parasit.

Question 1

cryptosporidiosis diarrhea

Answer 1

profuse, water, self-limiting, more sever in AIDS

Question 2

cryptosporidiosis treatment

Answer 2

none

Question 3

crypstosporidiosis auto infection

Answer 3

20% thin wall cysts

Question 4

crypstosporidiosis stain

Answer 4

ziehl-nilsson, modified acid-fast smears(won’t see on trichrome)

Question 5

crypto/giardia dfa

Answer 5

fluorescent antibody test (use formalin), HIV services

most specific/sensitive

Question 6

cyclospora cayatanensis

Answer 6

fecal-oral FOOD and water, nausea diarrhea, anorexia

Question 7

parasitology autofluorescence

Answer 7

cyclospora (size important), isospora belli

Question 8

crypto/cyclo oocysts

Answer 8

crypto (8-10 um) cyclo (4-6 um)

Question 9

isospora bell

Answer 9

diarrhea, abdominal pain, ONLY COCCIDIAN PARASITE IN WHICH MAN IS DEFINITIVE HOST, oocysts not immediately infectious (unsporulated when passed)

Question 10

isospora diagnosis

Answer 10

zn- acid fast
auramine-rhodamine
oocysts best iseen in whet prep

Question 11

sarcocystis bovihominis/suihominis

Answer 11

cow and pig (wide range of mammalian and avian hosts (humans can be intermediate or definitive (multiplies asexually)

Question 12

micrsporidia

Answer 12

emerging infection of AIDS patients (obligate intracellular parasite) polar tubue-extrusion mechanism for injecting spore contents, NO OOCYST

Question 13

microsporidium genera

Answer 13

encephalitozoon, nosema, pleistophora, enterocytozoon, septatat, vittaforma, trachipleistophora (enterocytozoon bieneusi)

Question 14

microsporidia diagnosis

Answer 14

modified trichrome (belt-like stripe)
modified gram stain
giemsa
calcofluor

Question 15

microsporidia key points

Answer 15

30% of AIDS, modified trichrome difficult to interpret

mAB improve sens/spec.

Question 16

toxoplasma

Answer 16

ingestion of infective oocysts, or tissue cysts in meat, transplacental, blood transfusion, organ transplant
cat definitive host (excretes oocysts

Question 17

toxo stages

Answer 17

tachyzoites, bradyzoites, oocysts

Question 18

toxoplasma stain

Answer 18

giemsa

Question 19

toxo morphology

Answer 19

crescent shape, 2-3 x 4-8

bradyzoites in cysts seen with PAS stain (periodic acid Schiff)

Question 20

toxo serology

Answer 20

1: 16-1:64- past exposure/early disease
1: 256- recent exposure
1: 1024 significant infection

Question 21

pneumocystis jiroveci

Answer 21

disease: pcp
acquired: unknown environmental
leading cause of death in AIDS

Question 22

pneumocystis forms

Answer 22

cysts, sporozoites, trophozoites

cysts contain 8 sporozoites which mature into trophozoites, before encysting and repeating the cycle

Question 23

pneumo specimens

Answer 23

respiratory (sputum)
stain cyst: toluidine blue ) methenamine silver nitrate, crystal violet, calcofluor
Troph: Giemsa/WRight
DFA

Question 24

Naegleria fowleri

Answer 24

primary amoebic meningoencephalitis

acquired: water exposure (headache, vomiting, fever, confusion, seizures
site: CSF/brain (no other organ involvement)

Question 25

Naegleria fowleri morphology

Answer 25

trophozoites exist as amoebae or flagellate
trophozoite is infective
amoeboid stage has large karyosome
(no peripheral chromatin)

Question 26

naegleria flagellate

Answer 26

changes when transferred from culture or teased from tissue (2 flagella at broad end)

Question 27

Naegleria diag.

Answer 27

cannot differentiate from bacterial meningitis
must demonstrate amoebae in csf/tissue
examine csf for motile trophs
giemsa or wright

Question 28

Acanthamoebae Disease

Answer 28

granulomatous amebic encephalitis
keratitis
cutaneous/sinusitis
acquired: water exposure
site- eye, brain, cutaneous

Question 29

acanthamoeba morphology

Answer 29

no flagellate stage, cyst and troph found in tissue
troph- spiky pseudopodia
cyst- wrinkled outer wall (vs. Naegleria)

Question 30

acanthamoeba culture

Answer 30

e.coli overlay