Pharmacy Clinic
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Fungal Infections
Fungi
Introduction:
The science of fungi is called mycology and it discuss the Kingdom Fungi which includes
some of the most important organisms, both in terms of their ecological and economic
roles.
By breaking down dead organic material, they continue the cycle of nutrients through
ecosystems(النظم البيئية).
Ecosystems collapsed without fungi to decompose dead organisms, fallen leaves, feces,
and other organic materials, by secreting enzymes that break down organic molecules
and absorb smaller nutrients, thus recycling vital chemical elements back to the
environment. In addition, most vascular plants could not grow without the symbiotic
(متكافل) fungi, that inhibit their roots and supply essential nutrients. Other fungi provide
numerous drugs (such as penicillin and other antibiotics), foods like mushrooms, and the
bubbles in bread.
Fungi also cause a number of plant and animal diseases: in humans, athlete's foot,
candidosis, cryptococcosis and several more serious diseases are caused by fungi.
Because fungi are more chemically and genetically similar to animals than other
organisms, this makes fungal diseases very difficult to treat.
Fungi are a separate part of the microbial world. They are microorganisms that grow
either as yeasts(unicellular, non filamentous) or molds(multicellular, filamentous). Fungi
found mostly in the soil, many are also part of the normal gastrointestinal and skin flora
in humans and animals.
Structure of fungi:
The body of fungi is a netlike mass of filaments called hyphae. Hyphae is a tubular
extensions of spores and branch repeatedly to form the network called mycelium.
The wall of fungi differ from cellulose wall of plants, itis composed of chitin, which is a
strong, flexible nitrogen-containing polysaccharide. The filamentous structure of mycelium
provides a wide surface area for the absorption of materials.
Most fungi are nonmobile organisms; they cannot run , swim, or fly in search of food. But
a mycelium makes up for the lack of mobility by extending the tips of its hyphae into new
target.
Ecological Importance of Fungi:
Fungi and bacteria are the principal decomposers that keep ecosystem stocked with the
inorganic nutrient for plant growth.
Without these decomposers the organic materials, carbon, nitrogen, and other elements
are no longer available as a new raw materials for new generations of life. Imagine what
would become of a forest if its decomposers rested for even a few years. Leaves, feces,
and dead animals would remain unchanged on the forest floor. Plants and animals they
feed would starve because elements taken from the soil would not be returned . Gradually
the forest would die. This is the fate for all ecosystems without decomposers.
Example of these decomposers, saprophytic fungi, decomposes polysaccharides and
proteins. Other example, Mycorrhizae, it means fungus roots and 90% of tree species
have Mycorrhizae. Mycorrhizae are important in natural ecosystems and agriculture. Plant
generally do not grow as well if they are deprived(منع) of their Mycorrhizae. Mycorrhizae
decompose materials and allow trees to absorb materials very well.
Commercial Uses of Fungi:
Most of us have eaten mushrooms, mushrooms are not only fungi people eat, there are
many other types of fungi eaten by some peoples.
The yeast Sacchromyces cerevisiae is a tiny yeast cells, available as many strains baker’s
yeast and brewer’s yeast
(خميرة البيرة), which is very active metabolically, when added to dough, the metabolism of the
cell produces carbon dioxide gas that makes bread rise.
Sacchromyces is a facultative anaerobe that ferments sugars to alcohol when forced to
live without oxygen.
The pharmaceutical industry grows fungi to produce antibiotics. Many fungi secrete
antibiotics as weapons against bacteria that may be attacking the fungus or competing
with it for food. Example, the penicillium fungi that secrete penicillin
Fungal diseases:
Any fungal infection is called mycoses. Mycoses are generally chronic infections because
fungi grows slowly. Mycoses are divided into five groups according to the level of infected
tissue and mode of entry into the host. They are classified as:
Systemic, Cutaneous, Subcutaneous, Superficial, or Opportunistic.
Systemic mycoses
Are fungal infections deep within the body, they can affect many tissues and organisms
in the body. deep mycoses usually caused by saprophytic fungi that live in the soil.
Inhalation of spores is the route of transmission; these infections typically begin in the
lungs and then spread to other body tissues. They are not contagious from animal to
human or from human to human. Two systemic mycoses, histoplasmosis and
coccidioidomycosis.
Subcutaneous mycoses
Infection beneath the skin and are caused by saprophytic fungi, the infection
transmitted directly from soil to puncture or open wounds. These are more serious than
Cutaneous mycoses because they can penetrate the skin.
Maduromycosis caused by the fungus Allescheria boydii. Maduromycosis may be called a
mycetoma, or fungal tumor. It destroys subcutaneous tissues and progresses slowly.
The treatment of this problems is difficult.
Nocardia is a mold like bacteria and called actinomycete mycetoma.
Cutaneous mycoses:
Infect only the epidermis, hair, and nails (dermatomycoses).The later secrete keratinase,
an enzyme that degrades keratin. Keratin is a protein found in hair, nails, and skin.
Infection is transmitted from human to human and from animal to animal by direct
contact.
Infections of this type include tineas or ringworms. Tineas include capitis, ring worm of
the scalp and common among elementary school children, tinea cruris, ringworm of the
feet, or athlete’s foot, is known as tinea pedis, and tinea corporis.
Three types of fungi involved in this type:
-Trichophyton: infect hair, skin, or nails and nails.
-Microsporum involve the hair and skin only
-Epidermophyton affect only skin and nails.
Superficial mycoses
Localized along hair shafts and in superficial(surface)epidermal cells, these are prevalent
in tropical climates.
Opportunistic mycoses
The fungi that are responsible for the recent increase in mycotic infections are those
causing opportunistic infections. These organisms include Candida species, Cryptococcus
neoformans, Aspergillus species, Fusarium species, Coccidioides immitis, and Histoplasma
capsulatum. Persons at high risk for opportunistic fungal infections are those with HIV
infection or AIDS, those who have undergone bone marrow or organ transplants, those
receiving chemotherapy for cancer, and others who have had debilitating illness, severe
injuries, prolonged hospitalization, or long-term treatment with corticosteroid or
antibacterial drugs. Opportunistic mycoses is generally harmless in its normal
habitat but can become pathogenic in a host who is seriously traumatized or who is
under treatment with antibiotics, or whose immune system is suppressed by drugs or by
immune disorder.
Mucomycoses
Is an opportunistic mycoses caused by Rhizopus and mucor; the infection occurs mostly
in patients with ketoacidosis resulting from diabetes mellitus, leukemia, or taking
immunosuppressive drugs.
Asperigillus
Is also an opportunistic mycoses; it is caused by aspergillus. This disease occurs in
persons who experience lung diseases or cancer and have inhaled aspergillus.
Candidiasis
Is the most frequently caused by Candida Albicans and may occur as vulvovaginal
candidiasis during pregnancy.
Thrush
Is amucocutaneous candidiasis, is an inflammation of the mouth and throat; it
frequently occurs in newborns.
Pathogenesis of Infection
Fungal infection may be acquired from both exogenous and endogenous sources.
*Endogenous infection: Pityrosporum obiculare is the only normal flora. Infection with
these yeast organisms develop from patient’s own normal flora, and when host
resistance is failed or reduced these fungi grow up and induce the infection. Many drugs
like immunosuppressant, excess heat, oral contraceptives, pregnancy, diabetics,
malnutrition facilitate the growth of these organisms. Systemic candidal infections occur in
the immunocompromized host when the organism colonizing the patient’s skin or GI tract
is hematogenously spread through out the body.
*Exogenous infection: occurs when the fungi acquired from the environmental sources.
Introduction:
The science of fungi is called mycology and it discuss the Kingdom Fungi which includes
some of the most important organisms, both in terms of their ecological and economic
roles.
By breaking down dead organic material, they continue the cycle of nutrients through
ecosystems(النظم البيئية).
Ecosystems collapsed without fungi to decompose dead organisms, fallen leaves, feces,
and other organic materials, by secreting enzymes that break down organic molecules
and absorb smaller nutrients, thus recycling vital chemical elements back to the
environment. In addition, most vascular plants could not grow without the symbiotic
(متكافل) fungi, that inhibit their roots and supply essential nutrients. Other fungi provide
numerous drugs (such as penicillin and other antibiotics), foods like mushrooms, and the
bubbles in bread.
Fungi also cause a number of plant and animal diseases: in humans, athlete's foot,
candidosis, cryptococcosis and several more serious diseases are caused by fungi.
Because fungi are more chemically and genetically similar to animals than other
organisms, this makes fungal diseases very difficult to treat.
Fungi are a separate part of the microbial world. They are microorganisms that grow
either as yeasts(unicellular, non filamentous) or molds(multicellular, filamentous). Fungi
found mostly in the soil, many are also part of the normal gastrointestinal and skin flora
in humans and animals.
Structure of fungi:
The body of fungi is a netlike mass of filaments called hyphae. Hyphae is a tubular
extensions of spores and branch repeatedly to form the network called mycelium.
The wall of fungi differ from cellulose wall of plants, itis composed of chitin, which is a
strong, flexible nitrogen-containing polysaccharide. The filamentous structure of mycelium
provides a wide surface area for the absorption of materials.
Most fungi are nonmobile organisms; they cannot run , swim, or fly in search of food. But
a mycelium makes up for the lack of mobility by extending the tips of its hyphae into new
target.
Ecological Importance of Fungi:
Fungi and bacteria are the principal decomposers that keep ecosystem stocked with the
inorganic nutrient for plant growth.
Without these decomposers the organic materials, carbon, nitrogen, and other elements
are no longer available as a new raw materials for new generations of life. Imagine what
would become of a forest if its decomposers rested for even a few years. Leaves, feces,
and dead animals would remain unchanged on the forest floor. Plants and animals they
feed would starve because elements taken from the soil would not be returned . Gradually
the forest would die. This is the fate for all ecosystems without decomposers.
Example of these decomposers, saprophytic fungi, decomposes polysaccharides and
proteins. Other example, Mycorrhizae, it means fungus roots and 90% of tree species
have Mycorrhizae. Mycorrhizae are important in natural ecosystems and agriculture. Plant
generally do not grow as well if they are deprived(منع) of their Mycorrhizae. Mycorrhizae
decompose materials and allow trees to absorb materials very well.
Commercial Uses of Fungi:
Most of us have eaten mushrooms, mushrooms are not only fungi people eat, there are
many other types of fungi eaten by some peoples.
The yeast Sacchromyces cerevisiae is a tiny yeast cells, available as many strains baker’s
yeast and brewer’s yeast
(خميرة البيرة), which is very active metabolically, when added to dough, the metabolism of the
cell produces carbon dioxide gas that makes bread rise.
Sacchromyces is a facultative anaerobe that ferments sugars to alcohol when forced to
live without oxygen.
The pharmaceutical industry grows fungi to produce antibiotics. Many fungi secrete
antibiotics as weapons against bacteria that may be attacking the fungus or competing
with it for food. Example, the penicillium fungi that secrete penicillin
Fungal diseases:
Any fungal infection is called mycoses. Mycoses are generally chronic infections because
fungi grows slowly. Mycoses are divided into five groups according to the level of infected
tissue and mode of entry into the host. They are classified as:
Systemic, Cutaneous, Subcutaneous, Superficial, or Opportunistic.
Systemic mycoses
Are fungal infections deep within the body, they can affect many tissues and organisms
in the body. deep mycoses usually caused by saprophytic fungi that live in the soil.
Inhalation of spores is the route of transmission; these infections typically begin in the
lungs and then spread to other body tissues. They are not contagious from animal to
human or from human to human. Two systemic mycoses, histoplasmosis and
coccidioidomycosis.
Subcutaneous mycoses
Infection beneath the skin and are caused by saprophytic fungi, the infection
transmitted directly from soil to puncture or open wounds. These are more serious than
Cutaneous mycoses because they can penetrate the skin.
Maduromycosis caused by the fungus Allescheria boydii. Maduromycosis may be called a
mycetoma, or fungal tumor. It destroys subcutaneous tissues and progresses slowly.
The treatment of this problems is difficult.
Nocardia is a mold like bacteria and called actinomycete mycetoma.
Cutaneous mycoses:
Infect only the epidermis, hair, and nails (dermatomycoses).The later secrete keratinase,
an enzyme that degrades keratin. Keratin is a protein found in hair, nails, and skin.
Infection is transmitted from human to human and from animal to animal by direct
contact.
Infections of this type include tineas or ringworms. Tineas include capitis, ring worm of
the scalp and common among elementary school children, tinea cruris, ringworm of the
feet, or athlete’s foot, is known as tinea pedis, and tinea corporis.
Three types of fungi involved in this type:
-Trichophyton: infect hair, skin, or nails and nails.
-Microsporum involve the hair and skin only
-Epidermophyton affect only skin and nails.
Superficial mycoses
Localized along hair shafts and in superficial(surface)epidermal cells, these are prevalent
in tropical climates.
Opportunistic mycoses
The fungi that are responsible for the recent increase in mycotic infections are those
causing opportunistic infections. These organisms include Candida species, Cryptococcus
neoformans, Aspergillus species, Fusarium species, Coccidioides immitis, and Histoplasma
capsulatum. Persons at high risk for opportunistic fungal infections are those with HIV
infection or AIDS, those who have undergone bone marrow or organ transplants, those
receiving chemotherapy for cancer, and others who have had debilitating illness, severe
injuries, prolonged hospitalization, or long-term treatment with corticosteroid or
antibacterial drugs. Opportunistic mycoses is generally harmless in its normal
habitat but can become pathogenic in a host who is seriously traumatized or who is
under treatment with antibiotics, or whose immune system is suppressed by drugs or by
immune disorder.
Mucomycoses
Is an opportunistic mycoses caused by Rhizopus and mucor; the infection occurs mostly
in patients with ketoacidosis resulting from diabetes mellitus, leukemia, or taking
immunosuppressive drugs.
Asperigillus
Is also an opportunistic mycoses; it is caused by aspergillus. This disease occurs in
persons who experience lung diseases or cancer and have inhaled aspergillus.
Candidiasis
Is the most frequently caused by Candida Albicans and may occur as vulvovaginal
candidiasis during pregnancy.
Thrush
Is amucocutaneous candidiasis, is an inflammation of the mouth and throat; it
frequently occurs in newborns.
Pathogenesis of Infection
Fungal infection may be acquired from both exogenous and endogenous sources.
*Endogenous infection: Pityrosporum obiculare is the only normal flora. Infection with
these yeast organisms develop from patient’s own normal flora, and when host
resistance is failed or reduced these fungi grow up and induce the infection. Many drugs
like immunosuppressant, excess heat, oral contraceptives, pregnancy, diabetics,
malnutrition facilitate the growth of these organisms. Systemic candidal infections occur in
the immunocompromized host when the organism colonizing the patient’s skin or GI tract
is hematogenously spread through out the body.
*Exogenous infection: occurs when the fungi acquired from the environmental sources.