FUNGAL INFECTIONS

1. FUNGAL
INFECTIONS
Dr.T.Arivazhagan
Department of pathology

2. Introduction
• There are over 100,000 fungal species
• In which 150 species are pathogenic
• Mostly they are from environmental sources
• Most of the infections are mild and self limited

3. Growing pattern
Mold:
• Grow as a multicellular filaments
• They are grow and divided at their tips
• Ex - Aspergillus
Yeast:
• Grow as individual cells or in chains
• Round to oval
• Reproduce by budding
• Ex – candida
Most medically important fungi – Dimorphic fungi

4. Hyphae
• It is a long thread like filamentous structure of the fungus
• It is a main mode of vegetative growth

5. Septate Nonseptate Pseudo hyphae
Hyphae divided into Hyphae are not Result from
the cells by cross walls divided by septate incomplete budding
Cells are remain
attached after
the division
Seen in yeast

6. The disease depends on the
1. Virulence
2. Dose
3. Route of infection
4. Immunological status of the host

7. Route of transmission
1. Direct
• From infected host
2. Indirect
• From infected material like skin , hair etc…

8. Fungal infection (mycoses)
1. Superficial
• Inflammatory
• Noninflammatory
2. Cutaneous
3. Subcutaneous
4. Systemic

9. Superficial fungal
infections
• Affect the outer layer of the skin
• Main causes
• Yeast – candida
• Mould – Aspergillus
• Dermatophytes
• Trichophyton - skin , hair ,nails
• Epidermophyton – skin , hair
• Microsporum – skin , nails

10. • Geophilic – Prefer to live in soil
• Anthropophilic – Prefer to infect the humans
• Zoophilic – Prefer to infect the animals

11. Candidiasis
• Yeast form
• C . Albicans
• Infection occurs when normal
commensal flora breach the
skin or mucosal barriers

12. Pathogenesis
• Phenotypic switching
• Virulence factors
• Integrin like proteins
• Several agglutinins
• Enzymes
• Neutrophils , Macrophages,
TH 17 – protect against the
candida infections.

13. Morphology
• Appears as a yeast
• Pseudo hyphae – Important diagnostic clue
• Special stains – Gomori Methanamine silver ,PAS

15. • Oral thrush - Gray white , dirty looking pseudo membrane
composed of matted organisms and inflammatory debris.

16. •Candida esophagitis
• Commonly seen in AIDS patients
• Painful swallowing
• Retrosternal pain
•Candida vaginitis
• Pregnant Women
• Diabetic
• OCP
• Intense itching
• Thick curd like discharge

17. •Cutaneous candidiasis
1. Nail proper –onychomycosis
2. Nail folds – paronychia
3. Hair follicles – folliculitis
•Invasive candidiasis
• Renal abscess
• Myocardial abscess
• Hepatic abscess

18. Aspergillosis
• Molds form
• A. Fumigatous
• Produce allergic bronchopulmonary Aspergillosis
• Produce sinusitis, pneumonia, invasive diseases

19. Pathogenesis
• Transmitted by air borne conidia
• Lung is the major portal of entry
• Produces several virulence factors
• Adhesions
• Antioxidants
• Enzymes
• Toxins

20. Morphology
Colonizing Aspergillosis ( ASPERGILOMA)
• Growth of the fungus in the pulmonary cavity
• Produce fungal balls

21. Invasive Aspergillosis
• Opportunistic infection
• Immunocompromised patients
• Forms fruiting bodies
• Septate filaments
• 5 to 10μm thick
• Branching at acute angles (40degrees)

22. Aspergillus Fruiting bodies

23. Dermatophytosis
•Ringworm
•Fungal infection of the skin
•Red ,itchy , scaly, circular rash

24. Tenia infection
1. T. capitis ( head)
2. T. faciei ( face)
3. T. barbae (beard)
4. T.corporis( body)
5. T.manus ( hand)
6. T.cruris ( groin)
7. T.pedis (foot)

25. Subcutaneous fungal infection
• It involve the deeper layer of the skin
• Dermis, subcutaneous tissue, muscle, fascia
• Examples :
• Mycetoma
• Chromoblastomycosis
• Sporotrichosis