Transient skin floraResident skin floraComes fromOut of skinSkinPathogenicityPathogen, non pathogenNon pathogenMultiplicating(-)(+)Eradication from the skineasyhard

Normal flora in the orifice of the body

microorganismExternal acoustic meatusNasal vestibuleurethravulvaumbilicalMicrococci(+)(+)(+)(+)Diphteroid (+)(+)(+)(+)Staphylococcus(+)Streptococcus(+)Mycobacterium smegmatis(+)Enterococci(+)Coliform(+)Staphylococcus aureus(+)StreptococcusPyogenus(+)

Histopathology of the skin

defenitive diagnosisHistophatology helpful in making diagnosis

biopsy fixation processing-punch-scalpelcoloring Histopathology examination

Histopathologic alteration : Epidermis : hyperkeratosis, hypergranulosis, akantosis, hyperplasia, hypoplasia, atrophy, spongiosis, baloon degeneration, etc.Dermis : papillomatosis, sclerosis, fibrosis, etc.Sub kutis : inflamation, degenerative process, tissue necrosis, vasculitis.

Kulit Normal

Hiperkeratosis

Parakeratosis

Hipergranulosis

Akantosis

Celah suprabasal

Eksositosis, SpongiosisEksositosisSpongiosis

Degenerasi balon

Pemanjangan rete ridge

Papilomatosis

Good Luck!

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