Term
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Definition
poisonous mushrooms;
have toxins (amatoxin, phallotoxin) that target the Liver |
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Term
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Definition
have Aflatoxins -- potential carcinogens
related to grain storage - peanuts, maize, corn, etc... in developing countries |
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Term
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Definition
a superficial mycoses (only in dead epidermis layers, non-invasive)
brownish spots where there are sebbaceous glands (where there is hair) back/chest
(caused by malassezia furfur) |
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Term
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Definition
a superficial mycoses
brownish discolorations
on palms and soles of feet
(caused by Hortaea werneckii) |
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Term
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Definition
a superficial mycoses (only on dead cells)
white or black stuff on hair shaft
stiff hair |
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Term
Cutaneous mycoses
where are they?
what are they caused by?
what are the three genusi of fungus that cause these? |
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Definition
keratized layers of epidermis
caused by dermatophytes -- Non-invasive molds
within the dermatophyte genera there are Trichophyton, Microsporum, and Epidermophyton, or a combination of these three genuses that cause cutaneous mycoses |
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Term
Tinae pedis
Tinae cruris
Tinae barbae
Tinae corporus |
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Definition
cutaneous mycoses
caused by dermatophytes (Trichophyton likely)
althletes foot
jock itch
beard fungus
fungus on the body |
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Term
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Definition
cutaneous mycosis
caused by dermatophytes (e.g. Trichophyton)
likes the toe nail |
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Term
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Definition
cutaneous mycosis
caused by dermatophyte (e.g. Microsporum canis)
inflammation of the scalp follicles
Kerion = site of HAIR LOSS |
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Term
| lymphocutaneous sporotrichosis |
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Definition
Subcutaneous mycosis (soil and vegitation trauma, reaches deep dermis, hypodermis and muscle/bone)
nodules along lymphatics
occupational disease -plants, thorns |
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Term
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Definition
Subcutaneous (past derm, trauma)
flowery-Cauliflower-like appearance
1 month to 20 year inoculation
caused by lack of protective footwear in tropic soil or organic matter |
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Term
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Definition
Subcutaneous infection
results after trauma in tropical plant debris
movable masses by shoulders/pelvis/hip |
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Term
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Definition
-Candida is part of normal flora;
-It is a YEAST at warm/body temp. (and MOLD at other temps...)
-ablicans is most common candida, then candida glabrata, then candida krusei
GERM TUBE-Grow yeast at 37C, you can identify the candida albicans by Germ Tube (hyphal outgrowth charachteristic of mold)
ADHERENCE-integrin-like molecules allows adherence/fibronectin binding/invasion of mucosal cells |
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Term
Candida albicans
(diseases) |
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Definition
It is Opportunistic
Infant Oral Thrush and diaper rash (develops if infected with Candida before bacterial normal flora)
Cutaneous candidiasis in adults (warm skin folds and nails)
Vaginal (mucosal) candidiasis - happens when balance of normal flora is disrupted (pregnancy, contraceptives, antibiotics, corticosteroid treatment)
Oral Mucosal Candidiasis (AIDS patients)
Systemic candidiasis (from indwelling catheters, IV's, nosocomial bloodstream infection)
Chronic Mucocutaneous Candidiasis (lifetime; genetically impaired T cell response) |
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Term
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Definition
P jirovecii is in humans
like a fungus --it has chitin
like a protozoan --it is not susceptible to anti-fungals
Lung cyst spits out 8 sporozoites - which become trophozoites - and grow into cysts again (cycle)
Pneumocystis is an opportunistic infection -- progressive fluid and ASPHYXIA |
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Term
| definition of systemic mycoses |
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Definition
NOT part of NORMAL FLORA
they are Geographic Opportunistic infections
they start in lung
they get into other organs (secondary organ tropism) |
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Term
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Definition
systemic mycosis
geographically found in Mississippi/Ohio River area (80-90% of residents)
found in bird or bat soil; birds are infected (high N content)
intracellular growth in phago macrophages/bone marrow mononuclear cells/retina/eye lining (i.e. they infect the Reticuloendothelial system) |
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Term
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Definition
systemic mycosis
geographically found in isolated desert soil (valley fever, desrt rheumatism)
large spheres in lung
can see skin lesions if systemic |
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Term
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Definition
systemic mycosis
found worldwide
bird droppings are high in N (birds themselves aren't infected)
Most common cause of FUNGAL Meningitis
(Encapsulated YEAST (body temp) in brain tissue / Antigens in cerebrospinal fluid)
india ink test - separates this yeast from other mycoses |
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Term
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Definition
systemic mycosis (starts in lung)
not quite as prevalent as Histoplasma capsulatum
skin lesion, like the ones seen on dogs |
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Term
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Definition
systemic mycosis
found in air duct of hospitals (nosocomial)
fungus ball in lung
line blood vessels
dark area in brain
(Aspergillus flavus - Aflatoxin:
potential carcinogen; in grain storage)
Invasive Septated 45 degree/parallel Hyphae molds |
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Term
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Definition
systemic zygomycosis, as opposed to Subcutaneous;
systemic zygomycosis happens in hospitals, organ transplants, immunosuppression
Mucor is a common genus of Zygomycoses;
Invasive Non-septated hyphae 90 degree (non-parallel) molds |
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Term
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Definition
Poly"ene" (lipophilic), binds to ergosterol -- messes up membrane
drug of choice, covers almost everything (except Pseudallescheria boydii)
- candida
- cryptococcoal meningitis
- Mucormycosis (zygomycosis - invasive, nosocomial, non-parallel molds)
more expensive lipid formulas are less renal-toxic than less expensive convensional drug (if creatinine rises, don't adjust to renal function, just switch to more expensive kind) |
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Term
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Definition
| with amphotericin for initial therapy of cryptococcal meningitis |
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Term
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Definition
Azole (inhibit synthesis of ergosterol; doesn't bind it)
Covers YEASTS (Candida, Cryptococcus)
- drug of choice for candida esophagitis (yeast in esophagus).
- However, candida glabarata is sometimes resistant, candida krusei always resistant -- don't use if expecting resistance
- takes over therapy for Cryptococcus meningitis after two weeks of Ampho B/5FC |
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Term
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Definition
Azole (inhibits ergosterol synthesis), first one to treat Aspergillus
- used for endemic mycoses (sporo, histo, blasto, etc...) |
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Term
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Definition
Drug of choice (oral) for Aspergillus (invasive parallel mold; grain storage aflatoxin/ hospital systemic)
visual side-effects |
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Term
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Definition
| Azole, first that can treat both Aspergillus and Mucor (invasive non-parallel molds) |
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Term
Echinocandin, the class
Caspofungin, the main drug |
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Definition
act at Rigid Cell Wall (not on ergosterol)
Aspergillus and Candida-especially
- Aspergillus salvage therapy
- Candidemia, candida esophagitis
non-toxic but in IV for a long time
Newer Echinocandins: Mucafungin, Anidulafungin; approved for candida |
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Term
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Definition
Candida
- Amphotericin for serious candida (endocarditis, meningitis, etc...)
- Fluconazole used for Candida esophagitis/candidemia (unless the Candida is resistant candida krusei or neutropenic patient)
- Echinocandins can be very useful for Candida (candidemia, candida esophagitis)
Cryptococcus
- Amphotericin B with Flucytosine, Switch to Fluconazole for Cryptococcus meningitis |
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Term
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Definition
Histoplasmosis (ohio/mississippi)
Blasto dermatitidis (ohio/mississippi-dogs)
Coccidiodies immities (desert)
Sporotrichosis (thorn bushes)
histo/blasto meningitis - Ampho B
sporotrichosis, non-serious endemics (histo/blasto) -- use Itraconazole |
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Term
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Definition
Invasive Mold (Aspergillus-like parallel 45 hyphae)
- Voriconazole is drug of choice (compared to Ampho B)
- Caspofungin salvage therapy
- Honorable mention: Itraconazole first AZOLE to treat Aspergillus and Aspergillus-like Pseudallescheria boydii (boydii= almost only hole in Ampho B coverage)
Invasive Mold (Mucor/Zygomycoses Non-parallel 90 hyphae)
- Ampho B
- Honorable mention: Posaconazole for mucor (new/not well studied yet)
Invasive Mold or Pulmonary Nodules
- Ampho B -- covers both Invasive types, Aspergillus types and Mucor types
- Voriconazole/Caspofungin -- covers Aspergillus types
- Posaconazole - not well studied |
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Term
| Non-invasive Mold Treatment |
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Definition
for dermatophytes
miscellaneous drugs - terbinafine, tolnaftate; Some Azoles (miconazole, clotrimazole, ketoconazole)
Itraconazole used as pulse therapy for onychomycosis |
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Term
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Definition
Rhizopods (Amoebae)
fecal oral invaders, makes flask shape in wall
numerous bloody stools daily |
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Term
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Definition
flagella
most common intestinal protozoa in US
cyst/trophoite feeding stages (cyst for protection until ingested)
only 10-25 cysts is minimum dose
stool may contain up to 300 million |
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Term
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Definition
flegella
no cysts
sexual transmission |
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Term
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Definition
sporozoa non-motile sexual(sporogony)/asexual(schizogony)
problem for immunocompromised pateints, can
reactivate latent toxoplasma (multifocal encephalitis)
cat litter dust)** leads to fetus damage |
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Term
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Definition
sporozoa non-motile sexual/asexual
on microvilli, but non-invasive
watery diarrhea, Milwakee 93 |
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Term
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Definition
sporozoa non-motile sexual/asexual
infects blood and tissues
Misquito bite (SEXUAL repro in Misquito)
merozite enters RBC's (forma dark ring)
liver latent
(Asexual repro in blood/liver)
misquitos eat gamete
sporozoites infect Miquito Salivary glands
there are four species - one strain of malaria
- four strains of Malaria
- 2-3 million annual deaths --100 during lecture --major killer of travellers, children, soldiers overseas |
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Term
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Definition
flagella
II. Trypanosoma sp. includes three major pathogens, T. cruzi, T. gambiense, and T. rhodesiense
A. General properties of T. cruzi
1. Life cycle involves the reduviid bug as the vector and both humans and animals (including cats and dogs as well as raccoons and rats) as reservoir hosts.
2. Insects ingest blood from host that contains trypomastigotes. In the insect gut these differentiate into epimastigotes and then into trypomastigotes. When the bug bites again, the site is contaminated with feces containing trypomastigotes, which enter the blood of the person.
B. Pathogenesis and immunity of T. cruze
1. T. cruze causes Chagas’ disease seen primarily in Central and South America, rarely in USA
2. Cardiac muscle is the most frequently affected tissue.
C. Clinical manifestations of T. cruze
1. Acute phase of Chagas’ disease consists of facial edema and a nodule near the bite with fever, lymphadenopathy and hepatosplenomegaly. Acute phase lasts for 2 months.
2. Chronic form includes myocarditis.
D. General properties of T. gambiense and T. rhodesiense
1. These two organisms cause sleeping sickness.
2. The vector is the tsetse fly
3. The 3-week life cycle in the tsetse fly begins with ingestion of trypomastigotes in a blood meal from the host. The organisms multiply and develop in the gut and move to the salivary glands. From here they are injected into the bloodstream during the insect bite
4. These trypanosomes exhibit remarkable antigenic variation of their surface glycoproteins, which allows the organism to continually evade the host’s immune response.
E. Pathogenesis and epidemiology of T. gambiense and T. rhodesiense
1. Trypomastigotes spread from the skin through the blood to the lymph nodes and the brain
2. Sleeping sickness can progress to a coma as a result of a demyelinating encephalitis.
3. In the acute form, a cyclical fever spike occurs every 2 weeks due to antigenic variation.
4. Disease is endemic in sub-Saharan Africa |
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Term
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Definition
GI Parasites
General properties of the helminthic worms which include nematodes, cestodes and trematodes |
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Term
| nematode Enterobius vermicularis |
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Definition
Enterobius vermicularis
A. Is a nematode that causes pinworm infections
B. General properties
1. The life cycle is confined to humans and the infections are acquired by ingesting the worm eggs.
2. Eggs hatch in the small intestine where the larvae differentiate into adults and migrate to the colon. At night the female migrates to the anus and releases thousands of fertilized eggs on the perianal skin. Within 6 hours, the eggs develop into larvae and become infectious. Reinfection can occur if they are carried to the mouth by fingers after scratching the itching skin.
C. Pathogenesis and clinical manifestations
1. Perianal pruritus is the most common symptom and is due to the allergic reaction to the presence of either the adult female or the eggs.
2. Disease is seen worldwide and is the most common helminth infection in the USA.
3. Children younger that 12 years are the most commonly affected group.
D. Laboratory diagnosis
1. Eggs are recovered from perianal skin by using Scotch tape and observed microscopically.
2. Eggs are not found in the stools
3. The adult worms can be found in the stools or near the anus of diapered children. |
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Term
| nematode Ascaris lumbricoides |
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Definition
A. Referred to at the “giant nematode” and causes ascariasis
B. General properties
1. Humans are infected by ingesting worm eggs in food or water contaminated with human feces
2. The eggs hatch in the small intestine, the larvae migrate through the gut wall into the blood stream and then to the lungs. They enter the alveoli, pass up the bronchi and trachea, and are swallowed.
3. Within the small intestine they become adults and live in the lumen, existing on ingested food.
4. The adults are the largest intestinal nematodes growing to 25 cm or more.
5. Thousands of eggs are laid daily and are passed in the feces and form embryos in the warm, most soil. Ingestion of the embryonated eggs completes the cycle.
C. Pathogenesis and clinical manifestations
1. Major damage occurs during larval migration
2. The principal site of tissue reaction is the lung.
3. Since the adult worms derive their nourishment from ingested food, a heavy worm burden may contribute to malnutrition
4. May see Ascaris pneumonia with heavy larval burden, and obstruction from the presence of adult worms in the intestine
D. Epidemiology
1. Infection is very common, especially in the tropics where hundreds of millions of people are infected.
2. Most cases in USA are in southern states. |
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Term
| nematode Necator americanus |
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Definition
A. Causes hookworm infection
B. General properties
1. Humans are infected when larvae in moist soil penetrate the skin, usually the feet or legs
2. The larvae are carried by the blood to the lungs, migrate into the alveoli and up the bronchi and trachea, and then swallowed.
3. They develop into adults in the small intestine and attach to the wall with hooks and feed on blood from the capillaries of the intestinal villi.
4. Thousands of eggs per day are passed in the feces, which develop, into larvae to start the cycle again.
C. Pathogenesis and clinical manifestations
1. The major damage is due to the loss of blood at the site of attachment in the small intestine.
2. Weakness and pallor accompany the microcytic anemia callused by the blood loss.
3. Pneumonia can be seen during larval migration through the lungs.
D. Epidemiology
1. Infection is worldwide, especially in tropical areas. In USA the infection is endemic in the rural southern states.
2. Walking barefooted on soil predisposes one to infection. |
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Term
| nematode Trichinella spiralis |
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Definition
A. Causes trichinosis
B. General properties
1. Any mammal can be infected; however, pigs are the most important reservoir of human disease in USA (bears in Alaska)
2. Infected by eating raw or undercooked meat containing larvae encysted in the muscle.
3. The larvae excyst and mature into adults within the mucosa of the small intestine.
4. The larvae are released and enter bloodstream to many organs; however, they develop only in striated muscle cells.
5. Humans are end-stage hosts
C. Pathogenesis and clinical manifestations
1. A few days after eating the undercooked contaminated meat, the patient experiences diarrhea followed 1-2 weeks later by fever, muscle pain, periorbital edema, and eosinophilia.
2. Signs of cardiac and central nervous system disease are frequent since larvae also migrate to these tissues.
D. Epidemiology
1. Disease occurs worldwide, especially in eastern Europe and west Africa
2. In USA, generally associate with eating home-prepared sausage, usually from farms where pigs are fed uncooked garbage. |
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Term
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Definition
VII. Cestodes: Tapeworms.
A. Have two main structural components, a rounded head called a scolex and a flat body of multiple segments called proglottids.
1. The scolex attaches to the intestinal wall with suckers and hooks.
2. The worm grows by adding new proglottids from its germinal center next to the scolex. The oldest proglottids at the distal end are gravid and produce many eggs, which are excreted in the feces and transmitted to intermediate hosts such as cattle, pigs, etc.
B. Taenia solium: the adult form causes taeniasis and the larval form causes cysticercosis
1. In taeniasis, the adult tapeworm is located in the human intestine as a result of eating undercooked pork that contains the larvae, called cysticerci. The lavae attaches to the gut wall and take about 3 months to grow into adult worms measuring up to 5 meters in length. In the pig the embryos are carried in the skeletal muscle.
2. In cysticercosis, a person ingests the worm eggs in food or water contaminated by human feces. The eggs hatch in the small intestine and disseminate to many organs such as the eyes and brain.
3. The adult tapeworm causes little damage. Most patients with adult tapeworms are asymptomatic, but anorexia and diarrhea can occur. Cysticercosis in the brain causes headache, vomiting, and seizures.
4.
C. Taenia saginata is the beef tapeworm
1. Scolex has four suckers but no hooks.
2. Humans are infected by eating raw or undercooked beef containing larvae. In the small intestine the larvae attach to the gut wall and take about 3 months to grow into adult worms measuring up to 10 meters.
3. The proglottis detach, are passed in the feces and are eaten by cattle. The embryos emerge from the eggs in the cow’s intestine and are carried by the blood stream to skeletal muscle.
4. Little damage results from the presence of the adult worm in the small intestine.
5. The disease occurs worldwide but is endemic in Africa, South America and eastern Europe. Most cases in USA are imported. |
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Term
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Definition
trematodes that cause schistosomiasis
A. They have a sexual cycle in humans and asexual reproduction in freshwater snails.
B. General properties
1. They exist as separate sexes but live attached to each other. The female resides in a groove in the male where he constantly fertilizes her eggs.
2. Humans are infected when free-swimming fork-tailed cercariae that penetrate the skin. They then differentiate to larvae and enter the blood and reach liver and other organs.
C. Pathogenesis and epidemiology
1. Most of the pathologic findings are caused by the presence of eggs in the liver, spleen, or wall of the gut or bladder.
2. Eggs in the liver induce granulomas
3. To evade the host defense, the surface of schistosomes becomes coated with host antigens, therefore limiting the immune system to recognize them.
4. The epidemiology depends on the freshwater snails that serve as the intermediate host. Found in Africa and Latin America
D. Clinical manifestations
1. Most patients are asymptomatic, but chronic infections by become symptomatic and can cause morbidity and mortality.
2. Lakes in USA may contain “nonhuman” schistosomes that are incapable of replicating in humans and do not cause disseminated disease. However, they do cause “swimmer’s itch” which consists of pruritic papules which is an allergic reaction to the parasite. |
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