Dermatology Flashcards
What is the Mx of Keloid Scars
Intralesional -Trimcinolone
Lesions over knuckles fused into a rough ring shape. Lesions on the trunk having a purple tinge to them.
Possible underlying HIV, Lymphoma.
What is your Dx.
Disseminated Granuloma Annulare
Multiple droplet rashes, preceded by viral infection with strep.
What is your Dx and mx
Guttate psoriasis
Mx: Topical steroids; with emollients; Phototherapy,
What the cutaneous manifestation of Sarcoid and how do you treat it
Lupus Perinio
Mx: Systemic Steroids
Inflammatory condition with callous lesions ; red to brown colour, with central atrophy ; typically in the shins of ppl with BG of diabetes
What is your Dx and Mx
Necrobiosis Lipodica
Mx:
Potent Topical Steroids
Immunomodulating drugs
NOTE:
The rash does NOT signify the severity of diabetes
What is your advice for someone with acne who wants to isoretinoin
Beta HCG- one month pre therapy and initiate contraception
( highly teratogenic )
What are the feature of Morphea
Uncertain cause
One or kore indurates plaques in females
Annular appearance
Sclerotic progress -> plaques go from thickens to atrophic
Usually seen in women
Mx: potent to very potent steroids
Phototherapy
Methotrexate
What are the key features of alopecia areata
Round bald patches ( mostly in scalp )
Common in BG of thyroid , vitiligo , atopic eczema
Spontaneous re-growth in 50%
Tropical steroids and intra lesions steroids can also be used
What is your DX ?
Aloepcia Areata
What is your diagnosis
Pyoderma Gangrenosum
What is pyoderma gangrenosum commonly associated with
IBD - most important
But also see. In RA, vasculitis, myeloma , type 1 DM
What is criteria for Dx Type 1 NF
- 6 or more cafe-au-lait macules >5 mm (prepuberal ) or >15 mm (post pubertal )
- 2 or more neurofibroma of any type or one plexiform
- freckling in the axillary or inguinal regions
-optic glioma - 2 or more list nodules in the iris
-distinctive osseous lesion of type1 NF, eg sphenoid dysplasia , thickening of long bone with or without pseudo arthrosis
-a 1st degree relative with type -1 NF
What is the rash and what is the usual history-compatibility antigen present
Erythema Nodosum
HLA- B27
What is your diagnosis
Lichen planus
( white streaks on the surface of the plaques )
What is the Mx of Tenia Corporis
1st line - Topical Antifungal
2nd Line- Systemic Antifungal if 1st fails
What are the common causative organism of impetigo
> Staph Aureus
Group A -Beta Haemolytic Streptococcus
What is the Mx if Lichen Planus
Topical Steroids ( Dermovat)
Which drug can cause blue /black rashes with greyish discolouration
Long term use of Minocycline
Note : see for hints of person being treated for rosacea as much cyclone is used to treat rosacea
What is your spot diagnosis
Traumatic Nail change
Pts don’t recall any trauma
Different colours like symmetrically and longitudinally suggest old hematoma
Note - absent hunchinson sign ( blue black discolouration of nail bed which seen in Sunungal Melanoma )
What is Lichen Planopilaris
Variant of lichen planus
What is your Dx ?
Atopic dermatitis
Mx:
topical emollients x 20 times a day +
Topical steroids
Avoid irritants such as soap, water, gloves
What is your Dx and Mx
Scalps Psoriasis
1st line - topical steroids potent
What is the advice on maternal steroid use and breast feeding
Safe upto 40mg /day
What is the cause of development of stria in Pregnancy
Cortisol
CKD Pt. exposed to Gadolinium based MRI scan. Following this, skin becomes woody and hard.
What is your Dx
Nephrogenic Systemic sclerosis
What is a common side effect of Minocycline
Increased skin pigmentation with blue-black or grey discolouration
What is a key feature of Lichen Amylodosis
Intensely itchy, hyperkeratotic, pigmented macules,
Itching drives further the amyloid deposits
Can be areas like the back
TX: Recduce itching ; antihistamines, topical steroids
Note:
In Lichen simplex chronics, the rash is in area that they common scratch ( like shins)
Where do you see Wickham’s Stria
Whitish streaks, extremely itchy
Lichen Planus
What is the best Mx of BCC
Surgical excision
What is the criteria for Moh’s Micrographic surgery
> Recurrent/incompletely excised BCC
Poor defined margins in primary BCC
Lesions in high risk areas such as ear, nose, eyelids, nasolabial folds
Cosmetic and functionally imp areas such as head and neck
Aggressive clinical evolution of subtype
What are the key features of Cutaneous Mastocytosis ( urticaria pigmentosa)
Polymorphic lesions
Flushing, diarrhoea, N/V
Raised IgE levels
Midly raised Tryptase
NOTE:
IF tryptase significantly increased >20ng/ml - Ix for systemic mastocytosis
What is the interaction between isoretinoin and carbazepine
Isoretinoin reduced the plasma coucernatrion of carbamazepine
What is the single most important prognostic factor of melanoma
Thickness of the melanoma
What is the diagnosis basis of melanoma
ABCDE rule
Assymery
Border irregularities
Colour ( more than 1)
Diameter >6mm
Evolution
What are some of the causes of Erythema Nodosum other than Sarcoidosis
throat infections due to streptococcus or viral infection, IBD, TB, Leprosy
What are the causes of Keratoderma Blenorrhagica
Seen in reactive arthritis
Caused by Chlamydia, Shigella, Salmonella, Campylobacter, Yersinia
What is the mx of psoriasis
1st- topical steroid
2nd- Vitamind D Topical
3rd - Combine 1st and 2nd
4th - UVB / Photherapy
5th ( Avoid If past H/o Cancer)
- Non biologics- Methotrexate*/ Ciclosprin
6th - Biologics (Etanercept)
what are the chomosomes affected in NF1 and NF2
NF1- Chr 17
NF2 - Chr 22
What is Kobner Phenomenon
he Koebner phenomenon (also known as isomorphic response) is when trauma or injury to the skin triggers the development of new lesions in a patient with a pre-existing skin condition.
This typically occurs in conditions like psoriasis, lichen planus, and vitiligo, pyoderma gangrenous
What are some of the complications of Nephrogenic Systemic Fibrosis
Pulm Fibrosis
Pulm HTN
Cardiomyopathy
What is the common skin rash seen in squamous cell Ca of oesophagus
Acrokeratosis Paraneoplastica
( Psoriatic type rash- affecting hands, fingers, feet, Nose, Ears)
Thick, red, scaly lesion in arms, thighs, buttocks, Central clearing with raised Edges
History of Aceclofenac use
What is your dx?
Erythema Annular Centrifugum
NOTE: They are seasonal, complete recovery and then can reappear after months the triggered due to infection, drug etc
Mx: Topical steroids
what is the histopath of erythema annular centrifugum
Focal parakeratosis and superficial and deep Perivascular mononuclear infiltrates with “characteristic cuffing in a coat sleeve pattern”
What is a key difference between erythema annular centrifugum and Erythema Gyratum Repens
In Erythema Gyratum Repens , the rash migrates rapidly at a speed of 1cm/day
The rash has woody grains like texture (Concentric erythematous bands)
which is NOT the case in erythema annular centrifugum
What is the rash seen in squamous cell Ca of Bronchus
Erythema Gyratum Repens
The rash has woody grains like texture (Concentric erythematous bands)
What is a key characteristic of Ptyriasis Rosea
Multiple tiny ova patches ( in trunks like Christmas tree fashion)
But preceded by large oval patch ( Herald patch) a few days- to weeks prior (1-2 weeks)
Flu like illness can precede the HeraldPatch
Can associated with reactivation of HSV 6 and 7
What is the pathophysiology of Toxic Epidermal Necrosis ( TEN)
Cytotoxic T cells and Apoptosis
What is a common case of Erythema multiform Minor
HSV1
How do you differentiate Erythema multiform Minor from Erythema multiform Major
Classic MRCP Question Stem Examples:
20-year-old with recent HSV, well-defined target lesions on hands and feet, no mucosal involvement → EM Minor
40-year-old on phenytoin, widespread target lesions, hemorrhagic oral ulcers, fever → EM Major (concern for SJS if >10% BSA detachment)
Brown colour pigmented rash in shins, with someone having tremors, sweating,
Pre-tibial Myxoedema -
What is your Dx
Granuloma Annulare
Spot diagnosis
Icthyosis Vulgaris
Note - autosomal dominant , scaly lesion , mutation of gene encoding profillagrin
What is the most common cause of erythema multiforme
HSV
What is a key thing to know that is different when doing excisions biopsy of melanoma
Excision biopsy with atleast 1cm clear margin
In normal cases - 1-3mm normally
What finger changes do you see in pretibial myxoedema
Acropachy ( clubbing )
Where do you see Koilonychia
Iron deficiency anemia ( spoon shaped nails)
Where do you see Leukonychia
In hypoalbuniemia
What causes Tinea Cruris
Trichophyton Rubrum
Seen in groin/ skin creases of groins
Can be seen in diabetics
Mx: topical ketoconazole - 1st
If topical fails, then oral ketoconazole
What causes molluscum contagiosum
Pox virus
What is your Dx
Plantar Warts
What is the inheritance of HHT
Autosomal dominant
What’s the cause of bleeding in HHT
Multiple AVM in brain / eyes/ lungs / gut / liver
Epsitaxis is due to abnormal dilated capillaries
How do you differentiate between the rashes in HHT and Peutz Jager Syndrome
HHT- rash will be red/ pink
PJ syndrome - black
Spot diagnosis
Lupus perinio ( seen in systemic sarcoidosis)
Mx : steroids
What is the Mx of dermatitis Herpetiformis in ppl who do not response to gluten free diet and Daposone
Oral Sulfapyridine
Spot diagnosis
Lupus vulgaris ( chronic TB infection of skin )
( also enlarging , infiltration plaque)
Seen in chronic tuberculosis infection
Mx: treat TB
What is the Mx of Lichen Planus
1) topical steroids
2) topical calcineurin inhibitors
3) oral steroids if systemic upset
What is your spot diagnosis
Granuloma Annulare
what is a good 1st line advice for ppl wit acne rosacea
Avoid triggers
What is a common cause of
peri-ungal squamous cell Ca on finger nail
HPV- 16
How do you diagnose Granuloma Annulare
Skin Biopsy - Necrobiotic collagen surrounded by palisading histiocytes and lymphocytic infiltrate
How do you treat Pemphigus Vulgaris
Oral steroids ( high dose ; 0.5-1.5mg/kg/day)
Note-
Phemphigus- mucous inv.
Phemphigoid - NO mucous inv
Spot diagnosis
Eruptive Xanthomas
( appear in the extensor surface as crops of small red yellow papules and are associated with triglyceridemia
( a potential cause of pancreatitis )
Spot diagnosis
Late onsent epidermal naevus ( birth mark )
Mainly seen in males ( triggered to develop in PUBERTY due to circulating androgens)
Note- congenital naevi at birth do NOT follow the Linear pattern as above
What is the medical cause for Albinism
Chediak-Higashi Syndrome
( Albinism, recurrent chest infections, peripheral neuropathy , nystagmus ; intellectual disability)
What can you use other than help with pain from herpes zoster activation 8 shingles) but Pt. presents post 72 hrs/ or already crusting is seen
Gabapentin
What are some of the key features of secondary syphilis
Alopecia, Multiple apthous ulcers, maculopauluar rash affecting entire trunk
How long do you have to to avoid pregnancy after trialling Acitretin (oral)
4 weeks prior to starting therapy and unto 3 years after stopping medication
What should you think of when the pt. seas that they can predict where the next rash will appear or have ‘suddenly appeared’
Dermatitis Artefacta
What can you use to treat mouth ulcers in S-J syndrome
Chlorhexidine mouth wash
Remove triggering drugs
NOTE:
NO role of topical steroid in S-J syndrome
What is the second line Mx of Pyoderma Gangrenous after trialing topical steroids
Topical Calcineurin inhibitors
( Tacrolimus)
What is a common cause of angular stomatitis
Iron Deficiency Anemia
What can you use to Treat Seborric dermatitis affecting skin/face
Selenium Sulfide
3rd trimester pregnancy
Urticaria rashes starting in around the stretch marks, later spreading to thighs and buttocks
What is your dx
Polymorphic eruption of pregnancy
aka
(Pruritic Urticarial papules and plaques of Pregnancy - PUPP)
Atopic eczema - Not responding to topical steroids
What is your dx
Topical calineurin inhibitors (Tacrolimus)
what is the Mx of SJ-Syndrome
Supportive
Remove triggers
IV fluids
what are the carriers of cutaneous Larva Migraines
Hook work infection
Domestic pets ( Dogs, Cats, cattle)
Mx: Albendazole, Ivermectin
What is HHT also known as
Osler-Weber-Rendu Syndrome
What is the best Diagtnostic tool for Tinea cruris
Micro examination of KOH treated skin scrapings
What is cutaneous mastocytosis also called as
Urticaria Pigmentosa
When do you use alignate based dressing for pressure sore.
Indications for Alginate Dressings in Pressure Sores:
✅ Moderate to heavy exudate – absorbs fluid and prevents maceration.
✅ Sloughy or necrotic wounds – helps debride by maintaining a moist environment.
✅ Cavity wounds – conforms to wound shape, ideal for deeper pressure ulcers.
✅ Bleeding wounds – promotes hemostasis by forming a gel when in contact with wound fluid.
When NOT to Use:
❌ Dry or low-exudate wounds – can dehydrate and delay healing.
❌ Infected wounds without additional antimicrobial treatment – may need silver-alginate dressings.
❌ Third-degree burns or very deep wounds with exposed bone – not effective in such cases.
When do you use hydrogel based dressing for pressure sore.
Pressure ulcer with slough, but minimal exudate
What is a common finger association with bronchiectasis
Yellow Nail Syndrome
What do you see In HSP on histology
IgA depsoiton !!
Note:
On bloods;
Plts, APTT, PT, will all be NORMAL!
What is the mx of shingles
If presents <72 hrs, oral aciclovir
What is Nikolsy sign
Nikolsky sign is a clinical dermatological sign used to assess skin fragility. It is positive when gentle lateral pressure on normal-appearing skin or at the edge of a lesion causes the epidermis to shear off, leading to blister formation or erosion.
Sudden, eruptive rash covering >90% of the body
Erythroderma
Multiple pin point macule and ‘cayne pepper spots’ in legs post strenuous exercise/ long distance running
What is your Dx
Capillaritis
What are some of the causes of Acanthuses Nigrans
Gastric Ca, Obesity, DM
how do you control active progressing vitiligo
Oral betamethasone ( pulsed therapy for 3-6 months on weekends)
+
Therapy with narrow band UVB
( NBUVB) therapy twice to thrive weekly
Spot diagnosis
Spot diagnosis
How frequent should you conduct surveillance in someone with confirmed Peutz-Jager syndrome for gut
Every 3 years with GI scopy
What does Xerosis mean
‘Dryg skin’
Commonly seen in CKD where ppl are having dialysis
the Uraemia can cause dry skin and itching
what are the features of myxoid cyst
Elderly patient with OA, painless swelling near DIP joint
Small, smooth cyst, clear gelatinous fluid on aspiration
Nail deformity present (e.g., longitudinal groove)
Positive transillumination, no inflammation
Spot diagnosis
Pyogenic granuloma
Pregnancy is a risk factor
Occurs at the site of penetrating injury
Rapid growth over normal skin
Mx; curatage with cautery or cryotherapy
Note:
If pt gives history of mole at the site prior to rapid growth, think of alternative Dx such as amelanotic malignant melanoma
What infection precedes guttate psoriasis
Infection with streptococcus
What is Darier Sign
Seen in mastocystosis
Acute reddening, swelling, blistering of lesions
Spot diagnosis
What are the features of bullous phempigoid
Tense , fluid filled blisters
Usually affects >80 years old and has an association with psoriasis and some neuro disorders such as dementia, CVD, PD
Mx: oral steroids
Spot diagnosis
Basal cell carcinoma
Subungal fibromas
Slow growing , painless tumours seen in nail fold
Round and feel elastic
Can cause complications when elevating nail and can cause erosion if distal phalanx
What are the feature of Subungal fibromas
Slow growing , painless tumours seen in nail fold
Round and feel elastic
Can cause complications when elevating nail and can cause erosion if distal phalanx
What is the first line mx for hydradenitis suppurativa
Oral tetracycline x for 12 weeks
If above Tx fails, then try
Oral clindamycin/rifampicin
For 10-12 weeks
What is erythroderma usually associated with or what does the Pt. Medically suffer with which lead to erythroderma
40% is secondary to eczema
25% is secondary to psoriasis
What’s is DRESS syndrome
Where do you see nail pitting
Psoriasis
What are some causes of vitiligo
Underlying autoimmune conditions,
Hypothyroid, Pernicious anemia
What is a key difference between albinism and vitiligo
Albinism - Has eye changes and Nystagmus
Vitiligo- Eye changes NOT seen
What is the Mx of Tenia Corporis
Topical Terbinafine or Topical Imidazoles ( ketoconazole/ itraconazaole)
What is a complication of pseudoxanthoma elasticum
GI hemorrhage
NOTE: gene affected in pseudoxanthma is ABCC6
Spot diagnosis
What is the 1st line Mx of Gutatte Psoriasis
Narrowband UVB phototherapy
Note: in Psoriasis/plaque psoriasis we use topical steroids / vit d analogies as first line
But in guttate psoriasis — phototherapy is first line
Oral Hairy Leukoplakia
Recurrent conjunctivitis with dendritic ulcer formation ( small vesicles around lid margins )
What’s is your Dx
HSV infection
What causes gas gangrene
Clostridium perfringens
Multiple hypopigmented, scaly macules on upper chest and back.
After sun exposure
What is your Dx
Ptyriasis Versicolor
Mallassezia Yeast
Mx: Ketoconazole shampoo
What is the difference between oculocutaneous albinism type1 and type3
Type1 - complete absence of melanin in hair,skin, eyes
Type3- reddish hair, blue gray eyes
What is MOA of Ustekinumab
Anti-IL12 and Anti-IL23
Which vitamin deficiency causes angular kelitis
Vitamin B2 ( riboflavin )
How do you treat phemphigoid Gestationis
Topical steroids
What is the histology in pyoderma ganrenosum
Neutrophil infiltration
Name some common drug induced photosensitivity
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