MORPHOLOGY OF SKIN LESIONSDr. Riaz Uddin AhmedMBBS, DDV, MCPS,
FCPSAssociate Professor of DermatologyBangladesh Medical
A. Primary lesions- The original lesions are known as primary
lesion which are as follows:Macule, patchPapule, plaque, nodule,
B. Secondary Lesions: the primary lesions continue to full
development or may be modified by regression, trauma of other
extraneous factors, producing secondary lesion which are as
C. Special Lesion: lesions that are produced special
circumstances of body system which are as follows:Erythema-Erythema
A. Primary LesionsMucule- Latin: macula, spot Macules are
variously sized, circumscribed changes in skin color, without
elevation or depression and less than 1 cm in diameter
Patch: A patch is a circumscribed changes in skin color without
elevation or depression and 1 cm or greater in diameterPapule-
(Latin Paula, Pimple)Papules are circumscribed, solid elevations of
skin having diameter less than 1 cm
Plaques: (French- Plaque- Plate)A plaque is a broad papule (or
confluences of papules), 1 cm or more in diameter.
Nodules (Latins: nodulus- small knot)- Nodules are form of
papules but largest (>1 cm) and invade deeply.
Tumors are soft or firm and freely movable or fixed masses of
various sizes and shape. A tumor is an abnormal mass of tissue, the
growth of which exceeds and un-coordinated with normal tissue and
persists in the same excessive manner after cessation of stimulus
which evoked the change.
Wheals (Hives) wheals are evanescent, oedematous, flat
elevations of various sizes.
Vesicles (Latin Little bladder) vesicles are circumscribed
epidermal elevations 1-10 mm in size and usually containing clear
Bulloe (Latin-Bubble)- Bulloe are circumscribed or irregularly
shaped cavity more than 10 mm in diameter containing serous or
Pusteules (Latin- Pustula-Pus)- pustules are small elevations of
the skin containing pus
Secondary LesionsScales: (Latin Squama-scales)- scales are dry
or greasy laminated masses of keratin.
Excoriations (Latin Abrasio)- an excoriation is a punctate or
linear abrasion produced by mechanical means usually involving only
the epidermis and rarely reaching the papillary layer of the
Fissures (Latin- Cracks)- a fissure is a linear cleft through
the epidermis or rarely into the dermis caused by disease or
Erosions loss of all or portion of epidermis alone
Ulcers (Latin- Ulcus- Sore)- ulcers are rounded or irregularly
shaped excavations that result from loss of epidermis and
Crusts (Latin- crusta-bark)- crusts are dried serum, pus or
blood, usually mixed with epithalial and bacterial debris.
Scars ( )- scars are new formations in the dermis or deeper
parts as a result of injury or disease, as a part of the normal
reparative and healing process scar may be hypertrophic.
Keloid (Latin- Cheloid-clawlike)- a keloid is a firm,
irregularly shaped, thickened, hypertrophic, fibrous, pink or red
Hypertropic ScarKeloidClaw-like prejections absentThere is
claw-like projections present in Keloid Hypertrophic scar does not
extend beyond the original woundKeloid extend and spread beyond the
limits of the original injury In hypertrophic scar, there is
sponteneous improvement within first six monthsSponteneous
improvement does not occur in Keloid
Atrophy: this refers to a diminuation of some or all layers of
Cyst: a cyst is a cavity containing liquid or solid or
semi-solid material may be superficial or deep.Cyst
Erythema: erythema may be defined as redness of skin due to
dilatation of blood vassals which may be localised or wide spread
near the surface of the skin.
Erythema multiforme: erythema multiforme is a mucocuteneous in
which various types of skin reaction may occur from the same
causative agents and conversely many causative agents may induce
same cutaneous and mucous membrane reactions.
Erythema nodosum: erythema nodosum is an inflammatory but
non-suppurative condition of the skin characterized by
erythematous, tender nodules, usually located over extensor aspects
of lower limbs.
Erythroderma: erythroderma isa terminal condition of any
inflammatory disorder which affects either universally or more than
90% body surface area characterised by erythema, oedema, scaling,
thickening and itching chilliness caused by idiopathic, drug or
secondary to some reactional process to an underlying systemic or
Telengiactasia: permanent dilatation of blood vassals is known
Purpura: purpura may be defined as bleeding in the skin and
mucous membrane from the capillary at the arterio-capillary
junction which does not blanch on pressure and has progressive
Petechiae- are superficial, pinhead sized (less than 3 mm),
round, haemorrhagic macules, bright red at first then brwonwish or
Ecchymoses: siguify a deeper and extensive inter stitial
haemorrhage, which forms a flat irregularly shaped,
Vibices (singuler-vibex) are linear purpuric lesions.
Haematoma: designates a pool-like collection of extravasated
blood in a dead space in tissue that, if of sufficient size,
produces swelling that fluctuates on palpation.