Dermatology

Squamous cell carcinoma
Malignant tumor of the epidermis
It is found on sun-exposed areas
Initially firm thickening of skin
A flash colored lesion
The hard nodules soon ulcerate
And ulcers have a characteristic everted edge

Squamous cell carcinoma

Basal cell carcinoma
Slowly growing plaque or nodule
Skin coloured, pink or pigmented
Varies in size from a few millimetres to several centimetres in diameter
Spontaneous bleeding or ulceration
Does not metastasise via lymph nodes or bloodstream

Basal Cell Carcinoma

Basal Cell Carcinoma

Melanoma
The cancer of melanocytes
Metastasizes and locally invade
A jet-black lesions without any hair
Diagnostic
Punch
Excisional biopsy
Treatment
Excision with margins
Chemo and radiation
Debulking

Melanoma

Melanoma
Red flag pointers

Herpes simplex on the lips
Vesicles on an erythematous base
Painful prodrome
Located mucocutaneous
Usually self-limiting within days or weeks
Conditions that this disease cause:
Fever blisters
HSV encephalitis
Genital ulcers
Treatment: acyclovir

Herpes zoster on the face
Hyperesthesia or a burning sensation in any division of the fifth nerve
especially the ophthalmic division
(ophthalmic herpes zoster)
Herpes zoster is infectious to people who have not previously had chickenpox
multiple, painful, unilateral vesicles and ulceration
increases with age and immunosuppression
Antiviral treatment can reduce pain and the duration of symptoms

Burns
Management depends on extent and depth
Degree:
First-degree – the skin may be red or gray, but capillary refill remains normal
Second-degree - blister formation
Third-degree burns are deeper and destroy skin appendages such as sweat glands, hair follicles, and sometimes pain receptors

Burns
The “Rule of Nines”
Head and arms: 9% each
Chest, back, and legs: 18% each
Patchy burns can be estimated by using one hand’s width as an estimate of 1% of body surface area burned

Burns clues to impending pulmonary and laryngeal edema
Soot in the mouth or nose
Stridor
Wheezing, a husky whisper
Altered mental status
Burned nasal hairs, hairs and eyebrows
Burns involving closed

Burn treatment
If patient has signs of severe respiratory injury, the first step is to intubate before more severe laryngeal edema can occur and make the intubation difficult.
If carboxyhemoglobin level is significantly elevated (>5–10%), administer 100% oxygen.
Fluid resuscitation over the first 24 hours.
Use Ringer’s lactate as the preferred fluid
Afterward, when the diffuse capillary leak improves, give enough fluid to maintain urine output >0.5–1 mL per kg per hour.
Give stress ulcer prophylaxis with H2 blocker or PPI.
To prevent infection, use topical treatment with silver sulfadiazine.
Do not break blisters and do not use steroids.

Multiply symmetrical subcutaneous lipomas
benign tumours of mature fat cells
situated in subcutaneous tissue
Soft and may be fluctuant
Well defined
Rubbery consistency
Painless
Most common on limbs (especially arms) and trunk
Can occur at any site

Neurofibromatosis type 1
von Recklinghausen disorder
Clinical features
Six or more café-au-lait spots
Freckling in the axillary or inguinal regions
Flesh-coloured cutaneous tumours
Hypertension
Iris hamartomas
Learning difficulty
Musculoskeletal problems
Optic nerve gliomas

Neurofibromatosis type 1

Adiposis dolorosa
obesity (most often) and chronic pain in the adipose tissue (for more than 3 months)
Multiple encapsulated fat overgrowths (lipomas) on the trunk and limbs
Painful subcutaneous plaques
Ecchymoses (bruises) without noticed trauma.
It usually appears between 35 and 50 years of age.
It may be more common in people with obesity.
Dercum disease

Dermoid cyst
The most common location for dermoid cysts is the lateral third of the eyebrows; however, they also may occur on the mid forehead, scalp, nose, anterior neck, and trunk.
they are caused by the implantation of epithelial tissue into another structure
dermoid cysts are made up of epidermal and dermal components: keratinocytes, hair follicles and hair, and sweat glands
Epidermoid cyst
Are similar in structure and origin to dermoid tumors and the two are often grouped together. Epidermoid tumors are lined with stratified squamous epithelium (skin) as dermoids are, but do not contain the additional skin appendages

Ingrowing toenail
the sides or corner of the toenail digs into the skin at the end or side of the toe
Mostly affects the outer edge of the big toe
Causes: ill-fitting shoes, improper trimming of toenails, injury near the nail, fungal infections of the nail, prescribed medications, abnormal nail shape

Ingrowing toenail

The end

Pilonidal Sinus
A pilonidal cyst is an abnormal pocket in the skin
usually contains hair and skin debris
located near the tailbone at the top of the cleft of the buttocks
Pilonidal cysts usually occur when hair punctures the skin and then becomes embedded
Pilonidal cysts most commonly occur in young men
the problem has a tendency to recur

Pilonidal Sinus
Simptoms
Pain
Reddening of the skin
Drainage of pus or blood from an opening in the skin
Foul smell from draining pus
Treatment
The cyst can be drained through a small incision or removed surgically

Pilonidal Sinus

Fixed drug eruption
trimethoprim
Treatment
To recognise the offending agent
and withdraw it
The rash should be treated according to its nature
The mechanism of fixed drug eruption is unknown
The most commonly affected areas are the face, hands and genitalia
appearance within hours of the drug’s administration
Drugs with the highest skin reaction rates
Penicillin and derivatives
Sulphonamides*
Trimethoprim*
Thiazide diuretics
Allopurinol*
Dapsone*
NSAIDs, esp. piroxicam*
Nevirapine*, abacavir*
Barbiturates
Quinidine
Anti-epileptics (phenytoin, lamotrigine*)
Blood products
Gold salts

Gout
a type of inflammatory arthritis
as a result of high levels of uric acid in the blood
It affects mostly middle-aged men (85%), but women become increasingly susceptible to gout after menopause
Certain events can precipitate gout: excessive alcohol ingestion, red meat intake, trauma and others
Diagnostic
Synovial fluid aspirate of affected joint, bursa or tophus → typical uric acid crystals using compensated polarised microscopy

Gout
Clinical features
acute attack: excruciating pain in great toe early hours of morning
skin over joint—red, shiny, swollen and hot
exquisitely tender to touch
relief with colchicine, NSAIDs, corticosteroids
can subside spontaneously (3–10 days) without treatment

Gout
good advice and patient education information
provision of rapid pain relief
preventing further attacks
prevention of destructive arthritis and tophi dealing with precipitating factors and comorbid conditions
The acute attack
NSAIDs (except aspirin), in full dosage
Corticosteroids: prednisolone
Colchicine: colchicine
Prevention: Allopurinol

Reiter syndrome
Reactive arthritis is joint pain and swelling triggered by an infection in another part of the body
Reactive arthritis usually targets your knees and the joints of your ankles and feet. Inflammation also can affect your eyes, skin and urethra
Symptoms:
Urethritis, joint pains, and occasional cutaneous manifestation, conjunctivitis

Reiter syndrome
Skin lesions
Waxy papules on soles, palms

Bilateral streptococcal cellulitis
Cellulitis is a common bacterial infection
a localised area of red, painful, swollen skin, and systemic symptoms
The most common bacteria causing cellulitis are Streptococcus pyogenes (two-thirds of cases) and Staphylococcus aureus (one third)
Clinical features:
Cellulitis can affect any site, most often a limb
It is usually unilateral; a bilateral disease is more often due to another condition
It can occur by itself or complicate an underlying skin condition or wound.

Cellulitis

Systemic lupus erythematosus

Systemic lupus erythematosus
DxT
Polyarthritis + fatigue + skin lesion

Bairnsdale’ ulcer (Buruli ulcer)
by the bacterium Mycobacterium ulcerans
usually begins as a painless papule or nodule that forms a necrotic ulcer over weeks to months
It occurs in specific geographic locations, namely coastal Victoria, Far North Queensland and the tropical regions of Central and West Africa
It has been speculated that the mycobacterial infection may follow an infected mosquito bit
People of any age can be affected, but most cases are among children aged less than 15 years
The limbs, particularly the lower limbs, are most commonly involved
Treatment: rifampicin and clarithromycin, excision and skin grafting

Actinic keratosis
Seborhhoeic keratosis

Actinic keratosis
Seborhhoeic keratosis
Actinic keratosis is a scaly spot found on sun-damaged skin
It is considered precancerous or an early form of cutaneous squamous cell carcinoma
usually easy to diagnose clinically or by dermoscopy
Treatment of an actinic keratosis requires removal of the defective skin cells
are not premalignant tumours
a common sign of skin ageing
over 90% of adults over the age of 60 years have one or more of them
can easily be removed if desired
reasons for removal may be that it is unsightly, itchy, or catches on clothing

Psoriasis
symmetrically distributed, red, scaly plaques with well-defined edges
The scale is typically silvery white
The most common sites are scalp, elbows, and knees, but any part of the skin can be involved
Factors that aggravate psoriasis
Streptococcal tonsillitis and other infections
Injuries such as cuts, abrasions, sunburn
Sun exposure in 10%
Obesity
Smoking
Excessive alcohol
Stressful event
Medications such as lithium, beta-blockers, antimalarials, nonsteroidal anti-inflammatories, and others
Stopping oral steroids or strong topical corticosteroids.

Tinea corporis
Spreading circular erythematous lesions
Slight scaling or vesicles at the advancing edge
Central areas usually normal
Mild itch
May involve hair, feet and nails

Atopic eczema
Dry skin
Cracks behind the ears or in other skin creases
Scaly areas that are red, inflamed and itchy
Thickened patches of skin from scratching
Small, raised bumps on the skin
Crusted, weeping or cracked skin
On face, neck and antecubital and popliteal fossae

Discoid lupus erithematosus
scaly, disk-like plaques on the scalp, face, and ears that may cause pigmentary changes, scarring and hair loss

Adverse drug reaction
an adverse skin reaction to a drug
antimicrobial agents, sulfa drugs, NSAIDs, chemotherapy agents, anticonvulsants, and psychotropic drugs
The onset of drug eruptions is usually within 2 weeks of beginning a new drug or within days if it is due to re-exposure to a certain drug
Itching is the most common symptom