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Fungal infections
Dermatophytic infections
(ringworm)
CAUSE
Three genera of dermatophyte fungi cause tinea
infections (ringworm).
 Trichophyton – skin, hair and nail infections.
 Microsporum – skin and hair.
 Epidermophyton – skin and nails..

Dermatophytes invade only into the stratum
corneum
 The inflammation they cause is a result of
metabolic products of the fungus OR
 Delayed hypersensitivity

PRESENTATION AND COURSE

The site and on the strain of
fungus involved
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Tinea of the scalp (tinea capitis)
Tinea of the trunk and limbs
(tinea corporis)
Tinea of beard (Barbae)
Tinea of the nails (unquium)
Tinea pedis (athlete’s foot)
Tinea of the groin (T. cruris)
TINEA PEDIS (ATHLETE’S FOOT)
Most common type of fungal infection in humans.
 Trichophyton rubrum (the most common)
 The sharing of wash places (e.g. in showers) and
of swimming pools predisposes to infection
 Spores in occlusive footwear encourage relapses
 Hyperhidrosis of
sole
 Tinea unguium
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1.
2.
3.
There are three common clinical
patterns.
Soggy interdigital scaling,
particularly in the fourth and
fifth interspace,when
complicated by bacterial
superinfection labeled athlete’s
foot.
A diffuse dry scaling of the soles
(usually T. rubrum)
Recurrent episodes of vesication
(usually T.mentagrophytes)
TINEA OF THE NAILS
/ONYCHOMYCOSIS)
Tinea unquium
 Toe nail infection is usually
associated with tinea pedis.
 The initial changes occur at the
free edge of the nail, which
becomes yellow and crumbly
 Followed by hyperkeratosis,
separation of the nail from its bed
and thickening(onycholysis)
 Usually, only a few nails are
infected & rarely all
 Finger nail lesions are similar,
but less common

TINEA OF THE HANDS/TINEA MANUUM
Usually asymmetrical
 Associated with tinea pedis and unilateral
onychomycosis.
 Unilateral well defined plapues or as diffuse
erythema of palm with a characteristic powdery
scale in the creases.

TINEA OF THE GROIN/TINEA
CRURIS
This is common and affects men
more often than women.
 Predisposing factors:summers or
winter or occlusion by use of
synthetic clothes
 The eruption is sometimes
unilateral or asymmetrical.
 The upper inner thigh is involved
 Lesions expand slowly to form
sharply demarcated plaques with
peripheral scaling.
 Scrotum is usually spared.
 A few vesicles or pustules may be
seen within the lesions.

TINEA OF THE TRUNK AND
LIMBS/TINEA CORPORIS
Characterized by annular or
arcuate plaques with scaling and
erythema most pronounced at the
periphery, relative clearing in the
center and active periphery.
 Few small vesicles and pustules
may be seen within them.
 Lesions expand slowly and healing
in the centre leaves a typical ringlike pattern.

TINEA OF THE SCALP (TINEA CAPITIS)
Usually a disease of children
 Discoid patch of partial
alopecia from which the hair
can easily and painlessly be
plucked.
 Causative organism varies
 Fungi coming from human
sources (anthropophilic
organisms)cause bald and
scaly areas
 With minimal inflammation

Fungi coming from animal sources (zoophilic
fungi) induce a more intense inflammation
 In ringworm acquired from cattle -swelling, with
inflammation, pustulation and
lymphadenopathy-bacterial infection is suspected
 Lesion is called a kerion
 The hair loss associated with it may be
permanent.

Favus : caused by T.schoenleinii
 Characterized by presence of foul smelling
yellowish cup shaped crusts entangling many
scalp hair.
 Often results in cicatricial alopecia

COMPLICATIONS
Fierce animal ringworm of the scalp can lead to
a permanent scarring alopecia.
 A florid fungal infection can induce vesication on
the sides of the fingers and palms
 Epidemics of ringworm occur in schools.
 The usual appearance of a fungal infection can
be masked by mistreatment with topical
steroids(tinea incognito)

‘Tinea incognito’. Topical steroid
applications have thinned the skin
and altered much of the morphology.
A recognizable active spreading edge
is still visible.
DIFFERENTIAL DIAGNOSIS
Area
Differential diagnosis
Scalp
Alopecia areata, psoriasis, seborrhoeic eczema,
carbuncle, abscess
Feet
Erythrasma, eczema
Trunk
Discoid eczema, psoriasis, candidiasis,
pityriasis rosea
Groin
Candidiasis, erythrasma, irritant and allergic
contact dermatitis, psoriasis,
neurodermatitis
Nails
Psoriasis, paronychia, trauma, ageing changes
Hand
Chronic eczema, xerosis,
INVESTIGATIONS
Microscopic examination
of a skin scraping nail
clipping or plucked hair
in KOH mount
 Cultures
 Wood’s light (ultraviolet
light) examination of the
scalp usually reveals a
green fluorescence of the
hairs.
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TREATMENT

Local
Imidazole preparations (e.g. Miconazole & and
Clotrimazole and ketoconazole)
 Terbinafine
 Applied twice daily
 Amorolfine and Tioconazole nail solutions
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Systemic
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For tinea of the scalp or of the nails
For widespread or chronic infections of the skin that have
not responded to local measures.
Terbinafine
Itraconazole
Griseofulvin (drug of choice for chronic dermatophyte
infections)
CANDIDIASIS
CAUSE
Opportunistic pathogen
 Candida albicans, a dimorphous
fungus existing as commensal in
oral mucosa (50% of normal
humans )and vaginal (25%of
normal women)

Commensal becomes pathogenic in presence of following
predisposing factors:
Diabetes
Other endocri.
Antibiotics
Obesity
(friction)
Poor hygiene
candidiasis
Cold hands
Immersion in water
Pregnancy
Oral contraceptive
High humidity,
Occlusive
clothes
Immunosuppression
Systemic
candidiasis
(rare)
Leucopenia
Thymic tumours
Inherited defects
of immunity
Chronic
Mucocutaneous
candidiasis
(rare)
Endocrinopathy
TYPES
Systemic
 Chronic mucocutaneous
 Acute mucocutaneous

ACUTE MUCOCUTANEOUS:
CANDIDA INTERTRIGO
/FLEXURAL
A moist glazed area of erythema
and maceration in body fold
 The edge shows soggy scaling
and outlying satellite
papulopustules.
 Most common under the breasts
and in the armpits and groin
 Can also occur between the
fingers

Typical lesion:
• Central denudation leaving a
fiery red, raw surface
• Thick, white plaques at
periphery
ORAL CANDIDIASIS
Acute pseudomembranous candidiasis(thrush):
most common form
 Seen in infants or elderly with antibiotics or
steroids therapy
 Presents with white adhernt plaques which are
difficult to remove
 On removal erythematous base is revealed.
 Seen over buccal mucosa, tongue, palate and
gingiva.
 Acute atrophic candidiasis: patchy depapillated
area over the dorsum of tongue
 Angular stomatitis
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Oral Candidiasis
GENITAL CANDIDIASIS
Presents as a sore itchy vulvovaginitis
 White curdy plaques adherent to the inflamed
mucous membranes
 Whitish discharge
 In males- similar changes occur under the
foreskin and in the groin
 Diabetes, pregnancy and antibiotic therapy are
common predisposing factors.

PARONYCHIA
Acute paronychia is usually
bacterial
 In chronic paronychia Candida
may be the sole pathogen OR
 It may be found with other
opportunists such as Proteus or
Pseudomonas sp.
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Proximal and sometimes the
lateral nail folds of one or more
fingers become rolled and red
The cuticles are lost and small
amounts of pus can be expressed.
 The adjacent nail plate becomes
ridged and discolored.
 Predisposing factors include wet
work, diabetes and vulval
candidiasis.
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CHRONIC MUCOCUTANEOUS CANDIDIASIS
Persistent candidiasis
 Can start in infancy
 Autosomal recessive and dominant
inheritance forms
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In the Candida endocrinopathy syndrome,
chronic candidiasis occurs with one or more
endocrine defects
Hypoparathyroidism
 Addison’s disease.

Late-onset cases have underlying thymic
tumours.
 Manifest over oral mucosa or skin or nails.
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SYSTEMIC CANDIDIASIS
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Usually seen with
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Severe illness
Leucopenia
Immunosuppression
Lethal within days, without treatment
 Cutaneous or visceral inf.
 Skin lesions are firm red nodules, which can be
shown by biopsy
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Contain yeasts
 Pseudohyphae.
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INVESTIGATIONS
KOH mount shows budding yeast and
pseudohyphae
 Swabs from suspected areas for culture
 Urine for sugar
 In chronic mucocutaneous candidiasis
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Detailed immunological work-up
TREATMENT
Predisposing factors should be sought and
eliminated
 Infected skin folds should be separated and kept dry
 Chronic paronychia -keep their hands warm and dry
 Topical nystatin and the azole group of compounds
are effective and topical or oral antibiotic if
associated infection
 Oral suspensions and oral gels for oral lesions.
 Imidazole pessaries or topical azoles for genital
lesion

False teeth should be removed at night, washed
and steeped in antiseptic or a nystatin solution.
 Systemic therapy:
 Vulvovaginitis;single dose fluconazole 150mg or
itraconazole400mg.weekly dose of fluconazole
150mg for recurrent problem.
 For reccurent oral lesion; fluconazole 150mg
weekly dose.
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In chronic paronychia, the nail folds can be
packed with an imidazole cream or drenched in
an imidazole solution several times a day.
 Genital candidiasis responds well to a single
day’s treatment with either Itraconazole and
Fluconazole.
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PITYRIASIS VERSICOLAR
Chronic often asymptomatic
 Fungal infection characterised by pigmentary
changes.
 Commonly involves the trunk.
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PRESENTATION
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Caused by overgrowth of mycelial form of
commensal yeast pityrosporum ovale/malassezia
furfur
Common in humid region
Common in young adults
In white people ,brown or pinkish oval or round
superficial scaly patch is seen
In racially pigmented or tanned skin
hypopigmented patch is seen as organism
releases carboxylic acid that inhibit
melanogenesis.
DIFFERENTIAL DIAGNOSIS
Vitiligo:differentiation is done by microscropic
examination of the skin scraping:p.versicolar
shows short hyphae and spores has grapes and
banana appearance.
 Tinea corporis
 Pityriasis rosea.
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MANAGEMENT
Topical antifungals:ketoconazole
 Shampoo(2.5%slenium sulphide) applied at night
and washed off the following morning .Repeated
twice at weekly interval.
 Systemic:
 Iatraconazole
 Ketoconazole
 Fluconazole
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