1. The document discusses various types of tinea or dermatophytosis, a fungal infection of the skin, hair, and nails, caused by dermatophyte fungi including Trichophyton, Epidermophyton, and Microsporum genera. 2. It describes the clinical manifestations and treatment of common types of tinea infections such as tinea corporis (ringworm of the body), tinea pedis (athlete's foot), tinea cruris (jock itch), tinea unguium (nail infection), tinea capitis (ringworm of the scalp), and tinea barbae (ringworm of the beard). 3. Laboratory

1. Tinea – The Dermatophytes Dr Kamran Afzal Asst Prof Microbiology

2. Tinea ‘ skin plants’ ‘ ringworm’ ‘ herpes’ by the Greeks ‘ tinea' by the Romans (small insect larvae) Dermatomycosis Dermatophytosis - Cutaneous Fungal Infection Disease of the nails, hair, and/or stratum corneum of the skin caused by fungi

3. Three important genera Trichophyton - Skin, hair, nail Epidermophyton - Skin, nail Microsporum - Skin, hair

4. Clinical Classification Tinea corporis - ringworm infection of the body Tinea pedis - ringworm infection of the foot Tinea cruris - ringworm infection of the groin Tinea unguium - ringworm infection of the nails Tinea capitis - ringworm infection of the head, scalp, eyebrows, eyelashes Tinea favosa - ringworm infection of the scalp Tinea manuum - ringworm infection of the hand Tinea barbae - ringworm infection of the beard

5. 1. Tinea corporis Body ringworm Circular rash Does not fade Can appear on all surfaces Spreads by direct contact

6. CLINICAL MANIFESTATIONS Concentric or ring-like lesions on skin Generally restricted to stratum corneum of the smooth skin In severe cases these are raised and may become inflamed

7. Tinea corporis resolves itself in several months Symptoms result from fungal metabolites such as toxin/allergens

9. 2. Tinea pedis Athlete’s Foot Three causal agents T. rubrum source are people with chronic infections, because fungus not long-lived in squames T. mentagrophytes Epidermophyton floccosum source are long-lived arthrospores, that reside in squames deposited in rugs and carpets (fomites)

10. CLINICAL MANIFESTATIONS Between toes or toe webs (releasing of clear fluid) 4th and 5th toes are most common In one study - 85 % of college students carried a ringworm fungus Soreness and itching of any part of the foot

11. 3. Tinea cruris Jock Itch Ringworm infection of the groin, scrotum and inner thigh Causes of Tinea cruris include T. rubrum T. mentagrophytes E. flocossum

12. CLINICAL MANIFESTATIONS More common in men than women Predisposing factors include persistent perspiration, high humidity, irritation of skin from clothes, such as tight fitting underwear or athletic supporters, pre-existing disease such as diabetes and obesity

13. 4. Tinea unguium Nail Infection Most commonly caused by T. rubrum E. floccosum Trichophyton species Can follow Tinea pedis

14. Nail changes Begins distal  proximal Toes > fingers Thickening Yellowing Onycholysis, crumbling Associated Tinea pedis

15. 5. Tinea capitis Ringworm of the scalp, eyebrows and eyelashes

16. CLINICAL MANIFESTATIONS Caused by species of Microsporum and Trichophyton Fungus grows into hair follicle Tinea capitis is very contagious and can be transmitted by people, animals or objects carrying the fungus It always requires systemic medication - griseofulvin Fungistatic agents are somewhat effective (miconazole, clotrimazole)

17. Alopecia in affected areas Endothrix invasion of hair shaft Using a Wood's lamp on hair Microsporum species tend to fluoresce green Trichophyton species generally do not fluoresce

18. The clinical hallmark is single or multiple patches of hair loss, sometimes with a “black dot” pattern, which may be accompanied by signs of inflammation such as scaling, pustules and itching

19. 6. Tinea favosa Ringworm infection of the scalp (crusty hair)

20. 7. Tinea manuum Ringworm infection of the hand

21. 8. Tinea barbae Ringworm infection of the beard

22. Transmission Close human contact (Direct) Sharing clothes, combs, brushes, towels, bedsheets... (Indirect) Animal-to-human contact (Zoophilic)

23. Pathology Dermatophytes use keratin as a source of nutrition Therefore they infect skin, hair, nails All 3 organisms infect /attack skin Microsporum does not infect nails Epidermophyton does not infect hair, they do not invade underlying non-keratinized tissues

24. Clinical Significance DERMATOPHYTOSES Characterized by Itching, scaling of skin patches that can become inflamed and weeping Infection in different sites may be due to different organisms but is given one name

25. Clinical manifestations Skin: Circular, dry, erythematous, scaly, itchy lesions Hair: Typical lesions, ”kerion”, scarring, “alopecia” Nail: Thickened, deformed, friable, discolored nails, sub-ungual debris accumulation Favus (Tinea favosa)

26. Lab Diagnosis Nail clippings, skin scrapings, hair /follicle Placed in sterile container preferably, or between 2 slides No role for swabs KOH ( 10-25% ) will be added in the lab to dissolve tissue material Lactophenol blue stain to see if fungal hyphae seen

27. For full identification culture on selective media required Sabouraud dextrose agar (SDA) SDA with cycloheximide or chloramphenicol Low pH 5.0 May require 10-14 days for growth Macroscopic and microscopic identification of colonies

28. T. mentagrophytes

29. Treatment Topical Miconazole, clotrimazole, econazole, terbinafine... Oral Griseofulvin Ketaconazole Itraconazole Terbinafine

30. Superficial Mycoses Reddish spots if fair skinned Caused by Malazzesia furfur “ Spaghetti Meatballs” appearance in Lactophenol Cotton Blue stain Tinea versicolor Treatment Ketoconazole, fluconazole, itraconazole

31. QUIZ..

32. Tinea pedis

33. Tinea unguium

34. Tinea corporis

35. Tinea cruris

36. Tinea barbae

37. Tinea corporis