Dermatology Flashcards
psoriasis
exacerbating factors
trauma
alcohol
drugs: beta blockers, lithium, antimalarials (chloroquine and hydroxychloroquine), NSAIDs and ACE inhibitors, infliximab
withdrawal of systemic steroids
Streptococcal infection may trigger guttate psoriasis.
what is stevens-johnson syndrome
severe systemic reaction affecting the skin and mucosa that is almost always caused by a drug reaction.
Causes of Steven-Johnson Syndrome
penicillin sulphonamides lamotrigine, carbamazepine, phenytoin allopurinol NSAIDs oral contraceptive pill
Features of Stevens-Johnston Syndrome
rash is typically maculopapular with target lesions being characteristic. May develop into vesicles or bullae
mucosal involvement
systemic symptoms: fever, arthralgia
Erythyma Nodosum
symmetrical, erythematous, tender, nodules which heal without scarring
most common causes are streptococcal infections, sarcoidosis, inflammatory bowel disease and drugs (penicillins, sulphonamides, oral contraceptive pill)
Pre-tibial myoxdema
symmetrical, erythematous lesions seen in Graves’ disease
shiny, orange peel skin
Pyoderma gangrenosum
initially small red papule
later deep, red, necrotic ulcers with a violaceous border
idiopathic in 50%, may also be seen in inflammatory bowel disease, connective tissue disorders and myeloproliferative disorders
Necrobiosis lipoidica diabeticorum
shiny, painless areas of yellow/red skin typically on the shin of diabetics
often associated with telangiectasia
Adverse effects of retinoids
teratogenicity
females should ideally be using two forms of contraception (e.g. Combined oral contraceptive pill and condoms)
dry skin, eyes and lips/mouth
the most common side-effect of isotretinoin
low mood
whilst this is a controversial topic, depression and other psychiatric problems are listed in the BNF
raised triglycerides
hair thinning
nose bleeds (caused by dryness of the nasal mucosa)
intracranial hypertension: isotretinoin treatment should not be combined with tetracyclines for this reason
photosensitivity
Lichen sclerosus
inflammatory condition which usually affects the genitalia and is more common in elderly females. Lichen sclerosus leads to atrophy of the epidermis with white plaques forming
Lichen sclerosis
features, management, F/u
Features
itch is prominent
The diagnosis is usually made on clinical grounds but a biopsy may be performed if atypical features are present*
Management
topical steroids and emollients
Follow-up:
increased risk of vulval cancer
Causes of fungal nail infections
Onychomycosis is fungal infection of the nails. This may be caused by
dermatophytes - mainly Trichophyton rubrum, accounts for 90% of cases
yeasts - such as Candida
non-dermatophyte moulds
Risk factors include for fungal nail infections include diabetes mellitus andincreasing age.
Features of fungal nail infections
‘unsightly’ nails are a common reason for presentation
thickened, rough, opaque nails are the most common finding
Differential diagnosis of fungal nail infections
psoriasis
repeated trauma
lichen planus
yellow nail syndrome
Investigations fungal nail infection
nail clippings
scrapings of the affected nail
the false-negative rate for cultures are around 30%, so repeat samples may need to be sent if the clinical suspicion is high
Management of fungal nail infections
do not need to be treated if it is asymptomatic and the patient is not bothered by the appearance
diagnosis should be confirmed by microbiology before starting treatment
dermatophyte infection:
oral terbinafine is currently recommended first-line with oral itraconazole as an alternative
6 weeks - 3 months therapy is needed for fingernail infections whilst toenails should be treated for 3 - 6 months
treatment is successful in around 50-80% of people
Candida infection:
mild disease should be treated with topical antifungals (e.g. Amorolfine) whilst more severe infections should be treated with oral itraconazole for a period of 12 weeks
if topical topical treatment is given treatment should be continued for 6 months for fingernails and 9-12 months for toenails
Large vessel vasculitides
temporal arteritis
Takayasu’s arteritis
Medium vessel vasculitides
polyarteritis nodosa
Kawasaki disease
small vessel vasculititides
ANCA associated
granulomatosis with polyangiitis (Wegener’s granulomatosis)
eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome)
microscopic polyangiitis
small vessel vasculititides
immune complex small-vessel vasculitis
Henoch-Schonlein purpura
Goodpasture’s syndrome (anti-glomerular basement membrane disease)
cryoglobulinaemic vasculitis
hypocomplementemic urticarial vasculitis (anti-C1q vasculitis)
Lichen planus
itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms
rash often polygonal in shape, with a ‘white-lines’ pattern on the surface (Wickham’s striae)
Koebner phenomenon may be seen (new skin lesions appearing at the site of trauma)
oral involvement in around 50% of patients: typically a white-lace pattern on the buccal mucosa
nails: thinning of nail plate, longitudinal ridging
Lichenoid drug eruptions - causes:
gold
quinine
thiazides
Management of Lichen Planus
potent topical steroids are the mainstay of treatment
benzydamine mouthwash or spray is recommended for oral lichen planus
extensive lichen planus may require oral steroids or immunosuppression
What is Dermatitis Herpetiformis?
Dermatitis herpetiformis is an autoimmune blistering skin disorder associated with coeliac disease. It is caused by deposition of IgA in the dermis.
Features of Dermatitis Herpetiformis
itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks)
Diagnosis of Dermatitis Herpetiformis
Skin biospy
Management of Dermatitis Herpetiformis
gluten-free diet
dapsone
What is bullous pemphigoid
Bullous pemphigoid is an autoimmune condition causing sub-epidermal blistering of the skin. This is secondary to the development of antibodies against hemidesmosomal proteins BP180 and BP230.
Features of Bullous pemphigoid
Bullous pemphigoid is more common in elderly patients. Features include
itchy, tense blisters typically around flexures
the blisters usually heal without scarring
there is usually no mucosal involvement (i.e. the mouth is spared)*
Skin biopsy
immunofluorescence shows IgG and C3 at the dermoepidermal junction
Management of Bullous Pemphigoid
referral to a dermatologist for biopsy and confirmation of diagnosis
oral corticosteroids are the mainstay of treatment
topical corticosteroids, immunosuppressants and antibiotics are also used
Pemphgoid vs pemphigus
Pemphigoid = skin only
Pemphigus = skin and mucosa
retinoid adverse effects (isotretinoin)
hair thinning, low mood, teratogenicity, dry skin/eyes/mouth, nose bleeds, intracranial hypertension, photosensitivity
Typical history of erythema multiforme
an adult with erythematous target lesions on the hands which later spread to the torso following a herpes simplex infection
Typical history of bullous pemphigoid
an elderly women develops itchy, tense blisters around the flexures. There is no mucosal involvement
what is acanthosis nigricans
Describes symmetrical, brown, velvety plaques that are often found on the neck, axilla and groin.
Porphyria cutanea tarda
Associated with hep C
blisters, onycholysis (painless detachment of the nail from the nail bed), hyperpigmentation and hypertrichosis.
Pompholyx (dyshidrotic) eczema
typically presents on the inside of the fingers, palms, toes rather than the dorsum of the hand or the face. Again it can cause blisters (and is relatively common)
Management of Impetigo - topical
topical fusidic acid
topical mupirocin should be used if fusidic acid resistance is suspected
MRSA is not susceptible to either fusidic acid or retapamulin. Topical mupirocin should, therefore, be used in this situation
Acanthosis nigricans
Describes symmetrical, brown, velvety plaques that are often found on the neck, axilla and groin.
insulin resistance → hyperinsulinemia → stimulation of keratinocytes and dermal fibroblast proliferation via interaction with insulin-like growth factor receptor-1 (IGFR1)
Associated with gastric adenocarcinoma
Causes of acanthosis nigricans
type 2 diabetes mellitus gastrointestinal cancer obesity polycystic ovarian syndrome acromegaly Cushing's disease hypothyroidism familial Prader-Willi syndrome drugs combined oral contraceptive pill nicotinic acid
Skin associations of gastric squamous cell carcinoma
Most associated with acrokeratosis paraneoplastica, in regards to cutaneous manifestations.
Features of Rosecea
nose, cheeks and forehead
flushing, erythema, telangiectasia → papules and pustules
Treatment of keloid scars
early keloids may be treated with intra-lesional steroids e.g. triamcinolone
excision is sometimes required
Treatment of keloid scars
early keloids may be treated with intra-lesional steroids e.g. triamcinolone
excision is sometimes required
Treatment of keloid scars
early keloids may be treated with intra-lesional steroids e.g. triamcinolone
excision is sometimes required
Treatment of keloid scars
early keloids may be treated with intra-lesional steroids e.g. triamcinolone
excision is sometimes required
Treatment of keloid scars
early keloids may be treated with intra-lesional steroids e.g. triamcinolone
excision is sometimes required
Treatment of keloid scars
early keloids may be treated with intra-lesional steroids e.g. triamcinolone
excision is sometimes required
Pompholyx eczema (also known as dyshidrotic dermatitis)
Common condition characterised by an intensely pruritic vesicular eruption on the palms and soles.
Triggers:
- humidity e.g. increased sweating
- irritants e.g. water, detergents, metals (nickel)
- lifestyle e.g. smoking
- drug use e.g. aspirin and COCP
- fungal infections
Causes of scarring alopecia
trauma, burns radiotherapy lichen planus discoid lupus tinea capitis*
Causes of non-scarring alopecia
male-pattern baldness
drugs: cytotoxic drugs, carbimazole, heparin, oral contraceptive pill, colchicine
nutritional: iron and zinc deficiency
autoimmune: alopecia areata
telogen effluvium
hair loss following stressful period e.g. surgery
trichotillomania
Dermatitis herpetiformis
Dermatitis herpetiformis is an autoimmune blistering skin disorder associated with coeliac disease. It is caused by deposition of IgA in the dermis. Associated with coeliac
Features
itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks)
Diagnosis
skin biopsy: direct immunofluorescence shows deposition of IgA in a granular pattern in the upper dermis
What is erythema nodosum
inflammation of subcutaneous fat
typically causes tender, erythematous, nodular lesions
usually occurs over shins, may also occur elsewhere (e.g. forearms, thighs)
usually resolves within 6 weeks
lesions heal without scarring
Causes of erythema nodosum
infection streptococci tuberculosis brucellosis systemic disease sarcoidosis inflammatory bowel disease Behcet's malignancy/lymphoma drugs penicillins sulphonamides combined oral contraceptive pill pregnancy
Causes of onycholysis (nail detaching from nail bed)
idiopathic
trauma e.g. Excessive manicuring
infection: especially fungal
skin disease: psoriasis, dermatitis
impaired peripheral circulation e.g. Raynaud’s
systemic disease: hyper- and hypothyroidism
urticaria pigmentosa
erythematous rash described above over the scapular and pectoral regions. Palpation of the lesions caused the skin around each lesion to become erythematous
Systemic mastocytosis
Systemic mastocytosis results from a neoplastic proliferation of mast cells
Features urticaria pigmentosa - produces a wheal on rubbing (Darier's sign) flushing abdominal pain monocytosis on the blood film
Diagnosis
raised serum tryptase levels
urinary histamine
Darier’s sign
Rash becomes itchy, raised and erythematous after being touched.
Associated with urticaria pigmentosa and systemic mastocytosis
Zinc deficiency
Associated with TPN perioral dermatitis: red, crusted lesions acrodermatitis alopecia short stature hypogonadism hepatosplenomegaly geophagia (ingesting clay/soil) cognitive impairment
Livedo reticularis
purplish, non-blanching, reticulated rash caused by obstruction of the capillaries resulting in swollen venules
Causes of livedo reticularis
idiopathic (most common) polyarteritis nodosa systemic lupus erythematosus cryoglobulinaemia antiphospholipid syndrome Ehlers-Danlos Syndrome homocystinuria
Erythroderma
Erythroderma is a term used when more than 95% of the skin is involved in a rash of any kind.
Causes of erythroderma
eczema psoriasis drugs e.g. gold lymphomas, leukaemias idiopathic
Erythrodermic psoriasis
may result from progression of chronic disease to an exfoliative phase with plaques covering most of the body. Associated with mild systemic upset
more serious form is an acute deterioration. This may be triggered by a variety of factors such as withdrawal of systemic steroids. Patients need to be admitted to hospital for management
Pyoderma gangrenosum
Associated with IBD and around a stoma
typically on the lower limbs
initially small red papule
later deep, red, necrotic ulcers with a violaceous border
may be accompanied systemic symptoms e.g. Fever, myalgia
Management of pyoderma gangrenosum
the potential for rapid progression is high in most patients and most doctors advocate oral steroids as first-line treatment
other immunosuppressive therapy, for example ciclosporin and infliximab, have a role in difficult cases
Causes of pyoderma gangrenosum
idiopathic in 50% inflammatory bowel disease: ulcerative colitis, Crohn's rheumatoid arthritis, SLE myeloproliferative disorders lymphoma, myeloid leukaemias monoclonal gammopathy (IgA) primary biliary cirrhosis
most common malignancy of lower lip
SCC
significant sun exposure and smoking history
Erythema multiforme
hypersensitivity reaction
target lesions
initially seen on the back of the hands / feet before spreading to the torso
upper limbs are more commonly affected than the lower limbs
pruritus is occasionally seen and is usually mild
Causes of erythema multiforme
viruses: herpes simplex virus (the most common cause), Orf*
idiopathic
bacteria: Mycoplasma, Streptococcus
drugs: penicillin, sulphonamides, carbamazepine, allopurinol, NSAIDs, oral contraceptive pill, nevirapine
connective tissue disease e.g. Systemic lupus erythematosus
sarcoidosis
malignancy
Management of scabies
permethrin 5% is first-line
malathion 0.5% is second-line
give appropriate guidance on use (see below)
pruritus persists for up to 4-6 weeks post eradication
Features of scabies
widespread pruritus
linear burrows on the side of fingers, interdigital webs and flexor aspects of the wrist
in infants, the face and scalp may also be affected
secondary features are seen due to scratching: excoriation, infection
Lichen planus
planus: purple, pruritic, papular, polygonal rash on flexor surfaces. Wickham’s striae over surface. Oral involvement common
Lichen sclerosis
itchy white spots typically seen on the vulva of elderly women
Features of lichen planus
itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms
rash often polygonal in shape, with a ‘white-lines’ pattern on the surface (Wickham’s striae)
Koebner phenomenon may be seen (new skin lesions appearing at the site of trauma)
oral involvement in around 50% of patients: typically a white-lace pattern on the buccal mucosa
nails: thinning of nail plate, longitudinal ridging
Causes of lichen planus
Gold
quinine
thiazides
Management of lichen planus
potent topical steroids are the mainstay of treatment
benzydamine mouthwash or spray is recommended for oral lichen planus
extensive lichen planus may require oral steroids or immunosuppression
Superficial spreading melanoma
Most common - 70% of cases
Typically affects arms, legs, back and chest, young people
A growing moles with diagnostic features listed above
Nodular melanoma
Second most common and MOST aggressive subtype
Sun exposed skin, middle aged
Red or black lump or lump which bleeds or oozes
Lentigo maligna melanoma
Less common
Chronically sun exposed elderly pts
Acral lentiginous melanoma
Rare form of melanoma
Nails, palms or soles, African Americans or Asians
Subungual pigmentation (Hutchinson’s sign) or on palms or feet
Important investigation of erythema nodosum
CXR to exclude sarcoidosis and TB
Keratoacanthoma
Features - said to look like a volcano or crater
initially a smooth dome-shaped papule
rapidly grows to become a crater centrally-filled with keratin
Spontaneous regression of keratoacanthoma within 3 months is common, often resulting in a scar. Such lesions should however be urgently excised as it is difficult clinically to exclude squamous cell carcinoma. Removal also may prevent scarring.
Dermetitis artefacta aka factitious dermatitis
Linear, well-demarcated skin lesions that appear suddenly, with ‘la belle indifference’
Risk factors of dermatitis artefacta
dermatitis artefacta is strongly associated with personality disorder, dissociative disorders and eating disorders
the prevalence of dermatitis artefacta is up to 33% in patients with bulimia or anorexia
Clinical features of dermatitis artefacta
patients typically present with linear/geometric lesions that are well-demarcated from normal skin. The appearance of lesions depends on the mechanism of injuries which may be either (scratching with fingernails or other objects, burning skin with cigarettes) or chemical (deodorant spray)
skin lesions are typically described to appear suddenly e.g. overnight. They usually appear whole and complete and do not evolve over time. There may be multiple lesions at various stages of healing
commonly affected areas are the face (especially cheeks) and the dorsum of the hands
despite the severity of skin lesions, patients may be nonchalant, displaying ‘la belle indifference’ (also known as Mona Lisa smile)
In the history, there may be recent life events or triggers such as a marital dispute or recent bereavement
Pellagra (B3 niacin deficiency)
3 D’s - dermatitis, dementia and diarrhoea
Pellagra may occur as a consequence of isoniazid therapy (isoniazid inhibits the conversion of tryptophan to niacin) and it is more common in alcoholics.
Features dermatitis (brown scaly rash on sun-exposed sites - termed Casal's necklace if around neck) diarrhoea dementia, depression death if not treated
Adverse effects of isotretinoin
teratogenicity - females MUST be taking contraception low mood dry eyes and lips raised triglycerides hair thinning nose bleeds
Eczema herpeticum
Eczema herpeticum describes a severe primary infection of the skin by herpes simplex virus 1 or 2.
It is more commonly seen in children with atopic eczema and often presents as a rapidly progressing painful rash.
On examination, monomorphic punched-out erosions (circular, depressed, ulcerated lesions) usually 1–3 mm in diameter are typically seen.
As it is potentially life-threatening children should be admitted for IV aciclovir.
Risk factors for squamous cell carcinoma
excessive exposure to sunlight / psoralen UVA therapy
actinic keratoses and Bowen’s disease
immunosuppression e.g. following renal transplant, HIV
smoking
long-standing leg ulcers (Marjolin’s ulcer)
genetic conditions e.g. xeroderma pigmentosum, oculocutaneous albinism
Minocycline
Used for treatment of acne vulgaris
Can cause irreversible skin pigmentation so is second line
Hereditary haemorrhagic telangiectasia (aka Osler-Weber-Rendu syndrome)
Autosomal dominant skin condition 2-3 needed for diagnosis
Epistaxis : spontaneous, recurrent nosebleeds
telangiectases: multiple at characteristic sites (lips, oral cavity, fingers, nose)
visceral lesions: for example gastrointestinal telangiectasia (with or without bleeding), pulmonary arteriovenous malformations (AVM), hepatic AVM, cerebral AVM, spinal AVM
family history: a first-degree relative with HHT
Crusted scabies
seen in patients who are immunosuppressed (esp HIV)
treat with ivermectin
Seborrheic dermatitis in adults
Associated with HIV and Parkinson’s
caused by an inflammatory reaction related to a proliferation of a normal skin inhabitant, a fungus called Malassezia furfur (formerly known as Pityrosporum ovale). It is common, affecting around 2% of the general population.
Features of seborrheic dermatitis
eczematous lesions on the sebum-rich areas: scalp (may cause dandruff), periorbital, auricular and nasolabial folds
otitis externa and blepharitis may develop
Scalp management of seborrheic dermatitis
over the counter preparations containing zinc pyrithione (‘Head & Shoulders’) and tar (‘Neutrogena T/Gel’) are first-line
the preferred second-line agent is ketoconazole
selenium sulphide and topical corticosteroid may also be useful
Facial and body management of seborrheic dermatitis
topical antifungals: e.g. ketoconazole
topical steroids: best used for short periods
difficult to treat - recurrences are common
Pathophysiology of bullous pemiphigoid
Bullous pemphigoid is an autoimmune condition causing sub-epidermal blistering of the skin. This is secondary to the development of antibodies against hemidesmosomal proteins BP180 and BP230.
Features of bulluous pemphigoid
elderly
itchy, tense blisters typically around flexures
the blisters usually heal without scarring
there is usually no mucosal involvement (i.e. the mouth is spared)*
Features of pemphigoid vulgaris
30-60 year olds
flaccid blisters
mucosal involvement
Erosions are a common presenting complaint as the thin, flaccid vesicles will easily rupture with friction.
Phenytoin and hair
causes hirsuitism not alopecia
Allergic contact dermatitis
type IV hypersensitivity reaction. Uncommon - often seen on the head following hair dyes. Presents as an acute weeping eczema which predominately affects the margins of the hairline rather than the hairy scalp itself. Topical treatment with a potent steroid is indicated
irritant contact dermatitis
common - non-allergic reaction due to weak acids or alkalis (e.g. detergents). Often seen on the hands. Erythema is typical, crusting and vesicles are rare
Management of venous ulceration
compression bandaging, usually four layer (only treatment shown to be of real benefit)
oral pentoxifylline, a peripheral vasodilator, improves healing rate
small evidence base supporting use of flavinoids
little evidence to suggest benefit from hydrocolloid dressings, topical growth factors, ultrasound therapy and intermittent pneumatic compression
Dermatitis herpetiformis
IgA deposition in the dermis
autoimmune blistering seen in coeliac disease
itchy, vesicular skin lesions on the extensor surfaces (e.g. elbows, knees, buttocks)
immune-related adverse events in patients on check point inhibitors - management
Oral steroids
Checkpoint inhibitors
e.g. Nivolumab used in metastatic melanoma
Mohs surgery
Micrographic surgical technique that involves lab analysis during the operation
Used for SCC and BCC
Morphoeic basal cell carcinoma
These are a type of BCC which present with firm/rough/waxy patches often on the cheeks. They often have poorly defined edges.
Granuloma annulare
papular lesions that are often slightly hyperpigmented and depressed centrally
typically occur on the dorsal surfaces of the hands and feet, and on the extensor aspects of the arms and legs
Associated with DM
Healing of erythema nodosum
with steroids should heal without scarring in 1-2 months
Conditions associated with yellow nail syndrome
congenital lymphoedema
pleural effusions
bronchiectasis
chronic sinus infections
What is toxic epidermal necrolysis
a potentially life-threatening skin disorder that is most commonly seen secondary to a drug reaction. In this condition, the skin develops a scalded appearance over an extensive area. Some authors consider TEN to be the severe end of a spectrum of skin disorders which includes erythema multiforme and Stevens-Johnson syndrome,
features of toxic epidermal necrolysis
systemically unwell e.g. pyrexia, tachycardic
positive Nikolsky’s sign: the epidermis separates with mild lateral pressure
Drugs known to induce toxic epidermal necrolysis
phenytoin sulphonamides allopurinol penicillins carbamazepine NSAIDs
Management of toxic epidermal necrolysis
stop precipitating factor
supportive care
often in an intensive care unit
volume loss and electrolyte derangement are potential complications
intravenous immunoglobulin has been shown to be effective and is now commonly used first-line
other treatment options include: immunosuppressive agents (ciclosporin and cyclophosphamide), plasmapheresis
Pemphigoid gestationis
pruritic blistering lesions
often develop in peri-umbilical region, later spreading to the trunk, back, buttocks and arms
usually presents 2nd or 3rd trimester and is rarely seen in the first pregnancy
oral corticosteroids are usually required
Polymorphic erruption of pregnancy
pruritic condition associated with last trimester
lesions often first appear in abdominal striae
management depends on severity: emollients, mild potency topical steroids and oral steroids may be used
Atopic eruption of pregnancy
is the commonest skin disorder found in pregnancy
it typically presents as an eczematous, itchy red rash.
no specific treatment is needed
Melasma
‘mask of pregnancy’
skin condition characterized by brown or blue-gray patches or freckle-like spots. Melasma happens because of overproduction of melanin
Pompholyx
Pompholyx is a type of eczema which affects both the hands (cheiropompholyx) and the feet (pedopompholyx). It is also known as dyshidrotic eczema.
Pompholyx eczema may be precipitated by humidity (e.g. sweating) and high temperatures.
Features of pompholyx
small blisters on the palms and soles pruritic often intensely itchy sometimes burning sensation once blisters burst skin may become dry and crack
Management of pompholyx
cool compresses
emollients
topical steroids
Skin conditions associated with diabetes
Infection Grannulare annulum Necrobiosis lipidocia Neuropathic ulcers Vitiligo Lipoatrophy
Features of zinc deficiency
perioral dermatitis: red, crusted lesions acrodermatitis alopecia short stature hypogonadism hepatosplenomegaly geophagia (ingesting clay/soil) cognitive impairment
Treatment of guttate psoriasis
Most cases resolve spontaneously within 2-3 months
Topical agents as per psoriasis
UVB phototherapy
Erythrasma
Erythrasma is a generally asymptomatic, flat, slightly scaly, pink or brown rash usually found in the groin or axillae. It is caused by an overgrowth of the diphtheroid Corynebacterium minutissimum
Examination with Wood’s light reveals a coral-red fluorescence.
Topical miconazole or antibacterial are usually effective. Oral erythromycin may be used for more extensive infection
