Cutaneous Fungal Infections

Question 1

What are the two common type of cutaneous fungal infections?

Answer 1

Dermatophytes
Yeast

Question 2

What are 3 types of dermatophytes fungal infections?
(dermatophytes are NOT on mucosal tissue)

-tinea affects upper layer, dermatophytes eat dead keratin cell layer

Answer 2

tinea corporis - ringworm of the body
(no actual worm involved)
tinea cruris - jock itch
tinea pedis - athletes foot

Question 3

What are two types of yeast fungal infections?
(these might occur on mucosal layers)

Answer 3

cutaneous candidiasis - occurs in intertriginous areas-groin, axillae, interdigital spaces, under the breast
pityriasis versicolor (malazzezia)

Question 4

what are 5 goals of therapy

Answer 4

1. eradicate existing infection - inhibit fungal growth (cure the infection)
2. provide symptomatic relief (itching, burning and other discomforts)
3. stop infection from spreading
4. stop complications (such as secondary bacterial infection)
5. avoid recurrences

Question 5

What are 4 non prescription treatments?

Answer 5

clotrimazole 1% or miconazole 2%
tolnaftate 1%
undecylenic acid
nystatin 100 000 units/g

Question 6

NON P - Clotrimazole 1% (canesten + generics) or Miconazole 2% (micatin + generics)
classification
mechanism of action
effective in treatment of ____ and ____
adverse effects:
nonprescription preparations currently available in Canada
Cure rate?

Answer 6

C: Azoles
Mech of action: Fungistatic, concentration may lead to fungicidal effects and blocks production of ergosterol, triglycerides and phospholipids by fungi
-broad spectrum
AE = local skin irritation, (erythema, pruritus, rash, stinging, and rarely hypersensitivity)
NonP: clotrimazole 1% (canesten + generics) cream
NonP: Miconazole nitrate 2% (micatin+generics) cream, spray, powder
cure rate = 80-90%
fast onset of action, 1-2 weeks but can stop the itch in 1-2 days

Question 7

NON P - Tolnaftate 1% (Tinactin + generics)
classification
mechanism of action
effective in treatment of ____ and ____
adverse effects:
nonprescription preparations currently available in Canada

Answer 7

C: thiocarbamate
Mech of action: narrow spectrum antifungal (specific mechanism is unknown)
-effective in treatment of dermatophyte infections
-ineffective in treatment of cutaneous candidiasis
AE = local skin irritation
Available as a cream, aerosol, topical powder
-good option for prevention
-effects are seen after 2 weeks

Question 8

NON P - Undecylenic acid (fungicure and generics)
classification
mechanism of action
effective in treatment of ____ and ____
adverse effects:
nonprescription preparations currently available in Canada

Answer 8

-mechanism of action is unknown
-lowest efficacy, low cure rate
effective in treatment of dermatophyte infections
-ineffective in treatment of cutaneous
AE: itching, burning, stinging
available as gel, liquid, cream, ointment, powder or spray

Question 9

NON P - Nystatin 100 000 units/g
classification
mechanism of action
effective in treatment of ____ and ____
adverse effects:
nonprescription preparations currently available in Canada

Answer 9

C: polyene
-fungistatic or fungicidal, binds to sterols in cell membrane
-effective for candidal infections
-ineffective in treatment of dermatophyte infections
-available as cream or ointment
-AE: rarely irritation

Question 10

What are 3 prescription products?

Answer 10

Topical Ciclopirox
Terbinafine
Ketoconazole

Question 11

Topical ciclopirox
classification
mechanism of action
effective in treatment of ____ and ____
adverse effects:
available as”

Answer 11

C: hydroxypyridone
Broad spectrum agent: effective against dermatophytes and yeast
Fungicidal in vitro, exact mechanism of action unknown
AE: pruritus, burning, stinging, skin sensitivity, contact dermatitis
Available as Loprox 1% cream or lotion, Stieprox 1.5% shampoo
slightly more effective than clotrimazole/miconazole

Question 12

Terbinafine
classification
mechanism of action
effective in treatment of ____ and ____
adverse effects:
available as”

Answer 12

C: allylamine
Broad spectrum fungicidal agent: topical: fungicidal to dermatophytes but only fungistatic to candida
AE: for topical treatment: redness, irritation/bnurning, contact dermatitis
after terbinafine is topically applied, has a half life of 14 to 35 hours and <5% is absorbed
available as: oral tablet, cream or spray
-continues to work even after patient stops taking it
(important to note that 1 week terbinafine = 4 weeks clotrimazole/miconazole)

Question 13

Ketoconazole
classification
mechanism of action
effective in treatment of ____ and ____
adverse effects:
available as”

Answer 13

C: azole
Broad spectrum: effective in treatment of dermatophyte and yeast infections
Prescription products include cream, oral tablets
shampoo is available without a prescritpion
Oral dosage - risk of potentially fatal liver toxicity and therefore should only be used for serious or life threatening systemic fungal infections
Oral dosage - risk of potentially Fatal liver toxicity and therefor should only be used for life threatening systemic fungal infections

Question 14

Dermatophytes generally refers to the various ____infections
requires ____keratin for growth/proliferation
affect ___layer of the epidermis, hair, skin, and nails
generally spread by
1.
2.

Answer 14

tinea
dead
top
direct contact through person to person or person to famine
soil to human or animal to human (unlikely)

Question 15

How do you put the cream on the area infected by a dermatophyte?

Answer 15

1-2 cm outside the affected area

Question 16

What are the three most common dermatophytes pathogens in skin infections?

Answer 16

trichophyton
microsporum
epidermophyton

Question 17

Tinea Corporis - ringworm of the body
what are the signs and symptoms?

Answer 17

affected area often occurs on skin of the trunk, face, and extremeties
annular (ring like), circular, erythematous, flat, scaly patches
reddened, raised edges with vesicles and with margins that clearly transition from abnormal to normal skin, with an inner area clear
itching is variable and dependent on patient
(or in easy words, there are edges with clear margins, a clear area between infected skin and non infected skin)

Question 18

The fungus generally likes…(think temperature)

Answer 18

warm, moist areas, tight clothing

Question 19

Tinea Corporis (ringworm of the body)
differential diagnosis consider

Answer 19

psoriasis
contact dermatitis
seborrheic dermatitis
nummular eczema
Lyme disease
pityriasis rosea

Question 20

How can you distinguish between psoriasis and tinea corporis?

Answer 20

in tinea corporis there are fine scales, not as silvery whereas in psoriasis, they are thick and grey/silvery

Question 21

Tinea corporis - management
what are some non pharmacological suggestions?

Answer 21

1. skin hygiene (clean) and dry
2. avoid excessive irritation by towels
3. wear loose fitting cotton clothes
4. wash clothes and linens separately from non-infected individuals laundry

Question 22

Tinea corporis - management
what are some non prescription topical options?
What is an important thing to mention when counselling patients on how to use these products?

Answer 22

-clotrimazole or miconazole - 1st line
apply to affected area for 4 weeks
-tolnaftate is less effective than azalea options
-Undecyclenic acid lacks comparative evidence of efficacy compared to other options, may be helpful

with the non prescription, treat until the area is clear, then 1 week beyond that to prevent reoccurrence

Question 23

Tinea corporis - management
what are some prescription topical options?

Answer 23

Ketoconazole, terbinafine, ciclopirox
-treatment duration is less with terbinafine (once daily for 1 week)

Question 24

Tinea cruris (Jock Itch)
affected areas?
often concurrent with ?

Answer 24

bilateral upper inner thigh
groin/pubic area
gluteal (anal) cleft
scrotum and penis are not usually affected
often concurrent with tinea pedis

Question 25

Tinea cruris (Jock Itch) signs and symptoms Characterisitcs of the lesions?

Answer 25

well marginated with defined, raised borders erythematous ring shaped quite pruritic (itchy) lesions are red brown, scaly small vesicles (little bumps fluid filled) may be seen at the margin

Question 26

Tinea cruris (Jock itch) risk factors name 4

Answer 26

warm and humid condition wearing wet or tight clothes immunocompromised individuals genetics

Question 27

Differentiate between Jock Itch and Pubic lice infections

Answer 27

jock itch and pubic lice are both in the groin area. In jock itch, there would be no lice present (consider history). in pubic lice infections, there would be a "spotted appearance" and lice present appearing as yellow/brown and skin may appear bluish and spotted

Question 28

when would you refer a patient?

Answer 28

see online section: patient assessment

Question 29

Tinea cruris - management topical anti fungal non prescription?

Answer 29

clotrimaozole or miconazole (either or is ok) for 2 to 4 weeks. once the area is clear, apply for 1 week to prevent reinfection apply to affected area, + 1-2cm

Question 30

Tinea cruris - management topical prescription options

Answer 30

terbinafine, ketoconazole, ciclopirox treatment duration less with terbinafine (once daily for 1 week)

Question 31

Tinea cruris - management what are 4 non pharmacological suggestions?

Answer 31

wear loose fitting cotton clothes powder to reduce moisture avoid excessive irritation with towels wash clothes and linens separately from non-infected individuals

Question 32

Monitoring of therapy when should we see relief of itching?

Answer 32

See table 3. in 1-2 days there should be improvement or relief of itching if no improvement in 1-2 weeks, refer

Question 33

Tinea Pedis (athletes foot) Prevalence? Most common in? -and what's a sign for referral?

Answer 33

will affect up to 70% of the population most common in teenage and adult males <16 years is a sign for referral

Question 34

Tinea Pedis transmission

Answer 34

direct (contact with infected individual) indirect (contact with contaminated surface) auto inoculation (spread to other parts of the body) think sharing shoes, pool, shower, etc

Question 35

Tinea pedis risk factors

Answer 35

warmth and dampness creating moist conditions occlusive foot wear diabetes immunosuppression peripheral vascular diseases occluded skin poor hygiene obesity trauma

Question 36

Tinea Pedis subtypes 4 subtypes

Answer 36

chronic interdigital vesicular moccasin type acute ulcerative disease

Question 37

Tinea Pedis subtype Chronic Interdigital

Answer 37

Most common type of infection - fissures, scaling, maceration - generally self treatable occurs between the 4/5th and or 3/4 toes moist and warmth conditions contribute to worsening

Question 38

Tinea Pedis Vesicular

Answer 38

small vesicles on the instep of one or both feet some scales between toe webs most prevalent during the summer months

Question 39

Tinea Pedis Moccasin type

Answer 39

chronic diffuse scaling with mild inflammation on the soles of the feet - generally found on both feet often involve nails (refer)

Question 40

Tinea Pedis Acute Ulcerative Disease

Answer 40

Macerated, weepy lesions on soles of foot hyperkeratosis and strong odour often present may involve secondary infection with gram negative bacteria (refer)

Question 41

When do you refer for Tinea...

Answer 41

-patient is at risk of delayed wound healing -child <16 years old -lesion: weeping and severely inflamed or oozing pus or eczematous or painful -toenail affected

Question 42

Tinea Pedis - non pharmacological suggestions

Answer 42

emphasize proper footcare/hygiene (wash feet daily, dry between toes) avoid occlusive and tight fitting footwear change to dry socks 2-3 times a day change or alternate shoes avoid being barefoot in public areas do not share personal items

Question 43

Tinea Pedis management - topical anti fungal non-prescription

Answer 43

clotrimazole or miconazole BID for up to 4 weeks (including 1 to 2 weeks after skin has cleared to prevent recurrences) -apply to affected area

Question 44

Treatment of Tinea Pedis ONLY prescription options

Answer 44

Ciclopirox: apply to affected area twice daily for 4 weeks Terbinafine (cream or spray): 1 week up to 4 weeks (has a higher cure rate versus other topical antifungals)

Question 45

What is the importance of treating tinea fungal infections?

Answer 45

without it, can lead to ulceration complications can be secondary bacterial infections

Question 46

what is Onychomycosis?

Answer 46

fungal nail infections toe nail infections are more common than fingernail infections

Question 47

Onychomycosis ___% nail issues

Answer 47

cause of about 50% of nail issues infection rate for toenails is approx 6/4% of the Canadian population, incidence increases with age more frequently toenails than fingernails quality of life can be affected (can be painful, nail can separate)

Question 48

Onchomycosis Pathophysiology most commonly due to? Acute or chronic?

Answer 48

most commonly due to dermatophytes (trichophyton, epidermophyton, microsporum) chronic infection

Question 49

What are the 3 subtypes of onychomycosis? what are the signs and symptoms associated with each subtype?

Question 50

Onychomycosis risk factors?

Answer 50

increased age family history or genetics immunodeficiency co morbid conditions such as diabetes, peripheral vascular disease, psoriasis smoking tinea pedis frequent nail trauma sport participation

Question 51

Onychomycosis differential diagnosis of fungal nail infections

Question 52

Onychomycosis, a referral is required. why?

Answer 52

diagnosis confirmed through microscopy, biopsy or culture. often combination of culture and microscopy used

Question 53

For onychomycosis, what are appropriate non-pharmacologic suggestions that can be provided?

Question 54

Onychomycosis treatment endoints

Answer 54

mycological cure (fungus gone) or clinical cure/efficacy (nail has returned to normal) toenails generally need longer duration of treatments compared to fingernails

Question 55

Onychomycosis oral vs topical options

Answer 55

oral therapy has higher efficacy formulations such as creams, ointments, powders and solutions do not pass through the nail plate topical nail lacquer delivers the medication by evaporating and producing an occlusive film that contains a high concentration of the medication

Question 56

What are onychomycosis oral treatments?

Answer 56

terbinafine > itraconazole >> fluconazole

Question 57

Oral treatment terbinafine for onychomycosis? mechanism of action? treatment duration? risk of severe ____ injury, requires close monitoring including baseline and mid treatment ___function ____level drug interaction ____

Answer 57

drug of choice for dermatophyte onychomycosis -is the most effective treatment mycological cure 70% clinical cure rate 38% blocks biosynthesis of ergosterol by inhibiting squalene expoxidase toenails 12 to 24 weeks fingernails 6 to 12 weeks liver injury, liver function, aminotransferase level CYP2D6 inhibitor

Question 58

Onychomycosis prescription topical treatment options what are the two?

Answer 58

ciclopirox 8% nail lacquer -requires daily application for 48 weeks 33% mycological cure and 7% cure rate adverse effects: local skin irritation, temporary alteration to nail appearance 49$/6g efinaconazole 10% topical solution -drops applied once daily for 48 weeks, no removal 54% mycological cure and 17% cure rate adverse effects: irritation of the skin around application site 80$/6ml

Question 59

Onychomycosis what are non prescription options? name 1

Answer 59

propylene glycol urea lactic acid once daily application for up to 24 weeks mycological cure rate about 27% (in those with <50% affected nail) adverse effects: local skin irritation, pain, onycholysis (separation of nail) and frequent whitening and opacity of the nail must wash solution from unaffected skin and hands

Question 60

Onychomycosis monitoring normal appearance of nail may take up to ___months ____recurrence rate, approximately ___% of patients will have infection again within ___ years of treatment

Answer 60

18 months high, 20, 2

Question 61

what are two other types of tinea infections that you would refer for treatment

Answer 61

Tinea Capitis (on scalp) Tinea Barbae (on beard)

Question 62

Pityriasis Versicolor Fungal infection is caused by an infection of the stratum corner by

Answer 62

Malassezia

Question 63

What is the pathophysiology of pityriasis versicolore?

Answer 63

it is an infection of the stratum corner by mallassezia upper trunk common area of occurrence (sebaceous glands are the food source) highest incidence in warm, humid environment, adolescents and young adults refer if causation is unclear, patients may require further assessment

Question 64

What is a visible distinguishable sign of pityriasis versicolor or what does the name mean

Answer 64

scaly pigmentation that is either hypopigmented or hyper pigmented

Question 65

what are signs and symptoms of pityriasis versicolore?

Answer 65

change in cutaneous pigmentation, lesions may be hypo pigmented or hyper pigmented lesions occur on the back, chest and upper arms individual lesions are small but can coalesce to form larger patches scraping lead to slight scale forming generally only a cosmetic issue itching is rare NOT contagious NOT a result of poor hygiene -generally a part of our natural skin flora

Question 66

Pityriasis versicolor non pharmacological suggestion

Answer 66

reduce moist environments and avoid oil on infected skin

Question 67

Pityriasis versicolor what are non prescription treatment options?

Answer 67

1. keotoconazole 2% shampoo (used like a lotion) -applied to affected area, leave on for 5 minutes then wash off -one time application or once daily for 3 days -clinical cure rate approx 70% 2. topical azalea creams (clotrimazole or miconazole): apply twice a day for 2 weeks -similar efficacy to keoconazole 3. Selenium sulfide 2.5% suspension -apply to affected area and lather with a little water, leave on skin for 10 minutes then wash off. use once daily for 7 to 14 days You can use it for prevention: use once or twice a month for prevention (reduces recurrence to 15%) Note recurrence Is common

Question 68

Pityriasis versicolor what are prescription treatment options?

Answer 68

topical ciclopirox (efficacy similar to topical ketoconazole) topical ketoconazole cream formulation topical terbinafine (less evidence of efficacy)

Question 69

Cutaneous Candidiasis Cause?

Answer 69

most frequently due to Candida albicans leading to an intertrigo infection infections occur when pH of the skin is increased, other normal flora (bacteria) is removed due to antibiotics, increased glucose in sweat and/or moist, warm conditions note that Candida albicans is a part of the normal flora, but it can overgrow

Question 70

What are risk factors of cutaneous candidiasis?

Answer 70

diabetes mellitus malignancy obesity tropical environent medical conditions such as neutropenia, HIV infection, psoriasis use of corticosteroids (because they suppress the immune system) individuals who have hands in water excessively can experience candida paronychia

Question 71

Cutaneous Candidiasis signs and symptoms affected areas? presentation?

Answer 71

affected areas is where moisture can gather, skin folds such as groin, axillae, gluteal region, under breasts, skin folds, hands presentation is bright red, moist skin surface, irregular scalloped borders and satellite papule or pustules outside of border itching and soreness

Question 72

When do you refer cutaneous candidiasis?

Answer 72

-unsuccessful initial treatment -condition extensive or widespread -recurrent infection -ssytemic symptoms (fever? fatigue?) -signs of secondary infections -immunocompromised

Question 73

Cutaneous Candidiasis management - what are some non pharmacological therapy approaches?

Answer 73

keeping the area dry bathe daily avoid tight clothing cool water compresss and then allow area to air dry

Question 74

Cutaneous Candidiasis management - what are topical anti fungal non prescription options?

Answer 74

clotrimazole or miconazole (apply twice a day for 3 weeks) -nystatin cream/ointment (apply twice a day for 2-3 weeks)

Question 75

cutaneous candidiasis management - what are topical prescription options?

Answer 75

ketoconazole, ciclopirox, terbinafine