FINAL EXAM Flashcards
List the asexual and sexual spores of fungi and give an example of an organism which exhibits each type
Asexual:
arthrospores, blastospores, chlamydospores
Sexual:
ascospore, basidiospores, zygospore
Identify the fungus: Thick-walled, broad-based yeast
Blastomyces dermatiditis
Identify the fungus: Spherules filled with endospores
Coccidioides imitis
Identify the fungus: Thick-wall barrel-shaped arthrospores
Coccidioies imitus
Identify the fungus:
Spiny tuberculate macroconidia
Histoplasma capsulatum
Identify the fungus:
Brown sclerotic bodies
Chromomycoses dematiaceous fungi
Identify the fungus:
Thick-walled, spindle-shaped macroconidia
Microsporum canis
Identify the fungus:
Colony has a red reverse
Trichophyton rubrum
Identify the fungus:
Thin-walled, club-shaped macroconidia in clusters
Epidermophyton
Identify the fungus:
Produces germ tube
Candida albicans
Identify the fungus:
Causes epidemic scalp ringworm
Trichophyton tonsurans
Identify the fungus:
Broad, non-septate hypae in tissue
Mucor or rhizopus
Identify the fungus:
Brown, gritty deposits in sputum
Aspergillus
Identify the fungus:
Multiple buds in tissue
Paracoccidioides
Identify the fungus:
Causes Phycomycoses
Mucor or rhizopus
List the species of rickettsia, their mode of transmission (vectors), and the diseases they
cause.
Only important one to know: Rocky Mountain spotted fever, deer tick, Rickettsia rickettsii
How do rickettsia differ from chlamydia?
rickettsia need an arthrodpod vector
What diseases are caused by chlamydia and how are thy spread?
psittacosis
aerosol
Which viruses are indicted by:
Burkitt’s lymphoma
Epstein-Barr
Which viruses are indicted by:
Infectious mononucleosis
Epstein-Barr
Which viruses are indicted by:
Large, red intranuclear inclusions
Cytomegalovirus
Which viruses are indicted by:
Negri bodies
rabies
Which viruses are indicted by:
Shingles
varicella zoster
Define Definitive host
host in which sexual stage of life cycle occurs; adult
Define Intermediate host
host in which asexual stage of life cycle occurs;larval stage
Define Reservior host
animals other than man
List the four classes of protozoa and their means of motility
Sarcodina-pseudopods
Ciliata-cilia
Mastigophora-flagella
Sporozoa-non motile
What protozoan is indicated by:
Sluggish random motility
Entamoeba coli
What protozoan is indicated by:
Fine, even peripheral chromatin
Entamoeba histolytica
What protozoan is indicated by:
Oval cyst has large, blot-like karyosome
Endolimax nana
What protozoan is indicated by:
Large glycogen vacuole stains deeply with iodine
Iodamoeba butschlii
What protozoan is indicated by:
Lacks a cyst form
Dientamoeba fragilis, Trichomonas vaginalis, Entamoeba gingivallis
What protozoan is indicated by:
Troph is bilaterally symmetrical
Giardia lamblia
What protozoan is indicated by:
Pear-shaped troph with jerky motility is found in urine
Trichomonas vaginalis
What protozoan is indicated by:
Cyst is lemon-shaped with “nipple” on end
Chillomastix mesnili
How are most protozoan diseases transmitted?
fecal-oral ingest the cyst
What morphological form of the blood and tissue flagellates is intracellular?
LD body or leishmanial forms
Which species exist in this form in human cells?
All Leishmania and Trypanosoma cruzii
List the major species of Leishmania and Trypanosoma, the diseases they cause, and their vectors
Trypanosoma gambiense- West African sleeping sickness, tsetse fly Leishmania donovani-Kala-azar, LD bodies, sand flies(phlebotomis)
Leishmania braziliensis-espundia, sand flies
Leishmanis tropica-oriental sore, Baghdad/Delhi boil, sand flies
chagas disease Trypanosoma cruzii kissing bug
Describe the principle and interpretation of the Sabin-Feldman dye test
In a positive test, Toxoplasma gondii will not take up the dye. In absence of the antibodies it will stain blue
What is the first intermediate host of all human flukes?
snails
What species of fluke is indicated by:
Usual parasite of sheep has an extremely large egg
Fasciola hepatica
What species of fluke is indicated by:
Largest fluke found in man
Fasciolopsis buski
What species of fluke is indicated by:
Ova often confused with Diphyllobothrium latum
Paragonimus westermani
What species of fluke is indicated by:
Egg has prominent shoulders and resembles a light bulb
Clonorchis sinensis
What species of fluke is indicated by:
“Bladder fluke” associated with bladder cancer
Schistosoma hematobium
What species of fluke is indicated by:
Ova can appear in the stool or sputum
Paragonimus westermani
Define hydatid cyst
larval stage of Echinococcus granulosis; tapeworm larvae large bladder filled cyst
Define proglottid
individual segments of a tapeworm
Define neck
narrowest part of the tapeworm, located just behind the scolex
Define rostellum
fleshy extension of scolex that has 1 or 2 rows of hooks
Define scolex
head of a tapeworm may have suckers (4), bothria (2) or hooks; organ for attachmen
Define strobila
general term for entire tapeworm
List the definitive host, the intermediate host, the diagnostic stage, and the infective stage:
Diphyllobothrium latum
Definitive host: man
Intermediate host: freshwater fish
Diagnostic stage:egg
Infective stage: plerocercoid
List the definitive host, the intermediate host, the diagnostic stage, and the infective stage:
Taenia saginata
Definitive host: man
I
ntermediate host: cow
Diagnostic stage: egg
Infective stage: cysticercus bovis
List the definitive host, the intermediate host, the diagnostic stage, and the infective stage:
Taenia solium
Definitive host: man
Intermediate host: pig
Diagnostic stage:egg
Infective stage: cysticercus cellulosae
List the definitive host, the intermediate host, the diagnostic stage, and the infective stage:
Hymenolepis nana
Definitive host: man
Intermediate host: none
Diagnostic stage: egg
Infective stage: fully embryonated egg
List the definitive host, the intermediate host, the diagnostic stage, and the infective stage:
Hymenolepis dimunata
Definitive host: rat
Intermediate host: grain beetle, flea
Diagnostic stage:egg
Infective stage: cystercoid
List the definitive host, the intermediate host, the diagnostic stage, and the infective stage:
Echinococcus granulosus
Definitive host: canines
Intermediate host: sheep
Diagnostic stage: hydatid cyst which is found in man
Infective stage: egg
How can Taenia saginata and Taenia solium be differentiated?
eggs of each are indistinguishable. Uterus of T. solium has only 7-15 lateral branches. T. saginata has more uterine branches, no hooks on scolex.
Man can be infected by T. solium eggs but not by T. saginata eggs
How can Hymeolepis nana and Hymenolepis dimunata be differentiated?
H. diminuta eggs are larger and have no polar filaments
Which one is the “dwarf tapeworm”?
Hymenolepsis nana
What are spicules?
associated in nematode with ejaculating duct-necessary for reproduction
How does the life cycle of nematodes differ from that of trematodes (in general)?
nematodes have a more simple life cycle, 1 host and external environment, alternate between free living and parasitic
trematodes have at least 1 if not 2 intermediate hosts
List the definitive host, intermediate host (if present) the diagnostic stage (include appearance), infective stage, and any appropriate common names:
Ascaris lumbricoides
Definitive host: man
Intermediate host: none
Diagnostic stage: egg
Infective stage: embryonated egg
Common Name: roundworm
List the definitive host, intermediate host (if present) the diagnostic stage (include appearance), infective stage, and any appropriate common names:
Enterobius vermicularis
Definitive host: man
Intermediate host: none
Diagnostic stage: egg
Infective stage: embryonated egg
Common name: pinworm*
List the definitive host, intermediate host (if present) the diagnostic stage (include appearance), infective stage, and any appropriate common names:
Necator americanus
Definitive host: man
Intermediate host: none
Diagnostic stage: egg
Infective stage: filariform larvae
Common name: hookworm
List the definitive host, intermediate host (if present) the diagnostic stage (include appearance), infective stage, and any appropriate common names:
Strongyloides stercoralis
Definitive host: man
Intermediate host: none
Diagnostic stage: rhadbitiform larvae
Infective stage: filariform larvae
Common name: threadworm
List the definitive host, intermediate host (if present) the diagnostic stage (include appearance), infective stage, and any appropriate common names:
Trichinella spiralis
Definitive host: man
Intermediate host: pig
Diagnostic stage: encysted larvae
Infective stage: encysted larvae in muscle
Ccommon name:
pork tapeworm
List the definitive host, intermediate host (if present) the diagnostic stage (include appearance), infective stage, and any appropriate common names:
Trichuris trichiuria
Definitive host: man
Intermediate host: none
Diagnostic stage: egg
Infective stage: embryonated egg
Common name: whipworm
How can the rhabditiform larvae of hookworm and Strongyloides be differentiated?
rhabditiform (N. americanus)- long buccal cavity
strongyloides-short buccal cavity
How are infections due to these organisms usually acquired?
penetration of skin by filariform larvae
In the life cycle of Strongylodies, what do the terms autoinfection, direct development, and
indirect development refer to?
person infects themselves; like hookworm rhabditifom directly develops into filariform ; rhabditiform develops into a free living adults
What is visceral larval migrans and what is it caused by?
Toxocara canis
Cutaneous larval migrans (or “creeping eruption”)
Ancylostoma braziliense
List several species of protozoa or helminths which can be diagnosed by observation of a stained blood smear
plasmodium, trypanosome, leishmania, microfilarial larva (Brugia)
List several distinctive features of filarial worms
presence of nuclei helps to id larvae born alive. some have sheath derived from eggshell, have periodicity; female gives birth to live larvae
How do Wuchereria bancrofti and Brugia malaya differ?
both cause elephantiasis and live in lymphatic system.
*BRUGIA HAS A MUCH HIGHER NUMBER OF MICROFILARIA IN THE BLOODSTREAM
bancrofti is sheathed and Malaya is not
Malaya has more microfilarial larvae
List the intermediate host, the specimen needed for diagnosis, the disease caused, and the diagnostic stage (including description) for the following: Brugia malaya
Intermediate host: mosquito
Specimen needed for diagnosis: blood
Disease caused: elephantiasis
Diagnostic stage: microfilaria
List the intermediate host, the specimen needed for diagnosis, the disease caused, and the diagnostic stage (including description) for the following: Dracunculus medinnesis
Intermediate host: Cyclops/copepod
Specimen needed for
Diagnosis: skin
Disease caused: dracunculosis
Diagnostic stage: rhabditiform larvae
List the intermediate host, the specimen needed for diagnosis, the disease caused, and the diagnostic stage (including description) for the following: Loa loa
Intermediate host: chrysops fly (deer fly)
Specimen needed for
Diagnosis: blood
Disease caused: loiasis (severe eye disease)
Diagnostic stage: microfilaria
List the intermediate host, the specimen needed for diagnosis, the disease caused, and the diagnostic stage (including description) for the following: Onchocerca volvulus
Intermediate host: simulium fly (black fly)
Specimen needed for
Diagnosis: skin
Disease caused: river blindness
Diagnostic stage:
microfilaria
List the intermediate host, the specimen needed for diagnosis, the disease caused, and the diagnostic stage (including description) for the following: Wuchereria bancrofti
Intermediate host: mosquito
Specimen needed for
Diagnosis: blood
Disease caused: elephantiasis
Diagnostic stage:microfilaria
If an ova and parasite exam can not be performed right away, what procedure should be followed
perform quick macro and micro exam, add preservative and refrigerate within 30 min.
What preservative is usually used for the trichrome stain?
PVA
What is the main use of a permanent stained smear?
to see protozoan cysts and trophs
List the two major concentration procedures and the principle of each
formalin ether- sedimentation
zinc sulfate-flotation
What is the specific gravity of the solution employed in the floatation method
1.18
If negative results were obtained using the zinc sulfate method, what would be the best course to follow if the doctor still felt the patient had a parasitic disease?
Repeat using formalin ether
What parasite often causes pneumonitis in children?
Ascaris
In which two parasitic infections is autoinfection most common?
Pinworm, strongylodies
List several species of parasites which can be transmitted by contaminated drinking water
E. histolytica, all schistosomes (not HOOKWORMS)
List several environmental or climatic factors which are important in the spread and/or prevention of parasitic infections
temp, sand, soil, controlling insect population, water filtration
Make sure you know the scientific names of the organisms we studied that have the following common names:
Bilhariasis
any schistosome (Schistosoma sp.)
Make sure you know the scientific names of the organisms we studied that have the following common names:
Blackwater fever
Plasmodium falciparum
Make sure you know the scientific names of the organisms we studied that have the following common names:
Guinea worm
Dracunculus medinensis
Make sure you know the scientific names of the organisms we studied that have the following common names:
Thread worm
Strongyloides stercoralis
Make sure you know the scientific names of the organisms we studied that have the following common names:
eye worm
Loa Loa
Make sure you know the scientific names of the organisms we studied that have the following common names:
Whipworm
Trichuris trichiura