5. Dermatophyte Infection:
Cause
1. Trichophyton - skin, hair and nails
2. Microsporum - skin and hair
3. Epidermophyton - skin and nails
• Dermatophytes invade only onto Stratum corneum and
the inflammation caused is the outcome of delayed
hypersensitivity or the metabolic products of fungus.
• Severity of infection: Zoophilic fungi > Anthropophilic
fungi
6. Tinea pedis (Athelete’s foot):
• M/c type
• Organisms :
a. Trichophyton rubrum (m/c and most stubborn)
b. Trichophyton mentagrophytes var. interdigitale
c. Epidermophyton floccosum
• Clinical pattern:
a. Soggy interdigital scaling, particularly in 4th & 5th
interspace (all three organisms)
b. Diffuse dry scaling of soles (usually T. rubrum)
c. Recurrent episodes of vesication (T. mentagrophytes var.
interdigitale or E. floccosum)
7.
8. Tinea unguium:
Nail shows following changes :
• Yellow-brown discoloration & thickening of nail plate that
crumbles easily and so appears tunnelled.
• Subungual hyperkeratosis
• Onycholysis
Patterns:
Distal/lateral Subungual variety (m/c)
Superficial white variety
Proximal subungual variety.
9.
10. Tinea manuum:
• Often associated with Tinea pedis
• Lesions manifest as unilateral, well-defined plaques or as
diffuse erythema of the palms with accumulation of fine
scales in the creases.
11.
12. Tinea cruris:
• Common
Sites :
• Groins, Genitalia, Pubic area, Perineal and Perianal areas
Predisposing factors:
•Summer & Rainy seasons
• Occlusion; use of synthetic clothes
• Males > Females
• Adults > Children
13. Tinea cruris:
Morphology:
• Arcuate or annular, sharply demarcated plaques with
peripheral scaling, papulovesiculation and pustulation.
• Chronic lesions may show hyperpigmentation, nodulation
and lichenification in centre.
14.
15. Tinea corporis:
Sites : Glabrous skin, except palms, soles and groins
Variants:
• Tinea incognito ( modified by steroid therapy)
• Tinea faciae ( Cheeks of children)
• Tinea barbae ( Inflammatory swelling with alopecia, in
beard region)
16.
17. Diagnostic features of T. corporis/cruris:
•Itchy dermatosis
• Annular/ arcuate lesions
• Peripheral papulovesiculation & scaling with a relatively
clear centre
18. Tinea capitis:
• Usually a disease of children
• Anthropophilic fungi – bald and scaly areas, with minimal
inflammation and hairs broken off 3-4mm from scalp
• Zoophilic fungi – induce more intense inflammation with
boggy swelling, pustulations and lymphadenopathy.
Patterns:
• Noninflammatory tinea capitis
• Inflammatory tinea capitis
• Favus (T. schoenleinii/ cicatricial alopecia)
19.
20. Diagnostic features of T. capitis:
• Patient usually children
• Non-inflammatory/inflammatory patch of alopecia
• Easy, painless pluckability of hair
29. Terbinafine :
• Fungicidal
• Indications – Dermatophytic infections [ DOC for
extensive tinea infection and tinea unguium; ineffective
in pityriasis versicolor and candidal infection.]
• Dose – 250mg OD. With development of resistance,
500mg OD being used.
•S/Es – GI side effects, Alteration in tastes and skin
rashes
30. Griseofulvin :
• Fungistatic
• Indications – resurgent use, with development of
resistance to terbinafine. [DOC in T. capitis; ineffective
in pityriasis versicolor and candidal infection.]
• Dose – 10mg/kg daily of ultramicronized formulation,
after fatty meal
• S/Es – may cause persistant headdache, GI side effects
and skin eruptions. (Common cause of photosensitive
reaction)
• Avoid in – Pregnants and in pt. with liver failure,
porphyria and systemic lupus.
31. Itraconazole :
• Fungistatic
• Indications – broad-spectrum antifungal agent,
effective in dermatophytic infections, pityriasis versicolor
and candidal infection. (Generally used in
onychomycosis)
• Dose – 200-400 mg, to be taken with meals
•S/Es – GI side effects and hepatotoxicity.
• Avoid in – Children, Pregnant and lactating women.
32. References :
• Illustrated Synopsis of Dermatology and
Sexually Transmitted Diseases. Khanna Neena
• Textbook of Clinical Dermatology. Sehgal
Virendra N.
