1. PRESENTATION TOPIC:
BASIC MYCOLOGY
PRESENTED BY:
 SAEEDA ASHRAF
 HOOR UL AIN ROUNAQ
 SADIA WASI
 FATIMA KHAN
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2. TOPICS :
1. STRUCTURE AND
GROWT OF
FUNGI.
2. PATHOGENESIS.
3. FINGAL TOXIN
AND ALLERGIN.
4. LABORATORY
DIAGNOSIS.
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3. BASIC MYCOLOGY
• Several fungi are thermally
dimorphic.
• Most are obligate aerobes.
• Some are facultative anerobes.
• Most require pre-formed organic
source of carbon.
• Natural habitat: environment.
• Fungi imperfecti: donot form
spores.
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4. STRUCTURE OF FUNGI
contain
ergosterol
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5. TWO TYPES OF FUNGI
YEAST
• Grow as single cell.
MOLD
• Grow as long filament.
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6. FUNGAL SPORES
•
ASEXUAL SPORES SEXUAL SPORES
Sporangiospores Zygospore
Conidiospore Ascospore
Arthrospores Basidiospore
Blastoconidium
Chlamydospore
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7. ASEXUAL SPORES
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8. SEXUAL SPORES
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9. PATHOGENESIS:
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certain systemic fungi infection ,
such as Histoplasma & Coccidioides
Cell mediated response involved in
granuloma formation
Infection with Aspergillus,
Mucor & Sporothrix
pyogenic response (composed
of neutrophils).

10. DELAYED HYPERSENSITIVITY TEST
SKIN TEST
Fungal antigen inject intradermally.
POSITIVE SKIN TEST
Exposure to fungal antigen.
Not show current infection may expose in past.
NEGATIVE SKIN TEST
Makes the diagnosis unlikely unless patient is
immunocompromised.
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11. HOST DEFENCE:
HOST DEFRNCE FUNCTION
1.Intact skin Effective against candida,
dermatophytes
2. Fatty acid in skin Inhibit dermatophytes growth
3. Hormone associated skin changes at
puberty
Limit ringworm of the scalp caused by
trichophyton.
4. Normal flora of skin and mucous
membrane
Suppress fungi.
IN RESPIRATORY TRACT:
5. Mucous membrane of nasopharynx
Trap inhaled fungal spores.
6. Circulating IgG and IgM They protect from disease
7. Cell mediated immune response Protect against fungal infection.
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12. FUNGAL TOXIN AND ALLERGINS
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FUNGAL DISEASES
MYCOTOXICOSES
Caused by ingested toxins
ALLERGIES
To fungal spores

13. MYCOTOXICOSES
• It is a disease caused by a natural toxin produced by a fungus.
• Amanitin and phalloidin (most potent hepatotoxin).
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TOXIN PRODUCED BY TOXICITY AND ITS
ADVERSE EFFECT
1. Amanitin poisonous mushroom:
Amanita phalloides.
Its ability to inhibit
cellular RNA polymerase,
which prevent mRNA
synthesis.
ergotism Caused by mold Claviceps
purpura, which infect
grains and produces
alkaloids.
Pronounced vascular and
neurological effects.
aflatoxin Aspergillus flavus
Ingested with spoiled
grains and peanuts.
Liver damage and tumor
in animals
Hepatic carcinoma in
humans.

14. FUNGAL ALLERGINS
thisiscaused by igE immediatehypersensitivityresponsetofungalspores
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FACTORS REACTION
1. Aspergillus Asthmatic reaction.
Eosinophilia.
“ wheal and flare ” skin
test rection.
2. Ingestion of peanuts
& grains contaminated
with Aspergillus flavus
liver cancer due to
presence of aflatoxin.
3. Aflatoxin epoxide mutation in p53 gene
loss of p53 tumor
suppressor protein.

15. 1.Direct Microscopic
examination :
 Wet preparation uses
KOH or NaOH as clearing
agent.
 Calcofluor white stain
 -shows fungal elements
in exudats & small skin
scales under fluorescent
microscope.
 Nigrosin or India Ink.
 Wright stain or Giemsa
stain.
A- calcoflour B- nigrosin
white stain stain

16. 2. Culture
 slow growers.
 Medium .
 Sabouraud Dextrose Agar.
3.DNA probe test:
- identify colonies growing in
culture at an earlier stage of
growth
- available for
coccidioides,histoplasmas,blast
omyces, cryptococcus
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Sabouraud Dextrose Agar

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• 4.Immunologic:
 for detection of antigen or
antibody
 complement-fixation,
Agglutination, Precipitin test
 useful only for systemic &
opportunistic mycoses
 * C-F is freq. used in
suspected cases of
coccidiodomycoses,
blastomycoses,
histoplasmosis

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