Intensive Recap

Question 1

In a patient with diarrhea, occasionally E. histolytica (4 nucleated cysts, no chromatoidal bars) are identified as being present; however, these cells, which are misdiagnosed as protozoa, are really:

Answer 1

PMN leukocyes

Question 2

Rhabditoform larva with purposeless motion and short buccal cavity:

Answer 2

Strongyloides

Question 3

The term INTERNAL AUTOINFECTION is generally used in referring to infections with:

Answer 3

S. stercoralis

Question 4

The mouth of Necator americanus is characterized by the presence of:

Answer 4

Cutting plates

Question 5

Microcytic anemia is assoc. with this parasite:

Answer 5

Ancylostoma duodenale

Question 6

The infective stage is the sheathed filariform larva:

Answer 6

Ancylostoma duodenale

Question 7

Habitat of adult Trichinella spiralis:

Answer 7

Small intestines

Question 8

Which of the following microfilariae is unsheathed?

Answer 8

Onchocerva volvulus (skin snips; stained by Giemsa or H and E)

Question 9

Suitable specimen for the ID of microfilaria:

Answer 9

Blood

Question 10

Technique to best diagnose microfilaria while still visible in the PB:

Answer 10

Knott’s technique

Question 11

Visceral larva migrans is assoc. with this organism:

Answer 11

T. canis

Question 12

Charcot Leyden crystals in stool may be assoc. with an immune response and are thought to be the breakdown products of:

Answer 12

Eosinophils

Question 13

Nematode parasite thought to have been the “fiery serpent” of the ancient parasites. This parasite, which has various species of Cyclops as its IH, is:

Answer 13

Dracunculus medinensis

*Medicine - Rod of Asclepius

Question 14

A dog parasite that almost never develops to an adult in human has been found in some persons as a cause of a subcutaneous nodule or a solitary peripheral nodule in the lung. This nematode is:

Answer 14

D. immitis

Question 15

The adult female is characterized by having a barber’s pole appearance due to ghe loopong of the whitish uterus around the reddish digestive tract:

Answer 15

Angiostrongylus cantonensis

Question 16

Operculated ovum containing a miracidium and can appear in sputum, often accompanied by blood and Charcot-Leyden crystals:

Answer 16

Paragonimus westermani

Question 17

Infetive stage of the Schistosomes to their final host:

Answer 17

Cercaria

Question 18

Which of the following organisms penetrates the skin, is endemic in Africa and the Middle Easy, has large terminal spine on its eggs, and is found in urine sample:

Answer 18

S. haematobium

Question 19

Cysticercosis is caused by the disseminated larve of:

Answer 19

T. solium

Question 20

In some individuals, this worm can cause a megaloblastic anemia:

Answer 20

D. latum

Question 21

A 45 y/o male sheepherder in California presents with “hepatitis”. Since other criteria are not met, X-ray-angiography was performed of the abdomen with the results that a tumor-like body is revealed within the love. Bc of his occupation, a Casoni test is peformed and found (+). Surgical removal of this “tumor” reveals a large cyst full of hydatid sand. What is the most likely etiologic agent involved in this infection?

Answer 21

Echinococcus granulosis

Question 22

What trophozoite is distinguished by the posession of achromatic granules surrounding its karyosomal chromatin?

Answer 22

Iodamoeba butschlii

Question 23

What is the most dependable procedure for the accurate, specific diagnosis of an intestinal amebic infection?

Answer 23

Permanently stained smear

Question 24

A soil and water amoeba isolated from cases of meningoencephalitis:

Answer 24

Naegleria

Question 25

The method of choice to detect Acanthamoeba spp. from corneal ulcer acrappings is:

Answer 25

BAP flooded with a 24H grow of E. coli

Question 26

A protozoan organism the has been implicated in water borne and food borne outbreaks. The suspected organism is:

Answer 26

G. lamblia

Question 27

The string test (Entero-Test) for obtainin a small specimen of duodenal contents for parasitic infection would be most appropriate for:

Answer 27

G. lamblia

Question 28

A 15 y/o male return from a summer in Paraguay ina village infested with reduvid bugs and presents with fever. Based on his recent travel history, a Giemsa-stained BS analysis is performed and shows presence of parasites. What is the most likely etiologic agent involved in this infection?

Answer 28

T. cruzi

Question 29

Xenodiagnosis is usually peformed for the diagnosis of:

Answer 29

T. cruzi

Question 30

Asexual life cycle of malaria parasite occur in:

Answer 30

Man

Question 31

Plasmodium spp. which has an affinity for mature or older RBCs:

Answer 31

P. malariae

Question 32

Stage predominantly seen in the smear is the band form of developing trophozoite:

Answer 32

P. malariae

Question 33

Which spp. of Plasmodium can have erythrocytic stages capable of causing relapses months or years after initial infection?

Answer 33

P. ovale

Question 34

Which of the following statements is correct for Plasmodium falciparum?

Answer 34

✅ Infection is commonly known as Maligtant Tertian Malaria ✅ Tiny ring forms, multiple infected RCs and "accole" rings ✅ Granulocytes are cresent shaped

Question 35

The observation of piroplasts in packets of 2 to 3 or a Maltese cross formation in stained BF most likely indicates:

Answer 35

Babesia microti

Question 36

The demonstration of chorioretinitis and cerebral calcifications in a mewborn would result in which of these laboratory request?

Answer 36

Titer of Toxoplasma Abs

Question 37

What constitutes a positive result in the Sabin-Feldman dye test?

Answer 37

Toxoplasma loses its affinity for methylene blue dye

Question 38

The modified acid-fast stain is most often used in parasitology to ID:

Answer 38

Cryptosporidium and other coccidia

Question 39

Oocysts of Cryptosporidium parvum can be detected in stool specimens using:

Answer 39

Modified Ziehl-Neelsen acid-fast stain

Question 40

The ideal temperature to hold a fecal specimen for more then 1 hour is:

Answer 40

Refrigerator temp.

Question 41

The procedure that determines the number of eggs per gram of feces is:

Answer 41

Stoll's dilutiom technique