4. INTRODUCTION TO FUNGIINTRODUCTION TO FUNGI
•They have a dense rigid cell wall made of glucan and chitin.
•Their cell membrane contains sterols (ergosterol), making them
similar enough to human cell membranes to have negative
implications for the membrane destroying properties of antifungal
drugs.
•Fungi are eukaryotic, non-motile, and usually
aerobic.
• They can exist as parasites or free living
organisms and need organic sources of
nourishment.
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5. Yeasts – Round/oval, unicellular, and reproduce via budding
Molds – Long, floppy, fluffy colonies that microscopically can be
seen as long tubular structures called hyphae and reproduce by
forming spore-forming structures at the end of hyphae called
conidia.
Dimorphs – Most medically important, can change from yeast
to mold and back, and grow in environment as molds and in
humans as yeast.
Fungi come in many forms but only
three are of our interest as they may
cause disease in human being:
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6. Types of Fungal InfectionsTypes of Fungal Infections
Fungal infections in children are broadly classified
into three types:
I. Superficial/cutaneous – present on skin, hair, nails
II. Subcutaneous – infection in tissues under the skin
III. Systemic – they are of two types:
1. True Pathogens – Which have the ability to
cause disease in healthy host
2. Opportunists – Which cause disease
exclusively in immunocompromised individuals
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7. Levels of Invasion by Fungal PathogensLevels of Invasion by Fungal Pathogens
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8. Superficial fungal infectionsSuperficial fungal infections
Some of the types of superficial fungal infections
that occur frequently in children are:
Candidiasis
Candida diaper rash
Tinea infection
◦ Tinea capitis
◦ Tinea corporis
◦ Tinea pedis
◦ Tinea versicolor
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9. CANDIDIASISCANDIDIASIS
Candidiasis occurs mostly as a superficial
infection of the mucous membrane or skin but
the infection can involve deeper structures (e.g.
oesophagus, lungs) in severely debilitated or
immunosuppressed persons.
It is also called oral thrush.
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10. Appears as white patches known as “plaques”
If the surface of the plaque is scraped away, a sore and reddened
area will be seen underneath, which may sometimes bleed.
Occurs most commonly in babies,
particularly in the first few weeks of life.
Outbreaks of thrush in older children may also be the result of an
increased use of antibiotics and steroids, which disturbs the
balance of microbes in the mouth.
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11. Stratified squamous epithelium of the oral mucosa forms a
continuous surface that protects the underlying tissues and
functions as an impervious, mechanical barrier.
The protection so provided is dependent on the degree of
keratinization and the continuous desquamation or shedding of
epithelial cells.
The commensal flora regulates yeast numbers by inhibiting the
adherence of yeasts to oral surfaces by competing for sites of
adherence as well as for the available nutrients.
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12. Types of Oral Candidiasis
◦ Acute Candidiasis
Pseudomembranous type
Atrophic type
◦ Chronic Candidiasis
Atrophic type
Hypertrophic type
Candida-associated angular chelitis
◦ Systemic Candidiasis
Candidal meningitis
Candidal endocarditis
Candidal septicaemia
◦ Mucocutaneous candidiasis
Localised type
Familial type
Syndrome associated
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13. Acute pseudomembranous CandidiasisAcute pseudomembranous Candidiasis
It is commonly known as “oral thrush” and it appears as a thick,
white soft and friable plaque (pseudomembrane) on the oral
mucosa
The plaque can be easily wiped off by gentle scraping, which leaves
an erythematous, raw, bleeding surface in the affected area.
The lesions may occour at any mucosal site
They vary in size from small drop like areas to confluent plaques
covering a wide suface
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14. •The plaque consists of fungal organisms, keratotic debris,
inflammatory cells, desquamated epithelial cells and fibrin etc.
•Oral thrush commonly occurs among children, debilitated elderly
persons and AIDS patients
•In neonates, the diseases is contracted from birth canal of an
infected mother
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15. Acute Atrophic CandidiasisAcute Atrophic Candidiasis
It occurs when the pseudomembranous covering of oral thrush is
lost.
The lesion prevents a generalised red, painful area over the
mucosa, which often causes tenderness, dysphagia and burning
sensation etc. The condition is commonly seen on the dorsum of
the tongue in patients receiving long term antibiotic or steroid
therapy
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16. Candida-Associated Angular ChelitisCandida-Associated Angular Chelitis
An important form of chronic atrophic candidiasis is “angular
cheilitis”. It occurs at the angle of the mouth among persons having
deep commissural folds secondary to over closure of mouth.
The infection starts due to the colonization fungi in the skin folds
following deposition of saliva due to repeated lip-licking
• Clinically the patients often have soreness,
erythema and fissuring at the corner of the
mouth. In some cases the defect can extend
over the adjoining skin surfaces
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17. It can occur among persons with lip-licking habits,
denture wearing or deficiency of riboflavin, vitamin B-12
and folic acid deficiency etc.
Under favourable conditions (vitamin deficiency,
malnutrition and antibiotic therapy etc.) lesions similar to
angular chelitis could be produced by other organisms
like staphylococcus aureus or streptococcus-β
hemolyticus etc
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18. Chronic Atrophic CandidiasisChronic Atrophic Candidiasis
This form of candidiasis is commonly seen in palatal mucosa of the
denture wearing elderly persons
The condition is more often seen in females than males
The lesion clinically appears as a bright red, erythematous, velvety
areas with little keratinization
It is regarded as secondary candidal infection of oral tissues
modified by continous wearing of ill-fitting dentures and associated
poor oral hygiene
Most of the lesions of chronic atrophic candidiasis are clinically
asymptomatic
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19. Chronic Hyperplastic CandidiasisChronic Hyperplastic Candidiasis
It appears as a slightly elevated, indurated, persistent, white plaque
or patch on the oral mucosa that often resembles oral leukoplakia.
/
The lesions could be bilateral and are mostly seen on the buccal
mucosa near the commisure. Some lesions may also develop over
the tongue or palate etc.
The patchy areas are of irregular thickness and density and they
have a rough, nodular surface
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20. These lesions cannot be removed by scraping and in some cases
there may be presence of erythematous areas within the patch
Development of chronic hyperplastic candidiasis is often favoured
by certain conditions like smoking, denture wearing and occlusal
friction.
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21. Localised Mucocutaneous CandidiasisLocalised Mucocutaneous Candidiasis
This is characterised by long standing and
persistent candidal infections in the oral cavity,
skin, nails and vaginal mucosa, etc.
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22. Familial Mucocutaneous CandidiasisFamilial Mucocutaneous Candidiasis
It is believed to be transmitted genetically as autosomal
recessive trait and most of the patients are mildly
affected.
Syndrome Associated CandidiasisSyndrome Associated Candidiasis
Several candidiasis (both acute and chronic variety) are well
recognised opportunistic infections in immunosuppressed
patients, particularly those suffering from AIDS.
Depressed cell-mediated immunity is believed to be the
cause for development of these lesions
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23. Candidiasis Endocrinopathy SyndromeCandidiasis Endocrinopathy Syndrome
Tranurring mostly in smitted as autosamal recessive trait
Chronic oral candidiasis occurring mostly in second
decade of life
Hyperparathyroidism, Addison’s disease, diabetes mellitus
and hypothyroidism
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24. Treatment
Suspensions of nystatin, held in contact with the oral
lesions.
Other drugs of value are clotrimazole, amphotericin B and
miconazole.
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25. Candida Diaper RashCandida Diaper Rash
It is sometimes called napkin dermatitis, a rash which occurs
in the buttocks. Nappy rash will occur when the skin is
sensitive and there is a presence of a trigger factor which
includes prolonged exposure to urine
It tends to be in the deepest part of the creases in the groin
and buttocks. The rash is usually red with a clearly defined
border and consists of small red spots close to the large
patches
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26. Any diaper rash that lasts for 3 days or longer may be
candidiasis. A Candida diaper rash can be accompanied
by Candida infection of the mouth (thrush).
A breastfeeding infant with a thrush infection may
inadvertently infect the mother’s nipple/areola area. If such an
infection is suspected, simple topical medications may be
prescribed by her doctor.
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27. Tinea InfectionTinea Infection
It is called “ringworm” because the infection may
produce ring-shaped patches on the skin that have red,
wavy, worm-like borders.
Some of the ways of catching Tinea is by direct skin-to-
skin contact with an infected person, by sharing items
with an infected person, or by touching a contaminated
surface
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28. Tinea capitis results in a diffuse,
itchy, scaling of the scalp that
resembles dandruff. It can cause
patches of hair loss on the scalp.
It is especially common among
children aged 3–9, particularly
children who live in crowded
conditions in urban areas.
28
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29. Scalp ringworm spreads via contaminated combs,
brushes, hats, and pillows.
Treatment
Topical treatments are ineffective
Fungistatic agents are somewhat effective
(miconazole, clotrimazole) in combination to
systemic administration of griseofulvin.
Vigorous daily scrubs of scalp help removal of
infectious debris.
29
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30. Tinea corporis means “ringworm of the body”; it involves the
non-hairy skin of the face, trunk, arms, or legs.
This would produce the classic ring-shaped patches with
worm-like borders which may occur singly or in groups of
threes and fours.
It can occur in persons of all ages.
Tinea Corporis normally resolves itself in several months
Widespread tinea corporis may require systemic griseofulvin
treatment (about 6 weeks for effective treatment)
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31. Tinea corporis – Body RingwormTinea corporis – Body Ringworm
31
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32. Tinea Pedis (athlete’s foot) produces area of redness,
scaling, or cracked skin on the feet, especially between the
toes. The affected skin may itch or burn, and the feet may
have a strong odor.
It is often acquired by walking barefoot on contaminated
floors.
Treatment of Tenia pedis includes topical antifungal agents
– tolnaftate, miconazole applied for several weeks
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34. Tinea versicolor or more commonly known as “white spots” is
caused by a fungus known as Malassezia furfur.
This fungus is present on the skin of utmost of the people but
will only cause infection in some of them. This infection is
common round the year in hot and humid climate. It occurs
more often in older children and young adults.
34
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35. The infection causes a rash which may appear on the back,
neck, upper chest, shoulders, armpits, and upper arms.
The skin rash consists of peeling, oval patches with sharply
defined borders, and pimple-like bumps.
The patches appear white or
black on dark-skinned people
and are usually pink or tan on
the more fair-skinned.
It does not cause itching unless the person is hot or sweaty.
The patches may be more prominent after the skin has been
exposed to the sun, because the patches do not tan.
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36. SUBCUTANEOUS FUNGALSUBCUTANEOUS FUNGAL
INFECTIONSINFECTIONS
If get a chance to introduce through the human skin, these fungi
have the biological ability to grow in subcutaneous tissue and
sometimes can cause significant human disease.
Different types of subcutaneous fungal infection are :
◦ Sporotrichosis
◦ Chromoblastomycosis
◦ Mycetoma
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37. Sporotrichosis (Rose-Gardener’sSporotrichosis (Rose-Gardener’s
Disease)Disease)
It is cause by Sporothrix
Schenckii, Very common fungus
that decomposes plant matter in soil
Infects appendages and lungs
Lymphocutaneous variety occurs when contaminated
plant matter penetrates the skin and the pathogen
forms a nodule, then spreads to nearby lymph nodes
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38. Treatment
Most antibiotics are ineffective
Chronic repetitive remissions and relapses are common
The chronic pulmonary form is often fatal
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39. ChromoblastomycosisChromoblastomycosis
A progressive subcutaneous mycosis characterized by
highly visible verrucous lesions:
◦ Etiologic agents are soil saprobes with dark-
pigmented mycelia and spores
◦ Fonsecaea pedrosoi, Phialophora verrucosa, Cladosporium
carrionii
◦ Produce very large, thick, yeast-like bodies, sclerotic
cells
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40. MYCETOMAMYCETOMA
When soil microbes are accidentally implanted into the
skin
Progressive, tumor-like disease of the hand or foot due
to chronic fungal infection; may lead to loss of body
part
Caused by Pseudallescheria or Madurella (ALSO CALLED
MADURA FOOT)
It is treated with iticonazole
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42. SYSTEMIC FUNGAL INFECTIONSSYSTEMIC FUNGAL INFECTIONS
These are less common but more serious. They can be
divided broadly into two types namely:
(a)endemic infections
◦ Histoplasmosis
◦ Coccidiodomycosis
◦ Blastomycosis
(b) opportunistic infection
◦ Candidiasis/candidemia
◦ Aspergillosis
◦ Zygomycosis
◦ Pneumocystis infection
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43. Histoplasmosis: Ohio Valley FeverHistoplasmosis: Ohio Valley Fever
Histoplasma capsulatum – most common true pathogen; causes
histoplasmosis
Typically dimorphic
Distributed worldwide, most prevalent in
eastern and central regions of U.S.
Grows in moist soil high in nitrogen content
Pulmonary histoplasmosis resolves itself while severe forms of
disease are usually treated by Amphotericin B.
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45. Oral ManifestationOral Manifestation
Oral lesions occurs in the form of nodules over the mucosa, which
frequently undergoes ulceration with raised, rolled borders and
induration of the surrounding tissue.
Most of the oral lesions develop in the gingiva, tongue, palate and
buccal mucosa, etc.
Some lesions may be popular, verrucous or plaque-like
Sore throat, pain during chewing, hoarseness of voice and
dysphagia are common
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46. Granulomatous lesions often cause destruction of the alveolar
bone with loosening or exfoliation of teeth
Oral lesions of histoplasmosis may occur secondary to HIV
infections and in many cases they resembles carcinoma or
tuberculous ulcers.
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47. Coccidioidomycosis: Valley FeverCoccidioidomycosis: Valley Fever
Coccidioides immitis – causative agent
Distinctive morphology – block like
arthroconidia in the free-living stage
and spherules containing endospores in
the lungs
Lives in alkaline soils in semiarid, hot
climates and is endemic to
southwestern U.S.
Arthrospores inhaled from dust,
creates spherules, and can form
nodules in the lungs
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49. The lesions of skin and oral mucosa are proliferative,
granulomatous, ulcerated and non specific in their
clinical appearance
Treatment
Amphotericin B has been found to provide
chemotherapeutic control of the disease
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50. Blastomyces Dermatitidis:Blastomyces Dermatitidis: North AmericanNorth American
BlastomycosisBlastomycosis
Dimorphic
Free-living species distributed in soil of a large section of the
midwestern and southeastern U.S.
Inhaled 10-100 conidia convert to yeasts and multiply in lungs
Symptoms include cough and fever
Chronic cutaneous, bone, and nervous system complications
Amphotericin B is the drug of choice
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52. Oral ManifestationsOral Manifestations
Proliferative, ulcerated lesions developing over the palate,
lips, tongue, gingiva and maxilla or mandible
Loosening of teeth and draining sinuses.
Oropharyngeal pain and cervical lymphadenopathy.
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53. Invasive Candidiasis/CandidaemiaInvasive Candidiasis/Candidaemia
It is caused by C. albicans and other non-
albicans Candida spp.
Types of systemic/invasive candidiasis are:
Candidial meningitis
Candidial endocarditis
Candidial septicaemia
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54. Candidal EndocarditisCandidal Endocarditis
Patients who have undergone prosthetic heart valve
replacement and those who are using long time venous
catheters are at risk for developing candidal endocarditis.
Clinically the patients often develpes fever, dyspnoea,
edema and congestive cardiac failure, etc.
Candidial growth in the valve may result in the
development of major venous embolism
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55. Candidal MeningitisCandidal Meningitis
Spread of candidal organism into the brain results in
meningitis, which could be a consequence of oral
candidiasis and in such cases, the organism can be
detected from the CSF.
Patients often develop fever, headache, stiffness in the
body and hemiplegia.
The condition is often fatal.
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56. Candidal SepticaemiaCandidal Septicaemia
It occurs due to disseminated spread of candidal
organisms throughout the body and it can be secondary
to serve oral or oropharybgeal candidiasis.
Clinically the patients often develop fever, chill, nausea,
vomiting, shock, coma etc.
The condition can be fatal if not treated in time.
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57. AspergillosisAspergillosis
Very common airborne soil fungus
600 species, 8 involved in human disease; A. fumigatus most
commonly
Serious opportunistic threat to AIDS, leukemia, and transplant
patients
Infection usually occurs in lungs – spores germinate in lungs and
form fungal balls; can colonize sinuses, ear canals, eyelids, and
conjunctiva
Invasive aspergillosis can produce necrotic pneumonia, and
infection of brain, heart, and other organs
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58. Treatment is by oral intake of anti-fungal agents such as Amphotericin B and
nystatin
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59. ZygomycosisZygomycosis
Zygomycota are extremely abundant saprobic fungi found in
soil, water, organic debris, and food
Genera most often involved are Rhizopus, Absidia, and Mucor
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60. • Usually harmless air contaminants invade the
membranes of the nose, eyes, heart, and brain of
people with diabetes and malnutrition, with severe
consequences
Treatment
Control of the predisposing factors such as diabetes
Surgical excision if the lesion is localised
Administration of Amphotericin
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61. Pneumocystis (Carinii) JiroveciPneumocystis (Carinii) Jiroveci andand
PneumocystisPneumocystis PneumoniaPneumonia
A small, unicellular fungus that
causes pneumonia (PCP), the most
prominent opportunistic infection
in AIDS patients
This pneumonia forms secretions
in the lungs that block breathing
and can be rapidly fatal if not
controlled with medications like
Pentamidine and cotrimoxazole
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63. PRECAUTIONS TO PREVENTPRECAUTIONS TO PREVENT
FUNGAL DISEASESFUNGAL DISEASES
Washing your feet every day.
Drying your feet completely, especially between your toes.
Wearing sandals or shower shoes when walking around in
locker rooms, public pools, and public showers.
Wearing clean socks. If they get wet or damp, be sure to
change them as soon as you can.
Using a medicated powder on your feet to help reduce
perspiration (sweating). Ask a parent first.
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64. Wearing clean cotton underwear and loose-fitting pants.
Keeping your groin area clean and dry.
Changing out of wet swimsuits instead of lounging around in
them.
Wearing clean cotton underpants.
Trying not to let your skin get too hot or sweaty.
Using an anti-dandruff shampoo to wash your skin once a
month.
Make sure shoes fit correctly and are not too tight.
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