1. CLINICAL MYCOLOGY 2
INNOCENT AFEKE
UHAS

2. SUPERFICAL /CUTANEOUS MYCOSES (DERMATOPHYTES)

3. Infections strictly confined to keratinized epidermis (skin, hair, nails) are called dermatophytoses e.g. ringworm , tinea and athlete’s foot
Source of infection:
Anthropophilic: Associated with humans only. Person -to-person transmission through contaminated objects (comb, hat, hospital beddings etc.)
Zoophilic: Associated with animals. Direct transmission to humans by close contact with animals (pets)
Geophilic : Usually found in soil. Transmitted to humans by direct exposure (occupational hazards: gardeners & farmers)

4. (MET) Have 3 Genera of Dermatophytes of clinical importance (MET)
Microsporum
Epidermophyton
Trichophyton
(MET)

5. Microsporum Lab. Culture and Microscopy 13 species are known
Affects Hair and Skin
Culture shows cottony aerial hyphae
Microscopy :thick wall, spindle shape, multicellular
Microsporum canis:

6. Epidermophyton floccosum
Affects Nails and Skin
Culture: cottony , range of colours
Microscopy: Bifurcated hyphae with multiple, smooth, club shaped macroconidia (2-4 cells)
Lab culture and Microscopy

7. Trichophyton 19 species are known Affects Hair, Skin and Nails
Lab Culture and Microscopy

8. Superficial mycoses
Pityriasis versicolor – pigmented lesion on torso (trunk). - Tinea nigra – gray to black macular lesion on palms. - Black piedra – dark gritty deposits on hair. - White piedra – soft whitish granules along hair shaft.

9. Tinea infections: Red, scaly or blister-like lesions; often a raised red ring; “ringworm
Tinea pedis
Tinea corporis
Tinea capitis
Tinea favosa
Tinea barbae
Tinea cruris
Tinea unguium

10. Samples for Lab Investigation
Skin scrapings for culture &microscopy
Cutting of part of nail
Shave hair (at the edge not middle)
Comb culture

12. Zig-lock bag (envelop) ; send to lab
Culture of comb

13. THERAPY FOR DERMATOPHYTES
Clotrimazole
Miconazole
Ketoconazole
Itraconazole
Griseofulvin
Tinactin
Terbinafine

14. Subcutaneous Mycoses

15. Infections beneath the skin; Hyphae or spores in wounds
More serious than cutaneous mycoses
-Sporothrix schenkii
-Soil organism
-mode of transmission is by inoculation through abrasive skin
Gardeners=ulcers on hands or foot
Chronic infection
May accompany with secondary infection
Treatment is slow

16. Subcutaneous Mycosis: MYCETOMA
-It is a chronic infection of the skin, subcutaneous tissue and sometimes bone
Mycetoma may be due to several fungi or actinomycetes (actinomycetoma
Actinomycetes are bacteria producing filaments like fungi
The organism is inoculated into the skin by a minor injury, for example, a cut with a thorn when barefoot

17. CANDIDIASIS Vaginitis and thrush are initiated by:
Thrush & Vaginal Candidiasis
Mucosal normal microbiota suppresses the growth of Candida albicans
Vaginitis and thrush are initiated by:
-Antibiotics eliminate normal microbiota
-pH changes
Infants who may not have their normal microbiota established=thrush

18. SYSTEMIC OR DISSEMINATED MYCOSES

19. Systemic Candidiasis
Hematogenous dissemination from a localized infection
Spreads to organs like
-Kidney
-Spleen
-Lung
-Liver
Fungal Blood Culture may be positive
Culture of surgical tissue sample may be positive (invasive procedure)
Liver infected with Candida/Culture on medium

20. Systemic Mycoses Disseminated from Respiratory System
HISTOPLASMOSIS (Histoplasma capsulatum)
Resembles tuberculosis
Vague symptoms
Transmission
-Airborne conidia
-Bats: Carry fungus in feces
-Birds: Feces
May affect all organs
Dimorphic fungi
Yeast lives within macrophages and multiplies
In USA , cases mainly from Mississippi river and Ohio river states

21. Treatment (intravenous)
Diagnostic
Blood test—Antibody titre
X-ray
Treatment (intravenous)
-Amphotericin B
-Itraconazole

22. (2) COCCIDIOIDOMYCOSIS
Two species: Coccidioides immitis & Coccidioides posadasii
Arthrospores in dry alkaline soils (found in specific geographic areas)
Transmitted by wind
Dimorphic fungi
Disease called Valley Fever
Symptoms
-Chest pain
-Fever
-Cough
-Extreme fatigue

23. People at risk Immunosuppressed Patients– -organ transplant -lymphoma
-HIV+/AIDS
-adrenal corticosteroid therapy
-diabetes
-3rd trimester pregnancy
In normal individuals;
-Most infections are asymptomatic
-Most recover in a few weeks

24. Diagnostic
Identification of spherules in tissues
C. Immitis spherule in lung tissue
Macroscopy &Microscopy diagnosis of C. immitis in Brain tissue

25. (3) BLASTOMYCOSIS : Blastomyces dermatitidis
Spores found in soil in Mississippi Valley (geographically specific)
The main route of infection is by inhalation of spores
Dimorphic fungus
Most infections are asymptomatic
Begins at lungs and spreads
The disease may disseminate into the skin, bones, or urogenital tract
Major symptoms in humans include loss of weight, fever, cough, and bloody sputum and chest pains.
Diagnostic
-Isolation of organism from pus and biopsies
Treatment
-Amphotericin B

26. Opportunistic Mycosis

27. (1) PNEUMOCYSTIS PNEUMONIA : Pneumocystis carinii
Leading cause of death in AIDS patients
Present in healthy lungs (Normal flora)
1993-Indicator of AIDS
(2) Other respiratory opportunistic fungi
Aspergillus fumigatus
Aspergillus spp.-present in decaying vegetation
Rhizopus spp.
Mucor spp.

28. (3) Cryptococcosis: Cryptococcus Neoformans
Causes Yeast Meningitis in humans
Cryptococcosis in humans usually begins as a primary infection of the lungs.
Most of the cryptococcal infections occur from inhalation of the fungi along with the dust from areas enriched with pigeons manure
There are no visible early symptoms may include cough, chest pain, weight loss, fever or dizziness.
The disease may be in the lungs, mucous membranes, bones, and joints, with no organ or tissue of the body exempt.
Lab Diagnosis:
-Identification of yeast in CSF and other
tissue fluids
-Culture and biochemical test

29. FUNGAL DISEASES OF THE DIGESTIVE SYSTEM

30. Mycotoxins: Fungal Toxins
Ergot poisoning
Claviceps purpurea
Infects Grain Crops
Ergotism: Disease caused by ingestion of contaminated grains
Causes hallucination
The chemical responsible for the hallucinations is actually LSD! lysergic acid
Another ergot derivative may cause spontaneous abortions
The history of ergot in small town “The day of St Anthony's Fire"

31. (b) Aflatoxin poisoning
Aflatoxin is a naturally occurring mycotoxin produced by two types of mold Aspergillus flavus and Aspergillus parasiticus
Peanuts and cottonseeds
Acute intoxication
-Liver damage
Chronic intoxication
-Liver cancer
-Depending on the levels, the toxins can severely affect the liver and they are a known human carcinogen