Skin and soft tissues infections
description
Transcript of Skin and soft tissues infections
Skin and soft tissues infections
Classification of mycosesSuperficial and cutaneous
Subcutaneous
Deep (systemic)
Superficial mycoses
Caused by fungi living as
saprophytes
Hair, dead skin and lipids secretions
They don’t provoke any immune
response
No pain or itching
Pityriasis versicolor
Common, mild and chronic infection of stratum corneum
World-wideMore common in tropics and sub-
tropics In temperate regions more common
during summer
Pityriasis versicolor Caused by Malassezia
yeast, which is lipophilic dimorphic
fungus
KOH Parker ink staining
Tinea nigraTypical brown to black, non-scaling macules on
the palmar aspect of the hands.
Note: there is no inflammatory reaction
Cutaneous mycoses Infections in the living parts of the body:
Skin Hair and nail Mucocutaneous membranes Genitalia
Tow types can be recognized Dematophytes infections Non-dermatophytes infections
Dematophytes infections(dematophytosis)
Ringworm (hair and skin)
Favus (hair)
Onychomycosis (nail)
Dermatophytosis(=Tinea = Ringworm)
Infections of the skin, hair and nails
due to a group of related
filamentous keratinophilic fungi
called dermatophytes
Dermatophytes
Microsporum Hair, skinEpidermophyton Skin, nailTrichophyton Hair, skin, nail
Digest keratin by their keratinasesResistant to cycloheximide
Epidemiology and natural habitat
Some have a world-wide distributionSome are restricted to particular
regions About 10 species are common
causes of human infectionClassified into three groups
depending on their usual habitat
Anthropophilic
Human is usual host T. rubrum (foot & nail infections)
E. floccosum (foot & nail infections)
T. tonsurans (scalp infections)
M. audouinii (scalp infections)
Geophilic
Normal habitat is soilCan cause infections in both humans
and animals Microsporum gypseum
Zoophilic
Often associated with a particular
animal
Microsporum canis: cats and dogs
Trichophyton verrucosum: horse and
cattle
Dermatophytosis
Skin: Circular dry lesions Slightly raised red scaly margins Surrounded by red itchy skin Fungus remain restricted to stratum corneum Metabolites provoke inflammation
Hair: Typical lesions → scarring + alopecia
Nail: Thickened, deformed, fragile, discolored Sub-ungual debris accumulation
Dermatophytosis clinical classification
Infection is named according to the anatomic location involved
Clinical manifestation (1) Ringworm
Tinea pedis (athlete's foot) Tinea manuum (hands) Tinea corporis (trunk, neck and back) Tinea cruris (hairy skin around the genitilia) Tinea barbae (hairy skin in the face) Tinea capitis (scalp and eyebrows)
Clinical manifestation (2)
Favus (scalp)
Onychomycosis (nail)
Athlete's foot
(Tinea pedis )
Tinea pedis
Tinea manuum
Tinea manuum
Tinea manuum
Tinea corporis caused by M. canisfollowing contact with infectious cat
Tinea corporis
Tinea of the groin showing typical erythematous lesions on the inner thighs
Tinea of the buttocks
Tinea cruris
Tinea barbae
Tinea capitis caused by M. canisfollowing contact with infectious cat
Tinea capitis showing extensive hair losscaused by M. canis
Favus and OnychomycosisFavus
Special form of tinea capitis
Onychomycosis Fungal infection of nail The term "tinea unguium" is used specifically to
describe dermatophytic onychomycosis
Favus
Tinea capitis showing alopecia
Tinea of the nails caused by T. rubrum
Laboratory diagnosis
50 % of suspicious materials may be negative Hyphae and/or arthrospores is diagnostic Culture is more reliable:
Determined species Source of infection Can be positive even if direct examination is
negative
Hyphal elements seen in skin scraping preparation
Management
Dependant on the clinical setting
Topical or oral antifungal
Infection Recommended Alternative
Tinea unguium[Onychomycosis]
Terbinafine 250 mg/day6 weeks for finger nails,12 weeks for toe nails.
Itraconazole 200 mg/day/3-5 months or 400 mg/day for one week per month for 3-4 consecutive months. Fluconazole 150-300 mg/ wk until cure [6-12 months].Griseofulvin 500-1000 mg/day until cure [12-18 months].
Tinea capitis
Griseofulvin 500mg/day[not less than 10 mg/kg/day]until cure [6-8 weeks].
Terbinafine 250 mg/day/4 wks.Itraconazole 100 mg/day/4wks. Fluconazole 100 mg/day/4 wks
Tinea corporis
Griseofulvin 500 mg/day untilcure [4-6 weeks], often combined with a topicalimidazole agent.
Terbinafine 250 mg/day for 2-4 weeks.Itraconazole 100 mg/day for 15 days or 200 mg/day for 1week.Fluconazole 150-300 mg/week for 4 weeks.
Tinea cruris Griseofulvin 500 mg/dayuntil cure [4-6 weeks].
Terbinafine 250 mg/day for 2-4 weeks.Itraconazole 100 mg/day for 15 days or 200 mg/day for 1week.Fluconazole 150-300 mg/week for 4 weeks.
Tinea pedis Griseofulvin 500mg/dayuntil cure [4-6 weeks].
Terbinafine 250 mg/day for 2-4 weeks.Itraconazole 100 mg/day for 15 days or 200 mg/day for 1week.Fluconazole 150-300 mg/week for 4 weeks.
Chronic and/orwidespread
non-responsivetinea.
Terbinafine 250 mg/dayfor 4-6 weeks.
Itraconazole 200 mg/day for 4-6 weeks.Griseofulvin 500-1000 mg/day until cure [3-6 months].
Oral management options
Non-dermatophytes cutaneous infections
Onychmycosis IntertrigoMucocutaneous candidiasis
Thrush Vulvo-vaginitis
Intertrigocaused by Candida albicans
Red macerated rash under pendulous breasts is a common presentation of cutaneous candidiasis
Candida diaper dermatitis
This condition should not
be considered a primary
Candida infection as it
preceded by an irritant
dermatitis
Subcutaneous Mycoses
Skin, subcutaneous tissues, fascia and bone
LocalizedTraumaMore in tropicsMycetoma, chromomycosis and
sporotrichosis
Mycetoma
Mycetoma
SporotrichosisA 60-year-old woman developed multiple subcutaneous
nodules and abscesses on her right hand and forearm 7 days after finger thorn prick
Sporotrichosis
ClassicalChromoblastomycosis:Fonsecaea pedrosoi
De Hoog, Centraalbureau voor Schimmelcultures
Nodulose chromoblastomycosis(Senegal): Fonsecaea pedrosoi
De Hoog, Centraalbureau voor Schimmelcultures
Management
Difficult
Surgical excision
Itraconazole and other antifungal