Dermatophytes Flashcards
Term for Ringworm disease
Dermatophytosis
General term for any skin disease
Dermatomycosis
Dermatophytes
Keratinophilic fungi that hydrolyzes keratin (skin, nails, hair) as source of Nitrogen
Agent for Ringworm Infection
Tinea
Active Part of Ringworm
Edges of the ring or the outer ring of an active progressing infection
Risks in developing Tinea Infection
Skin or Scalp Injuries
Poor Hygiene
Wet skin
Match Me
- Face a. Pedis
- Body b. Ungunium
- Nails c. Capitis
- Scalp d. Barbae
- Foot e. Manus
- Groin f. Cruris
- Beard g. Corporis
- Hand h. Faciei
Face - faceie Body - Corporis Nails - Ungunium Scalp - Capitis Foot - Pedis Groin - Cruris Beard - barbae Hand Manus
Three Genera of Dermatophytes
Microsporum “ Spindle shaped” - SKIN:HAIR
Trychophyton “Pencil shaped” - SKIN:HAIR:NAIL
Epidermophyton “Club shaped” - SKIN:NAIL
Epidermophyton flocossum
Microscopoic: CLUB SHAPED MACROCONIDIA
Septate Hyphae, Thickened wall
Old culture - Macroconidia may transform to Chlamydoconidia
No microconidia
Microsporum
Spindle Shaped
Thick Rough walled, Curved Tip
Wood Lamp - Bright Green
M. audonii “Anthrophophilic”
Microscopic:
Spindle Shaped Macroconidia (longer and smoother)
PICTINATE HYPHAE
Chlamydospores (Terminal/Intercillary)
Macroscopic:
Mousy fur in textures
Grayish white to tan “cottony white”
Reverse: Salmon/Peach (PDA); Yellowish Brown (SDA)
Rice grain: Negative/Late *differentiate M. canis
Biochem:
Urease (+); Rice Agar (-); BCP (+)
Diagnosis: ECTOTHRIX INFECTION
Differentiate. Ectothrix vs. Endothrix
Ectothrix - growth OUTSIDE shaft
Endothrix - growth INSIDE shaft
Positive Reaction of BCP
Alkaline Medium - Dark purple-blue Color
M. canis “Zoophilic”
Microscopic:
Septate Hyphae
Large Spindle Shaped macroconidia
Echinulate Thick Walls and a distinct KNOB-LIKE ENDS
Macroscopic:
Yellow Pigment
Reverse - Bright Yellow
Rice Medium - Rapid Growth (+)
M. gypseum “Geophilic”
Microscopic:
Oblong Macroconidia with rounded ends
6 compartment cells
Thin Walled
Macroscopic:
Pale Cinnamon colored red surface
Deep cream to tawny buff
Reverse - Cinnamon buff to brown
Diagnosis: Ecothrix infection *(Do not fluoresce in Wood Lamp)
Two types of Trichophyton rubrum
- Downey Type (Tinea pedis)
2. Granular Type (Tinea corporis)
Parent strain of the Downey type T. rubrum
T. rubrum Granular Types
T. rubrum “Anthropophilic”
Microscopic: Teardrop shape microconidia Uncommon pencil shaped macroconidia Arthroconidia from Hyphae *BOTH MICRO-MACROCONIDIA ARE SEEN
Macroscopic:
Pink to white pigment
Downey cotton
Reverse - Blood Red (PDA)
T. mentagrophytes “Anthropophilic and Zoophilic”
Microscopic: ROUND CLUSTERING “GRAPE-LIKE” MICROCONIDIA
Spiral Hyphae
Sub spherical-Pyriform microconidia
Spherical chlamydoconidia
Macroscopic: Granular, Velvety, Downey
Diagnosis:
+ Urease
+ Hair Perforation
T. mentagrophytes “Anthropophilic and Zoophilic”
Microscopic: ROUND CLUSTERING “GRAPE-LIKE” MICROCONIDIA
Spiral Hyphae
Sub spherical-Pyriform microconidia
Spherical chlamydoconidia
Macroscopic: Granular, Velvety, Downey
Diagnosis:
+ Urease
+ Hair Perforation
T. verrucosum
Microscopic:
RAT TAIL Shaped Macroconidia
Antler Hyphae “Favic chandelier Hyphae”
Chlamydospores at 35C
T. schoenleini
Microscopic:
Swollen Tips - NAIL HEADS
Favic Chandelier - ANTLER SHAPED
T. schoenleini
Microscopic:
Swollen Tips - NAIL HEADS
Favic Chandelier - ANTLER SHAPED
Hair infection in HONEYCOMB DESTRUCTION of the hair shaft
FAVUS “Tinea favosa”
Treatment for Tinea Capitis
Selenium sulfide shampoo
Itraconazole
Terbanifine Hydrochloride
