2. Mycotic infections are fungal infection of
animals, including humans.
• Mycotic infections are common and a variety of
environmental and physiological
conditions can contribute to the
development of fungal diseases. • Inhalation
of fungal spores or localized colonization
of the skin may initiate persistent
infections; therefore,
Mycotic infections often start in the lungs
or on the skin.
3. The fungi that cause subcutaneous Mycotic infections
normally reside in soil or on vegetation.
They enter the skin or subcutaneous tissue by traumatic
inoculation with contaminated material.
In general, the lesions become granulomatous
and expand slowly from the area of
implantation to local lymph nodes.
Extension via the lymphatics draining the
lesion is slow except in sporotrichosis. Mycotic
infections are usually confined to the subcutaneous
tissues, but in rare cases they become systemic
and produce life-threatening disease.
4. Morphological Classification
• Moulds : hyphae in form. Eg: ringworm or dermatophytes.
• Yeasts : Single cell that bud to reproduce. Eg: cryptococcus
neoformans.
Yeast like: Form Pseudohyphae. Eg: candida albicans.
• Dimorphic fungi: have both a yeast form ( at human body temp)
and a mold form ( at room temp ) eg: Blastomyces dermatitides.
Classification
• According to pathogenicity
1.Superficial mycoses
2.Mucocutaneous mycoses
3.Subcutaneous mycoses
4.Deep Mycoses / systemic.
5. People are at risk of fungal infections when
they are taking strong antibiotics for a long
period of time because antibiotics kill not only
damaging bacteria, but healthy bacteria as
well.
This alters the balance of
microorganisms in the mouth, vagina,
intestines and other places in the body, and
results in an overgrowth of fungus.
6. Individuals with weakened immune systems
• with HIV/AIDS,
• under steroid treatments, and taking
chemotherapy.
• with diabetes also tend to develop fungal
infections.
• Very young and very old people, also, are
groups at risk.
7. The response to infection with many fungi is the
formation of granulomas.
• Granulomas are produced in the major systemic
fungal diseases, e.g., coccidioidomycosis,
histoplasmosis, and blastomycosis, as well as
several others.
• The cell-mediated immune response is
involved in granuloma formation.
• Activation of the cell-mediated immune
system results in a delayed hypersensitivity
skin test response to certain fungal antigens
injected intradermally.
8. • Acute suppuration( pyogenic response ),
characterized by the presence of neutrophils in the
exudate, also occurs in certain fungal diseases such as
aspergillosis and sporotrichosis.
• Intact skin is an effective host defense
against certain fungi (e.g., Candida, dermatophytes), but
if the skin is damaged, organisms can become
established.
• The normal flora of the skin and mucous
membranes suppress fungi.
• When the normal flora is inhibited, e.g., by
antibiotics, overgrowth of fungi such as C.
albicans can occur
9. Candidiasis *C. albicans, C. tropicalis, C. glabrata, C.
parapsilosis, C. krusei, C. kyfer, C. dubliniensis
Aspergillosis Aspergillus fumigatus
Cryptococcosis Cryptococcus neoformans
Histoplasmosis Histoplasma capsulatum
Blastomycosis Blastomyces dermatitidis
Zygomycosis Orders Mucorales and Entomophthorales
Coccidioidomycosis Coccidioides immitis
Paracoccidiomycosis Paracoccidioides brasiliensis
Penicilliosis Penicillium marneffei
Sporotrichosis Sporothrix schenckii
Geotrichosis Geotrichum candidum
10.
11. CAUSATIVE AGENT-
Yeast like fungus, candida (monilia)
albicans.
Although other species such as
C.tropicalis,
C.parapsilosis,C.stellatoidea &
C.glabrata may also be involved.
12. These species grow rapidly at 25-37◦C.
This microorganism is a relatively common
inhabitant of the oral cavity,
gastrointestinal tract and vagina of
clinically normal persons.
Mere presence of the fungus is not sufficient
to produce the disease. There must be
actual penetration of the tissues.
The disease is said to be the most
OPPORTUNISTIC INFECTION in the world.
Its occurrence has increased remarkably
since the prevalent use of antibiotics,
which destroy the normal inhibitory
bacterial flora & immunosupressive
drugs,particularly corticosteroids and
cytotoxic drugs.
18. Can occur at any age
Especially prone to occur in debilitated or chronically
ill patients.
Oral lesions- soft, white, slightly elevated
plaques mostly on buccal mucosa & tongue, but
also seen on palate,gingiva and floor of the
mouth.
Plaques have often been described as resembling Milk
Curds, consisting of tangled masses of fungal
hyphae with intermingled desquamated
epithelium, keratin, fibrin,necrotic debris,
leukocytes & bacteria.
19. The white plaque can usually be wiped away with
a gauze ,leaving either a relatively normal
appearing mucosa or an erythematous area.
21. Also known as Antibiotic Sore Mouth.
Usually occurs as a sequelae to a course of broad
spectrum antibiotics.
Lesions appear red or erythematous rather than
white.
Only variety of oral candidiasis which is consistently
painful
This lesion comes under the category of erythematous
candidiasis which includes central papillary atrophy
of tongue & cheilocandidiasis.
22.
23. This is ‘Leukoplakia’ type of candidiasis.
Oral lesions consist of firm,white persistent
plaques,usually on lips, tongue & cheeks.
HOMOGENOUS OR SPECKLED
Lesions may persist for period of years.
25. This is a group of different forms of the infection.
In general chronic mucocutaneous candidiasis is
characterized by chronic candidal involvement of
skin, scalp,nails & mucous membranes.
As a group ,the patients exhibit varying abnormalities in
their immune system- impaired cell mediated
immunity, isolated IgA def. & they are usually
resistant to common forms of the treatment.
26.
27. Widespread skin involvement &
granulomatous and horny masses on
the face & scalp.
Mouth is common primary site for
typical white plaques.
Nail involvement also seen.
28. Genetically transmitted condition
characterized by candida infection of the
skin ,scalp,nails & mucous membranes,
classically oral cavity, in association with
either hypoadrenalism (Addison’s disease),
hypoparathyroidism, hypothyroidism, ovarian
insufficiency or diabetes mellitus.
Endocrine manifestations which may be
multiple may not appear clinically for
years.
Enamel hypoplasia commonly seen.
29. Least common form
Exhibit extensive raised crusted sheets
involving the limbs,groin, face, scalp &
shoulders, mouth and nails.
No familial history.
30. Better known as ‘DENTURE SORE MOUTH’.
Diffuse inflammation of the denture bearing
area often occuring with angular chelitis.
Women affected more frequently than men.
Denture related candidiasis may be the most
common form of oral disease.
31.
32. Fragments of plaque material may be smeared on a
microscopic slide, macerated with 20% KOH & examined
for typical hyphae.
Culture media- blood agar, cornmeal agar & Sabouraud’s
Broth –also aid in diagnosis.
Presence of yeast cells & hyphae or mycelia in the
superficial and deeper layers of involved epithelium.
Colonies are creamy,white, smooth with a yeasty odour.
34. PAS positive candidal hyphae invading the
epithelium .
Epithelium may hyperkeratosis and elongated
rete ridges .
Collection of neutrophils in epithelium .
35. REYNOLDS-BRAUDE PHENOMENON-
Rapid method of identifying C.albicans is based on
its ability to form germ tubes within two hours
when incubated in human serum at 37*C.
Id REACTION-
It is a hypersenstivity reaction to candidal
antigen,which manifests as vesicular & papular
rash on the skin of patients with chronic
36. Any kind of clinical material (swab, sputum, etc.) for microscopy or
culture should be examined as quickly as possible, because drying
may impair the viability of yeasts.
Frequently, Sabouraud's dextrose agar is used as a primary
culture medium.
SMEARS-
Detection of yeasts in a clinical specimen should start with direct
microscopic examination of smears from the lesion.
After fixation, one slide is stained by periodic acid Schiff (PAS)
technique.
Advantage: simple and quick
Disadvantage: low sensitivity
37. .
SWAB-
Rubbing a sterile cotton-tipped swab over the lesional
tissue or all surfaces irrespective of the clinical signs is a
useful assay for the presence or absence of Candida.
PAPER POINTS-
C. albicans has been detected previously in the
subgingival flora or in the gingival tissues of PD
abscesses.
An absorbent sterile paper point is inserted to the
depth of the pocket and then transferred to a
transport medium.
Then plated out on appropriate media
39. Estimates of hemoglobin, lymphocyte and
WBC counts, whole blood folate, vitamin B
12 and serum ferritin can be important.
(Scully and Cawson, 1987).
40. Mainly by resolving the predisposing causes.
All candida stains are sensitive to Nystatin but
as it is poorly absorbed from gut,it is not useful
in systemic diseases.
Amphotericin B, 5-fluorocytosine ,
Clotrimazole & Iconazole also used.
