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Molds and Fungi
CRYPTOCCUS NEOFORMANS
Crytoccus neoformans is the cause of the fungal
infection Crypyoccosis. The inhalation of the
Cryptococcus neoformans in particles of dust
contaminated by pigeon feces, therefore, cryptococcosis
is primarily an urban infection. It is most common in
the central and western states. It is most likely to
develop in immunologically compromised persons,
particularly those with Hodgkin’s disease, leukemia,
lymphomas and those receiving immunospuressives.
GEOTRICHUM CANDIDUM
Geotrichum candidum fungi is the cause of the disorder
Geotrichosis, a term applied to several oral, bronchial,
pharyngeal and intestinal disorders. This fungus is
normally found even in healthy persons. Geotrichum
candidum grows in soil and is often found in dairy
products. Geotrichum candidum can cause a
bronchopulmonary disorder with viscous, blood-tinged
sputum and allergic asthmatic reactions similar to
allergic aspergillosis. Geotrichosis occurs most often
in immunosuppressed persons and in diabetics.
ASPERGILLOSIS FUMIGATUS
Aspergillus occurs in four major forms: Aspergilloma,
Aspergillus fumigatus, Aspergillus niger, Aspergillosis
endophthalmitis. Aspergillus is found worldwide, often
in fermenting compost piles and damp hay. It is
transmitted through inhalation of the fungal spores or
the invasion of spores through a wound or other tissue
injury. It is a common laboratory contaminant and is the
most common cause of infections in hospitals.
Aspergillus is normally present in the mouth and sputum.
Aspergillus may cause infection of the ear (otomycosis),
cornea (mycotic keratitis), and prosthetic heart valves
(endocarditis).
ZYGOMYCETES
There are two orders of Zygomycetes that act as
pathogens in humans: the MUCORALES order which contains
the Mucoraceae family of genera – Rhizopus, Mucor, and
Absidia, and the ENTOMOPHTHORALES order. RHIZOPUS, MUCOR,
and ABSIDIA cause mucormycosis infections. Typically,
the transmission of rhinocerebral mucormycosis occurs by
inhalation of fungi found in soil or decaying vegetable
matter. These fungi are found throughout the world. This
fungi then invades the mucous membrane and blood vessel
walls.
TINEA
Tinea is a fugal infection of many different kinds of
the skin infections. The specific type depends on the
characteristic appearance, etiopigic agent and site. The
Tinea fungi feed on the body’s waste products of dead
skin and perspiration. The fungi are highly contagious.
Prevention is largely a matter of cleanliness – washing
all parts of the body with soap and water, especially
hairy areas and body folds, followed with thorough
drying. Transmission may also occur through ingestion,
trauma, and I.V. catherization.
EPIDERMAOPHYTON FLOCCOSUM
A fungal infection of the
skin involving the feet but can cause rash and itching
in other body parts as well. Transmission can occur
directly, through contact with infected lesions or
through contact with contaminated articles, such as
shoes, towels, or shower stalls. This fungus combined
with Candida albicans and Trichophyton cause the Tinea
infection Athlete’s Foot.
TRICHOPHYTON
Trichophyton fungus is the source of
several fungal infections of the skin.
Tinea Corporis – commonly called ringworm. Flat lesions
on the skin at any site except the scalp, bearded skin
or feet. These lesions are dry and scaly or moist and
crusty. As they heal they cause the classic ring-shaped
appearance.
Tinea Unguium
– (Onychomycosis) an infection that
typically starts at the tip of one or more toenails or
fingernails (fingernail infection is less common) and
produces a gradual thickening, discoloration, and
crumbling of the nail eventually destroying the nail
completely.
Tinea Capitis – Characterized by small spreading papules
on the scalp, causing patchy hair loss with scaling.
These lesions may progress to inflamed, pus filled
lesions. This infection is sometimes called Ringworm of
the scalp.
MICROSPORUM FURFUR
Microsporum furfur fungus is of the
Tinea family that is the cause of the chronic,
superficial infection Tinea Versicolor. Tinea Versicolor
typically produces raised or macular, round or oval,
slightly scaly lesions on the upper trunk but may extend
to the lower abdomen, neck, arm, but rarely the face.
These lesions usually are tawny but may range from white
patches in the dark-skinned persons to hyperpigmented
(brown) patches on fair skinned persons. These areas do
not tan when exposed to sunlight. Inflammation, burning
or itching is possible but usually absent.
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Rhinocerebral mucormycosis produces ulceration or
perforation of the nasal septum and necrosis of the
nasal turbinates.
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Pulmonary mucormycosis causes gradual or dudden onset of
chest pain, fever, hemoptyis and friction rub.
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Gastrointestinal mucormycosis often is associated with
manutrition, causes abdominal pain, bloody diarrhea, and
eventually intestinal perforation.
RHIZOPUS Rhizopus is the black mold found on bread. Once Rhizopus
lays down a mat of hyphae on bread it pushes specialized
spore bearing hyphae up in the air. Each spore can
germinate to produce a new mat of hyphae creating lumps
of hyphae spores that look like small black balloons.
SPOROTRIX SCHENCKII Sporotrix schenckii is found throughout the world. It is
found in soil, wood, sphagnum moss and decaying
vegetation. This fungus usually enters through broken
skin, (the pulmonary form through inhalation). Sporotrix
schenckii occurs in three forms:
Cutaneous lymphatic produces skin lesions, usually on
the hands or fingers. Each lesion begins as a small
painless subcutaneous nodule but progresses to
ulcerated, swollen, crusted nodules. Pulmonary sporotrichosis causes a productive cough, lung
cavities and nodules, and the formation of a fungus
ball. It is often associated with sarcoidosis and
tuberculosis.
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