dermatology revision notes for neet pg preparation based on lecture notes with high yield topic & last minute revision notes based on previous year questions

1. Pigmentation disorders of skin

2. Hypopigmented
• Symmetrical
• Vitiligo
• Piebaldism (AD)
• Albinism (AR)
• Asymmetrical
• Pityriasis alba / versicolor
• Ash leaf macule
• Nevus anemicus
• Nevus achromicus
• Nevus depigmentosis
Congenital

3. Pityriasis alba
• Hypopigmented recurrent scaly macule
• In children (6-12 yr) decreases on puberty
• On cheeks and face
• Recurrent and more common in summer

4. Piebaldism
• Congenital AD
• Localised depigmented macule
with symmetrical involvement of
central forehead, ventral
trunk,upper and lower extremities
with acral sparing
• White forelock
• Wardenberg syndrome =
piebaldism + SNHL

5. piebaldism
• Characteristically areas of hypopigmentation contain
hyperpigmented or normally pigmented macules or Islands of hyper
pigmentation within the lesions

6. Albinism (albin is recessive)
• Congenital AR
• Complete absence of melanin
• Albinism should not be considered as a differential diagnosis of
hypopigmented macule/patch as there no patch / macule, instead
there is diffuse hypopigmentation of skin & hair throughout the body.
• Associated eye defects
• Absence of pigment in iris and retina (eye defects are present in all cases)

7. Nevus achromicus
• u/l Single hypopigmented patch on trunk
or proximal extremity + erythema
response present on massage (unlike
naevus anemicus )
• Limited to single neuronal segment
• Feathered margins
• No leucotrichia (unlike vitiligo )
• Does not disappear on pressure with
glass slide
• Present at birth and static (do not
increase in size )

8. Nevus anaemicus
Presents since birth and static
• vascular anomaly presents clinically as
hypopigmented patch or macule.
• Pressure on lesion makes the lesion to disappear
and indistinct from surrounding skin.
• Most commonly on the upper chest.
• f. Massage fails to develop erythema (in
contrast to Nevus achromicus)

9. Nevus achromicus Nevus anemicus
Diascopy Can differentiate fromsurrounding
skin
Cannot differentiate from
surrounding skin
Heat Erythema develops No erythema

10. Becker nevus
• Irregular pigmentation of
shoulder , upper chest or
scapula region

11. Vitiligo
• depigmented or nonpigmented nonscaly macule sharply defined
• Acquired
• Associated with AutoImmune d/s
• DM, thyroid d/s (hypothyroidism) alopecia areata, addisons d/s
• koebner phenomenon +
• Can occur anywhere in body (depending on type of vitiligo ~ areas subjected
to repeated friction & trauma are frequently affected, i.e. Dorsum of hands &
feet, knee, elbow)
• Lecotrichia (depigmented hair) poor prognosis
• Lesion on face best prognosis

12. Vitiligo
• Most cases begin between the age of 10-30 years
• Margins are elevated and hyperpigmented àSalloped hyperpigmented
margins
• Vitiligo
• Vitiligo vulgaris
• Segmental  stable & static course /not associated with AI d/s
• Vitiligo universalis
• Generalised vitiligo
• Lip tip ,tip of penis,vulva and nipples involved

13. Segmental • u/l along dermatome
• Stable & static course
• Not associated with AI disease
Vitiligo vulgaris • Most common
• b/l symmetrical
Acrofacial
Lip tip • Involvement tip of lip nipple penis finger tips
Vitiligo universalis • Generalised
• a/w AI d/s like DM pernicious anemia hashimotos
ds

14. • Trichrome vitiligowith three colors (white, light brown, dark brown)
represents different stages of evolution

15. • Poor prognosis
• Leucotrichia
• Lesion over bony prominences
• Acrofacial type
• Long standing

16. Treatment
• <20 %
• Topical steroids
• Topical vitamin D analogue
• β FGF cream
• Topical immunomodulators  tacrolimus
• If no response
• PUVA/ PhotoRx
• If no response
• Grafting/ melanocyte transplant
• >20%
• Systemic steroids
• Azathioprine
• Levamisole
• Phototherapy
• Narrow band UVB  radiation of choice
• PUVA
• PUVASOL( PUVA +SOLarlight)

17. Sx treatment of vitiligo
• Ultra thin partial thickness skin graft
• Autologous melanocytic transfer
• Cultured
• Noncultured

18. Hyperpigmented lesions

19. Ceruloderma
• Blue coloured skin
• 3 types
• Nevus of ota
• Nevus of ito
• Mongolian spot

20. Nevus of ito
• Pigmentation of skin innervated
by lateral branches of
supraclavicular nerve
Nevus of oto
• Oculodermal melanosis

21. Nevus of ota Nevus of ito
both • u/l
• Bluish grey
• u/l
• Bluish grey
Site Trigeminal nerve (ophthalmic &
maxillary division )face
Acromiocalvicular nerveshoulder
& posterior neck
Malignant potential Rare present with i/Lglaucoma Absent
Rx NdYAG laser /ruby laser (Q
switched mode)
NdYAG laser /ruby laser

22. Mongolian spot
• Since birth
• Large blue to grey patch
• Buttocks and lumbosacral area
• almost all newborn babies of African and Asian origin
• Mongolian spots are benign skin markings, and are not
associated with any illnesses, complications or risk factors.
• There is no known prevention and they generally fade in a
few years and disappear by puberty. Though occasionally
they persist into adulthood, there is no need for treatment

23. Café aulait spots
• Neurofibrmatosis (von
recklinghausens d/s)
• Tuberous sclerosis
• MEN
• Albrights syndrome
• Fibrous dysplasia
• Fanconis anemia
• Leopard symfrome

24. Freckles
• Yellowish / brownish
macules of
hyperpigmentation seen in
exposed parts of skin

25. Freckles Lentigens
Increased melanin synthesis Increased mealnosomes
Sun exposed areas involved Anywhere
Sunexposure  accentuation No accentuation
a/w xeroderma pigmentosa PJ syndrome GI polyps /peri oral lentigens

26. Tuberous sclerosis
• Hypopigmented macules ("ash leaf spots'') of tuberous sclerosis are
associated with:-
• a. Shagreen patches (area of thick leathery skin on back & neck)
• b. Facial angiofibroma (adenoma sebaceum)
• c. Cafe au lait spots

27. Tuberous sclerosis
• Vogts triad
• MR
adenoma sebaceum
• Seizures

28. Benign neoplasm a/w TS
• Rhadbomyoma of myocardium
• Angiomyoma of
liver,kidney,pancreas
• Ependymoma
• Astrocytoma

29. Melasma
• Acquired
• a/w pregnancy and OCP
• Brown patch in maxillary and zygomatic
area

30. • Butterfly rash
• Spare nasolabial fold
• Well demarcated