Mhr Topic 22: Characteristics Of Fungi

Front 1

Are fungi autotrophs or heterotrophs?

Back 1

Heterotrophs; need preformed carbon for growth.

Front 2

Endogenous v.s. exogenous

Back 2

Endogenous comes from normal flora, exogenous comes from outside.

Front 3

Dimorphic fungi

Back 3

Are yeasts in body tissue at body temp but are molds in culture at ambient temp (except Candida).

Front 4

Sporulation

Back 4

Way which filamentous fungi reproduce. Metabolically dormant, produce sexually or asexually, and unlike bacterial spores, are actual quite fragile.

Front 5

Cutaneous mycoses location of infection

Back 5

AKA dematophytes. Cause infections of the skin, hair, and nails. Use Keratin as source of nutrition and do not invade non-ketarinized tissue.

Front 6

Cutaneous mycoses types and infection locations

Back 6

1) Trichophyton - Infects hair, skin, and nails
2) Microsporum - Infects hair and skin
3) Epidermophyton - Infects skin and nails

Front 7

Cutaneous mycoses mode of transmission

Back 7

By infected skin scales; animal to human or human to human

Front 8

Tinea pedis disease

Back 8

cutaneous mycoses. Athletes foot

Front 9

Tinea corporis disease

Back 9

cutaneous mycoses. Ringworm

Front 10

Tinea capitis disease

Back 10

Scalp ringworm, cutaneous mycoses.

Front 11

Tinea cruris disease

Back 11

Jock itch, cutaneous mycoses.

Front 12

Tinea unguium disease

Back 12

Onychomycosis, cutaneous mycoses.

Front 13

Treatment of cutaneous mycoses

Back 13

Oral or topical therapy. Nail infections require oral therapy for months.

Front 14

Subcutaneous mycoses location of infection

Back 14

Dermis, sub Q tissue, and bone.

Front 15

Subcutaneous mycoses infection

Back 15

Causative agents reside in soil and decaying live vegetation. More common if frequent contact with soil and vegetation without protection. Usually via traumatic lacerations and puncture wounds.

Front 16

natural location of cutaneous mycoses

Back 16

Divided into 3 groups:
Anthropophilic - residing on human skin
Zoophilic - residing on animals
Geophilic - residing in soil.

Front 17

Sporothrix schenckii disease

Back 17

Subcutaneous mycoses. Causes Sporotrichosis. Get granulous lesions at puncture site and secondary lesions along draining lymphatics. Can be self limiting or chronic.

Front 18

Sporothrix schenckii (form, culture characteristics)

Back 18

Dimorphic, yeast form in infectious tissue.
Mycelial (filamentous) form in culture at low temps.

Front 19

Chromomycosis disease

Back 19

Subcutaneous mycoses. Usually causes warty, pigmented fungi which spread along lymphatics and develope into crusty abscesses.

Front 20

Mycetoma disease

Back 20

Subcutaneous mycoses. Caused by various soil fungi and actinomycetes (bacteria). Localized Colored grains (black, white, yellow, red) Usually on feet. Discharges pus, serum, and blood through sinuses. Can spread to bone causing crippling deformities.

Front 21

What type of fungi are all true systemic mycoses?

Back 21

Dimorphic

Front 22

True systemic mycoses (name em)

Back 22

Coccidiodomycosis
Histoplasmosis
Blastomycosis
Paracoccidiomycosis

Front 23

Opportunistic systemic mycoses

Back 23

Candidiasis
Cryptococcosis
Aspergillosis
Mucormycosis
Pneumocystis juroveci

Front 24

Systemic mycoses infection and general disease

Back 24

1) Infection via inhilation of airbprn spores.
2) Spores germinate in lungs.
Asymptomatic primary pulmonary infection is common. Acute pulmonary disease is less common. Chronic or disseminated infection usually only in immunocompromised.

Front 25

Coccidiodes immitis Infection and disease

Back 25

1) In soil, fungus produces barrel-shaped arthrospores which are inhaled
2) True systemic mycoses. Causes Coccidiodomycosis:
Causes pullmonary infection or can disseminate into bones.

Front 26

Coccidiodes immitis location and diagnosis

Back 26

Usually found in the arid locations of southwest as well as central and south america.
Culture: barrel shaped arthrospores. Dangerous to manipulate, easily becomes airborne.
Histopathology, and serology.

Front 27

Histoplasma capsulatum infection and disease

Back 27

1) Fungi found in soil. Produce conidia which are inhaled into lungs and germinate into yeast like cells. Yeast cells engulfed by macs where they multiply.
2) True systemic mycoses. Cause Histoplasmosis:
Can be asympomatic, acute, chronic or disseminated. Disseminated in immunocompromised and children. Disseminated causes disease in many organs and sites.

Front 28

Histoplasma capsulatum location and diagnosis.

Back 28

1) Mainly ohio and mississippi river valleys. Found in soil with high nitrogen content like areas contaminated with bat and bird droppings.
2) Hallmark of fungus is that its an intracellular pathogen. can culture blood, BM, and tissue. Antigen detection in blood and urine. Antibody detection.

Front 29

Blastomyces dermatitidis Infection and disease

Back 29

1) Found in soil, conidia inhaled, enter lungs. Germinate into thick walled yeast.
2) True systemic mycoses. Cause Blastomycosis:
Pulmonary usually asymptomatic. Can get a symptomatic pulmonary or disseminated infection. Disseminates to skin, bones, organs, CNS.

Front 30

Blastomycosis location and diagnosis

Back 30

Found in states bordering ohio and mississippi river valleys and the great lakes. Can diagnose via direct microscopy, culture of sputum, lung biopsy, or other tissue. Serology and antigen detection do NOT work.

Front 31

Paracoccidiodomycosis infection and disease

Back 31

True systemic mycoses. Clinical presentation similar to histo and blasto EXCEPT secondary site of infection is mucosa of nose and mouth where destructive lesions can develop. 90% of symptomatic disease occurs in males.

Front 32

Paracoccidiodomycosis location and diagnosis

Back 32

Major endemic dimorphic fungus of latin america. Also known as South American blastomycosis.
Culture - Mariner's wheel morphology at 37 Cecilius.
Serologic testing also works.

Front 33

Candida albicans infection and disease

Back 33

1) Most infections are endogenous. Normal flora of skin, mucous membrane, GI, GU tract.
2) Opportunistic systemic. Not considered dimorphic because yeast and hyphal forms can be seen at same temp. Causes Candidiasis:
Mucotaneous - thrush, vulvovaginitis, esophagitis, diaper rash. Systemic in immunocompromised, can involve many organs.

Front 34

Candida albicans location and diagnosis

Back 34

Normal flora of skin, mucous membrane, GI and GU tract.
Culture - Standard. Germ tube formation, pseudophyphae. Reproduce by budding. Yeast and hyphal forms at same temp.

Front 35

Cryptococccus neoformans infection and disease

Back 35

1) Infection caused by Yeast.
2) Opportunistic systemic. Cryptococcocis:
Mild lung infection. Can go to brain and meninges. Usually in immunocomprimised but not always.

Front 36

Cryptococccus neoformans location and diagnosis

Back 36

Found worldwide in soil containing bird (especially pigeon) droppings.
Can see very thick capsule via india ink stain.

Front 37

Aspergillosis non-allergic disease

Back 37

Superficial Syndromes - Otomycosis (ear infection), Onchomycosis (nail infection), and Keratitis (Cornea infection).
Invasive - Invasive aspergillosis can cause hemoptysis (cough up blood) b/c angioinvaision of endothelium.
Disseminated disease spreads from pulmonary and has high mortality.

Front 38

Aspergillosis allergic disease; who gets is.

Back 38

Immunocompetent people. 1% in people with asthma, 15% in people with CF.

Front 39

Aspergillosis allergic disease

Back 39

1) High IgE and eosinophilia can lead to polmonary fibrosis
2) Hypersensitivity pneumonitis
3) Bronchiectasia - Destruction of muscle and elastic tissue leads to irreversible dilation of bronchial tree.
4) Breathlessness and coughing fits common.

Front 40

Aspergillosis diagnosis

Back 40

Positive skin prick test with aspergillosis extract (immediate hypersensitivity).
Look for granulomas in tissue.
See radiating chains of hyphae with 45 degree dichotomous branching.
Can also culture and detect antigen in serum.

Front 41

Mucormycosis infection and disease

Back 41

1) Caused by Zygomyccetes group of filamentous fungi (non-septate fungi). Infection only in peeps with diabetes, burns, or immunosupression.
2) Systemic opportunistic. Rhinocerebral mucormycosis - Begins in nasal mucosa and progresses to orbit, palate, and brain. Very aggressive, rapidly fatal.
Pulmonary mucormycosis - Severe tissue destruction pneumonia in neutropenic peeps.
cutaneous " - trauma associated
GI " - Malnutrition associated.

Front 42

Mucormycosis location and diagnosis

Back 42

Ubiquitous in nature.
Diagnosis usually made via detection of non-septate hyphae post mortem.
Can Culture - looks wooly rapidly filling entire plate.

Front 43

Pneumocystis jurovecii infection and disease

Back 43

1) Probably airborne transmission
2) Systemic opportunistic. Causes pneumonia in immunocompromised especially HIV. Hypoxemia is a hallmark.

Front 44

Pneumocystis jurovecii location and diagnosis

Back 44

Ubiquitous in nature. Diagnosed via direct microscopy. Can be seen via Calcoflur white stain or GMS stain. Cannot be cultured.