Red scaly rashes Dr. D. Czarnecki MD MB BS

Red Scaly Rashes When someone presents with a red, scaly, itchy rashWhen someone presents with a red, scaly, itchy rash 1 Assume that he has dermatitis 2 Look for a raised edge 3 Look at the elbows and knees Dermatitis, psoriasis, or tinea are the most likely diagnoses for 90% of patients with red, scaly, itchy rashes.Dermatitis, psoriasis, or tinea are the most likely diagnoses for 90% of patients with red, scaly, itchy rashes.

Red Scaly Rashes Dermatitis (also called eczema) is the most common skin diseaseDermatitis (also called eczema) is the most common skin disease More than two out of three will develop it at some time in their livesMore than two out of three will develop it at some time in their lives It is more prevalent with age (as most diseases are)It is more prevalent with age (as most diseases are) It can vary in appearance depending on its severityIt can vary in appearance depending on its severity

Red Scaly Rashes Dermatitis on the legDermatitis on the leg There is no raised edgeThere is no raised edge The scale is thin and delicateThe scale is thin and delicate The leg is a common siteThe leg is a common site

Red Scaly Rashes TineaTinea There is a raised edge with a clearing centreThere is a raised edge with a clearing centre The buttocks are not a common siteThe buttocks are not a common site You must look at the feetYou must look at the feet

Red Scaly Rashes PsoriasisPsoriasis The scale is thick, silvery and easily comes away from the skinThe scale is thick, silvery and easily comes away from the skin The underlying skin has a pink colourThe underlying skin has a pink colour You must look at the elbows and kneesYou must look at the elbows and knees

Dermatitis You have made the diagnosis of dermatitisYou have made the diagnosis of dermatitis Begin treatment.Begin treatment. Prescribe an adequate quantity of an adequate strength glucocorticosteroidPrescribe an adequate quantity of an adequate strength glucocorticosteroid Recommend soap substitutesRecommend soap substitutes Recommend sun exposure (if possible)Recommend sun exposure (if possible) Review the patient in one weekReview the patient in one week If the patient is not better, you have made a mistakeIf the patient is not better, you have made a mistake

Red Scaly Rashes Dermatitis around the mouthDermatitis around the mouth Dermatitis responds to:Dermatitis responds to: glucocorticosteroids glucocorticosteroids emollients emollients ultraviolet light ultraviolet light Antihistamines are seldom neededAntihistamines are seldom needed Fine scale, red base, itchy

Dermatitis Glucocorticosteroids – become familiar with:Glucocorticosteroids – become familiar with: hydrocortisone 1% hydrocortisone 1% triamcinolone 0.02% triamcinolone 0.02% betamethasone valerate 0.05% betamethasone valerate 0.05% Ointments are more effective than creams but patients do not like using ointments – too greasyOintments are more effective than creams but patients do not like using ointments – too greasy Prescribe an adequate quantity – it takes 30 gms to cover the body oncePrescribe an adequate quantity – it takes 30 gms to cover the body once Use the rule of 9 – head - 9% of the surface area; back – 18%; chest – 9%; arm – 9%; thigh – 9%; leg – 9%Use the rule of 9 – head - 9% of the surface area; back – 18%; chest – 9%; arm – 9%; thigh – 9%; leg – 9%

Dermatitis Glucocorticosteroids are safe when applied to the skin.Glucocorticosteroids are safe when applied to the skin. Little is absorbedLittle is absorbed face – 7% face – 7% trunk or limbs – 1% trunk or limbs – 1% groin – 33% groin – 33% inflamed skin on the trunk absorbs about 5% - this returns to normal when the inflammation disappears inflamed skin on the trunk absorbs about 5% - this returns to normal when the inflammation disappears Plastic occlusion increases absorptionPlastic occlusion increases absorption

Red Scaly Rashes Review the patient in 1 weekReview the patient in 1 week The skin will be much improvedThe skin will be much improved If the patient is no better, you have made a mistakeIf the patient is no better, you have made a mistake There are not too many causes for failureThere are not too many causes for failure No better despite 3 weeks of using a glucocorticosteroid cream Note the raised edge

Dermatitis- no better The most common reasons for failure to improve despite using an adequate strength cream are:The most common reasons for failure to improve despite using an adequate strength cream are: ScabiesScabies TineaTinea A persistent antigenA persistent antigen A rare dermatosis is a less likely reasonA rare dermatosis is a less likely reason

Red Scaly Rashes Scabies causes itch and scratching causes dermatitisScabies causes itch and scratching causes dermatitis Look for burrows on the hands (wrists and between the fingers)Look for burrows on the hands (wrists and between the fingers) Anyone else in the family itchy?Anyone else in the family itchy? Treat for scabiesTreat for scabies A scabies burrow A fine, silvery track

Red Scaly Rashes Tinea has the raised edgeTinea has the raised edge The patient will tell you that the rash is spreadingThe patient will tell you that the rash is spreading You must look at the feetYou must look at the feet Take scrapings for fungal culture before antifungal agentsTake scrapings for fungal culture before antifungal agents Tinea of the face Spreading despite treatment with a glucocorticosteroid cream

Red Scaly Rashes Acute dermatitisAcute dermatitis Weeping has caused crusts – dried serumWeeping has caused crusts – dried serum This was caused by applying an antibiotic- glucocorticosteroid combinationThis was caused by applying an antibiotic- glucocorticosteroid combination He was allergic to the antibioticHe was allergic to the antibiotic An example of a persistent antigen preventing healing

Red Scaly Rashes Acute dermatitis that did not clear despite oral prednisolone. He also had rhinitis and blocked earsAcute dermatitis that did not clear despite oral prednisolone. He also had rhinitis and blocked ears It improved when he was off workIt improved when he was off work He polished black woodHe polished black wood He was allergic black wood and leaving work led to clearance of his skin, nose and ears.He was allergic black wood and leaving work led to clearance of his skin, nose and ears. He was continuously exposed to an antigen

Red Scaly Rashes A rarer dermatosisA rarer dermatosis Granuloma annulareGranuloma annulare There is no scaling therefore no epidermal componentThere is no scaling therefore no epidermal component A punch biopsy will confirm the diagnosisA punch biopsy will confirm the diagnosis An annular dermal eruption The surface is smooth

Assume that the rash is dermatitis Look for a raised edge Present? - look at the feet Take scrapings for fungal culture Prescribe cortisone of adequate strength Review in one week No better? – you have made a mistake Look at the elbows and knees Present? - psoriasis Scabies? A persistent allergen? A rarer dermatosis?

Red Scaly Rashes Some cases are followingSome cases are following Look at the slideLook at the slide Follow the flow chartFollow the flow chart Write down your answers to the questions before proceeding and see how well you do.Write down your answers to the questions before proceeding and see how well you do.

Red Scaly Rashes A cortisone cream of adequate strength was appliedA cortisone cream of adequate strength was applied Why is the rash no better?Why is the rash no better? She said that it was increasing in sizeShe said that it was increasing in size Write down your answers before you look at the next slideWrite down your answers before you look at the next slide

Red Scaly Rashes TineaTinea There is a raised edgeThere is a raised edge The centre has papules because a cortisone cream was used. This has suppressed the immune system and the fungus has persistedThe centre has papules because a cortisone cream was used. This has suppressed the immune system and the fungus has persisted You must look at the feet to see if there is a focus of infectionYou must look at the feet to see if there is a focus of infection

Red Scaly Rashes He is no better despite oral and topical cortisoneHe is no better despite oral and topical cortisone What could be the cause(s)?What could be the cause(s)? Write down your answers before you look at the next slideWrite down your answers before you look at the next slide

Red Scaly Rashes ScabiesScabies He has excoriated papules that are very itchyHe has excoriated papules that are very itchy Papules around the anus and genitalia are usually due to scabiesPapules around the anus and genitalia are usually due to scabies This is worse that is usual because of the use of cortisoneThis is worse that is usual because of the use of cortisone

Red Scaly Rashes The same patientThe same patient He has excoriated papules on the penisHe has excoriated papules on the penis Papules on the penis and scrotum are scabies until proved otherwisePapules on the penis and scrotum are scabies until proved otherwise His rash cleared with anti- scabetic therapy but the papules took longer to clearHis rash cleared with anti- scabetic therapy but the papules took longer to clear

Acute dermatitis – it is moist, there is no raised edge

Tinea – the raised edge is obvious

Scabies – nodules, the mite was seen on the wrist