Dermatomycosis, superficial and cutaneous

Question 1

superficial life cycle

Answer 1

spores adhere to keratinized tissue-> germinate-> secrete keratinase-> invade-> grow

Question 2

Malassezia furfur

Answer 2

-pityriasis versicolor-> multicolored colonization of s. corneum
-hypopigmentation/hyperpigmentation (back, chest, abd, neck, upper limbs)
-young males and females
-high temp/humidity
-direct contact with spores
-Woods lamp-> yellow-green fluorescence appearance of lesion
-dandruff shampoo (selenium sulfide)
topical imidazole

Question 3

Exophiala werneckii

Answer 3

tinea nigra (black/brown) colored macules, hands feet

• direct contact with spores
• skin scraping mixed on slide with KOH-> reveal hyphae and spherical yeast
• oral azoles

Question 4

Superficial

Answer 4

Malassezia furfur, exophiala werneckii

Question 5

Dermatophytes

Answer 5

Geophilic- transmitted thru soil
Zoophillic-> transmitted thru animals
Anthropophillic-> transmitted thru humans
G/Z-> easily treated acute inflammatory infections
A-> mild to chronic infections that are difficult to treat
Ringworms-> tineas

Question 6

Dermatophytes diagnosis

Answer 6

presence of septae, BRANCHING hyphae, or chain of arthroconidia

• skin scraping with KOH-> reveal hyphae and sperhical yeast
• direct examination under woods lamp (green)

Question 7

T. tonsurans, M,audouinii, M. canis (pups kittens), T. verrucosum

Answer 7

tinea capitis

• children
• T. tonsurans in N. America and UK
• overcrowding, poo hygiene
• oral agents, griseofulvin and ketoconazole

Question 8

T. mentagrophytes, T. verrucosum

Answer 8

Tinea barbae

• ringworm of beard
• adult males
• systemic antifungal agents
• contact cattle, dogs, other animals
• person to person

Question 9

T. rubrum, M. canis. T. verrucosum, M. audouinii

Answer 9

Tinea corporis-> ringworm of body
tinea faciei-> infection of hairless areas of skin and face
-direct contact with infected animal, human, clothing
-tropical/subtropical areas
-non-inflammatory lesion-> topical agent
-inflammatory lesion-> systemic agent

Question 10

E. floccosum, T. rubrum, T. mentagrophytes

Answer 10

Tinea pedis-> athletes foot
toes, webs and soles
-vesicular and vesiculobullous tinea pedis
-ulcerative
-footwear, common baths, walking around pools
-non-inflammatory lesion-> topical agent
-inflammatory lesion-> systemic agent

Question 11

E. Floccosum, T. rubrum

Answer 11

Tinea cruris (jock itch)

• ringworm of groin
• men mostly
• high temp, humidity, occlusion of scrotum/groin
• direct contact, indirect contact (objects)
• summer and tropics
• non-inflammatory lesion-> topical agent
• inflammatory lesion-> systemic agent

Question 12

T. rubrum

Answer 12

tinea manus
-infected hands/fingers
dry scaly lesions
-non-inflammatory lesion-> topical agent
-inflammatory lesion-> systemic agent
-non-inflammatory lesion-> topical agent
-inflammatory lesion-> systemic agent

Question 13

T. rubrum, Tmentaprophytes, E. Floccosum

Answer 13

tinea ungium (onchomycosis)

• infection of the nail plate
• nail is variously disfigured and distorted
• elderly because of reduced peripheral circulation, diabetes, increased nail trauma
• poor hygiene
• chronic water exposure
• systemic antifungal medication