Superficial Fungi

Question 1

What is the compositions of SDA?

Answer 1

Non-inflammatory ‘black dot’ type

Inflammatory (‘ Kerion’ - rare )

Question 2

Trichophyton rubrum culture

Answer 2

Trichophyton rubrum has a white cottony surface . Microconidia are piriform (pear-shaped) Macroconidia –Pencil shaped .

Question 3

Epidermophyton rubrum

Answer 3

Colonies white , yellow coloured

slow growing & greenish-brown colored reverse pigment .

Question 4

Epidermophyton floccusum fungal hyphae

Answer 4

macroconidia and fungal hyphae

Club shaped , smooth walled-septate.

Question 5

Microsporum Canis

Answer 5

Colonies- flat , spreading, white to cream-coloured , with a dense cottony surface .
Have bright goldenyellow reverse pigment.

Question 6

What is the length of treatment for skin and nail infections with dermatophytosis?

Answer 6

4 -6 weeks for - Skin infections.

Upto one year for - Nail infection.

Question 7

What is the treatment method?

Answer 7

Removal of infected and dead epithelial structure & application of topical and oral antifungal

Question 8

Oral antifugals

Answer 8

Griseofulvin – Oraly –Drug of choice.
Ketaconazole
Itraconazole
Terbinafine

Question 9

What is the cause and presentation of shifting cloud?

Answer 9

Caused by :- Malassezia furfur / Pityrosporum orbiculare .

Disease is characterised by blotchy, hypopigmented or hyperpigmented macular lesion which may be associated with itching.

Question 10

What is shifting cloud associated with and location?

Answer 10

associated with itching, Scattered over the chest , back , abdomen , neck & upper arm. = TINEA VERSICOLOR INFECTION = Malassezia furfur

Question 11

Spaghetti and Meatball Appearance is associated with?

Answer 11

Lotta-Scattered over the chest , back , abdomen , neck & upper arm. = TINEA VERSICOLOR INFECTION = Malassezia furfur

Question 12

What indicates Malassezia furfur on culture?

Answer 12

Fried egg colonies develops in 2 - 4 days at 37oc

Question 13

What is the culture media for M furfur?

Answer 13

Skin scrapings from infected area inoculated in SDA -Sabouraud’s dextrose agar overlaid with film of olive oil

Question 14

What does the smear from of M fufur look like?

Answer 14

Smear from culture shows bottle shaped budding yeast cells

Question 15

Mal furfur is susceptible to?

Answer 15

ketoconazole

Question 16

What is the treatment for a fungus that is light to dark grey on SDA? wHAT IS THE FUNGUS AND WHO IS IT COMMON IN?

Answer 16

Hortaea werneckii = Exophiala werneckii = Cladosporium werneckii common in females, micacanazole

Question 17

What does cladosporium werenckii

cause?

Answer 17

Superficial asymptomatic skin disease , characterised by light brown to black macular areas affecting thickly keratinised region of Palm & Soles .

Question 18

type of fungus of tinea nigra

Answer 18

dimorphic fungus

Question 19

What does the skin scraping for KOH SHOWS?

Answer 19

Skin scraping on KOH shows brownish branched septate hyphae & budding cells.

Question 20

What is Tricosporum beigelii characterized>

Answer 20

Skin scraping on KOH shows brownish branched septate hyphae & budding cells.

Question 21

Creamy white and urease positive is characteristic of?

Answer 21

t beigleii

Question 22

Black piedraie is associated with?Seen with

Answer 22

Black hard nodules on hair shafts of scalp & beard .

Black piedra mostly affects young adults & epidemics in families can occur due to sharing of combs.

Question 23

SDA colonies of black piedra

Answer 23

P.hortae produces reddish brown colonies when grown on SDA.P.hortae produces reddish brown colonies when grown on SDA.

Question 24

What is the treatment of black and white piedra?

Answer 24

Rx - Of - Black & White piedra
Remove hair & apply topical antifungal agents eg. Imidazoles
Amphotericin B lotion.

Question 25

What is the lab diagnosis method?

Answer 25

Nail , Hair clippings , Dermatophytes - Superficial Skin scrapings . ``` Clean the part with 70% alcohol Collect the material in a Sterile Black Paper or a Sterile Petri Dish to - Allow drying of the specimen. Reduce bacterial contamination. Maintain viability. ```

Question 26

Direct Examination

Answer 26

Direct examination - 10 – 20 % KOH. Fungal culture-Sabouraud’s dextrose agar (SDA). Serological tests. Skin tests. PCR And Other Molecular Methods.

Question 27

What is used to investigate scalp lesions and what caution must be taken?

Answer 27

Scalp lesion – Wood lamp’s examination of infected hair – show fluorescence. Stop anti fungals one week prior to collection.

Question 28

How can fungi be seen under the microscope and with what stain?

Answer 28

Scalp lesion – Wood lamp’s examination of infected hair – show fluorescence. Stop anti fungals one week prior to collection.

Question 29

What is the composition of LPCB?

Answer 29

Lactic acid - preserves fungal structure. Phenol – kills any live organism. Glycerol – prevents drying. Cotton blue – imparts blue color to structures.