Dermatology Flashcards
1
Q
Bacterial Infections: usual etiology
A
- Staph Aureus/ MRSA or
- Strep Pyogenes (Group A Strep)
- less commonly: Pseudomonas, H. Influenza, Cornyebacter
2
Q
Primary Infections: examples
A
impetigo, ecythema, folliculitis, furuncles, carbuncles, cellulitis, sweat glad infections
3
Q
Impetigo: etiology
A
- Caused by Group A Strep, Staph aureus
- More common in hot climates or with poor hygiene; Contagious (close living quarters can be an issue)
4
Q
Impetigo: presentation
A
- superficial
- bullous = STAPH
- nonbullous = STREP A
5
Q
Ecthyma: etiology
A
-usually Group A Strep
6
Q
Ecthyma: presentation
A
- Thick, dry, hard crust (as large as 3 cm)
- Superficial (but deeper than impetigo)
- Commonly found : thighs or buttocks
- Starts as vesicle and»_space; vesicopustule
7
Q
Folliculitis: etiology
A
- VERY COMMON
-Usually caused by coagulase positive staph
-Other organisms include
Pseudomonas
Kiebsiella
Escherichia
Serratia marcescens
Proteus
MRSA
Fungi
8
Q
Folliculitis: presentation
A
- usually bacterial infection of hair follicle
- Red, elevated, tender pustule
- Hair in center of pustule
9
Q
Follicular Eczema: differential DX
A
-FE looks a lot like folliculitis but is allergic in nature; does not require antibiotics
10
Q
Cellulitis/ Erysipelas: definition and presentation
A
=Superficial skin infection that spreads to deeper dermis and subcutaneous fat/cellulitis/dermal lymphatics
- Caused by Group A streptococci, Staph aureus, Haemophilus influenza
- Fever, low blood pressure, tachycardia, and regional lymphadenitis may occur
11
Q
Furuncle: definition and etiology
A
= spread of acute Staph infection from hair follicle to adjacent dermis
-caused by Staph and MRSA
12
Q
Furuncle: presentation
A
-painful nodule with pustular center
13
Q
What is a secondary infection?
A
=complication of pre-existing skin disorder
14
Q
Examples of secondary infections=
A
Staph aureus Methicillin-resistant Staph aureus Streptococci Enterococci Enterobacteriaceae Anaerobes
15
Q
Nonpharmalogical TX for bacterial skin infections:
A
- Clean the area
- Bacteriocidal soap/chlorhexadine
- Bleach baths
- Warm compresses to furuncles
- Incision and drainage
- Culture
16
Q
Topical TX of bacterial skin infections:
A
- Bacitracin (not preferred)
- Bactroban: BID x 5-10 d
- Altabax 1%: BID x 5 d (only 9 mo +)
17
Q
Topical TX options for folliculitis:
A
- Clindamycin: topical BID
- Erythromycin: topical BID
- Bactroban: topical BID
18
Q
Simple skin infections: 1st line oral antibiotics
A
-Amoxicillin/clavulinic acid: 25–50 mg/kg/day divided BID
-Cephalexin: 25–50 mg/kg/day divided TID, max 500 mg TID
Cannot be used for MRSA
-Dicloxacillin: 250–500 mg QID × 5–7 days
19
Q
Pseudomonal Infections- TX:
A
- If unsure whether infection is pseudomonas, can start with the previous agents, but may need to change to Cipro
- If pseudomonas: start with Ciproflaxin: 500 mg BID × 7–14 days
- Other options: beta lactam and a macrolide
20
Q
Skin infections: second-line oral antibiotics
A
- Note: If the patient has multiples allergies, look up second-line oral antibiotics on a case-by-case basis.
- Azithromycin: 500 mg po on first day, then 250 mg po qd × 4 days
- Erythromycin: 250–500 mg po (adult) × 5–7 days
- Clindamycin: 15 mg/kg/day po TID × 10 days
21
Q
MRSA: oral antibiotics
A
- Clindamycin: 30–40 mg/kg/day max 450 mg po TID
- Bactrim: 4–6 mg/kg/dose of TMP max 2 DS tabs BID
- Doxycycline: 100 mg po BID
- Minocycline: 200 mg po × 1, then 100 mg po BID
- Linezolid: 600 mg po BID
22
Q
Inpatient RX for MRSA:
A
- Vancomycin IV
- Daptomycin IV
- Linezolid po/IV
- Telavancin IV
- Clindamycin po/IV
- Tigecycline
- Ceftaroline
23
Q
What is decolonization? When is it used, how done?
A
- Patients with persistent staph, strep, or MRSA infections (and even household contacts, on a case-by-case basis) may be considered for decolonization.
- Mupirocin nasal: apply to nares BID × 5–10 days
- Chlorhexadine: apply to body × 7–14 days
- Bleach baths
24
Q
Decolonization: Bleach baths- the “how to”
A
-Bleach baths have become a common recommendation and come in various forms:
-Spray on
-Tub
IDSA 2011 Treatment
For diluted bleach baths, use 1 teaspoon per gallon of water (or 1/4 cup per 1/4 tub, or 13 gallons of water), for 15 minutes twice a week for about 3 months.
25
Acne: prevalence
- 85% of population (12-25 yo)
- more severe/ frequent in males
- can occur in neonates related to maternal androgen exposure
26
Acne: definition
- Acne is a disorder of the pilosebaceous unit of the skin
- inflammatory or noninflammatory
- Usually inflammatory by the time of primary care consultation
27
Acne: development
1. Comedo (dried sebum and keratin) plugs a pore, creating a "whitehead"
2 .Oxidation of melanin and sebum in the plugs creates open comedones
3. Proliferation of Propionibacterium acnes creates inflammation, inciting formation of erythematous papules
4. Inflammation progresses, forming pustules
5. Pustules can become cystic due to abscess formation, and scarring may occur (at this point the patient should see a doctor)
28
Acne: nonpharmacologic TX
Patients should:
1. Gently wash face twice a day using mild soap
2. Avoid oil-based skin care, cosmetics, and hair care products
3. If using oil-based ethnic hair care products, follow up by washing off skin along hairline
4. Avoid friction or scrubbing
29
Acne: PCP review and Pt ed-
As a dermatologist, you should
1. Review full current regimen for both skin and hair
2. Review what you will do for the patient
3. Explain that it usually takes up to three medications to find the right option
4. Provide drug education (e.g., skin usually gets worse before it gets better)
30
Pharmacologic TX for Acne:
1. Keratolytics
Antibacterial action
Reduce hyperkeratinization
2. Retinoids
Reverse abnormal keratinization
3. Antibiotics
Reduce microbial colonization and decrease inflammatory response
Used best when in combination with keratolytic or retinoid
If used alone, bacterial resistance can occur
31
Keratolytics: examples
- Benzoyl Peroxide
- Salicylic Acid
- Azelaic Acid
- Sulfur (has odor; rare)
32
Benzoyl Peroxide: options/ notable
- OTC or Rx
- Forms: wash, soap, lotion, gel, solution
- Can cause irritation or scaling
- May bleach clothing or hair (rare)
- No bacterial resistance
33
Retinoids: 3 options/ notable
-Tretinoin (Retin-A)
Forms: cream, gel, solution
May cause local irritation, but this usually improves with time
Tumorigenic in animals with UV light, so must always use sunscreen!
-Adapalene (Differin) 0.1%
Works well, comparatively, with less irritation
-Tazarotene (Tazorac)
Forms: 0.1% gel and cream
Should not be used during pregnancy
Women who use it should be on contraception
34
Topical Antibiotics: options/ notable
- Available in gel, solution, or lotion
- Must be used in combination with benzoyl peroxide to decrease keratinization and bacterial drug resistance
- As insurance companies do not usually cover the combination medications that include benzoyl peroxide, these antibiotics require drug education to ensure the patient knows to use both together
35
Topical Antibiotics: name 3
Types
- Erythromycin
- Clindamycin
- Sulfacetamide
36
TX of severe acne in primary care-
In cases of severe acne, the patient should be sent to dermatology, but the following options are available in primary care:
- Tetracycline: 250 mg QID
- Doxycycline: 100 mg BID
- Minocycline: 50–100 mg QD-BID
37
Accutane (Isoretinoin) : Indications and who can RX
- Accutane must be prescribed by a dermatologist registered through the I-PLEDGE program
- Only for severe cystic acne and may have some harsh side effects
38
Accutane: SE's and pt monitoring
- Dryness, itching of mucous membranes and skin, and premature closure of epiphyses
- When using, patients must undergo:
1. regular pregnancy tests and
2. monitor their lipids, also
3. monitor the patient for depression
4. and osteoporosis
39
Stepwise care for acne
1. Nonpharmalogical care
2. Topical keratolytic
3. Topical retinoid (alone) at PM
4. Topical antibiotic
5. Systemic antibiotic
6. Systemic isotretinoin (Accutane)
40
Scabies: presentation
- Look for dermatitis that is worse on trunk, hands, feet, and perineum
- May have burrows
41
Scabies: TX (and SEs, pregnancy category)
-Elimite cream:
Sleep with cream on, then shower it off in the morning and wash clothing and bedding in HOT water
-Topical antiparasitic/pediculocide/scabicidal
-Pregnancy Factor B
-Lactation safety: unknown
-Side effects: pruritis, erythema, rash, and edema
42
Flea or mosquito bites: presentation and TX
-Characterized by punctate papules
-Many patients have hypersensitivity reactions
There is widespread id reaction or papular urticaria
-Treat with Benadryl, topical Benadryl, or calamine
-If those fail, steroid creams can be used.
43
Pediculosis: presentation
- Found on the head, body, or pubis
| - Erythema and scaling may be present
44
Pediculosis: notable
- Very contagious and highly resistant to medication
| - Patients should take great care to avoid recurrence
45
Pediculosis: TX
1. Pyrethrins or permethrin (OTC)
2. Malathion (RX): Ovide
-For those ages 6 and older
-Inhibits cholinesterase
Apply to dry hair/scalp and leave on for 8–12 hours
Do not use with infants or neonates
3. Ivermectin topical and spinosad (RX): both are ovicidal
4. Lindane (RX): not first line and cannot be used with children less than 2 years of age or those with seizures
46
Pediculosis TX: NONNEUROTOXIC TX
-Benzyl alcohol lotion 5% (Ulesfia)
-4% dimeticone lotion (not occlusive)
-Other occlusives: olive oil, vaseline, mayonnaise
[Benzoyl alcohol is FDA approved, dimeticone has one study
Others have no evidence base]
47
Atopic Dermatitis: presentation/ cardinal SX
- Can be intrinsic or extrinsic
- Characterized by acute erythema, scaling, fissuring, and may have vesicles or papules
- Called "the itch that rashes" (if it does not itch, it is not atopic dermatitis)
- Chronic signs and symptoms develop into lichenification of skin
48
Atopic Dermatitis: TX
-Medical treatment is primarily: topical corticosteroids
-Can try nonpharmacologic treatments at first
Avoidance of perfumes, irritants such as smoke, laundry detergent, soaps, and bubble bath
Decrease in frequency of bathing, temperature of bath water, and duration of shower/bath
Wearing loose/cotton clothing (avoid synthetic fibers and wool)
49
Atopic Dermatitis: notable-
Note: Evidence shows that a large number of people with AD also have a metal allergy. Make sure to exclude all metal, and cover with nail polish. Otherwise, the treatment may not work.
50
Atopic Dermatitis: first line TX
First Line: Emollients
- Steroid sparing
- Minimum or BID application and after bathing
- Ideal moisturizer is thick, as well as fragrance and alcohol free
51
Atopic Dermatitis: second line TX
TOPICAL CORTICOSTEROIDS
=Mainstay of pharmacologic treatment
Anti-inflammatory
52
Topical Corticosteroids- Classes/ how rated
Rated by vasoconstrictor effect (most potent: Class 1; least potent: Class 7)
53
Topical Corticosteroids: duration of action potency/ absorption
- Longer duration of use and higher potency steroid increases risk of side effects
- Absorption is influenced by surface area used, thickness of the skin, vehicle type, drug concentration, and use of occlusive dressings (or not)
54
Topical Corticosteroids- RULES OF THUMB
* No Class 1–5 topical steroids should touch eyelids, face, mucous membranes, genitalia, intertriginous areas
* Potent topical steroids may be needed on the palms and soles
* The younger the child, the lower the potency
55
Atopic Dermatitis: example-
| 3-month-old infant with papules and xerosis on face
3-month-old infant with papules and xerosis on face
-Start with 0.5% hydrocortisone cream
-Always use 0.5% or 1% HCT on young infants, unless severe
Example 2: 36-year-old with lichenification of popliteal and antecubital space
Use an ointment like Triamcinalone 0.025%, and move up higher if needed
56
Atopic Dermatitis: example-
| 36-year-old with lichenification of popliteal and antecubital space
36-year-old with lichenification of popliteal and antecubital space
-Use an ointment like Triamcinalone 0.025%, and move up higher if needed
57
Choices of "vehicles" for topical steroids
* Use a low-potency topical steroid for maintenance and higher potency steroids for acute exacerbations (e.g., an oral steroid "burst")
- Ointments: more potent and penetrate stratum corneum better
- Foams and loations: less messy for hairy areas
- Creams
58
Topical Steroids: SEs
- HPA access suppression
- Systemic absorption
- Skin atrophy, corticoid rosacea
- Steroid-induced acne
- Hypopigmentation
- Hypertrichosis
- Increased intraocular pressure
- Cataracts
- Contact dermatitis
59
Calcineurin Inhibitors: uses, benefits
- May be used with steroids or as an alternative to topical steroids
- No steroid side effects, so can be used in areas of thinner epidermis
- Use only for the short term, second line, and not for those younger than 2 years of age
60
Calcineurin Inhibitors: SEs and Adv Effects
- burning sensation possible
- Adverse effects: viral infections, HSV, molluscum, varicella, warts
- Side effects: flu-like symptoms, allergic reactions, asthma, coughing, fever, AOM, headache
61
Calcineurin Inhibitors: FDA warning
Warning from FDA in 2005: use increases risk of skin cancer and lymphoma
62
Calcineurin Inhibitors: 2 RX options
1. Pimecrolimus (Elidel): use for ages 2 and older
2. Tacrolimus (Protopic):
Ages 2–15: .03% ung
Ages 16 and older: 0.1% tacrolimus ung
63
Calcineurin Inhibitors: MOA
Inhibits phosphatase activity of calcineurin: results in inhibition of T-cell activation
64
Atopic Dermatits: systemic TX options
1. Oral antihistamines
2. Oral steroids: rebound
3. Immunomodulators
4. Phototherapy
5. Antimicrobials
65
Seborrheic Dermatitis: presentation / occurrence
- Characterized by diffuse papular rash that can develop into greasy, crusty, scaly lesions
- -Ranges from nonpruitic (in infants) to very pruritic
- When on the scalp, often accompanied by hair loss (alopecia)
- Most frequently occurs in the first year of life, but can occur again in adolescence and adulthood
- More common in men
66
Seborrheic Dermatitis: etiology
-Malassezia furfur has been implicated as a causative agent in older onset seborrhea (unclear whether this is consistent for infantile seborrhea)
67
Seborrheic Dermatitis: TX
- There is no FDA-approved treatment for those under 2 years old.
- Pharmacologic therapy works best if wet compresses are applied before application of medication.
- OTC solutions: daily use of antiseborrheic shampoo containing selenium sulfide, sulfur, salicylic acid, zinc pyrithione, tar
- Topical corticosteroids (ketoconazole to treat Malassezia furfur)
- Topical immunomodulators if older than 2 years old
68
Psoriasis: presentation / SX
=Skin disorder caused by uncontrolled accelerated replication of the basal epidermal cells
- Causes redness, flaking, and thickened patches (plaques)
- Frequently has exacerbations and remissions
69
Psoriasis: precipitated by-
Precipitated by
- Infection
- Skin trauma
- Medications (lithium, antimalarials, beta-blockers, etc.)
- Sunlight: improves or worsens
- Stress and/or emotional upset
- Alcohol and smoking
- Hormonal changes
70
Psoriasis: categorizations
- Plaque psoriasis
- Guttate psoriasis
- Palmo-plantar psoriasis
- Generalized pustular psoriasis
- Flexural psoriasis
- Erythrodermic psoriasis
- Scalp psoriasis
- Nail psoriasis
71
Psoriasis: TX (pharm and nonpharm)
NONPHARM:
-Emollients (for bath or shower): soap, moisturizers
-Tar or keratolytic shampoos (selenium, ketoconazole, anthralin, salicylic acid)
-Tar and UV light
-Keratolytic agents (to plaques): sulfur, salicylic acid
-Vitamin D: calcitrol for those 12 years and older
PHARM RX:
-Topical steroids
-Anthralin ung (to plaques)
-Tazarotene: retinoid
72
Psoriasis: systemic TX monitoring
-All systemic agents for psoriasis require monthly liver function tests (LFTs) and specialty management
73
Psoriasis: systemic TX options
- Methotrexate
- Cyclosporine
- Acitretin
- Azathioprine
- Fumaric acid esters
- Hydroxyurea
- Leflunomide
- Mycophenolate mofetil
- Sulfasalazine
- Tacrolimus
- 6 thioguanine
74
Polyene Antifungals: MOA and 2 options
- Bind to sterols in the cell membrane of the fungus, causing increased membrane permeability and loss of intracellular contents
- Examples:
1. Amphotericin B
2. Nystatin
75
Amphotericin B (polyene antifungal): MOA, preparation, absorption, protein binding
-One of the earliest effective antifungals available systemically (Also comes in topical formulation)
-Selective fungicidal: binds to ergosterol in fungi cell wall
>>Causes leakage of intracellular ions and macromolecules, leading to cell death
**High toxicity [Can also bind to human membrane sterols (possible cause for toxicity)]
= An amphoteric polyene macrolide
= Insoluble in water, so needs to be a colloidal suspension
-Poorly absorbed from the GI tract: only effective PO for infections of GI tract
-90% protein bound
76
Amphotericin B (polyene antifungal): T 1/2
-Has a very long half-life: slow excretion (15 days)
77
Amphotericin B (polyene antifungal): spectrum of action against these fungi
```
Broad spectrum of action
Effective against
Candida
Cryptococcus
Histoplasma capsulatum
Blastomyces dermatidis
Coccidiodes
Aspergillus
```
78
Amphotericin B (polyene antifungal): Uses
Being highly effective, may be used initially for serious fungal infection (then switched to an azole)
Topical uses: corneal ulcers, keratitis, joints, bladder irrigation
Also for paronychia, intertrigo (yeast)
79
Amphotericin B (polyene antifungal): SEs (systemic and topical)
- Side effects (topical): yellow staining, mild irritation
- Side effects (systemic): fever, chills, muscle spasm, vomiting, headache, hypotension
- Over time, leads to renal damage
80
Nystatin: Polyene antifungal- Preparations, Uses
= Polyene macrolide
- Too toxic for parenteral use but widely used topically
- Available in cream, ointment, suppositories, oral suspension
- Not absorbed to any significant degree through GI tract, skin, or MM
- Active against Candida: oropharyngeal, vaginal, intertriginous, paronynchia
81
Nystatin: Polyene antifungal- SEs
```
Side effects (oral): bad taste, mild nausea, diarrhea, vomiting
-No or limited topical irritation or hypersensitivity reactions
```
82
TRIAZOLE antifungals: MOA
- Reduce ergosterol synthesis by inhibition of fungal cytochrome P450
- Less active against human cyt P450 than fungal cyt P450
83
TRIAZOLE antifungals: examples
Examples:
- Fluconazole
- Itraconazole
- Posoconazole
- Voriconazole
84
IMIDAZOLE antifungals: MOA
Same mechanism of action, but less selective to fungal vs. human cells so more problematic if given orally
85
IMIDAZOLE antifungals: examples
Examples
- Butoconazole
- Clotrimazole
- Ketoconazole
- Econazole
- Miconazole
- Oxiconazole
- Sulconazole
- Terconazole
- Tioconazole
86
AZOLE antifungals: spectrum of action
```
All display broad activity including
Candida
C. neoformans
Blastomycosis
Coccidioidomycosis
Histoplasmosis
Dermatophytes
```
87
AZOLE antifungals: SEs and interactions
Side effects: minor GI upset (common)
Can cause drug-induced hepatitis, elevated liver enzymes
Major cyt P450 interactions
88
AZOLE antifungals: most commonly used in clinical practice
Most commonly used in clinical practice
- Topical ketoconazole
- PO itraconazole
- PO fluconazole
- Topical clotrimazole, miconazole, econazole
89
Ketoconazole (Nizoral): type of antifungal
=Imidazole antifungal
Earliest drug in its class
Greater propensity to inhibit CYP450 enzymes than newer azoles when given systemically
90
Ketoconazole (Nizoral): typcial uses
-Systemic use has fallen out of favor due to side effect profile (hepatotoxicity, nausea/vomiting)
-Topical use common: available as shampoo, cream
=Used primarily for tinea versicolor, but also for seborrhea
-The shampoo can be used to decrease shedding of tinea capitis
91
Ketoconazole (Nizoral): effective against-
Effective against:
- Epidermophyton
- Microsporum
- Tricophyton
92
Ketoconazole (Nizoral): systemic TX
Systemic treatment:
- Glabrous skin responds in 2 to 3 weeks
- Palmar-plantar skin slowest to respond
- Hair and nails longer, low cure rate with tinea capitis
93
Ketoconazole (Nizoral): topical SEs
Side effects (topical): increased hair loss, skin irritation, change in hair texture, pruritis and dry skin
Contraindication: hypersensitivity
Precautions: liver disease, achlorhydria or hypochlorydria, alcohol abuse
94
Ketoconazole (Nizoral): systemic SEs
```
Side effects (systemic): nausea, pruritis, gynecomastia
May increase AST, ALT, alkaline phosphate, bilirubin, drug-induced hepatitis risk
```
95
Ketoconazole (Nizoral): notables- odor, cost
- Less concern regarding odor than selenium shampoo (also used for tinea)
- Increased cost
96
Allylamine antifungals: MOA
=Inhibit the synthesis of ergosterol by inhibiting squalene epoxidase
97
Allylamine antifungals: examples
Examples
Butenafine (Mentex)
Naftifine (Naftin)
Terbinafine (Lamisil)
98
Terbinafine (Lamisil): MOA and effective against...
-Inhibits epoxidation of squalene in fungi, so is toxic to fungi
-Also reduces ergosterol and prevents synthesis of fungal cell membrane
Highly effective against dermatophytes but less effective against yeast
99
Terbinafine (Lamisil): SEs (topical and systemic)
- Side effects (topical): local irritation, burning, erythema
- Side effects (systemic): monitor closely for hepatic dysfunction
100
Glucan Synthesis Inhibitors- examples
Not used in primary care!
- Caspofungin
- Mycafungin
- Anidulafungin
101
Griseofulvin (misc. antifungal): preferred agent for; preparations available
=Preferred agent for tinea capitis, and for tinea corporis if oral treatment needed
-Microsize vs. ultramicrosize (be careful!)
Microsize 10–20 mg/kg/day
Ultramicrosize 5–10 mg/kg/day
-Easiest for patients to find in liquid form
102
Griseofulvin (misc. antifungal): MOA, absorption (how best absorbed); interactions
- Inhibits fungal cell mitosis at metaphase by interfering with cells mitotic spindle structure
- Cytochrome P450 isoenzyme CYP1A2 inducer
- Has increased absorption with simultaneous ingestion of fatty foods
103
Griseofulvin (misc. antifungal): Pt teaching and monitoring
- Teach your patients to take with dinner and with butter, gravy, whole milk, or ice cream
- Can cause hepatotoxicity, so mandates close follow-up
- Some will draw LFTs at baseline
- Most recommend LFTs after 1 to 2 months of therapy
104
Tolnaftate (Tinactin): uses, SEs, preparations available
- Available OTC
- Works well on dermatophytes
- May cause some local skin irritation
- Dosed BID as cream
- May be used for prevention of reinfection (OTC powders and spray)
105
Ciclopirox (Pen-Lac, Loprox) : MOA
- Acts by chelating polyvalent cations (Fe+3) or (Al+3)
| - Inhibits enzymes responsible for the breakdown of peroxidises within fungal cells
106
Ciclopirox (Pen-Lac, Loprox): uses
=Alternative to systemic treatment for onychomycosis
| -Also can be used for other dermatomycosese, candidiasis, tinea versicolor (lotion)
107
Ciclopirox (Pen-Lac, Loprox): How to use in Onychomyosis
-Onychomysosis
Apply 8% solution over entire nail plate once daily
Make daily applications over previous coats
Remove with alcohol every 7 days
Nails may need to be filed down so drug can work
108
Ciclopirox (Pen-Lac, Loprox): Do not use with...
Should not be used together with systemic antifungals
| This is controversial in the literature
109
Selenium Sulfide Shampoo (Selsun): MOA, uses; strengths
-Mechanism of action unknown but may block enzymes involved in growth of epithelial tissue
-Controls but does not cure fungal infections of the scalp and skin
-Also used for seborrhea and psoriasis
2.5% prescription strength
1% available widely OTC
110
Selenium Sulfide Shampoo (Selsun): SEs, age limit
- Has an odor: an issue for some patients
- May also cause discoloration or alopecia
- Questionable to use for
111
Fungal infections- how to DX
=Diagnosis by clinical characteristics and, if needed, KOH and/or culture
112
Mycoses: definition and examples
- Mycoses: fungal infections where the fungus has bypassed the body's first line of defense
- Examples: vaginal candidiasis, tinea pedis, onychomycosis, many more
113
Dermatophytes: examples of DX's and organisms
-Tinea pedis, or "athlete's foot" (see image)
-Tinea manus: tinea of hands
-Onychomycosis: fungus of nails
-Tinea cruris, or "jock itch"
-Tinea corporis: ringworm of skin
Organisms include:
-Epidermophyton
-Microsporum
-Trichophyton
114
Tinea Pedis: TX
```
Tinea pedis (all good choices):
Tinactin, Lotrimin, econazole
```
115
Tinea Manum: TX
Tinea manum:
| Imadazoles, allymaines, tolnaftate
116
Tinea corporis: TX
```
Tinea corporis (see image):
Imidazoles, allylamines, tolnaftate
```
117
The "Tineas" - systemic TX
If systemic therapy needed: griseofulvin, itraconazole, terbinafine, Diflucan
118
Tinea Versicolor: etiology, presentation
=Caused by Malassezia furfur (new name)
- Scaly oval macules that can coalesce
- Can be white, red, or brown, hyperpigmented, or hypopigmented
- Most commonly found on the trunk, upper arms, neck
- Normal part of skin flora but can proliferate if in warm/humid environment or immunosuppressed
- Also due to genetic factors
119
Tinea Versicolor: TX
-Can use any azole, but ketoconazole particularly effective
120
Onychomosis: common presentation; organisms
- More common on toenails
- Caused by Trichophyton rubrum and Trichophyton mentagrophytes
- Can be caused by candida (more common in fingernails)
121
Onychomosis: TX and RISK
- Oral treatment most effective: Lamisil (terbinafine), itraconazole
- Possible alternatives, not FDA approved: fluconazole, pozaconazole
- Difficult to get insurance to cover
* *Significant risk of liver toxicity
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Tinea Capitis: presentation
- Noninflammatory and inflammatory
- Can be gray or white and scaly, broken hairs, or alopecia
- Round pustular scaly patches
- Can be in knots
- Local lymphadenopathy common
123
Tinea Capitis: TX and monitoring
* Must be treated orally
* Requires minimum of one month of treatment due to drug resistance
* Requires monitoring of liver enzymes, especially in adults
- If severe hair loss/inflammation, may use oral steroids as well
124
What is Tinea Capitis + inflammation called?
Kerion
125
Tinea Capitis: TX options-
- Griseofulvin
- Ketoconazole
- Fluconazole
- Itraconazole
126
Yeast Infections: organisms
-Candida albicans: causative agent of oral, vaginal, skin, nails, lungs, and GI infections
-Part of normal flora
-Other Candida tropicalis and glabrata
Pityrosporum (Malassezia) indicated as well
-Can develop yeast folliculitis as well
127
Candida: TX of oral, diaper/ skin, and vaginal
- Oral: Nystatin suspension or Mycelex troches
- Diaper rash, other candidal skin rashes: best with Nystatin ointment or cream
- Vaginal yeast infections: imidazole antifungals all effective
- Miconazole is least expensive and OTC
- If severe, may use oral fluconazole
128
Antivirals: Nucleoside Analogues- examples and MOA
- Acyclovir
- Valacyclovir
- Famciclovir
- Penciclovir
- Ganciclovir: used to treat CMV
- Ribavirin: active against many viruses but less frequently used
- These inhibit viral DNA synthesis.
129
ACYCLOVIR Family anitvirals: MOA, efficacy, SE
-Similar in efficacy and s/e panels
-Inhibits DNA synthesis and viral replication
-Competes with deoxyguanosine triphosphate binding DNA templates into irreversible complexes
-Causes chain termination following incorporation of viral DNA
=Side effects: many, but hydration to prevent nephrotoxicity most important
130
ACYCLOVIR Family anitvirals: major issues and pt monitoring
- Major issues in choice: cost and frequency of dosing
| - Also monitor cbc if long course
131
Acyclovir effective against:
- Active against HSV-1, HSV-2, and varicella
- Much more against HSV than VZV
- [Weak in vitro activity against Epstein-Barr, cytomegalovirus, and human herpes virus-6 (HHV-6)]
132
Acyclovir: activation, absorption (with food?) and topical prep
- Requires three phosphorylation steps for activation
- Low bioavailability after oral absorption
- Unaffected by food
- As topical formulation, has high concentrations at lesion sites
133
Acyclovir: clearance/ T 1/2
Cleared primarily by glomerular filtration and tubular secretion
Very long half-life if these processes are compromised
134
Acyclovir: diffuses into CSF? Resistance?
Diffuses well: 20–50% into CSF
Can result in HSV and VZV becoming resistant, especially in immunocompromised hosts
Cross resistance to valacyclovir, famiciclovir, ganciclovir
135
Acyclovir: SEs, risks of toxicity; how to prevent toxicity
Side effects (most common): nausea, diarrhea, headache
IV particularly associated with renal toxicity and neurologic effects (some drugs increase this)
Preventable for the most part with hydration and slow administration
136
Valacyclovir: how related to Acyclovir/ how activated/ effective for-
L-valyl ester of acyclovir
Converted by body to acyclovir after oral administration via first pass
Levels are 3–5× that of oral acyclovir
Oral bioavailability of 54–70% (CSF is 50% of serum)
Effective for HSV infections, varicella, varicella zoster
Can be used in high dose for CMV prophylaxis
137
Valacyclovir: SEs and risks
Side effects: nausea, headache, vomiting, rash
Side effects (at high doses): confusion, hallucinations, seizures
Also increased risk of thrombocytopenic purpura, hemolytic uremic syndrome
138
Famciclovir: effective against
- Active against HSV, VZV, EBV, and HBV
| - Less affinity than acyclovir for viral DNA but higher intracellular concentration
139
Famciclovir: SEs
- Side effects: headache, nausea, diarrhea
| - Acyclovir and famciclovir can cause testicular toxicity in animals, but in not humans
140
Ganciclovir: effective against-
- Effective against CMV: used most often post organ transplant or in HIV-infected patients
- Activated in CMV infected cells
- In vitro activity also against HSV, VZV, EBV, HHV-6, and HHV-8
141
Ganciclovir: preps, resistance?
Can be given IV, orally, or intraocularly
| Results in resistance, especially with longer courses of treatment
142
Ganciclovir: SEs and toxicity?
-Side effects: myelosuppression
Nausea, diarrhea, fever, rash, headache, insomnia, peripheral neuropathy
-CNS toxicity and hepatotoxicity (less common)
-Mutagenic and carcinogenic, embryotoxic in animals
143
Miscellaneous Meds for Viral Infections:
- Salicylic acid: nongenital warts
- Imiquimod: warts or molluscum
- Cantharidin (blister beetle)
- Cryotherapy
- Cimetidine oral: for warts
- Retinoic acid: flat warts
- Podophyllin 25%: genital warts
- TCA
144
Salicylic Acid: use and MOA
- Extensively used as a keratolytic
- Solubilizes cell surface proteins in stratum corneum
- Possible desquamation
145
Salicylic Acid: % used; absorption; concerns in certain populations/ allergy
-3–6% keratolytic, >6% more destructive
Requires that you be wary of absorption
Salicylic acid levels of 30–50% are toxic
A concern in children
Allergy to salicylates: urticaria, anaphylaxis, erythema multiforme
146
Salicylic Acid: SEs and caution in pts with _____ and _____
- Side effects: local irritation, acute inflammation, ulceration
- Caution with diabetics and peripheral vascular disease
147
Imiquimod: MOA
- Immune response modifier
- Mechanism of action unknown
- Possibly stimulates mononuclear cells to release interferon alpha and to stimluate macrophages to produce interleukins 1, 6, 8, and TNF alpha
148
Imiquimod: how administered
-Widely used for genital warts, verucca vulgaris, actinic keratosis, molluscum
-Administered topically 2–5 times/week depending on pathology
5% cream for warts, actinic keratosis, basal cell carcinoma
3.75% for face and scalp actinic keratosis
149
Imiquimod: SEs
Side effects: local inflammatory reactions, pruritis, erythema, erosion, flu-like symptoms
150
Podophyllum Resin: uses, MOA, absorption
-Same as mandrake root or Mayapple
-Used in the treatment of condyloma acculumlata or veruccae in general
-Office-applied solution: a mix of podophyllotoxin and many similar compounds in alcohol or benzoin
Can be absorbed and once absorbed distributes widely
Mechanism of action
Cytotoxic with an affinity for the microtubule of the mitotic spindle
Interrupts in metaphase
As 25% solution, to be applied to wart tissue only!
Should have limited application area to avoid systemic absorption
Side effects with normal use: local irritation, severe conjunctivitis if contact with eye
Cytotoxic to embryo in pregnancy (Do not use!)
Signs of toxicity: nausea, vomiting, alterations in sensorium, muscle weakness, neuropathy, coma, death
151
Podophyllum Resin: % solution, how to avoid absorption
- As 25% solution, to be applied to wart tissue only!
| - Should have limited application area to avoid systemic absorption
152
Podophyllum Resin: SEs, USE IN PREG?, signs of toxicity
- Side effects with normal use: local irritation, severe conjunctivitis if contact with eye
- Cytotoxic to embryo in pregnancy (Do not use!)
- Signs of toxicity: nausea, vomiting, alterations in sensorium, muscle weakness, neuropathy, coma, death
153
Podofilox: preparations and indications; administration
- Solution or gel (0.5%) can by applied by patient
- Indicated for genital condylomas
- Low concentration: reduces the potential of toxicity
- Self-administered at BID dosing (2×/day) for 3 days, then 4 days break
154
Podofilox: SEs
Side effects: inflammation, erosions, burning, itching
155
Anti-Influenza Medications:
1) Neuraminidase inhibitors
- Oseltamir
- Zanamivir
2) M2 protein inhibitors
- Amantadine
- Rimantadine
156
Anti-Influenza Meds: general guidelines
- Guidelines change every year: check CDC each year
- With appropriate use, can shorten the course of illness, decrease viral shedding, and prevent complications
- Recommended to start within 48 hours of beginning of illness
157
Anti-INfluenza Meds: age limitations, contraindications; resistance, elder dosing
-Oseltamivir preferred for peds
158
Who should be treated for Influenza?
-Peds
159
Viral Skin Infections:
```
-Herpes simplex virus
Gingivostomatitis
Herpes labialis
Herpetic whitlow
Skin infections
Neonatal herpes
Genital herpes
-Viral skin warts
-Herpes zoster and varicella
-Molluscum contagiosum
```
160
Gingivostomatitis: TX
-Generally treatment just for comfort
Tylenol
-Avoidance of acidic or spicy foods
-Swish and spit Benadryl: Kaopectate (????) 1:1 solution (dose by weight if swallowed)
-Lidocaine generally not used outpatient, but may be inpatient
-If severe (i.e., not taking POs, high fever), may treat with oral acyclovir
161
Herpes Labialis: prevention, OTC TX and RX TX
-prevention with sunscreen, chapstick, avoiding cracks in lips
-May use OTC treatment: fair effectiveness
Abreva
Carmex
-Acyclovir ointment (though more and more insurances not covering)
-Oral acyclovir if severe
162
Skin Infections with HSV: primary and secondary TX
-Primary infection: treatment optional if well appearing
-Secondary infection (e.g., eczema herpeticum)
May need to be admitted for IV acyclovir, some outpatient management
Be very careful: need systemic treatment and consult
163
Neonatal Herpes: incubation, TX
- Incubation period is 2–4 weeks of age but systemic diseases can develop much later
- Must have high index of suspicion in all neonates
- Must be admitted for IV acyclovir (to prevent devastating systemic diseases)
164
Genital Herpes: TX
```
-Can be treated with
Oral acyclovir: 3–5 times/day
Famciclovir TID
Valacyclovir BID
-To decide what regimen consider
Cost
Frequency of dosing
Is this the initial infection? Recurrent infection? Prophylaxis?
```
165
Viral Warts: types/ etiology
- Caused by HPV virus: 150+ subtypes
- Verrucae vulgaris
- Flat warts
- Plantar warts
- Genital warts
166
Viral Warts: TX
- All miscellaneous agents
- Cryotherapy
- Tape: duct tape or scotch tape
- Imiquimod
- TCA
- Podophyllin
- Oral cimetidine
167
Molluscum Contagiosum: presentation, how spread
- Very common in kids, spread by self-inoculation
- May also be seen as STI, or as superinfection of eczema
- Dome-shaped lesions that may become umbilicated
168
Molluscum Contagiosum: TX
```
*Treatment may be worse than no treatment
Treatment:
-Cantharidin (dermatology)
-Imiquod (best but expensive)
-Oral cimetidine (children)
-Tretinoin
-Curettage
-Cryotherapy
-Podophyllotoxin, TCA, salicylic acid can be used in office
```
