5.3 Micro

Question 1

Mycoses a/w birds

Answer 1

Histoplasmosis (bird, bat droppings)
Cryptococcus neoformans (pigeons)
Chlamydia psitacci (parrots)
Avian influenza
West Nile Virus

Question 2

What pts commonly get cryptococcal meningitis?

Answer 2

AIDS pts

Question 3

What is candida intertrigo?

Answer 3

Candida rash under breasts, in skin folds of obese pts

Question 4

What opportunistic fungal infection can penetrate the cribiform plate?

Answer 4

Mucor and Rhizopus

Get rhinocerebral and frontal lobe abscesses, can be deadly.

Question 5

Why are mucor and rhizopus mostly in DKA pts?

Answer 5

proliferates in blood vessel walls when there is excess ketone and glucose available.

(also common in leukemia pts, not for this reason)

Question 6

Onychomycosis

Answer 6

Fungal infection of nail bed
Caused by Tinea ungium
Rx griseofulvin (takes longer), terbinafin

Question 7

What mycoses might be seen in spelunkers?

Answer 7

Histoplasmosis (found in bird/bat droppings)

Question 8

Arthroconidia

Answer 8

Barrel-shaped form contained in Cocci

Some barrels are empty, allowing cocci to be light enough to be carried in air.

Question 9

What causes cauliflower skin lesions?

Answer 9

Blastomycosis

Question 10

List the antifungal meds

Answer 10

Amphotericin B
Nystatin
Azoles
Flucytosine
Caspofungin
Terbinafine
Griseofulvin

Question 11

What antifungal should be used for bad systemic infections?

Answer 11

Amphotericin B

Question 12

What is used to treat Sporothrix?

Answer 12

Itraconazole

Question 13

How do the azoles inhibit fungi?

Answer 13

Inhibit fungal ergosterol synth by inhibiting the P450 enz that converts lanosterol to ergosterol

Question 14

What hormones do azoles inhibit?

Answer 14

Corticosteroids, testosterone

can cause gynecomastia

Question 15

Gardnerella vaginalis vs Trichomonas vaginalis

Answer 15

Gardnerella = gram-neg bacteria causing vaginosis (not STD necessarily). Fishy, clue cells, not painful.

Trichomonas- protozoan (triangle-shaped) causing vaginitis- foul-smelling green discharge. Itching/burning.

Treat both with metronidazole.

Question 16

Most common protozoal infection in US

Answer 16

Trichomonas vaginalis or Giardia

Question 17

Which protozoa causes liver dmg?

Answer 17

Entamoeba histolytica- causes liver abscess.

Question 18

Malaria life cycle: looks like a diamond ring:

Answer 18

Trophozoite in RBCs

Question 19

Malaria life cycle: Ruptures cell host

Answer 19

Merozoite

Rupture causes fever cycles

Question 20

Malaria life cycle: replicates intracellularly

Answer 20

Schizont

Question 21

Malaria: cell form injected by Anopheles

Answer 21

Sporozoite

think of mosq injecting spores

Question 22

Malaria: banana shaped cell

Answer 22

Gamateocyte of plasmodium falciparum

Question 23

White patches on sides of tongues

Answer 23

might be candida, but if it’s on sides, may be Oral Hairy Leukoplakia- opportunistic infection by EBV!

Question 24

Causes endocarditis in IV drug users

Answer 24

Candida albicans

or S. epidermiditis

Question 25

Spaghetti and meatball appearance

Answer 25

Tinea versicolor

Question 26

What are fungal cell walls made of?

Answer 26

Ergosterol (fungi equivalent of cholesterol).

Ergosterol is inhibited by Terbinafine or the -azoles

Question 27

Cause of bacterial dysentery vs amoebic dysentery

Answer 27

Bacterial: shigella
Amoebic: Entamoeba histolytica

Question 28

In both strongyloides and ascaris, the eggs are coughed up/swallowed. How do they get into the body to begin with?

Answer 28

Stronglyoides: larvae in soil penetrate skin

Ascaris lumbricoides: eggs are ingested from contaminated food

Question 29

Worm in undercooked pork

Answer 29

Taenia solium

swiss cheese appearance of brain- can get seizures, altered mental status, coma, death

Question 30

Infection Leads to squamous cell carcinoma of bladder

Answer 30

Schisto hematobium