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Blotches: Light rashes. Medical Student Core Curriculum in Dermatology. Last updated April 18, 2011. Module Instructions.
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Blotches:Light rashes Medical Student Core Curriculum in Dermatology Last updated April 18, 2011
Module Instructions • The following module contains a number of blue, underlined terms which are hyperlinked to the dermatology glossary, an illustrated interactive guide to clinical dermatology and dermatopathology. • We encourage the learner to read all the hyperlinked information.
Goals and Objectives • The purpose of this module is to help medical students develop a clinical approach to the evaluation and initial management of patients presenting with light rashes. • After completing this module, the medical student will be able to: • Identify and describe the morphology of common light rashes • Describe the use of Wood’s lamp and KOH exam to evaluate light spots • Recommend an initial treatment plan for selected light rashes • Determine when to refer to a patient with a light rash to a dermatologist
Case One Heather Doyle
Case One: History • HPI: Heather Doyle is a 10-year-old girl who presents with several lightly colored spots on her knees and hands over the past 8 months. They do not itch. Her mother reports they have not improved with over-the-counter hydrocortisone cream. • PMH: no chronic illnesses or prior hospitalizations • Allergies: penicillin (rash) • Medications: none • Family history: grandmother with diabetes • Social history: lives at home with parents; attends elementary school; takes karate lessons • ROS: negative
Case One, Question 1 • Heather has some light colored, non-scaly, flat spots on her knees. Which of the following will likely aid in the diagnosis? • Dermatoscope • Potassium hydroxide (KOH) exam • Swab for bacterial culture • Wood’s light
Case One, Question 1 Answer: d • Heather has some light colored, non-scaly, flat spots on her knees. Which of the following will likely aid in the diagnosis? • Dermatoscope • Potassium hydroxide (KOH) exam • Swab for bacterial culture • Wood’s light
Case One, Question 2 • How would you describe Heather’s exam? • well-circumscribed hypopigmented macules and patches • well-circumscribed depigmented macules and patches • poorly circumscribed hypopigmented macules and patches • poorly circumscribed hypopigmented papules and plaques
Case One, Question 2 Answer: b • How would you describe Heather’s exam? • well-circumscribed hypopigmented macules and patches • well-circumscribed depigmented macules and patches • poorly circumscribed hypopigmented macules and patches • poorly circumscribed hypopigmented papules and plaques
Vitiligo • Lesions of vitiligo are well-circumscribed depigmentedmacules and patches. • The Wood’s light exam distinguishes hypopigmented and depigmented lesions. • Very few rashes other than vitiligo are completely depigmented.
More Examples of Vitiligo • Demonstration of bright white (depigmented) area with Wood’s light illumination
Vitiligo: The Basics • Vitiligo is caused by an autoimmune attack on melanocytes, the cells that produce skin pigment • It favors areas of trauma (knees, elbows, fingers, mouth, eyes, genitalia) • There is an association with other autoimmune disorders • Heather’s vitiligo may be autoimmune, given her family history
Vitiligo: The Basics • Treatment options include • Potent topical steroids or tacrolimus ointment • Phototherapy (Narrow band UVB, UVA) • Cosmetic cover-ups • Refer vitiligo patients to dermatology for initial evaluation
Wood’s light exam • Lighter areas without complete loss of pigment are “hypopigmented”
Steroid hypopigmentation • Skin lightening can result from potent topical or intralesional corticosteroids • The risk is higher in darker skin types. Counsel patients and parents on this risk. • Avoid this side effect by using appropriate strength topical steroids • Use high-potency steroids for short durations • Then back off to mid-potency or low-potency steroids for maintenance
Case Two Tony Maddox
Case Two: History • HPI: Tony Maddox is a 32-year-old man who presents with “blotches” on his upper back and chest for several years. They are more noticeable in the summertime. • PMH: back pain, hyperlipidemia, birthmark (Nevus of Ito) on his left chest • Allergies: none • Medications: NSAID as needed • Family history: none • Social history: aircraft mechanic • ROS: negative
Case Two, Question 1 • Mr. Maddox’s skin exam shows hypopigmented, slightly scaly macules on his upper chest. Which is the best test to confirm the diagnosis? • Bacterial culture • Direct fluorescent antibody (DFA) test • Potassium hydroxide (KOH) exam • Wood’s light
Case Two, Question 1 Answer: c • Mr. Maddox’s chest shows hypopigmented, slightly scaly macules on his upper chest. Which is the best test to confirm the diagnosis? • Bacterial culture • Direct fluorescent antibody (DFA) test • Potassium hydroxide (KOH) exam • Wood’s light
Case Two: KOH exam Spores (yeast forms) Short Hyphae The KOH exam shows short hyphae and small round spores. This is diagnostic of tinea (pityriasis) versicolor.
Diagnosis: Tinea versicolor • Based on his skin findings and KOH exam, Mr. Maddox has tinea versicolor • It’s called “versicolor” because it can be light, dark, or pink to tan • Let’s look at some examples of the various colors of tinea versicolor
Case Two, Question 2 • What is the best treatment for Mr. Maddox? • Ketoconazole shampoo • Narrow band UVB phototherapy • Oral griseofulvin • Tacrolimus cream • Triamcinolone cream
Case Two, Question 2 Answer: a • What is the best treatment for Mr. Maddox? • Ketoconazole shampoo • Narrow band UVB phototherapy (may worsen appearance by increasing contrast) • Oral griseofulvin (does not work for Malassezia species) • Tacrolimus cream (does not fight yeast) • Triamcinolone cream (does not fight yeast)
Case Two, Question 3 • What is true about the treatment of tinea versicolor? • Normal pigmentation should return within a week of treatment • Oral azoles should be used in most cases • When using shampoos as body wash, leave on for ten minutes before rinsing
Case Two, Question 3 Answer: c • What is true about the treatment of tinea versicolor? • Normal pigmentation should return within a week of treatment (usually takes weeks to months to return to normal) • Oral azoles should be used in most cases (mild cases can be treated with topicals) • When using shampoos as body wash, leave on for ten minutes before rinsing
Case Three Shaun Lee
Case Three: History • HPI: Shaun Lee is a 20-year-old male seen in the hospital with a worsening light colored scaling rash on his face. It has been getting worse since he stopped taking HAART for HIV. He also has painful erosions and ulcers in his mouth for 2 months and was admitted for pneumonia. • PMH: HIV, extensive molluscum contagiosum, pneumonia • Allergies: penicillin (rash) • Medications: levofloxacin • Family history: noncontributory • Social history: lives at home with parents; father does not believe he should take HIV medications • ROS: fatigue, dyspnea, fevers
Case Three, Question 1 • Shaun’s exam shows hypopigmented scaling patches on his central face, eyebrows, and hairline. KOH is negative. What is the most likely diagnosis? • Pityriasis alba • Seborrheic dermatitis • Steroid hypopigmentation • Tinea versicolor
Case Three, Question 1 Answer: b • Shaun’s exam shows hypopigmented scaling patches on his central face, eyebrows, and hairline. KOH is negative. What is the most likely diagnosis? • Pityriasis alba(no history of atopy) • Seborrheic dermatitis • Steroid hypopigmentation(not using steroids) • Tinea versicolor(wrong location)
Seborrheic dermatitis • Seborrheic dermatitis is a very common inflammatory reaction to the Malassezia (Pityrosporumovale) yeast that thrives on seborrheic (oil-producing) skin • It presents as erythematous scaling macules on the scalp, hairline, eyebrows, eyelids, central face and nasolabial folds, external auditory canals, or central chest • It can be hypopigmented, especially in darker skin types • Seborrheic dermatitis is often worse in HIV-positive individuals
Seborrheic dermatitis • Often hypopigmented in darker skin types
Seborrheic dermatitis Favors central chest. May be hypopigmented or erythematous.
Case Three, Question 2 • What is the best treatment for Shaun? • Caspofungin IV infusion • Clobetasol proprionate cream (high potency steroid) • Desonide cream (low potency steroid) • Imiquimod cream • Narrow band UVB phototherapy
Case Three, Question 2 Answer: c • What is the best treatment for Shaun? • Caspofungin IV infusion (this is a systemic antifungal for severe infections) • Clobetasol proprionate cream (would work, but too potent for use on the face) • Desonide cream (low potency steroid) • Imiquimod cream (irritating; for warts, actinic keratoses) • Narrow band UVB phototherapy (doesn’t work)
Seborrheic dermatitis treatment • Antidandruff shampoo • Ketoconazole (Nizoral), selenium sulfide, zinc pyrithione (Head & Shoulders) shampoos • Lather, leave on 10 minutes, rinse • 3-5 times weekly until under control • Low-potency topical steroid (e.g. desonide) for flares • Use BID for 1-2 weeks for flares • Can also use topical ketoconazole or ciclopirox, or topical pimecrolimus
Seborrheic dermatitis (scalp) • Severe scalp seborrheic dermatitis may need topical steroids; adjust to severity, patient ethnicity • Triamcinolone spray BID for flares • Fluocinolone in peanut oil (DermaSmooth™) • Wet scalp; leave on 8 hours then wash out • If wash hair daily, apply at night with shower cap • If not, use a little oil each morning • Clobetasol foam daily after shower if severe • Towel dry and apply directly to damp scalp
A note on postinflammatory hypopigmentation • Some patients heal with light spots from any rash • Stigma may be caused by fear of infectious diseases • Social impact can be more severe than original rash • Pigmentation may return slowly • It is important to treat rashes aggressively to avoid this if possible
Case Four Damien Gonsalves
Case Four: History • HPI: Damien Gonsalves is a 8-year-old boy who presents with light spots on his face. • PMH: had “eczema” as infant and young child • Allergies: none • Medications: none • Family history: brother with asthma, mother has seasonal allergic rhinitis • Social history: lives at home with parents; student in second grade • ROS: negative
Case Four: Question • Damien has hypopigmented patches on his cheeks bilaterally. The most likely diagnosis is: • Pityriasis alba • Seborrheic dermatitis • Tinea versicolor • Vitiligo
Case Four: Question Answer: a • Damien has hypopigmented patches on his cheeks bilaterally. The most likely diagnosis is: • Pityriasis alba (atopic history supports this) • Seborrheic dermatitis (usually more central) • Tinea versicolor (rarely occurs on the face) • Vitiligo (would be depigmented, not hypopigmented)