SUPERFICIAL FUNGAL INFECTIONS Flashcards
1
Q
Outline the 3 genera of Dermatophytic fungi causing tinea infections
A
Trichophyton
Microsporum
Epidermophyton
2
Q
Why are dermatophtes restricted to the non viable skin?
A
because most are unable to grow at 37°C
or in the presence of sebum.
3
Q
Which dermatophtes affects the hair?
A
Trichophyton and Microsporum
4
Q
Which dermatophtes affects the nails?
A
Trichophyton and Epidermophyton
5
Q
The inflammation caused by Dermatophytes is due to what?
A
Due to metabolic products of the fungus or to delayed hypersensitivity
6
Q
How are ringworm infections transmitted?
A
by DIRECT CONTACT with materials (e.g. infected scales, hairs), animals, or soils
7
Q
Classify Dermatophytes according to habitat
A
Zoophilic
Anthropophilic
Geophilic
Personal items e.g FOMITES
8
Q
Outline the anthropophilic species
A
T. rubrum T. tonsurans T. violaceum T. schoenleinii M. Aoudouinii M. Ferrugineum Epidermophyton floccosum
9
Q
Outline the zoophilic species
A
T. Mentagrophytea
T. Equinum
M. Canis
10
Q
Outline the Geophilic specie
A
Microsporum gypseum
11
Q
Dermatophyte have a worldwide distribution and reproduce asexually (T/F)
A
False.
Although they have a worldwide distribution, they reproduce sexually producing ASCOSPORE hence belong to the genus ARTHRODERMA
12
Q
Tinea infections occur only in susceptible individuals (T/F)
A
True
13
Q
Most dermatophytes initiate disease by their invasion of dead keratin with their branching, septate hyphae. (T/F)
A
False
It’s ALL Dermatophytes
14
Q
Itemize 3 exogenous keratolytic enzymes produced by dermatophytes
A
Acid proteinases
elastase
keratinases
15
Q
What is known as a Dermatophytid or Trichophytid?
A
A hypersensitivity reaction to a very active fungal infection due to the fungi itself or it’s products
16
Q
What predisposes the host to chronic or recurrent dermatophyte infection?
A
the LACK OF OR A DEFECTIVE cell-mediated immunity/delayed hypersensitivity /inflamtory response
17
Q
Describe in details what you expect to see on a KOH MOUNT preparation of a tinea infection
A
translucent branching, rod-shaped filaments (hyphae) of uniform width with lines of separation (septa) spanning the width and appearing at irregular intervals.
18
Q
If the infection was actually due to candida what would you expect to see on KOH MOUNT preparation?
A
Elongated yeast forms(pseudohyphae) without true septations
19
Q
What other investigations would you use to confirm the diagnosis of a tinea infection?
A
CULTURE
WOOD’S LIGHT EXAMINATION
20
Q
Why is it important to do a culture? And name 2 types of agar used?
A
It’s used to identify the species of dermatophytes.
Mycosel agar
Sabouraud agar
21
Q
All of the dermatophytes capable of invading hair will induce fluorescence (T/F)
A
False
Its only some
22
Q
Mention the genus of Dermatophytes capable of being identified under Wood’s light?
A
Microsporum
Trichophyton
23
Q
What colour do Microsporum and T. schoenleinni appear on wood’s light?
A
Microsporum - GREENISH YELLOW
T. schoenleinii - PALER GREEN
24
Q
The wood’s light is an essential tool in the management of the patients in areas where favus infections are prevalent
A
True
And Microsporum too
25
Which zoophilic Dermatophypte commonly causes Tinea capitis?
Microsporum canis
| Commonly found in cats and dogs
26
Itemize 3 factors that predispose children to Tinea capitis
Poor hygeine
Prolonged moist skin
Minor skin or scalp trauma
27
Which of the tinea infections may be seen as an epidemic
Tinea capitis
28
Ringworm infection of the body, trunk or extremities is called? And is commonly caused by what genus?
Tinea corporis
| Trichophyton
29
Fungal infection of the feet/athlete's foot is k no own as what? And what genus commonly causes this?
Tinea pedis
Epidermophyton floccosum
Trichophyton sp
30
What factors predispose individuals to Tinea pedis
Poor hygiene
| Prolonged wearing of tennis shoes
31
Ringworm infections around the bearded area is know as
Tinea barbae
32
Ringworm infection of the face but not including infection of the bearded area is know as
Tinea faciei
33
Ringworm infection of the nail bed is known as? It's otherwise called? What organism causes it?
Tinea unguium
Onychomycosis
Trichophyton spp
34
What age group are more predisposed to Tinea capitis
children between 3-7 years of age
35
What clinical signs accompany tinea capitis?
cervical or occipital lymphoadenopathy
| alopecia
36
Itemize 5 clinical types of tinea capitis
```
Non-inflammatory black dot pattern
Inflammatory tinea capitis(KERION)
Seborrhoeic dermatitis like (GREY PATCH TYPE)
Pustular type
Favus
```
37
One or multiple inflamed boggy red tender areas of alopecia with pustules on and/or in surrounding skin.
KERION(honey-comb)
38
Mowed wheat field appearance of the scalp
Seborrhoeic dermatitis like(GREY PATCHY TYPE)
39
Extensive hair loss with atrophy, scarring and so called scutula
FAVUS
40
What does SCUTULA mean?
Yellow adherent crusts present on the scalp
41
What genus is commonly isolated from the "grey patch" type of tinea capitis
Microsporum canis
42
What genus is commonly isolated from the "black-dot" variant of tinea capitis?
Trichophyton tonsurans
43
What clinical type of tinea capitis results in SCARRING ALOPECIA if not treated promptly?
Inflammatory tinea capitis(KERION)
FAVUS
The rest can cause non-scarring alooecia
44
What clinical type of tinea capitis occurs without scaling or significant hair loss.
PUSTULAR TYPE
45
What investigations would you want to do in a suspected case of Tinea capitis?
WOOD'S LIGHTexamination of Plucked hair
DIRECT MICROSCOPY in 10% KOH WET MOUNTof scales and hair
CULTURE in sabouraud dextrose agar/mycosel agar
46
What component of sabouraud dextrose agar/mycosel agar suppress saprophyte and bacterial growth?
cycloheximide and chloramphenicol
47
Treatment options for Tinea capitis is not always systemic. (T/F)
False
| It's always systemic!
48
Outline the treatment options of tinea capitis?
GRISEOFULVIN
15-25 mg/kg/day for 2 months
FLUCONAZOLE (Diflucan)
8 mg/kg once weekly for 4-16 weeks.
TERBINAFINE(Lamisil)
20-40 kg body weight: 125 mg daily 2-4 weeks >40 kg body weight: 250 mg daily 2-4 weeks.
49
Outline 3 side effects of Griseofulvin
Headache
GI upset
Photosensitivity
It is well absorbed after fatty meal.
50
What differentiates tinea barbae and Tinea capitis from bacteria Folliculitis clinically?
Like tinea capitis, the hairs are always infected and easily removed while The hair in bacterial folliculitis resist removal (or painful on removal).
51
What are the primary lesions seen in tinea barbae?
Follicular PAPULES
PUSTLES
NODULES
52
What are the secondary lesions seen in tinea barbae?
KERION
| CRUSTS
53
What is tinea barbae commonly mistaken for?
Staph Aureus folliculitis
54
Tinea facialis is otherwise known as?
Epidermal dermatophytosis
55
Are tinea barbae lesions painful or painless?
Painful
56
What is the treatment for tinea barbae?
Same as tinea capitis!
57
Tinea corporis affects glaborous and non glaborous areas of the skin (T/F)
False
| Affects glaborous areas only
58
What other tinea presentations have been found to accompany tinea corporis?
Tinea manuum
| Tinea pedis
59
What is the most common organism causing Tinea corporis and dermatophytosis world wide?
Trichophyton rubrum
60
What are the anthropophilic species causing tinea corporis
Trichophyton rubrum
| Epidermophyton floccosum
61
What are the zoophilic specie causing tinea corporis
Microsporum canis
| Trichophyton mentagrophyte
62
What is the extremely rare geographic specie causing tinea corporis
Microsporum gypseum
63
What is known as tinea corporis gladiatorum?
Tinea corporis due to Skin-to-skin contact among young children and older children participating in sports
64
What is the classic presentation of tinea corporis?
it's the subacute onset of a single (or few) well demarcated annular erythematous pruritic plaque(s) with a raised border and central clearing
65
What are the primary lesions seen in the border
papular
vesicular
pustular
66
What are polycyclic patterns? Under what condition can a patient present in this manner? How does this correlate with treatment?
Extensive and sever presentations characterized by multiple plaques which coalesce often into unusual paterns
Underlying immunodeficiency
Difficult to treat with topical therapy alone
67
Outline the characteristic symptoms of tinea corporis?
```
"SPECC"
Scaling
Pruritus
Erythema
Central clearing
Concentric rings
```
68
What is tinea incognito
It's a cortisone(OTC TOPICAL corticosteroid therapy) induced alteration in the characteristic morphological features or classic presentation of tinea infections
69
What other medication has been implicated in tinea incognito?
topical calcineurin inhibitors (pimecrolimus )
70
What are the features of tinea incognito?
Thinned skin
Reduce inflammation
Cortisone induced morphological changes
Altered morphology, well defined border may be absent
Groin, face, dorsum of the hand affectation
71
Fungal infections of the skin show characteristic fluorescence on wood's light (T/F)
False
| Fungal infections of the SKIN do not flouresce
72
What investigations would you want to do in a suspected case of tinea corporis?
Obtain Skin scrapings from the edge of the lesion
Direct microscopy
culture
73
What are the treatment options for a confirmed case of tinea corporis?
TOPICAL ANTIFUNGALS
whitfield’s ointment
imidazole cream e.g. canestin
GRISEOFULVIN
10-15mg/kg/day in children
FLUCONAZOLE
150mg/wk 2-4wks
ITRACONAZOLE
100mg qd 2wks
TERBINAFINE
250mg /day 1-2wks
74
What population group is Tinea cruris more commonly found?
Commonly seen in MEN
| It's rare in children
75
What is the classic presentation of Tinea cruris?
A half moon shaped red brown plaque often pruritic which forms as a well-defined scaling, and sometimes a vesicular border, advances out of the crural fold onto the thigh.
76
Mention 4 ways by which tinea cruris can be differentiated from candida infection of the groin clinically?
```
CANDIDA INFECTIONS
Scrotal involvement is common
Bilateral involvements is common
Typical fringe of scales at the border
Satellite papules and pustules seen
```
77
Griseofulvin is routinely used in the treatment of tinea cruris (T/F)
False!
78
What are the treatment options for a confirmed case of tinea cruris?
```
TOPICAL
Terbinafine 1% cream (Fungicidal, Lamisil) applied twice daily for 1 week.
ORAL
Fluconazole
150 mg once weekly for 2-4 weeks.
Itraconazole
100 mg twice daily for 1 week.
Terbinafine
250mg once daily for 1-2 weeks.
```
79
What is the most common type of fungal infection in humans?
Tinea pedis(Athlete's foot)
80
Itemize the 3 organisms implicated in causing tinea pedis?
Trichophyton rubrum
Trichophyton mentagrophytes
Epidermophyton floccosum
81
What is the most common and most stubborn organism causing tinea pedis
Trichophyton rubrum
82
Mention 3 factors that promote relapse in tinea pedis infection
sharing of wash places e.g. in showers swimming pools
| tight foot wears
83
How does tinea pedis present clinically?
Classical ringworm infection
Interdigital tinea pedis (toe web infection)
Chronic scaly infection of the planter surface (hyperkeratotic or moccasin type of tinea pedis)
Acute vesicular tinea pedis
84
The classic ringworm pattern of tinea pedis is restricted to just the Dorsum of the foot (T/F)
False
| It can appear on any body surface
85
Where is the most common site for interdigital tinea pedis?
The 4th toe web
86
The moccasin type of tinea pedis commonly affects what body area?
The entire sole i.e PLANTAR SURFACE
87
The hyperkeratotic type of tinea pedis is usually restricted to just the soles of the feet (T/F)
False
| The hands may also be infected
88
It is common to see both palms and soles infected simultaneously in hyperkeratotic type Tinea pedis infection (T/F)
False
| It's rare
89
What is the usual pattern of moccasin type tinea pedis infection?
The pattern is infection of two feet and one hand or of two hands and one foot.
90
What is the usual pathogen causing chronic scaly infection of the plantar surface?
Trichophyton rubrum
91
Which clinical sub-type of tinea pedis is associated with a dermatophytid or Id rxn?
It's the acute vesicular tinea pedis otherwise called Bullous sub-type
92
Mr A presented with vesicular eruptions which appeared fused into bullae. Few days later a second wave of vesicles followed shortly in the same area and at distant sites such as his arm, chest, and along the sides of the fingers. He complained that they were really itchy. What would you expect to see on KOH mount prep obtained from the roof of these new itchy vesicles?
NOTHING!
These itchy sterile vesicles represent an allergic response to the fungus and are termed dermatophytid or id reaction.
They subside when the infection is controlled.
93
Outline the primary lesions seen in Bullous sub type of tinea pedis
VESSICLES
| BULLAE
94
Outline the secondary lesions seen in Bullous sub type of tinea pedis
ERYTHEMA
FINES SCALES
EROSIONS
seen on plantar surface of foot
95
How would you counsel a patient who has athlete's foot?
Keep the space in-between the toes DRY and expose to air
wear cotton socks
Do not wear shoes that are too tight or hot.
Change socks daily as this will help prevent re-infection.
96
What are the treatment options for a diagnosed case of athlete's foot?
TOPICAL
Imidazole cream or Whitfield’s ointment twice daily until a week after symptoms have cleared. This usually takes a minimum of 4 weeks
```
ORAL
Griseofulvin
5-7mg/kg/day 6-12wks
Fluconazole
500mg once a wk for 3-4wks
```
97
Tinea unguium is otherwise called
Onychomycosis
98
Finger nails are more commonly affected than toe nails in tinea unguim(T/F)
False
| Toe nails are more affected
99
Tinea unguium is usually associated with what?
Tinea pedis
100
Initial lesions of tinea unguium occur at the proximal end of the nail(T/F)
False
| Begins at the distal end/free edge and spreads proximally
101
Itemize 4 nail changes seen in onychomycosis?
```
Subungual hyperkeratosis
Onycholysis
Nail ridges/furrows
Brown or yellowish nail discolouration
Lack of nail lustre and friability
```
102
Fingernail lesions are usually accompanied with what?
with a chronic Trichophyton rubrum infection of the skin of the hands.
103
Mention 2 investigations to be done in a patient with tinea unguium?
SCRAPING of subungual keratinized debris
| NAIL CLIPPINGS for direct microscopy and culture
104
Mention 3 treatment options for onychomycosis?
Thickened toenails softened using Whitfield’s ointment and then thinned with a file
griseofulvin 1g daily until the affected nails have grown out completely
Nail extraction under local anaesthetics and adequate griseofulvin cover
105
How long should Griseofulvin be used for finger nails?
6-8 months
106
How long should Griseofulvin be used for toe nails?
12-16 months
107
Recurrence rarely occurs in tinea unguium infection (T/F)?
False
| Recurrence is common
108
Tinea of the Dorsum of the hand has the appearance of dry, diffuse keratolytic form of Tinea on the soles (T/F)?
False
| It's Tinea of the palm!
109
Tinea of the dorsum of the hand has all the features of Tinea corporis (T/F)?
True
110
Tinea manuum is frequently in association with Tinea pedis
True
111
Treatment is the same as for Tinea unguium and recurrence is common (T/F)?
False
| Treatment is the same as for Tinea pedis
112
Mention 3 species of organisms causing Ptyriasis vesicolor?
Malassezia furfur
Malassezia restricta
Malassezia globosa
113
Ptyriasis vesicolor may be caused by a Dermatophytic organism (T/F)?
False!
114
Ptyriasis vesicolor may sometimes be infectious (T/F)?
False
| It's non-infectious
115
What substance is released by the organism causing Ptyriasis vesicolor and how does it mediate it's actions?
Azelaic acid
| a competitive inhibitor of tyrosinase which inhibit the increase in pigment production by melanocytes
116
The yeast form of malassezia is implicated in the pathogenesis of Ptyriasis vesicolor (T/F)?
False!
| It's the mycelia form(malassezia) not yeast(ptyrosporum)
117
Itemize 5 predisposing factors to pityriasis veraicolor?
```
Heat
Moisture
Working in hot humid factories and occlusion of skin
Corticosteroid Creams (habitual use)
Immunosuppressive therapy
Malnutrition
Chronic debilitating pulmonary tuberculosis
Cushing’s syndrome
```
118
What are the commonly affected areas in pityriasis vesicolor?
Face
Neck and Shoulders
Chest
Upper back
119
Itemize 2 important investigations in the diagnosis of Pityriasis vesicolor?
DIRECT MICROSCOPY of skin scrapings examined in 10-30% KOH wet mount with slide stained with 1% methylene blue
WOOD'S LIGHT EXAMINATION
120
What characteristics appearance is seen on KOH mount of pityriasis vesicolor?
short branched hyphae and spots (characteristic spaghetti and meat balls appearance)
121
How does pityriasis vesicolor appear on Wood's light examination?
yellow to white fluorescence
122
Itemize 5 treatment options for pityriasis vesicolor?
```
Imidazole cream. (2-4 wks)
Selenium sulphide bath (daily for 3wks)
Itraconazole (200mg/day for 7 days) for stubborn and widespread infections
Fluconazole (300/400mg single dose)
Ketoconazole (300mg single dose)
```
Patient should be informed that after treatment it takes some time for the skin color to return to normal. Sunlight accelerates repigmentation.
123
What is the most common organism causing candidiasis?
Candida albicans
124
The organism causing candidiasis is a recognized commensals of the human GIT (T/F)?
True
125
Itemize 6 predisposing factors to candidiasis?
```
Malnutrition
Pregnancy
Diabetes mellitus
obesity
Immunosuppressive therapy e.g cytotoxic drugs
Hot humid climates
```
126
Candida albicans becomes pathogenic under what conditions?
pregnancy
DM
corticosteroid therapy
long term antibiotic therapy
127
What is the Primary lesion in candidiasis?
Pustule
128
Mention the 3 types of candidiasis?
Oral candidiasis
Chronic paronychia
Genital candidiasis
129
In oral candidiasis the angle of the mouth is mostly affected (T/F)?
False!
| It's the Tongue that's affected most
130
Oral candidiasis can be gotten during birth in infants (T/F)?
True
131
Genital candidiasis may be the first manifestation of HIV (T/F)?
False
| It's oropharyngeal candidiasis
132
A recently identified yeast mostly identified in HIV patients is known as?
Candida dubliniensis
133
What type of candidiasis also occurs in people with advanced stage cancer.
Oral candidiasis
| The two most common species are C. albicans and C. glabrata
134
What are the clinical features of oral candidiasis?
Whitish adherent patches (not easily removed) on an erythematous base
Angular stomatitis (peleche)
Red sores under dentures (denture sore mouth)
Long standing – hyperplasia and thickening of mucosa
135
Mention 4 areas commonly affected in candida intertrigo?
groin
gluteal fold
under pendulous breast
interdigital clefts
136
What are the xteristic lesions in candida intertrigo called?
Satellite lesions(papules)
137
Poor hygiene is a known risk factor for intertrigous candidiasis (T/F)?
True
138
Chronic paronychia is mostly bacterial (T/F)?
False
| It's Acute paronychia
139
Candida paronychia usually presents as a Painless swelling around the nail (T/F)?
False
| It's painful
140
Expression of greenish pus in chronic paronychia suggest what infection?
PSEUDOMAONAS
141
Chronic paronychia is common in what group of people?
Wet workers e.g Dish washers
| Finger sucking
142
Candida vulvovaginitis is not sexually transmitted (T/F)?
False
| Could be sexually transmitted
143
A 35y/o woman complains of vaginal Itching and Creamy white, thick, scanty vaginal discharge. On examination a Swollen red labia with areas of maceration and erosion was seen with spread to the thighs and anus with discrete pustules around the edges of the lesion.
What's the most likely diagnosis?
What are these discrete lesions called?
Candida vulvovaginitis
| Satellite lesions
144
Itemize 4 predisposing factors to candidia vulvovaginitis?
use of broad spectrum antibiotics
pregnancy
low vaginal pH and
diabetes mellitus
145
Candida vulvovaginitis is a slightly uncommon condition in women (T/F)
False
| It's common
146
Candida balanitis affects only uncircumcised penis (T/F)?
False
| Can affect circumcised penis also
147
Candida balanitis is gotten mainly due to poor hygiene (T/F)?
False
| Sexual intercourse with an infected female
148
A 25y/o man presents with Tender, red papules and pustules on the shaft and glans of his penis giving a pink circinate appearance. History is positive for unprotected sexual intercourse and there was also associated whitish discharge
What's the most likely diagnosis?
What treatment options can be offered to this patient?
Candida balanitis
| Application of fluconazole or clotrimazole bd for 7 days
149
What are the components of chronic mucocutaneous candidiasis syndrome?
recurrent, persistent candidiasis of the skin, nails, and mucous membrane without disseminated candidiasis
150
chronic mucocutaneous candidiasis syndrome is first recognized in what group of individuals?
Infants
151
Mention 2 endocrine disorders associated with chronic mucocutaneous candidiasis?
hyperparathyroidism
| Addison’s disease
152
Mention 3 important investigations in the morning of chronic mucocutaneous candidiasis
KOH wet mount
Swabs from suspected areas should be sent for culture.
The urine should always be tested for sugar.
A detailed CMI (cell mediated immunity) work up should be done
153
What are the treatment modalities for chronic mucocutaneous candidiasis?
```
Keep affected area dry
potassium permanganate solution
Any of the imidazole creams or powder
Vaginal tablets (pessaries)
Griseofulvine
Recurrent CMC can be treated with ketoconazole
Treat the underlying cause
```
154
What drug is used in the treatment of recurrent chronic mucocutaneous candidiasis
Ketoconazole
