Dermatology Flashcards
Cells in epidermis
a) Keratinocytes
b) Melanocytes
c) Langerhans cells = antigen- presenting cells. Pale dendritic cells which contain
Birbeck granules on electron microscopy
d) Merkel cells- epidermal nerve cells.
epidermal appendages
Pilosebaceous follicles: hair plus sebaceous glands (which open into hair canal); occur everywhere except on palms and soles.
Apocrine sweat glands: modified sebaceous glands; open into hair follicle or directly
onto skin; localized to axillae, nipples, perineum, genitalia
Eccrine sweat glands: on whole skin surface; secrete clear fluid containing electrolytes; sympathetic innervation.
functions of skin
sensation physical protection temp regulation chemical protection and lubrication immunological hormonal- Sex hormone metabolism, Production of vitamin D display- cosmetic toxic substance excretion
pathological terms
Hyperkeratosis -thickening of stratum corneum (SC)
Acanthosis -thickening of stratum spinosum
Parakeratosis -nuclei retained in cell of thickened SC
Acantholysis -loss of adhesion between epidermal cells
what can be used in topical treatments
Wet dressing- physiological saline can be made at home (2 teaspoons salt/litre water);
potassium permanganate (crystals in water to make pale pink solution) - useful if infection is present
Active ingredients such as sulphur, coal tar or corticosteroids can be incorporated into some
of the above vehicles
unguentum) emulsificans (= UE, contains liquid paraffin, white vaseline and emulsifying waxes) and Ung. Emulsificans aquosum (UEA = UE + 20% water
Useful antiseptic preparations include
povidone-iodine (Betadine) cream or ointment, Furacin ointment (nitrofurazone- causes allergic contact dermatitis) Hibitane cream (chlorhexidene- causes irritant dermatitis, avoid in eczema) cream
Antibiotic ointments
Terramycin (oxytetracycline plus polymyxin B), Polysporin (polymyxin + bacitracin),
Bactroban (mupirocin) skin and nasal ointment
corticosteroids indications
include acute eczema, pemphigus vulgaris, systemic lupus erythematosus and leprosy reactions
what antibiotics for widespread, deep or severe skin infections. Most skin infections are mixed Staph and Strep.
Penicillin VK is usually note effective for both and is
poorly absorbed in adults and older children
erythromycin,
cloxacillin
anti fungals used in dermatology
Griseofulvin - effective only for dermatophytes
Nystatin - effective only for Candida
Amphotericin B – very useful for oral candidiasis.
Imidazoles: broad spectrum anti-fungal agents active against both yeasts and dermatophytes
Triazoles: Itraconazole (Sporonox) – used orally for candidiasis, deep fungi
Fluconazole - Mainly used for candidiasis
and cryptococcal meningitis.
Terbinafine – mainly for dermatophyte infections, including Amorolfine (Loceryl) - nail laquer used 1-2 times per week
other drugs used in dermatology
Retinoids- Inhibit keratinization, sebum secretion and
inflammation, teratogenic
Dapsone - very useful in
dermatology especially for dermatitis herpetiformis, pemphigoid, various pustular dermatoses and Vasculitis
5-Fluorouracil (Efudix): 5% cream used for removal of solar keratosis
which dz is vitiligo occasionally associated with
Hashimoto’s pernicious anaemia diabetes mellitus Addison’s hypoadrenalism alopecia areata
vitiligo Rx
Potent topical corticosteroid creams- try for 3 months only
PUVA (psoralen) (oral or topical) + UVA) or narrow band UVB
Sunscreens and cosmetic covers
cosmetic onchronosis facts
Due to the use of bleaching creams containing
hydroquinone
Worst on sun-exposed parts of face and neck; maximal on malar region andaround the eyes
impetigo
Lesions start as superficial, subcorneal, thin walled vesicles which soon rupture to exude serum (streptococci) or purulent (staphs) which dries to form crusts
Rx- Antiseptic or anti biotic ointments (e.g. Furacin, Terramycin, Polysporin,
Bactroban)
ecthyma
Same as impetigo but infection extends into dermis and lesions heal with scarring.
Most common on lower legs following insect bites or trauma.
Treatment: Always give systemic antibiotic such as erythromycin, cloxacillin or sulphonamide
(not tetracycline in children)
folliculitis
most common in the beard area (sycosis barbae) but may occur on any hairy part of the body.
Treatment: antiseptic lotions; antibiotics, topical and / or systemic
furuncles
Deep staphylococcal infection in and around hair follicle
Recurrent boils (furunculosis) underlying precipitating
factors- diabetes, other causes of immunosuppression and poor hygiene.
Treatment: Topical antiseptics, according to culture results, and treat carrier state in patient
and contacts
strep skin infx
cellulitis- deep diffuse dermal infection, ill circumscribed, usually warm and tender
with lymphadenitis
erysipelas -supf well circumscribed rash extending to the subcutaneous lymphatic vessels, common
sites face and legs
Treatment: I.V. penicillin
Eliminate source of infection
Common wart
raised nodular type common in children in whom they undergo spontaneous regression sooner or later.
Treatment- Topical irritants: e.g. lactic acid and salicyclic acid paints , silver nitrate sticks. If necessary freezing with liquid nitrogen or curettage with or without light
electrodessication
Home remedy: Cut lemon peel to size of warts
can apply 25% salicylic acid ointment under plaster
or paint with 20% formalin or monochloracetic acid in plantar wart
Plane warts
multiple flat warts on face or limbs usually in children and young adults.
Treatment- topical irritants: benzyl benzoate, retinoic acid. 5- fluorouracil cream, Lemon peel home remedy
Venereal warts
there may be warts in urethra, vagina or anus as well.
Treatment- Topical imiquimod
electrocauterization, freezing, CO2 laser
20% podophyllin- Do not use podophyllin on mucosal
surfaces or in pregnancy (absorption and toxicity).
molluscum contagiosum
Dome shaped papules with a central
umbilication through which a white cheesy material can be expressed.
Treatment: Topical imiquimod
produce local inflammation (after which they regress) by either inserting sharpened match stick dipped in phenol into central umbilication, or freezing with liquid N₂, or light curettage
rubbing on retinoic acid or benzyl benzoate 2-3 times daily
express contents with comedo expressor
herpes simplex
Primary infection: usually gingiva-stomatitis in infants Secondary infection: “fever blisters” (herpes febrilis, “cold sores”): mostly on face,
especially lips but may occur anywhere.
Recurrent herpes simplex: in some individuals; precipitated by fever, sun exposure,
menstruation etc. Mostly on
face, then genitalia, but may occur anywhere.
Generalized herpes simplex – mainly in immunosuppressed patients; vesicles are diffuse,
not grouped
Rx- valacyclovir/ famciclovir
herpes zoster
Zoster results from reactivation of latent virus in dorsal root ganglia of peripheral and cranial nerves
Mostly in adults and geriatrics
Highly suggestive of HIV infection in young persons
Rx- oral acyclovir /famciclovir/valaciclovir which should
be started in the first 72 hours
IV acyclovir for severe disseminated zoster
Antibiotics if secondarily infected
Eye consult for ophthalmic zoster
HIV drug sensitivity
Especially co-trimoxazole and anti-TB drugs (widespread erythematous maculo-papular and lichenoid drug rashes)
SJS and TEN due to drugs such as sulphonamides and HAART (especially efavirenz and nevirapine)
leprosy Rx
rifampicin, dapsone and clofazimin
Treatment must be continued during reactions
reactions in leprosy Rx
cell mediated- Corticosteroids started in high doses) and tapered slowly. For reversal reactions at least 6 months of corticosteroids required as
treatment perpetuates the reaction. Shorter corticosteroid treatment needed for downgrading
reactions
humoral- Mild cases- no treatment or anti-inflammatory drugs. Severe cases- systemic
corticosteroids, increased dose of clofazimine and thalidomide if available
what develops in humoral leprosy reaction
Erythema nodusum leprosum: painful skin nodules, neuritis, arthritis, uveitis, glomerulonephritis
true TB infx
Tuberculous chancre- Nodule or ulcer with enlarged regional nodes
Lupus vulgaris- mostly head and neck, often starts in nos
Warty tuberculosis- (tuberculosis verrucosa cutis) mainly on extremities; hyperkeratotic warty surface
Scrofuloderma- sinuses and fistulae on skin resulting from tuberculous abcess formation
in underlying organ- usually lymph node but may be bone or joint, most common in neck and axillae.
Tuberculous gummas- Multiple lesions resembling scrofuloderma, resulting from haematogenous spread.
Miliary TB- with HIV infection
immunolgoical reactions of TB
- Papulonecrotic tuberculides (PNT): Widespread, symmetrical, mostly over elbows, knees
and buttocks but anywhere. Papules, pustules, ulcers and round to oval atrophic scars
(so-called varioliform scars). - Nodular tuberculides- mainly on lower legs
Erythema nodosum and nodular Vasculitis
Erythema induratum- nodules with ulceration- mainly on calves. - Lichen scrofulosorum- small, firm papules, grouped or diffuse on trunk or limbs
cutaneous sarcoidosis
A. SUBACUTE, TRANSIENT- erythema nodosum on lower legs plus hilar
lymphadenopathy.
B. CHRONIC, PERSISTENT- skin lesions either localized or widespread sometimes associated with bone and/or lung involvement
Lupus pernio: name given to type of sarcoidosis presenting
with purplish plaques on nose, cheeks and ears.
eczema
An immunologically mediated inflammatory skin disorder characterized in its acute stage by vesicle formation in the epidermis
acute, subacute, chronic, exfoliative
atopic eczema
association with asthma, hayfever
raised serum IgE in some patients, Association
with dryness of skin and ichthyosis.
A relatively common type of eczema in infants and children.
seborrhoeic dermatitis
Sometimes elicited or aggravated by infection (Staph, Strep, Pityrosporum yeasts)
Mostly subacute or chronic with erythema and scaling but may become acute and weeping.
Scalp, face, presternal and moist and hairy flexures (axillae, groins) commonly affected
eczema elicited by various factors
local- Dryness, Infection, Contact dermatitis- Primary irritant or Allergic- e.g. nickel , Venous hypertension, Trauma, UVL, Sweating
systemic- Infections e.g. tonsillitis
Drugs e.g. penicillin
eczema Rx
AB- flucloxacillin jor clartithromtcin Corticosteroids- topical mostly; systemic only if severe and for shortest possible time. Ultraviolet light (UVB or PUVA), cyclosporine and azathioprine pimecrolimus (Elidel), tacrolimus
ptyriasis rosea
relatively common disease in young adults
tends to occur in minor epidemics, mostly in spring and
autumn
Rash characteristically involves trunk and proximal parts of extremities
Self- limiting within about 8 weeks
Treatment: Diluted corticosteroids creams and sun exposure may shorten attacks
lichen planus
Aetiology -unknown (but increasing association with certain drugs, e.g. thiazide diuretics, oral hypoglycea emic agents, methyldopa and anti-TB drugs reported).
Course- sudden onset; most cases subside within 3 months to 2 years, but many relapse
Clinical: Anywhere, but commonly on anterior aspects of wrists and ankles, wickams striae, koebner phenomenom
characteristic severe itch and violaceous colour
Treatment: topical corticosteroids, under occlusion where practical. If severe enough, oral
steroids.
Lichenoid Drug Eruptions
Rash resembles lichen planus but may be more severe and extensive; slow resolution after drug withdrawal.
Commonest drugs implicated are gold, antimalarials (chloroquine,
mepacrine), thiazide diuretics, antituberculotics (PAS, streptomycin, INH).
Also from external contact with photographic colour developers
psoriasis
Start at any age, mostly 20’s -30’s, unpredictable with spontaneous exacerbartions and remissions
Auspitz sign- on firmly scraping away the scale, underlying bleeding points (due to
dilated capillaries in dermal papillae) are seen.
Koebner phenomenom
psoriasis Provoking factors
Infection
Psychogenic factors – stress often aggravates
Trauma, e.g. sunburn
Drugs- antimalarials, lithium
Endocrine- tends to improve with pregnancy
psoriasis Rx
Rx- Topical applications: Coal tar, Corticosteroids, Calcipotriol, Tazarotene
Ultraviolet light- narrow band UVB or PUVA
Systemic therapy- Methotrexate, Synthetic vitamin A derivatives
Cyclosporin A
New therapies: biologics
NB Systemic steroids should only be used as crisis management in acute stages of severe erythrodermic or generalized pustular psoriasis, otherwise BEST AVOIDED.
urticaria
Causes: Often not found, but must always be sought
Infections: commonest in children, especially streptococcal tonsillitis
Drugs: especially aspirin, penicillin, ACE inhibitors Dietary: specific foods or additives (dyes
Parasites: intestinal, bilharziasis.
Physical urticarial: provoked by pressure, heat, cold
Rx- AB: Dapsone, Omezilumab
antihistamnines
corticosteroids
allergic vascultis
Type III reaction resulting in leukocytoclastic Vasculitis.
Causes:
a) Unknown – e.g. Henoch- Schonlein
b) infections such as tonsillitis or pyelonephritis
c) drugs
Erythema nodosum
More common in females. Two main forms:-
a) Classical, acute: Mainly young adults. Crops of deep, painful, warm nodules or plaques.
Lower legs, mainly shins (seldom elsewhere)
b) Chronic EN- (nodular Vasculitis): smaller nodules, more widespread, mainly on legs.
Causes: Immune – complex mediated.
- Bacterial infections especially streptococcal tonsillitis, sinusitis, dental sepsis; tuberculosis, Yersinia.
- Viral and chlamydial infections – often presenting as “flu”.
- Sacroidosis.
- Drugs- especially sulphonamides
Treatment: Remove cause. Symptomatic – analgesics, anti- inflammatories;
corticosteroids seldom help for long; potassium iodide by mouth helps some patients.
Fixed drug eruption
Lesions recur on same spot and increase in number and site with each successive attack. Typically large, round, well circumscribed, purplish, slatecoloured residual macules are seen between attacks
erythema multiform
target lesions mainly on face and extensor surfaces of limbs, especially knees and elbows but may occur anywhere.
a) Stevens- Johnson syndrome: widespread round blisters and erosions include skin eyes,
mouth, genitalia: some cases associated with Mycoplasma pneumonia.
b) Toxic epidermal necrolysis (TEN): generalized or locarized sheets of despuamation of
necrotic epidermis resembling burns
Causes:
- Infections- viral (commonly herpes simplex), bacterial, Mycoplasma.
- Drugs-especially sulphonamides and phenophtalein.
- L.E.
- Malignancy
- Radiotherapy and cytostatic drugs
Rx- remove cause, AB if secondary infx (macrolide, tetracycline, or azithromycin)
pemphigus vulgaris
Jewish race especially. Middle and old age, mostly 40-60 years, Relatively common in black South Africans.
Clinical: Often presents with erosions in mouth, no itch
Rx- High dose corticosteroids
azathioprine/cyclophosphamide/cylcosporien
bullous pemphigoid
Elderly, generally older than 60 years
Large bullae tend to occur over wide areas especially on upper arms and thigh, Mucosal lesions uncommon.
Treatment: Corticosteroids (lower doses than for pemphigus)
Additional dapsone often useful and steroid sparing
linear IgA dz
Chronic, recurrent, pruritic blisters mainly on limbs. Small peripheral rings of blisters around
central erythema are characteristic (“string of pearls”).
Relatively common in balck South African children
Treatment: Long-term dapsone 100mg/ day for adult, less for children according to age.
Children do well on dapsone alone but adults need prednisone and azathioprine in addition.
dermatitis herpetiformis
Clinical: age: 20-50 years, occasionally in childhood. Acute or gradual onset. Pruritus is
severe and often the initial symptom
The distribution is characteristic: extensor surfaces of the limbs, especially knees and elbows, shoulders, trunk and buttocks. Oral lesions are unusual. Most
patients have gluten-sensitive enteropathy
Treatment: Dapsone by mouth in lowest possible dose. Gluten free diet helpful in some
patients.
porphyria
Two main types in South Africa:
1. P variegate – SA genetic porpohyria
Quiescent phase: raised stool porphyrins
Acute attack: Porphobilinogen in urine
2. Porphyria cutanea tarda: - Liver disease mostly due to alcohol, in genetically
predisposed individuals.
- Raised urinary porphyrins.
Clinical: In both types photosensitivity results in hyperpigmentation and a weatherbeaten,
waxy, winkled facial appearance
Hirsutism is common
icthyosis
group of inherited disorders of eratinisation
characterized by dryness and scalines of the skin.
Ichthyosis vulgaris
Manifestations of ichthyosis in the newborn:
a) Collodion baby: diffuse, dry shiny membrane present at birth, subsequently cracks and peels off
b) Harlequin foetus is the most severe form form of ichthyosis. The neonate is encased in thick armour plate- like hypekeratotic epidermis transversed by deep polygonal fissures. Death usually occurs shortly after birth.
Treatment: Bland, greasy ointments e.g. Ung.emulsificans. Etretinate reserved for severe
cases.
palmo plantar keratoderma
sometimes seen in black African men. This type of punctate keratoderma may be
associated with increased sweating (hyperhidrosis) of the palms and soles
Treatment: reduce sweating e.g. with 10% formalin soaks, and pare corns with a blade.
Etretinate for very severe cases
yeasts
Candida albicans
- Skin and mucous membranes, more rarely internal organs
2. Pityrosporum orbiculare (ovale)- lipophilic yeast=Malassezia furfur
Skin surface- tinea (pityriasis) versicolor
Hair follicle- Pityrosporum folliculitis
dermatophytes
Human and animals affected. The fungi grow in keratin.
3 genera: - Microsporum – skin and hair
-Epidermaphyton – skin, mainly feet and groins
-Trichophyton- skin, hair and nails
depp fungal infx
- Sporotrichosis – S. schenkii
- Achinomycosis – A. Israeli
- Nocardiosis – N. asteroids
- Chromomycosis – Cladosporium carrionii, Fonsecaea pedrosoi etc.
- Mycetoma
candidiasis
endocrine- diabetes mellitus, pregnancy, drugs (the Pill, broad spectrum antibiotics, and corticosteroids
Mucosal candidiasis: “Thrush” – white flecks in mouth and throat
Cutaneous:
Typical lesions are small superficial white pustules on glazed red skin with outlying, satellite
pustules
Rx- nystatin, imidazoles, amphoteracin B
systemic- amphoteracin B, nystatin, fluconazole
tinea versicolor
Common in adults in hot climates. Mostly upper chest and back (greasy areas); also less
commonly on neck, abdomen, upper limbs, groins.
Treatment: topical selenium sulphide (Selsun), or 20% sodium thiosulphate solution (“hypo”), or topical imidazoles
Tinea capitis
Scalp, prepubertal children, very rare in adults
Treatment: Griseofulvin, terbinafine.
Topical antifungals- Whitfield’s ointment, imidazoles, etc not effective alone
Tinea corporis
body ringworm, more common in children, but also in adults, especially in HIV infection, Usually in males with tinea pedis
Tinea pedis (athlete’s foot)
Itch, scalling, vehicles; secondary infection common. Spreads by contact, including from floors
Treatment: topical antifungals; systemic griseofulvin or terbinafine if severe
Tinea unguium
Nailplates thickened, friable and opaque, or white
Treatment: griseofulvin, terbinafine (Lamisil) or itraconazole (Sporonox)
Tinea barbae
beard area; very rare; usually due to animal ringworm
Treatment: oral griseofulvin, terbinafine or itraconazole plus topical antifungals.
Pityriasis Amiantacea
is a reaction of the scals without erident cause.
it may complicate seborrhaic dermatitis, Paoriasis,
Lichen simplex.
- Occurs in young people < 25 years (girls).
sporotrichosis
Trauma, direct inoculation, usually from soil or plants. Suspect it in inflammatory skin lesions
not responsive to antibiotics. Two main types:
1) Lymphocitaneous- skin + lymphatics; nodules, ulceration, LINEAR, CENTRIPETAL
SPREAD, OFTEN UP A LIMB.
2) Cutaneous- “fixed” – single warty or ulcerated plaque.
Disseminated forms- cutaneous only or systemic, are rare.
Treatment: Potassium iodide by month for about 3 months. Start with 300mg/day (100mg
tds), increase to 600mg/day or more. Alternatively itraconazole
chromomycosis
Inaculation through minor injury, mostly on legs. Very slow growing warty plaques or
fungating masses. May extend to cover large areas.
Treatment: Surgical excision where possible; plus itraconazole or terbinafine.
nocardosis
Discharging sinuses on skin, usually from underlying lung or bone involvement. One cause
of Madura foot.
Treatment: Six months or longer of cotrimoxazole (Bactrim), sulphonamide or tetracyclines.
Can add potassium iodide.
actinomycosis
Endogenous, from mouth, GIT. Three main types: cervico-facial, abdominal and throracic.
Skin: nodules, abscesses, sinuses, “sulphur granules” in discharge.
Treatment: Penicillin for 6-12 months. Can add potassium iodide.
mycetoma
Commonest on feet, hence “Madura Foot”. Swelling, abscess formation, discharge.
Eumycetoma- surgery; poor response to chemotherapy (itraconazole, amphotericin B)
blastomycosis
Relatively rare in SA. Lungs, bones, skin: nodules, abscesses, sinuses, ulcers, granulomas.
Slowly progressive, may disseminate.
Treatment: itraconazole, amphotericin B.
scabies
Secondary infection is common. Main sites of
involvement are around axillae, wrists, webspaces of fingers and toes, genitalia and buttocks
NORWEGIAN SCABIES: Severe crusted, hyperkeratotic lesions, seen in mentally deficient
and immunosuppressed patients: contain myriads of mites. Very pruritic. Very contagious.
Treatment: Benzyl benzoate emulsion (Ascabiol) or 2% sulphur, ivermectn
pediculus capitis
Head lice cause epidemics in schoolchildren (even in Houghton).
Itchy and infected scalp lesions occur especially around the ears. Treatment consists of
gamma benzene hexachloride, Lyclear or Topical/oral Ivermectin
PEDICULUS CORPORIS: Mainly seen in tramps
pthirus pubis
Crab lice on pubic hairs and eyelashes. Treat former with Ascabiol and
use Vaseline for eyelashes. Permethrin shampoo, Lycur ereme/ rinse, or Gambex shampoo
acne vulgaris
face, upper back and chest, upper arms (rarely axillae and groins)
P. acnes produces Lipases & Proteases
Factors influencing acne vulgaris
Hormonal: androgens increase size of sebaceous glands
Genetic: Family history
Climate: UVL beneficial- improvement in summer
Psychological- exacerbation of existing lesions and neurotic excoriations.
Diet- controversial- ?? Aggravated by nuts, chocolates
Drugs- corticosteroids, iodides
Rx- benzoyl peroxide, retinoic acid, adapalene
Tetracyclin, erythromycin, co-trimoxazole
Systemic prednisone for severely inflammatory lesions- for short periods only
rosacea
Usually middle aged and elderly, mostly women with fair skin. Relatively common, confined to face. Vasomotor instability results in frequent flushing or blushing which leads to persistent erythema, oedema, telangiectasia and sebaceous hyperplasia
Rhinophyma may result.
Trigger factors: spicy food, red wine, hot coffe/ tea,
Eyes: blepharitis, conjunctivitis, keratitis.
perioral dermatitis
Mostly women childbearing age; males rarely affected.
Recurrent cycles with remissions and exacerbations. May be provoked, aggravated and perpetuated by topical steroids
Rx-Oral: Tetracyclines, Metronidazole (Flagyl), Ampicillin- not as effective
Topical:Sulphur cream or lotion 2%, Metronidazole Gel (Rosex)
Wean off any topical steroids rapidly
Plastic surgery or CO2 laser for rhinophyma
miliaria rx
loose cotton clothes, fans and air conditioners.
hidradenitis suppurativa
Chronic disease of apocrine glands in axillae, groins, sometimes in natal cleft and around anus
relapse is usual
Systemic retinoids not always helpful but must be tried. In females hormonal treatment as for severe acne may help.
Oral steroids, excision and grafting may be
needed.
Antibioties: Clindamycin + Rifampicin for at least 3-4 months.
androgenetic alopecia Rx
Minoxidil lotion
alopecia areata
Reassurance, topical irritants, e.g. tretinoin (Retin –A) or UVB, topical steroids.
Longterm PUVA- preferable for severe cases.
DO NOT GIVE SYSTEMIC CORTICOSTEROIDS
Trichorrhexis nodos
in hair damaged by bad perms, excessive bleaching, sun exposure
and excessive brushing, hair shafts may fracture, forming a frayed nodule where the shaft
then breaks off
dandruff
Pityrosporum ovale
growing on a greasy scalp, best treated with selenium sulphide shampoo (Selsum) or
Nizshampoo (ketoconazole). Medicated shampoos should be used intermittently, not
continuously – excessive use may cause dryness and hair loss. Moderate to severe dandruff
is usually associated with Seborrhoeic dermatitis or psoriasis of the scalp
leukonychia
Whiteness of nail plate which may be punctate (spotted), striate (in stripes), or total. Small
white spots in the nail plate are probably due to inapparent trauma and not to any dietary
deficiency of calcium or any other known cause. Longitudinal white bands are usually
congenital. (N.B. history). If acquired and transverse, look for systemic disease or drugs.
Irregular white patches are usually due to fungal infection which can be confirmed by
microscopic examination and culture of the nail plate.
pitting of nails cx
psoriasis or eczema
paronychia
Almost always due to too much working in water. Acute
cases are due to staphylococcal infection, chronic cases to candidia
lupus erythematous
hyperkeratosis, follicular plugging, epidermal atrophy, liquefaction degeneration of basal layer, pigment incontinence, perivascular and periadnexal infiltrate of lymphocytes
Subacute LE- Skin lesions more acute, annular, scaling, more widespread- face, arms and upper trunk.
Rx: Strong topical steroids, sunscreens, oral chloroquine (beware retinal damage: retinoids
for refractory cases)
Systemic LE (SLE)
Females: males 8:1
Multi-system disease – joints, kidneys, lungs, lymph glands, heart, CNS
Leukopaenia, anaemia, thrombocytopenia, renal dysfunction
Rx: Systemic steroids and immunosuppressives (cyclophosphamide and azathioprine),
chloroquine.
Drug induced SLE – like syndrome
Mainly systemic manifestations; atypical rashes. Clears after stopping causative drugs which
include methylopa, hydralazine, penicillamine, procainamide, INH, sulphonamides,
phenytoin, minocycline.
dermatomyositis
Two types- Juvenile and Adult. Adult type sometimes associated with underlying carcinoma
which must be carefully sought. Carcinoma far less common in children, where vasculitis
prevails
Treatment: prednisone, immunosuppressive drugs (methotrexate, azathioprine or
cyclophosphamide, cyclosporine), chloroquine
scleroderma
With systemic involvement- Systemic steroids and immunosuppressives (methotrexate, cyclophosphamide) in acute stage. PUVA may be useful.
No systemic involvement- none, or chloroquine, or Calcipotriol oint (Dovonex)- doubtful results.
Mixed connective tissue disease
Features of SLE, sleroderma, dermatomyositis. Severe Raynaud’s, oedema of hands,
arthritis, myositis, sclerodactaly, pulmonary hypertension, discoid LE type skin lesions;
RNP positive
Rx: steroids
venous HT
Due to valvular incompetence (mainly hereditary) or deep vein thrombosis, or both
REDUCE OEDEMA by bedrest and elevation in acute stage, later by elastic bandages and
stockings.
Vascular surgery if deep veins patent. Skin grafts for ulcers if needed. Wet dressings for
acute eczema and ulcers- saline, or potassium permanganate if infected. Antibiotics –
systemic for cellulitis; topical – (remember possibility of contact dermatitis). Topical
corticosteroids for eczema but NOT ON OR NEAR ULCERS (they cause vasoconstriction)
arterial occlusive dz
Ischaemia causes pain, coldness, pallor, and absent pulses if large vessels are involved. NB
pressure bandages contra-indicated.
Causes: arteriosclerosis (especially in diabetics), Burger’s disease, rheumatoid arthritis.
Freckles (ephelides)
small brown macules on sun0exposed skin, appear in childhood in
fair skinned individuals who sunburn easily. Due to increased pigment synthesis by
melanocytes (which are normal in number) in response to sunlight
Solar (actinic, senile) lentigines
Occur mainly on backs of hands and arms in elderly white people as multipkle
well demarcated brown macules, often angulated and branched. Old lesions may become
raised and warty and sesemble seborrhoeic keratosis
melanocytic naevi
Three stages in process of maturation:
a) Junctional- naevus cells attached to basal layer of epidermis; clinically lesions are
flat.
b) Compound – naevus cells also present in dermis; lesions more raised.
c) Intradermal – all naevus cells in dermis; lesions domeshaped
Treatment: Remove any mole of which patient complains. ALL removed moles must be examined histologically
solar keraatoses
Consist of superficial, flat, non-infiltrated, hyperkeratotic (therefore palpably rough)
hyperpigmented, ill-defined patches on sun damaged skin.
Treatment of solar keratosis: The treatment of choice in young persons is 5-fluorouracil
cream (EFUDIX) applied twice daily for about 3-4 weeks
bcc
Slowly invasive locally; virtually never
metastasizes. Very common on sun-exposed skin in whites. Characteristic histological
picture of islands of basal cells with peripheral palisading
Rx- either biopsy + cauterization
and curettage, or surgical excision, or radiotherapy after confirmatory biopsy.
scc
Malignant tumours derived from keratinocytes which tend to invade the dermis. Commonest
types occur on sun damaged skin and arise from solar keratosis- these are relatively benign
and easy to treat
malignant melanoma
Back is commonest site in both sexes.
Unless excised early while confined to epidermis , tends to cause widespread, fatal
metastases
