This document provides a detailed overview and classification of various morphologic skin lesions. It describes raised lesions like papules, plaques, and nodules. Depressed lesions include erosions, ulcers, and atrophy. Flat and macular lesions include macules, patches, and erythema. Surface changes involve scales, crusts, excoriations, and fissures. Fluid-filled lesions are vesicles, bullae, and pustules. Vascular lesions include purpura and telangiectasias. The document also discusses the shape, arrangement, and distribution of skin lesions.

2. MORPHOLOGIC
SKIN LESIONS
DR TAHIR KAMAL
FCPS, D.Dsc (UK),
M.A.A.C.S (USA)

3. MORPHOLOGIC SKIN LESIONS
1. Raised
2. Depressed
3. Flat
4. Surface change
5. Fluid filled
6. Vascular

4. Morphologic lesions

5. RAISED LESIONS

6. PAPULE:
A papule is a solid , elevated lesion
less than 0.5 cm in size in which a signific-
ant portion projects above the plane of surrounding skin.

7. continue…
Papules surmounted with scales
are called Papulo-squamous
lesions.

8. continue…
Shapes & surfaces of papule:
Sessile, pedunculated, dome-shaped
Flat topped, rough , smooth , filiform,
mammilated, acuminate, umblicated .

9. PAPULE
Papules in lichen planus

10. PLAQUE
A solid plateau-like elevation that
occupies a relatively large surface
area in comparison with its height
above the normal skin level and
has a diameter larger than 0.5 cm

12. NODULE
A circumscribed, solid, round or
ellipsoidal palpable lesion larger
than 0.5 cm in size.

13. Types of nodule:
 Epidermal
 Epidermal-dermal
 Dermal
 Dermal-subdermal
 Subcutaneous
 Others ( tumor, gumma )

14. Surface of nodule may be:
 Smooth
 Keratotic
 Ulcerated
 fungating

15. Nodule

16. Nodular basal cell carcinoma

17. CYST:
A cyst is an encapsulated cavity
or sac lined with a true epithelium
that contains fluid or semisolid
material ,cell & cell products such
as keratin.

18. A cyst
Cystic hidradenoma

19. WHEAL
A wheal is the swelling of skin
that is characteristically
evanescent , disappearing within
hours.

20. A wheal

21. SCAR
A scar arises from proliferation of
fibrous tissue that replaces previously normal collagen after a
wound or ulceration breaches the reticular dermis.

22. Types of scars:
 Hypertrophic scar
 Keloid scar

23. SCAR

24. COMEDO
A comedo is a hair follicle infundibulum
that is plugged with keratin and lipids.
Types:
1-Open comedo
2-Closed comedo

25. COMEDO

26. DEPRESSED
LESIONS

27. EROSION
An erosion is a moist , circumscribed ,
Depressed lesion that results from loss
of a portion or all of the viable epidermal
Or mucosal epithelium.
e.g. TEN

28. EROSION

29. ULCER
An ulcer is a defect in which the epidermis
and at least the upper (papillary) dermis
Has been removed.

30. ULCER

31. ATROPHY
Atrophy refers to diminution in size of a
Cell, tissue , organ , or part of the body.
- Epidermal atrophy
- Atrophy of panniculus

32. ATROPHY

33. POIKILODERMA
It refers to combination of atrophy ,
telangiectasias and various pigmentary
changes over skin.

34. poikiloderma

35. SINUS
A sinus is a tract connecting deep
Suppurative cavities to each other
Or to the surface of skin.
Contents :
pus , fluid, keratin etc.

36. sinus

37. STRIAE
Striae are linear depression of the skin that
usually measure several cm in length and
result from changes to reticular collagen
that occur with rapid stretching of the skin.

38. striae

39. BURROW
A burrow is a wavy , thread like tunnel
through the outer portion of epidermis
excavated by a parasite.

40. BURROW

41. SCLEROSIS
It refers to a circumscribed or diffuse
hardening or induration in the skin
that is a result of dermal fibrosis.

42. SCLEROSIS

43. FLAT AND
MACULAR
LESIONS

44. MACULE
A macule is a flat lesion , even with the
surface level of surrounding skin, perceptible
as an area of colour different from the
surrounding skin or mucous membranes

45. A macule may be:
 Hyperpigmented
 Hypopigmented
 Depigmented

46. MACULE

47. PATCH
it is a flat area of the skin or mucous
membrane with a different colour from
its surroundings > 0.5 cm in size.

48. Patch

49. ERYTHEMA
Erythema is blanchable change in the
colour of the skin or mocous membranes
that is due to dilatation of arteries and
veins in the papillary and reticularis dermis.

51. ERYTHRODERMA
it is generalised deep redness of the
skin Involving more than 90% of the
body surface within days to weeks .
Scaling and desquamation generally
follows.

52. SURFACE
CHANGE

53. SCALE
It is a flat plate or flake arising from the
outer most layer of the stratum corneum.

54. Scale

55. Types of scale :
 Crack like
 Exfoliative
 Follicular
 Gritty
 Ichthyosiform
 Keratotic

56. continue…
 Pityriasiform
 Psoriasiform
 Seborrheic
 lamellar

58. CRUST
Crusts are the hardened deposits that
result when serum, blood, or purulent
exudate dries on the surface of the skin.

60. EXCORIATION :
Excoriations are surface exavations of
the epidermis that result from scratching
and are frequent findings in patients
experiencing pruritis .

62. FISSURE :
A fissure is the linear loss of continuity of
the skin surface or mucosa that results from excessive tension or
decreased elasticity of involved area.

63. LICHENIFICATION :
 Repeated rubbing of skin may induce a
reactive thickening of epidermis with
changes in underlying collagen.

64. Lichenification

65. KERATODERMA
It is excessive hyperkeratosis of the stratum
corneum that results in yellowish thickening
of the skin.

67. ESCHAR:
The presence of eschar implies tissue
necrosis, infarction , deep burns, gangrene
or other ulcerating process.

68. eschar

69. FLUID FILLED
LESIONS

70. VESICLE AND BULLA:
A vesicle is a fluid filled cavity or elevation less than 0.5 cm.
Whereas a bulla measures larger than 0.5 cm.

72. PUSTULE:
A circumscribed raised cavity in the epidermis or infundibulum
containing pus. The purulent exudate composed of leukocytes
with or without cellular debris , may contain bacteria or sterile.

74. FURUNCLE:
It is a deep necrotizing folliculitis with
Suppuration.

75. VACULAR
LESIONS

76. PURPURA :
Extravasation of red blood from cutaneous vessels into skin or
mucous membrane results in reddish purple lesion.

77. Petechie:
Small , pinpoint pupuric macules.
Ecchymoses:
Larger , bruise like pupuric patches.
Plapable purpura:
If a lesion is pupuric and palpable.

79. TELANGIECTASIA :
It is persistent dilatations of small
capillaries in the superficial dermis
that are visible as fine , bright, non_
pulsatile red lines or net like pattern
on skin.

81. SHAPE
ARRANGEMENT,
AND DISTRIBUTION
OF LESION

82. SHAPE OF SKIN LESION:
 Annular
 Round/nummular/discoid
 Polycyclic
 Arcuate
 Linear

83. Continue…
 Serpiginous
 Targetoid
 Whorled
 Reticular

85. Nummular

86. ARRANGEMENT
 Single
 Grouped/ herpetiform
 scattered

87. Arrangement of lesions
a) (b) Grouped pigmented areas in a speckled lentiginous naevus. (c) Grouped vesicles in herpes
simplex. (d) Grouped lesions within a mosaic plantar wart

88. Distribution of multiple
lesions :
 Dermatomal/zosteriform
 Blaschkold
 Lymphangitic
 Sun exposed
 Sun protected
 Truncal

89.  Intertiginous
 Localized
 Generalized
 Bilateral/ symmetrical
 Universal
 Extensor

90. Pointers &
Pitfalls in
Dermatologic
Diagnosis

91.  Approach each and every evaluation with patience and
thorough diagnosis.
 Beware of snap, curbside, or doorway diagnosis.

92.  Examine the entire mucocutaneous surface as well as
hair and nails.
 A new or changing mole should be carefully evaluated.

93.  Generalized pruritus of more than one month’s duration
mandates a complete systemic workup.
 Drug induced eruptions can mimic most skin conditions.

94. Beware of the atypical diagnosis. Atypical ‘’this’’ may be
‘’typical’’ that to someone
who has seen it before.

95. THANK
YOU!