1. Selling a Product or Service
FUNGAL SKIN INFECTIONS II
IHAB YOUNIS, M.D.

2. B. Cutaneous mycoses
Infections that extend deeper into the epidermis, as well as hair and nail and caused by dermatophytes:
Tinea capitis
Tinea corporis 
Tinea manus
Tinea cruris
Tinea pedis
Tinea unguium

3. Etymology: L. [caput] head
Tinea capitis
Etymology: L. [caput] head

4. Tinea capitis is the most common pediatric dermatophyte infection worldwide
The age predilection is believed to result from the presence of Malassezia furfur which is part of normal flora, and from the fungistatic properties of fatty acids of short and medium chains in postpubertal sebum

5. Hair invasion by dermatophytes
Ectothrix invasion: Arthroconidia on the exterior of the hair shaft. The cuticle of the hair is destroyed and infected hairs fluoresce under a Wood’s lamp
Endothrix hair invasion: Arthroconidia within the hair shaft only. The cuticle of the hair remains intact and infected hairs do not fluoresce under a Wood’s lamp

6. Hair
Ectothrix
Conidia
Hair
Endothrix
Conidia

7. Types

8. 1-Scaly type:
Erythematous
papule(s) around the hair
shaft appear initially
Subsequently, one or
several patches of scaly
alopecia are seen where
the hairs are broken just
above the level of scalp
The hair looks lusterless
as it is covered with
arthrospores

9. 2-Black dots type:
It is an endothrix infection,
so hairs become notably
fragile and break easily at
the level of the scalp
The rest of the infected
follicle looks like
"black dots". Variable
degrees of scaling and
inflamm-ation are seen

10. 3-Kerion :
Scattered painful pruritic pustular folliculitis generally associated with regional lymphadenopathy and even fever
In about 2-3 %, boggy
nodules studded with
broken hairs and purulent
sticky material "kerion"
appear
Scarring alopecia develops
subsequently

11. 4-Favus :Etymology: L. honeycomb
Dense masses of mycelium
and epithelial debris forming
yellowish cup-shaped crusts
called scutula
The scutulum develops
at the surface of a hair
follicle with the shaft in
the center of the raised
lesion

12. Removal of these crusts reveals an oozing,moist, red base
After a period of years, atrophy of the skin occurs leaving a cicatricial
alopecia and scarring

13. Tinea corporis (circinata)

14. Etiology
Affects the glabrous skin (ie, skin regions except the scalp, groin, palms, and soles)
T rubrum is the most common infectious agent in the world
May result from contact with infected humans, animals, or inanimate objects (eg contact with sports facilities)

15. Clinically Patients can be asymptomatic or pruritic
Begins as an erythematous, scaly plaque that may rapidly worsen
and enlarge
Central
resolution
causes the
lesion to
be annular

16. Scales, crusts, vesicles, and papules often develop, especially in the advancing border

17. Infections due to zoophilic or geophilic dermatophytes may produce a more intense
inflammatory
response than
those caused
by anthropophilic
fungi

18. Majocchi granuloma manifests as perifollicular, granulomatous
nodules typically in a
distinct location, which is
the lower two thirds of the
leg in females

19. Tinea imbricata (Imbricate= Ovelapping) is recognized clinically by its distinct scaly plaques arranged in concentric rings

21. Tinea Cruris
Crus=Fold

22. Etiology
Transmitted by fomites, such as contaminated towels or hotel bedroom sheets
Autoinoculation occurs in 50 % of cases from tinea manuum or tinea pedis
Risk factors for initial infection or reinfection include wearing tight-fitting or wet clothing or undergarments
Tinea cruris is 3 times more common in men than in women

23. Clinically
Patients complain of pruritus and rash in the groin. A history of previous episodes of a similar problem usually is elicited
Large patches of erythema with central clearing are centered on the inguinal creases

25. Lesions extend to the thighs , lower abdomen , pubic area & buttocks
The penis & scrotum typically are spared

26. Scales demarcate sharply the edge

27. In acute infections, the rash may be moist and exudative
Chronic infections typically are dry with a papular annular or arciform border and barely perceptible scale at the margin

28. Chronic infections
modified by the
application of topical
corticosteroids are
more erythematous,
less scaly, and
may have
follicular pustules

29. In response to the infection, the active border has an increased epidermal cell proliferation with resultant scaling
This creates a partial defense by way of shedding the infected skin and leaving new, healthy skin central to the advancing lesion

30. Tinea pedis
Etymology: L. foot

31. Etiology
The first report of tinea pedis was in 1908 by Whitfield, who, with Sabouraud, believed that tinea pedis is caused by the same organisms that produce tinea capitis and that it is a very rare infection !
T rubrum being the most common cause worldwide

32. Tinea pedis is thought to be the world's most common dermatophytosis
Tinea pedis is thought to be the world's most common dermatophytosis. Rippon states that 70% of the population will be infected with tinea pedis at some time
Childhood tinea pedis is rare

33. Risk factors A hot, humid, tropical environment
Prolonged use of occlusive footwear
Certain activities, such as swimming and communal bathing, may also increase the risk of infection
A defect may be present in the immune system, such as in cell-mediated immunity, that predisposes some individuals to tinea pedis, but this is not certain

34. Clinical types 1- Interdigital type
2- Chronic hyperkeratotic type(moccasin)
3-Inflammatory/vesicular type

35. the foot is usually clear,
1- Interdigital type:
The most characteristic type, with erythema, maceration, fissuring, and scaling, most often between the fourth
and fifth toes & often
is accompanied by
pruritus
The dorsal surface of
the foot is usually clear,
but some extension onto the plantar surface of the foot may occur

36. 2-Chronic hyperkeratotic type(moccasin)
Chronic plantar
erythema with slight
scaling to diffuse
hyperkeratosis that
can be asymptomatic
or pruritic
Both feet are usually
affected

37. Typically, the dorsal surface of the foot is clear, but, in severe cases, the condition may extend
onto the sides of the
foot

38. 3-Inflammatory/vesicular type:
Painful, pruritic vesicles or bullae
Most often on the
instep or anterior
plantar surface
After they rupture,
scaling with
erythema persists
Cellulitis,lymphangitis
and adenopathy can
complicate this type

39. Dermatophytid reactions are associated with vesicular tinea pedis
They mimic dyshidrosis (pompholyx)
They develop on the palmar surface of one or both hands and/or the sides of the fingers as papules, vesicles, and,
occasionally,
bullae or
pustules may
occur, often
in a symmetrical
fashion

40. This is an allergy or hypersensitivity response to the infection on the foot, and it contains no fungal elements. The specific explanation of this phenomenon is still unclear
Distinguishing between a dermatophytid reaction and dyshidrosis can be difficult. Therefore, a close inspection of the feet is necessary in patients with vesicular hand dermatoses
The dermatophytid reaction resolves when the tinea pedis infection is treated, and treatment of the hands with topical steroids can hasten resolution

41. Tinea Manuum
  Etymology: L. hand  

42. It is less common than tinea pedis
Erythema and hyperkeratosis of the palms and fingers affecting the skin diffusely is the commonest variety, and is unilateral in about half
the cases
The accentuation of the
flexural creases is a
characteristic feature

43. Other clinical variants include crescentic, exfoliating scales, circumscribed, vesicular patches, discrete, red papular and follicular scaly patches, and erythematous, scaly sheets on the dorsal surface of the hand. The latter forms are more likely to be zoophilic
When the palms are
infected, the feet are also
commonly infected. A typical
pattern of involvement is
either one hand and both feet or both hands and one foot

45. Tinea Barbae

46. Etiology
The mechanism that causes tinea barbae is similar to that of tinea capitis. In both diseases, hair and hair follicles are invaded by fungi, producing an inflammatory response
Currently, tinea barbae is infrequent around the world
Tinea barbae was observed more frequently in the past when infection frequently was transmitted by barbers who used unsanitary razors, so it was termed barber's itch

47. 1- Inflammatory deep type (kerion)
It is the most common clinical presentation
caused primarily by zoophilic dermatophytes
Most patients show solitary plaques or nodules; however, multiple plaques are relatively common
Usually localized on the chin, cheeks, or neck, involvement of the upper lip is rare

48. The characteristic lesion is an inflammatory reddish nodule with pustules and draining sinuses on the surface. Hairs are loose or broken, and depilation is easy
and painless

49. Over time, the surface of the indurated nodule is covered by exudate and crust
This variety of tinea barbae usually is associated with generalized symptoms, such as regional lymphadenopathy, malaise, and fever

50. 2-Noninflammatory superficial type
Caused by anthropophilic dermatophytes
This variety is less common
and resembles bacterial
folliculitis
Typically, erythematous patches show an active border composed of papules, vesicles, and/or crusts. Hairs are broken next to the skin

51. Tinea Unguium and Onychomycosis

52. Tinea unguium is clinically defined as a dermatophyte infection of the nail plate
Onychomycosisincludes all infection of the nail caused by any fungus, including nondermatophytes and yeasts

53. Etiology It accounts for 20 % of all nail disease
Approximately 30 percent of patients with dermatophyte infections on other parts of their body also have tinea unguium
The most common dermatophytes causing tinea unguium worldwide are T. rubrum, T. mentagrophytes ,E. floccosum &Candida

54. Clinically
Characteristically, infected nails coexist with normal-appearing nails
Four types are recognized:
Distal subungual onychomycosis
Proximal subungual onychomycosis
White superficial onychomycosis
Candidal onychomycosis

55. Distal subungual onychomycosis
It is the most common type and starts by invasion of the stratum corneum of the hyponychium and distal nail bed
Infection moves proximally in the nail bed and invades the ventral surface of the nail plate

56. Subungual hyperkeratosis results from a hyperproliferative reaction of the nail bed in response to the infection
Invasion of the nail
plate results in a
progressively
dystrophic nail unit

57. Proximal subungual onychomycosis
It is the least common variant of onychomycosis
It starts by fungal invasion of the stratum corneum of
the proximal nail fold
and subsequently the
nail plate

58. White superficial onychomycosis
Well-delineated opaque "white islands" on the plate
Patches coalesce to involve the entire nail plate. The nail becomes rough, soft and crumbly

59. Sporotrichosis

60. Etiology Caused by Sporothrix schenckii
The organism derives its name from R B Schenck, who first reported the infection in 1898
Sporothrix typically exists as a saprophytic mold on vegetative matter in humid climates worldwide
It is a dimorphic fungus i.e. the organism exhibits mycelial forms at 25°C and a yeast form at 37°C

61. Cutaneous infection often results from a puncture wound involving thorns or other plant matter
Other more unusual reported causes include squirrel bites and trauma induced by liposuction

62. Clinically 1-Lymphocutaneous type It is the most common presentation
Symptoms usually arise within 3 weeks of injury
A subcutaneous nodule develops at the site of inoculation and may ulcerate as the result of central abscess formation
Satellite lesions form along the associated lymphatic chain and lymphadenopathy subsequently develops

64. 2-Fixed (nonlymphatic) type:
scaly, acneform, verrucous or ulcerative nodule that remains localized
Satellite lesions
and
lymphadeno-
pathy do not
occur in this form

65. 3-Disseminated type
Can result in pyelonephritis, orchitis, mastitis, arthritis, synovitis, meningitis or osseous infection

66. Mycetoma
(Madura foot)

67. Etiology
Gill first described the disease in the Madura district of India in 1842
In 1813, Pinoy described the mycetoma produced by actinomycetes (aerobic bacteria) and classified mycetomas as those produced by true fungi (eumycetoma) versus those due to aerobic bacteria (actinomycetoma). Both types have similar clinical findings
Causative agents are implanted subcutaneously, usually after a penetrating injury

68. Filamentous bacteria (actinomycetoma) 60% True fungi (eumycetoma) 40%
Actinomadura madurae
Actinomadura pelletieri
Streptomyces somaliensis
Nocardia brasiliensis
Nocardia otitidis-caviarum
Nocardia asteroides
Dark grain:
Madurella mycetomatis
Madurella grisea
Leptosphaeria senegalensis
Curvularia lunata
Pale grain:
Scedospor. apiospermum
Neotestudina rosatii
Acremonium spp.

69. Clinically
The skin is usually darker and firmer than the surrounding areas
Nodules, abscesses, and fistulae draining a clear viscous or purulent exudate can be seen
Granules of the microorganisms (sulpher granules) may occasionally be seen The most common site is the feet
In advanced cases, destruction of bone within an infected area may be almost complete, and gross deformity may result

71. Lab diagnosis of fungal infections

72. Clinical Material
Patients with suspected dermatophytosis of skin:
any ointments or other local applications present should first be removed with alcohol
Using a blunt scalpel, firmly scrape the lesion, particularly at the advancing border. In cases of vesicular tinea pedis, the tops of any fresh vesicles should be removed as the fungus is often plentiful in the roof of the vesicle

73. In patients with suspected dermatophytosis of nails:
The nail should be pared and scraped using a blunt scalpel until the crumbling white degenerating portion is reached
Any white keratin debris beneath the free edge of the nail should also be collected

74. Up to 30% of suspicious material collected from nail specimens may be negative by either direct microscopy or culture
Repeat collections should always be considered in cases of suspected dermatophytosis with negative laboratory reports

75. Direct Microscopy
Skin Scrapings, nail scrapings and epilated hairs should be examined using 10% KOH

76. Culture
Specimens should be inoculated onto primary isolation media, like Sabouraud's dextrose agar containing cycloheximide and incubated at 26-28C for 4 weeks. The growth of any dermatophyte is significant

77. Wood's lamp examination
It consists of UV light of wavelength above 365nm filtered through glass which contains about 9% nickel oxide
Value: generally of limited usefulness, because most dermatophytes currently seen do not fluoresce

78. May have value in the following situations:
For diagnosing a brown, scaly rash in the scrotum or axilla: erythrasma fluoresces a brilliant coral red, whereas tinea cruris or cutaneous candidal infections do not fluoresce
For diagnosing tinea versicolor, which fluoresces pale yellow to white
For diagnosing tinea capitis caused by two zoophilic Microsporum species that fluoresce blue-green

79. Histopathology

80. PAS stain: Spores & hyphae in the keratin

81. Tinea versico;or: Spaghetti & meat balls