MICROPARA LE 4: MYCOLOGY

fungi

• microscopic eukaryotic organisms

• first classified under kindome plantae, later separately classified under kingdom fungi

  • due to the presence of unique rigid cell wall, which is chemically diffrent from the bacterial cell wall

  • non photosynthetic

  • similar appearance w/ plants

• 80K species described: 400-medically important, <50 responsible for more than 90% of fungal infections of humans and animals

• FUNGAL CELL WALL

  • rich in carbohydrates: polymers of acetylglucosamine “CHITIN”, forming a thick layer protecting inner organelles from the adverse external environment

• CELL MEMBRANE

  • contains ERGOSTEROL; organized nucleus mores often reproduce by asexual spores (but can also produce sexually)

• produce multi-celled hyphae or single-celled yeasts

• classified according to morphology and taxonomy

fungal cell wall

• boxes = antifungal drugs

• distinct about ungi is the presence of CHITIN

• fungi look like plants macroscopically, but looke more like animal kingdom microscopically (they are closely related to animals than plants)

morphological classification of fungi

• yeast

• moulds

• dimorphic

hyphae

• tubular-like structure that compose a mold colony

• help in the interexchange of cytosol and organelles between adjacent cells

• may be septate or pauciseptate

• may be pigmented or not

septae

cross walls present in some hyphae; singular: septa

nonseptae

lacking septa

hyaline

• lacking pigment

• molds do not have pigment; they are colorless and transparent

dematiaceous

containing dark pigment

chlamydoconidia

large, round spores in or on hyphae

conidia

asexual spores produced by molds with septa

mycelium

a colony, made up of rope-like filaments called hyphae

spores: conidia

• produced in a CONIDIOPHORE

• macroconidia/microconidia

• spores or hyphae may be pigmented or not

• not all can be found in every fungal species

chlamydospore

spores that grow on the hyphae itself (circles)

arthroconidia

bigger segments on the hyphae compared to the septae

sporangiospores

found int he sporangia connected to the hyphae

• conidia are connected tot he conidiophore connected to the hyphae

sporangiophore

• hyphae specialized in bearing sporangia

• rhizopus and mucor

aspergillus and penicillium

these closely resemble conidiospores and conidia

mould

1. Eukaryotic Organisms

• Moulds have complex cells with a true nucleus and membrane-bound organelles.

2. Multicellular (Filamentous)

• Most moulds grow as filamentous hyphae, which form a network called mycelium.

• These hyphae may be septate (with cross-walls) or coenocytic (without cross-walls).

3. Heterotrophic (Saprophytic or Parasitic)

• Moulds cannot make their own food.

• They absorb nutrients from dead organic matter (saprophytic) or from living hosts (parasitic).

4. Reproduction (Sexual and Asexual)

• Asexual reproduction is most common and occurs through spores (like sporangiospores or conidia).

• Sexual reproduction involves specialized spores like zygospores, ascospores, or basidiospores, depending on the fungal class.

5. Rapid Growth

• Under favorable conditions (moist, warm, nutrient-rich), moulds can grow and spread quickly.

6. Cell Wall Made of Chitin

• Unlike plants (which have cellulose), mould cell walls are made of chitin, a strong, flexible polysaccharide.

7. Thallus Structure

• The vegetative body of a mould is called a thallus, which is composed of mycelium (mass of hyphae).

8. Colonial Appearance

• Moulds grow in colonies that may appear fuzzy, cottony, or powdery, often in colors like green, black, white, or grey depending on the species.

9. Common Habitat

• They thrive in moist, warm environments — soil, decaying matter, stale food, walls, etc.

10. Importance

• Positive: Used in antibiotics (e.g., Penicillium), cheese production, decomposition.

• Negative: Can cause spoilage, allergies, and fungal infections (e.g., Aspergillus, Rhizopus).

yeast

• unicellular eukaryotic organisms (unlike molds which are multicellular)

• appear smooth and mucoid on the media

• aerobic organisms, but growth is enhanced in ANAEROBIC CONDITIONS

• acquire energy from an organic compound by oxidation

• a single cell produces ASEXUALLY through budding

• the third “new cell” produces a daughter cell and each cell has a nucleus, cytoplasm, reserve food bodies and a vacuole

  • vacuole is one distinctive feature of the yeat with the budding

dimorphic fungi

• exists in both mycelial and yeast forms in varying temperatures

37C

yeast like colonies grow best in this temperature

25C

mould like colonies grow best in this temperature

pathogenic

yeast forms are ____

saprophytic

mould forms are ___; loves to feed on dead plants and animal remains - this is why fungi are big factors and contributors to decomposition

Genus	Common Name	Use/Impact
Penicillium	Blue/green mould	Antibiotics, cheese
Aspergillus	Black mould	Allergies, aflatoxins
Rhizopus	Bread mould	Spoilage, fermentation

25C

at ___, the forms are mycelial, or they look like molds

37C

at ___, the forms look like yeast

opportunistic fungi

these are the different forms of fungi that we can see, and the fungi that can cause diseases or mycosis

opportunistic fungi

• first, yeast cells. we have the parent yeast cell; it buds to produce daughters. during budding it can produce pseudohyphae or a germ tube

  • pseudohyphae - chains of elongated yeast cells that remains attached after budding

  • germ tube - a tube like outgrowth from a yeast cell that does not have constriction at the base. it is a sign of yeast transitioning to a more invasive form, mould.

• there are also the mould forms: candida and hyphae or hypha

• cryptococcus is somewhat unique because of the presence of capsules

  • a genus of yeast-like fungi

  • cryptococcus neoformans - medically important which causes infections in the brain or lungs

zygomycetes

• lower fungi with non-septate hyphae produce sporangiospores (asexual spores)

• the spres are inside the sporangium, so they are called sporangiospores

ascomycetes

• produces septate hyphae and ascospores. (sexual spores are present inside the sac or ascus)

• inside the ascus, there are the ascus spores

basidiomycetes

• produce septate hyphae and basidiospores (sexual spores are present inside the basidium)

• the basidium looks like long, goblet cells, at the top are the basidiospores

• the goblets are called basidium.

• basiosopores are the name of the spores found on the basidium

deutromycetes

• fungi imperfecti

• produces septate hypahe and cannot be classified into sexual or asexual because their sexual state is unknown

• share common features with ascomycetes

• most medically important fungi belongs to this group

taxonomic classifications of spores

1. Zygomycetes

• Definition: Zygomycetes are a class of fungi that reproduce sexually through the formation of zygospores, which are thick-walled resting spores formed by the fusion of two similar-looking gametes (isogamous). They also reproduce asexually using sporangiospores inside sporangia.

• Structure: Their hyphae are usually coenocytic (no cross-walls).

• Example: Rhizopus stolonifer — commonly known as black bread mould.

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2. Ascomycetes (Sac Fungi)

• Definition: Ascomycetes are fungi that reproduce sexually by forming ascospores inside a sac-like structure called an ascus. They also reproduce asexually through conidiospores (conidia).

• Structure: They have septate hyphae (with cross-walls).

• Example: Aspergillus species — some cause lung infections; others are used in food fermentation.

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3. Basidiomycetes (Club Fungi)

• Definition: Basidiomycetes reproduce sexually by forming basidiospores on a club-shaped structure called a basidium. These fungi are often large and visible (like mushrooms).

• Structure: Their hyphae are septate, and they often form fruiting bodies (basidiocarps).

• Example: Agaricus bisporus — the common edible mushroom you find in groceries.

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4. Deuteromycetes (Fungi Imperfecti)

• Definition: Deuteromycetes are fungi without a known sexual stage. They are classified based on their asexual reproduction, usually through conidia. Many medically important fungi belong here.

• Structure: Usually have septate hyphae.

• Example: Candida albicans — a dimorphic fungus that causes candidiasis in humans.

zygomycetes - rhizopus stolonifer

• A class of fungi that reproduce sexually by forming zygospores, which are thick-walled spores resulting from the fusion of similar gametes. They also reproduce asexually through sporangiospores produced inside sporangia. Their hyphae are usually coenocytic (lacking cross-walls).

• Example: R______ s________ (black bread mould)

ascomycetes - aspergillus spp.

• Definition: Fungi that reproduce sexually by forming ascospores within a sac-like structure called an ascus, and asexually through conidiospores (conidia). They have septate hyphae.

• Example: A_________ spp. (some species cause lung infections or are used in fermentation)

basidiomycetes - agaricus bisporus

• Definition: These fungi reproduce sexually by forming basidiospores on a basidium (a club-shaped structure). They typically form large fruiting bodies like mushrooms and have septate hyphae.

• Example: A_______ b________ (common edible mushroom)

deutromycetes - candida albicans

• Definition: A group of fungi with no known sexual stage, classified based on asexual reproduction, usually through conidia. Most have septate hyphae and include several medically important fungi.

• Example: C______ a________ (causes candidiasis)

sexual spores

• zygospores - found between hyphae

• ascospores - found inside the ascus; if ascus bursts, then the ascospores will be dispersed

• basidiospores - basidium looks like goblet cells; basidiospores, on top of it, what connect the basidiospores and basidium is the sterigmata; sterigmata looks like small feet or pods connecting the spores to the basidium

asexual spores

• vegetative spores

  • formed by budding (yeast cells)

  • formation of speta in hyphal filament (moulds)

  • folding and thickening of hyphal filaments (resulting in thick-walled spores)

• aerial spores

  • conidiospores

  • microconidia

  • macroconidia

  • sporangiospores

• labels

  • conidiospore

  • phialides

  • vesicle

  • conidiophore

  • septate hyphae

advantages of fungi

• decomposition - carbon cycle = plants grow

• fermentation

• food

• pharmaceuticals - fungal metabolites are used in antibiotic drugs like penicillin = came from penicillium spp.

• model research organisms - fungi are the basis of genetic research becaue of their simle eukaryotic form. before they proceed to the multi-celled, complicated-complex forms like humans, they start with the simpler ones, like fungi and bacteria

disadvantages of fungi

• tree disease

• crop disease

• food spoilage - bread molds, food molds, expiration date molding

• wood and timber degradation

• mycoses or fungal infection

mycoses

• they are fungal infections.

• diseases caused by fungi

causes of mycoses to humans

1. inhalation of spores - enter through the lungs, gets localized, causes respiratory infection

2. inoculation of spores - through cuts, localized i the skin

3. alteration of normal flora - due to overconsumption of heavy dose of antibiotics (alter or kills normal flora that acts as a physical barrier, this enhancing entry of pathogenic fungi)

4. suppressed immune system - patients undergoing chemotherapy, in steroids due to transplantation, HIV, or diabetics

4 subtypes of mycosis

• superficial mycosis

• subcutaneous mycosis

• deep mycosis

• opportunistic mycosis

superficial mycosis

• externally localized on th layers of the skin, hair, nails and grow well on dead layers

• classified into two: surface mycoses and cutaneous mycoses

tinea versicolor

• caused by MALASSEZIA GLOBOSA

• is a yeast form of fungi that live on the skin i few numbers but multiply dururing adverse conditions leading to skin infections

• they can exist as a normal flora, but during adverse conditions, and with te several causes mentioned earlier, it can lead to skin infection

tinea versicolor

pathogenesis: malassezia globosa

• transmission

  • transmitted through contact, through adherence and invasion of fungi

  • become apthogenic when they change morphology from yeast to mycelium (mold colony)

  • dimorphic in nature

• pigmentation

  • due to azelaic acid, which is the econdary metabolite produced by fungi. it reacts on the melanin pigments that is found on the skin, thus producing pigments (patches)

• s/s

  • mild patches on cehst, back, neck, and arms

  • patches lead to pigmentation

  • discoloration starts spreading in untreated conditions

  • dryness of the skin

  • itching of the skin

tinea versicolor

lab diagnosis: malassezia globosa

• specimen

  • skin scrapings of the lesions (superficial layers is enough)

• direct microscopy

  • KOF (potassium hydroxide) wet mount. skin scraping is fixed on slide with 20% KOH, and then the skin scraping is mixed into that wet mount, covered with a cover slip and tehn short unbranched hyphae can be observed

• culture:

  • saubrouraud’s dextrose agar @ 32-37C

  • round and smooth colonies

  • after the culture, it is then mounted on lactophenol cotton blue wet mount to further see the morphology of the malassezia species

treatment for tinea versicolor

• topical applicaiton of antifungal ointments

  • WHITEFIELD’S OINTMENT - composed of benzoic acid, salicylic acid, ciclopirox olamine, and tincture of iodine

  • sulfur containing ointment

  • oral antifungals - triazole, itraconazole, ketoconazole. used in more severe cases.

tinea nigra

• caused by HORTAEA WERNICKII

• dimorphic fungi taht exists in both yeast and hyphal forms

• responsible for asymptomatic mycoses

• saprophytic in nature and found on dead and decayed materials

tinea nigra

pathogenesis: hortaea wernickii

• entry

  • inoculation of fungus through cuts and wounds

  • enter, localize, and cause superficial infection on palms and foot soles

  • from the name itself, you can deduce that the color is darker, compared to tinea versicolor

• halotolerant

  • it is tolerant to ionic stress, or the ability of tolerance is the ability of an organism to grow at salt concetrations higher than those for growth

  • able to survive in human tissues by ccumulating and utilizing melanin. it can survive on areas of the skin that actually are more prone to sweat, like palms and foot soles

  • because of its appearance, there are times that this mycoses is confused witht he type of skin cancer or melanoma

• s/s

  • mild patches on palms and foot soles

  • patches appear brownish or black in color, irregular in shape

  • scale-like skin growth

  • itching

  • if asymptomatic, you cannot see any of these symptoms. but there is funal present still on the skin

tinea nigra

lab diagnosis: hortaea wernickii

• specimen

  • skin scrapings of the lesions (superficial)

• direct microscopy

  • KOH wet mount, budding yeast cells on branched hyphal elements

• culture

  • SDA, at 32C -37C, 3 weeks: dematiaceous colonies that become velvety with age

  • in culture, they appear mycelial bold-like forms, unlike the malassezia that appears yeast-like

  • very slow forming fungal colony (coin-sized)

• lactophenol cotton blue

  • further testing of isolated colonies

  • this is the wet mount usinf LPCB because it is blue and it can be seen more clearly, compared to the previous slide which contains KOH wet mount

  • these fungal colonies are that much clearer

  • you can see the form is fully mycelial

  • previous slide was not that clear because there is a mixture of yeast cells and mycelial hyphal elements - like in the middle transformation

  • since the LPCB gets its specimen formt he colony grown in culture, you can see the form is now full mycelial or hyphal

tinea nigra

treatment: hortaea wernickii

• topical applicaiton of antifungal ointments

• good hygiene

• avoiding exposure to moist and dirty places

piedra

• this affects the hair

  • white p___

  • black p___

white piedra

• caused by TRICHOSPORON BEIGELII

• asexually reproductive

• part of normal flora

• yeast-like fungi that change to septate hyphal filaments

• dimorphic

white piedra

pathogenesis

• trichosporon beigelii

• close contact with the infected person’s towel, soap, comb, etc.

• white nodules: spores transmitted by contact

symptoms

• acclimation of white lump of yeast cells on the hair follicles of the head, beard, even pubic hair

• you can directly egt this and place t on the wet mount and immeadiately see the yeast cells

• hair loss

• itching

black piedra

• caused by PIEDRAIA HORTAE

• asexual

• transmitted through contact

black piedra

pathogenesis

• found on thehair shafts of the beard and scalp

symtoms

• brown to black nodules firmly attached to the hair shaft

• nodules: ascostroma (asci and ascospores)

• mostly asymptomatic

• hair breakage in extreme cases

black piedra

lab diagnosis

• specimen: hair

• direct microscpoy: KOH wet mount hair nodules

• culture: sabourand dextrose agar

• LPCB: further testing of isolated colonies can be done through LPCB

treatment

• topical application of antifungal ointments

  • imidazoles and selenium sulfide

  • amphotericin b ointments

  • using separate towels, soaps and combs

subcutaneous mycosis

• causes disease in living tissue leading to tissue damage

• three types:

  • mycetoma

  • chromoblastomycosis

  • rhinosporidiosis

mycetoma

• caused by ACTINOMYCETES (actinomycetoma) or filametous fungi: EUMYCETOMA

• persistent subcutaneous granulomatous infection affecting the foot, and as infection progresses, the bones

• aka MADURA FOOT

• not just causde by fungi but also bacteria such as the ACTINOMYCETES

pathogenesis

• transmission

  • inoculation of fungus through cuts or wounds from soil

  • enters tissue, localize, and replicatie inside living cells

  • spores from clumps inside cells resulting in granules

    • granules may vary in color, depending on contributing agents

• s/s:

  • itching

  • swelling in the area of itching

  • pus formation

  • ulceration and nodules

  • pus expulsion

  • irrigation in area of infection (watery irrigation)

  • disfiguration of the leg

mycetoma

lab diagnosis

• specimen: pus exudates

• direct microscopy

  • gram staining - for identification of actinomycetes (gram positive)

  • KOH wet mount hair nodules for identification of eumycetes (fungi)

• culture

  • after the direct microscopy, if it is found to be a bacteria, then it can be grown on BA or NA

  • if fungi, then it is grown on sauboraud’s dextrose agar SDA

treatment

• surgery and removal of abcess at early stage with proper administration of oral antifungal and antibacteruak drug therapy (to prevent the further spread of the fungi)

  • ACTINOMYCETOMA - antibacterial drug; rimfampicin, dapsone and sulphonamides

  • EUMYCETOMA - oral antifungal; itraconazole and ketoconazole

• treatment should be prolonged for complete eradication of pathogens.

chromoblastomycosis

• caused by five different vegetative fungi (pathogens):

  • phialophora verrucosa

  • fonsecaea compacta

  • fonsecaea pedrosoi

  • rhinocladiella aquaspersa

  • cladophialophora carrionii

• cause persistent infection that slowly progress and form granulomatous lesion

  • leads to accumulation of ketinocytes in epidermal layer resulting in sloughing skin

• caused by ACTINOMYCETES (actinomycetoma) or filamentous fungi - EUMYCETOMA

  • aerobic, filamentous fungi commonly found ind soil

chromoblastomycosis

pathogenesis

• chronic subcutaneous infection

• transmission: cuts or wounds, primarily in leg region

  • upon entry, fungi spreads adn invades tissue very slowly (due to growing capacity)

  • very resistant to immune cells due to its melanin cell wall

• affects tissue:

  • forming hyperplasia of epidermis producing nodules with pus formation

  • distinct feature: painless

• drains lymphatics

  • severe: damage organs

  • it can take years undetected. it starts with nodules, if not treated, then it can drain the lymphatics, and cause organ damage

• s/s:

  • itching are of entry

  • swelling with pus formation

  • nodule formation as infecting drains to lymph

  • ulcerations

chromoblastomycosis

lab diagnosis

• specimen: pus cells or skin scrapings

• methods:

  • KOH wet mount

  • histopathological analysis: check multinucleated giant cells with granules and sclerotic bodies inside the outside cells

  • culture: SDA, brown or black moldy colonies

treatment

• surgery and removal of pustule and proper oral treatment heat threapy (early stages)

• antifungal agents:

  • flucytosine

  • ketoconazole

  • itraconazole

rhinosporidiosis

• caused by RHINOSPORIDIUM SEEBERI

• granulomatous infection of the nose, eyes, and mouth

• first classified as sporozoan parasite, but later classified as lower fungi

• still shares morphological similarities with aquatic parasites

• ccording to DNA sequencing, they belong to fish parasites (which is right in between animala nd fungal division)

pathogenesis

• fishermen adn washermen are mostly affected due to constant contact with water habitats

• mode of transportation:

  • entry thru cuts and wounds

  • also enters thru nasopharyngeal route or even eyes and external genitalia

• s/s:

  • accumulation of large mass of cells that hangs out as separate layer

  • pus accumulation leafing to foul sme;;

  • breathing difficulty due to protrusion of layer

• lab diagnosis:

  • skin biopsy: histopathological analysis

  • KOH wet mount: for endospores within sporangium

• treatment:

  • surgery

  • intravenous administration and AMPHOTERICIN B and DAPSONE

deep mycosis

• aka SYSTEMIC MYCOSIS

• involve both pathogenic and opportunistic fungi yeast form and start invading tissue

  • pathogenic fungi: gain entry

  • oppportunistic fungi: suppresses the immune system system

histoplasmosis

• systemic mycosis caused by HISTOPLASMA CAPSULATUM

  • saprophytic fungi mostly found in soil

  • dimorphic fungi

  • solo-celled microconidia

• colony: produces moldy white colonies

• affects respiratory syste causes pulmonary infection

pathogenesis

• intracellular pathogen

• mot: inhalation: molds -convert→ yeast

  • yeast cells engulfed by alveolar macrophages

  • yeast replicates inside and use th host cells to travel around the body and invade other areas like liver, spleen, and lymph nodes

• results in pulmonary infection in men, children and immunocompromised pxs (HIV-AIDS and undergoing chemotherapy)

• s/s:

  • dry cough

  • body pain

  • high fever

  • restlessness

  • lymphadenopathy

  • fatal in sever cases affecting liver, eyes, and glands

lab diagnosis

• specimen: sputum, urine, throat swab, bone marrow apirator

• direct microscopy: histopathological staining or geimsa staining to view intracellular yeast (biopsy specimen)

  • KOH will nor work

• culture: SDA (for moldy colonies), blood agar (for yeast colonies

• serology: complement fixation test and enzyme immunoassay

  • does not involve th efungi itself

  • involves antibody-antigen reaction

  • reacts to blood antigen

  • one of the fastest tests due to fungal colonies needing to take a few days for culture to develop

treatment

• ITRACONAZOLE

• AMPHOTERICIN B

• relapses may occur for immunocompromised patients (prolonged treatment with itraconazole)

oppotunistic mycosis

• ifection tha occurs in immunocompromised pxs

• depends on the load of organism and the virulence caused to the host

  • CANDIDIASIS

  • CRYTPOCOCCOSIS

candidiasis

• caused by candida albicans, candida tropicalis, candida parapsilosis and candida krusei

• part of the normal flora of the skin and GIT

• cells are oval-shaped and divide by budding , which forms into pseudohyphae

• some species of candida albicans are DIMORPHIC

Symptoms by Affected Area: 

• Vaginal (Yeast Infection): 

  • Itching and soreness in the vaginal area. 

  • Abnormal vaginal discharge (often thick and white). 

  • Burning sensation, especially during urination. 

  • Redness and swelling of the vulva. 

• Oral (Thrush): 

  • White or yellowish patches on the tongue, inner cheeks, gums, or throat. 

  • Redness and soreness in the mouth. 

  • Cotton-like feeling in the mouth. 

  • Loss of taste. 

  • Pain or difficulty swallowing (if it spreads to the throat). 

  • Cracking and redness at the corners of the mouth. 

• Skin : 

  • Rash (often red and itchy). 

  • Scaling or flaking of the skin. 

  • Small pustules (pus-filled bumps). 

  • Skin may become cracked and sore. 

  • Areas like skin folds, underarms, groin, and between fingers are prone to infection. 

• Esophageal : 

  • Pain and difficulty swallowing (dysphagia). 

• Invasive : 

  • Fever and chills. 

  • Symptoms may vary depending on the organs or bloodstream affected. 

Other General Symptoms:

• Fatigue.

• Bloating, gas, constipation, or diarrhea.

• Brain fog (difficulty concentrating).

• Skin rashes.

• Nutritional deficiencies (linked to Candida overgrowth).

• Cravings for sugary or high-carbohydrate foods.

• In infants, persistent diaper rash can be a sign. 

candidiasis

Symptoms by Affected Area: 

• Vaginal (Yeast Infection): 

  • Itching and soreness in the vaginal area. 

  • Abnormal vaginal discharge (often thick and white). 

  • Burning sensation, especially during urination. 

  • Redness and swelling of the vulva. 

• Oral (Thrush): 

  • White or yellowish patches on the tongue, inner cheeks, gums, or throat. 

  • Redness and soreness in the mouth. 

  • Cotton-like feeling in the mouth. 

  • Loss of taste. 

  • Pain or difficulty swallowing (if it spreads to the throat). 

  • Cracking and redness at the corners of the mouth. 

• Skin : 

  • Rash (often red and itchy). 

  • Scaling or flaking of the skin. 

  • Small pustules (pus-filled bumps). 

  • Skin may become cracked and sore. 

  • Areas like skin folds, underarms, groin, and between fingers are prone to infection. 

• Esophageal : 

  • Pain and difficulty swallowing (dysphagia). 

• Invasive : 

  • Fever and chills. 

  • Symptoms may vary depending on the organs or bloodstream affected. 

Other General Symptoms:

• Fatigue.

• Bloating, gas, constipation, or diarrhea.

• Brain fog (difficulty concentrating).

• Skin rashes.

• Nutritional deficiencies (linked to Candida overgrowth).

• Cravings for sugary or high-carbohydrate foods.

• In infants, persistent diaper rash can be a sign. 

cryptococcosis

• caused by:

  • CRYPTOCOCCUS NEOFORMANS

  • CRYPTOCOCCUS GATTII

• mostly found in soil, feces of birds

• yeast-like fungi with resistant polysacchardie capsules

• can be cultures using fungal or bacteriological media, 24 hrs at 37C

• colony: produces mucoid white colonies (due to capsule)

PATHOGENESIS

● Mode of transmission: inhalation of fungal cells

● Enter respiratory system, affecting circulating

cells and compromises immune system by

resisting immune reactions

● Multiply and infect other parts of the body,

especially the CNS causing meningoencephalitis

(inflammation of brain tissues and meninges)

● Symptoms:

○ Fever

○ Headache

○ Body pain

○ Flu symptoms

○ CNS affected in severe causes, causing

encephalitis

LAB DIAGNOSIS

● Specimen collected: Sputum, Blood (severe

systemic cases), Throat swab, CSF (suspected

encephalitis)

● Direct microscopy

○ India Ink: special staining used specifically for

showing the capsule of Cryptococcus spp.

● Serology

TREATMENT

● Amphotericin B and flucytosine

○ Combination of both for severe cases (ie:

immunocompromised patients)

○ Prolonged treatment provided to avoid

recurrent infections