Macule
• Definition: Circumscribedalteration in the colour of the skin of any size or shape
that is non-palpable and without depression and has no alteration in the skin
texture or scaling within the lesion
• Macule >1-2 cms in diameter is “large macule”
• Macule >2 cms in diameter is “area”
• Margins can be well defined or ill defined
• Shape can be circular, oval or irregular
• Color of macule – Erythematous, hypopigmented (e.g., nevus hypochromic),
hyperpigmented (e.g., melasma), depigmented (e.g., vitiligo)
Papule
• Definition: Small,solid, elevated, palpable lesion up to 0.5 cm in size formed
either by localized proliferation of tissue cells or infiltration with inflammatory
cells
• Papules sized 1-2 mms are called “micropapules”
• Shape: Sessile, pedunculated, dome-shaped, flat-topped, filiform, acuminate,
umbilicated
Nodule
• Definition: Solid,elevated, palpable lesion >0.5 to 1 cm in size formed either by
localized proliferation of tissue cells or infiltration with inflammatory cells. Unlike
papules, they extend deeper into the dermis or subcutaneous tissue. They often
appear as firm, rounded
• A nodule sized >1.0 cm is better be called a “large nodule”
• Shape: Ellipsoid or globular, pedunculated or sessile
• Surface: Smooth, keratotic, ulcerated or fungating
• Types: Depending anatomical component involved-
• Epidermal, epidermal-dermal, dermal, dermal-subdermal or subcutaneous
• Other features: Depending on underlying pathology-
• Warm, hard, soft, fluctuant, tender, movable or fixed
• Examples: Neurofibroma, leprosy, erythema nodosum
11.
Papules and nodulesof
varied morphology and size
in neurofibromatosis
Shiny, pearly umbilicated
papules in molluscum
contagiosum
12.
Plaque
• Definition: Solid,elevated, palpable lesion >1 cm in diameter with a flat plateau like
surface
• Formed by extension of coalescence of papules or nodules
• Plaque sized >2 cms are “large plaques”
• Shape: Round, oval, discoid (uniformly thickened) or annular with regular or irregular borders
• Types: Depending on anatomical component involved-
• Epidermal, epidermal-dermal, dermal, dermal-subdermal or subcutaneous
• Surface changes: Depending on underlying pathology-
• Scaling, necrosis, erosion, ulceration, crusting, eschcar formation
• Examples: Psoriasis, leprosy, granuloma annulare
13.
Plaque
Annular plaques inleprosy
Well-defined, erythematous,
scaly large plaques of
psoriasis vulgaris
14.
Vesicle & Bulla(Blister)
• Definitions:
• Vesicle: An elevated fluid-filled
lesion sized <0.5 cm
• Bulla: Fluid filled lesion sized >0.5
cm
• Formation: Vesicles or bullae arise from
the cleavage at either intraepidermal or
sub epidermal level by-
a. Formation of cavity
b. Collection of fluid
• Contents of vesicle: Clear, serous,
turbid, hemorrhagic
• Examples: Herpes
simplex, pemphigus,
scalds, bullous
pemphigoid
16.
Pustule
• Definition: Acircumscribed raised
pus-filled lesion
• Pustules may vary in size and in
certain conditions like pustular
psoriasis they may coalesce to
give “lake of pus” appearance
• Purulent exudate contain either
cellular debris, leukocytes, or
bacteria or may be sterile
• Pustules are superficial- heal
without scarring
• Examples: Bacterial (folliculitis),
pustular psoriasis Pustules in pustular psoriasis
17.
Cyst & Abscess
•Definition:
• It is localized accumulation
of pus deep in dermis or
sub cutis
• Usually not visible on the
surface of skin
• It is erythematous, warm,
tender, fluctuant nodule
• From staphylococcal,
streptococcal infections
• Abscess • Cyst
• Definition: A closed cavity or
sac (normal or abnormal)
that has an epithelial,
endothelial or
membranous lining and
contain fluid or semisolid
material
• Examples: Sebaceous cyst,
epidermal cyst (milia),
pilar cyst
Scale
• Scale
• Itis visible exfoliation of
flake of stratum corneum
• Morphology varies with type
of skin disease
Ichthyotic scales
20.
Name of Signor Scale Type Associated Diseases Clinical Description
Silvery, white scale Psoriasis vulgaris parakeratotic, lamellated scale.
Collarette scale
Pityriasis rosea, subsiding
furuncle, miliaria, erythema
nodosum
Fine scale attached at the
periphery and detached at the
center.
Greasy scale
Seborrheic dermatitis, Darier’s
disease
Loose, moist, oily scaling,
especially perifollicular.
Trailing scale
Erythema annularis
centrifugum
Scale located at the inner
border of an advancing
annular erythema.
Fish-like scale Ichthyosis vulgaris
Small, semi-adherent scale
with turned-up edges; may
have a "pasted-on
appearance".
Corrugated/Ridged scale
Bullous ichthyosiform
erythroderma (BIE)
Waxy scale buildup in skin
creases (neck, flexures, etc.) as
blistering fades.
21.
Name of Sign
orScale Type
Associated Diseases Clinical Description
Wafer-like
scale
Pityriasis lichenoides
chronica (PLC), clear cell
acanthoma
Thin mica-like scale; in PLC it is attached at the center
and free at the periphery.
Double-edged
scale
Ichthyosis linearis
circumflexa (ILC) /
Netherton syndrome
An incomplete advancing double edge of peeling
scale on an annular or polycyclic flat patch.
Cornflake
sign/scale
Flegel’s disease,
Pemphigus foliaceous
Keratotic scaly papules with discrete irregular
margins; also used for scale-crust in pemphigus.
Sandpaper-
like scale
Actinic keratosis Firmly adherent, dry, rough scales.
Plate-like
scale (Armor
plate)
Lamellar ichthyosis Large, thick, rigid scales arranged in a mosaic pattern.
22.
Name of Signor Scale Type Associated Diseases Clinical Description
Mauserung desquamation Ichthyosis bullosa of Siemens
Circumscribed patchy scaling
with focal desquamation or
"moulting".
Hystrix-like scale Ichthyosis hystrix
Porcupine spine-like scaling
over verrucous lesions.
Coat of armor Harlequin ichthyosis
Infant encased in a rigid, taut,
hyperkeratotic shell.
23.
Crust
• Crust
• Crustis dried up exudates (blood,
serum, pus)
• Removal of crusts leave moist
surface/erosion beneath
• Colour of crust varies with nature of
exudate:
• Yellow-brown– dried serous secretions
• Turbid yellow-green- purulent secretion
• Reddish black- hemorrhagic secretion
Hemorrhagic crusts
24.
Erosion
• Erosion
• Raw,moist lesion left from a complete or partial
loss of epidermis or mucosal epithelium
• Results from trauma, rupture of vesicles or bullae,
or epidermal necrosis
• Heal without scar unless secondarily infected
• Examples: in pemphigus, SJS-TEN
Erosions, hemorrhagic crusts
in a pemphigus patient
25.
Ulcer
• Ulcer formsfrom breach and destruction of skin
(epidermis, dermis with basal layer, adnexal
structures) or mucosa
• Heals with scarring
• May be superficial or deep
• Margins of ulcer:
• Overhanging- tubercular
• Punched out– gumma
• Light pink granulation tissue at floor- healing
Ulcer
26.
Fissure
• It isa linear, triangular crack in the
skin/mucosa
• Results from excessive tension or
decreased elasticity of the involved
tissue
• Can be superficial or deep
• Deep fissures are painful
• Common over palms and soles due
to thick stratum corneum
• Examples: In palmoplantar psoriasis,
keratodermas, irritant CD Fissures of heels
28.
Excoriations
• Linear orcircumscribed erosions formed from
surface excavations of epidermis due to
scratching
• Frequent finding in patients having disorders
with pruritus
Linear and punctate excoriations
on the back induced by
scratching
29.
Sinus
• It isa tract connecting a deep
cavity to the surface of the skin
• Contents of the deep cavity are
usually pus, epithelial debris
• These contents drain to the
surface when such a channel
exits
Multiple sinuses in nocardiosis
30.
Scar
• It isthe proliferation of fibrous tissue
that replaces the normal collagen after
the ulcer involving the reticular dermis
heals
• Epidermis is thinned and wrinkled, and
adnexa like hair are destroyed
• Hypertrophic scars: Typically take form
of plaques or nodules
• It does not grow beyond the limit of
original lesion
• Keloid: Exceeds the limit of original
lesion Keloid
31.
Lichenification
• Definition: Thickeningof skin due to
repeated and prolonged
rubbing/scratching of skin characterized
by:
• Thickening of epidermis/dermis
• Accentuated of skin markings
• Hyperpigmentation
• Examples: Lichen simplex chronicus
(LSC), lichenified chronic (atopic)
dermatitis
Lichenification (LSC)
32.
Atrophy
• Definition: Aloss of cutaneous mass
from diminution in size of any of
the components of skin
• Epidermal atrophy: Glossy, transparent,
cigarette-paper like thinning and
wrinkling, loss of normal skin lines
• Dermal atrophy: Circumscribed area of
depressed skin, normal in colour
and surface
• Subcutaneous atrophy: Substantial
depression of skin Epidermal atrophy
Erythema
• Localized ordiffuse
"redness of the skin"
blanched on pressure
• Due to vascular
congestion or increased
skin perfusion
• Rosacea, viral exanthem
and SLE
35.
Erythema/Purpura
• Erythema: Blanchesredness of skin, and is due
to vascular congestion or increased perfusion
e.g., facial erythema in rosacea
• Purpura: Non-blanching reddish to purple
discolouration of skin due to extravasation of
RBCs in dermis e.g., vasculitis, bleeding
disorders
• Petechiae: small pupuric lesions, Occur in crops
e.g., clotting disorders
• Ecchymosis: Larger purpuric lesions from
extravasation of blood
• Diascopy: Differentiates erythema from
purpura
37.
Wheal (Hives, Urticaria)& Angioedema
• Definition: An evanescent (lasting 48-72
hrs) erythematous, elevated lesion due to
oedema of dermis (wheal) frequently with
central pallor, or dermo-hypodermis with
loose dermal tissue e.g., lips, eyelids,
scrotum (angioedema)
38.
Burrow
• Definition: Itis wavy, thread like
tunnel excavated in the stratum
corneum by scabies mite
• It measures only few mms in
length
• Characteristic of scabies and
particularly seen over palms and
soles, wrists and genitalia in
infants and very young children
39.
Comedo (Pl. Comedones)
•Definition: A dilated
pilosebaceous orifice plugged
by keratin and sebum
• Open comedo: Pilosebaceous
opening is open to the surface
of skin by black keratinous plug
• Closed comedo: Closed
pilosebaceous opening is
unapparent, accumulates the
whitish keratin
• Characteristic and primary lesion of acne
40.
Milium
• Definition: Atiny white
superficial cyst with epidermal
lining containing lamellated
keratin
• Sometimes arise on blistered or
damaged skin e.g., after
dystrophic epidermolysis
bullosa, porphyria,
dermabrasion
41.
Telangiectasias
• Definition: Visibleand persistent
dilatations of small capillaries in the
superficial dermis that appear as fine,
bright non-pulsatile, net like pattern on the
skin
• May or may not disappear with diascopy
• Types: Mat-like, punctate, linear
• Examples: In-rosacea, collagen vascular
diseases
42.
Sclerosis
• Definition: Adiffuse induration
and hardening of skin due to
dermal fibrosis
• The skin feels firm board like,
immobile and difficult to pick up
• Examples: Morphea, systemic
sclerosis
Morphea
43.
Poikiloderma
• Definition: Adappled appearance of
skin from combination of atrophy,
telangiectasia and pigment changes
(hypo or hyperpigmentation)
• Example: Rothmund thomson
syndrome, xeroderma pigmentosa
Poikiloderma in
xeroderma pigmentosa
44.
Target Lesions
• Definition:These have 3 zones:
• Central: dusky, blistered or
purpuric zone
• Middle: pale zone of oedema
• Outer: Erythematous zone
with well defined edge
• Example: Erythema multiforme
45.
Further Description
• Shapeof lesions: The shape of each lesion – dome-shaped, flat
topped, umbilicated, acuminate, pedunculated, verrucous
• Distribution of lesions: The overall distribution of lesions – scattered,
disseminated, widespread, confluent, symmetrical or asymmetrical,
acral
• Pattern of lesions: The arrangement of individual lesions - annular,
arcuate, linear, grouped, discoid, reticulate, gyrate
• Colour of skin and of lesions: e.g., purplish (LP), yellowish (xanthoma),
etc.
