Parasitology ID
Cryptosporidium
(lady bugs) stained with modified acid fast stain Oocyst 4-6um stain pink/red
Taenia saginata (proglottids)
Beef tape worm longer than wide 15-30 lateral uterine branches human is definitive host may grow up to 10-15 ft long w/ 2000 proglottidis
Trypanosoma cruzi
Chagas disease or South American Sleeping sickness
Opisthorchis (Clonorchis) sinensis (eggs)
Chinese Liver Fluke operculated small urn-shaped knob at one end
Reduvid Bug
Kissing Bug-Chagas-Trypanosoma cruzi
Schistosoma haematobium (egg)
Large egg has a delicate terminal spine lives in veins of urinary bladder causes hematuria
Schistosoma mansoni (egg)
Large egg with large lateral spine lives in portal veins of large intestine
Ascaris lumbricoides (eggs)
Largest nematode 130-300 mm lays up to 200,000 eggs daily eggs may be seen with whipworm infections eggs can be fertilized/unfertilized and corticated/decorticated
dientamoeba fragilis
NO CYST STAGE causes diarrhea 1-2 nuclei no visible flagella (but is a flagettate)
Hookworm (eggs)
Necator americanus (New World) & Ancylostoma duodenale species eggs cannot be distinguished from one another Causes anemia
Enterobius vermicularis (adult worm)
Pinworm
Enterobius vermicularis (egg)
Pinworm most common human parasite usually children DX with cellulose tape prep
Taenia solium (proglottids)
Pork tape worm -13 lateral uterine branches
Hymenolepis diminuta (eggs)
Rat tapeworm Man is accidental host by eating larva via an infected arthropod eggs can be confused with H. nana H. diminuta eggs are much larger and do not have polar filaments
Iodamoeba butschlii (cyst)
12 um 1 nuclei no peripheral chromatin Blot-like karyosome *Glycogen vacuole always present
Giardia lamblia (troph)
12 um pear or tear drop shaped 2 nuclei 4 pairs of flagella *falling leaf motility
Giardia lamblia (Cyst)
12 um in size very small oval cyst 4 nuclei and fibrils
Entamoeba histolytica (troph)
15-20 um 1 nuclei peripheral chromtin central karyosome finely granular cytoplasm & may contain ingested RBCs
Entamoeba coli (cyst)
15-25 um 8 nuclei periperhal chromatin eccentric karysome splintered-ended chromatoidal bars
Hookworm (rhabditiform)
2nd development stage for Hookworm larvae which may develop in stools left at RT has a long buccal cavity and no genitalia (vs. Strongyloides which is short & has genitalia)
Hookworm (filariform)
3rd development stage for hookworm pointed tail (vs. Strongyloides blunt notched)
Hymenolepis nana (eggs)
Dwarf tapeworm most common tapeworm in US eggs is slightly larger than Taenia species *Characteristic Polar Filaments
Diphylobothrium latum (proglottis)
Fish tapeworm wider than long uterus is rosette shaped Scolex has two longitunal grooves (botheria)
Trichuris Trichura (egg)
Whipworm eggs are barrel of football shaped with refractive polar plugs
Trichuris Trichura
Whipworm worms are 30-50mm long (2") human in only host
blastocystis hominis
can cause diarrhea
Fasciolopsis buski/hepatica (eggs)
cannot be differentiated, operculated eggs Buski-Giant Intestinal Fluke Hepatica-Liver Fluke
Entamoeba hartmanii (cyst)
less than 10um smaller than histolytica but looks similar
Strongyloides
looks very similar to hookworm, ID is made by examining the rhabditiform larvae or sometimes the filariform larve Rhabditiform-short buccal cavity and genitalia Filariform- notched tail
Chilomastic mesnili (cyst)
nonpathogenic Lemon or pear shaped 1 nuclei Curved cytosome (sheppards crook)
Entamoeba histolytica (Cyst)
round cyst 12-15 mm up to 4 nuclei peripheral chromatin present central karyosome chromitodal bars have rounded blunt ends
Taenia species (eggs)
round, thick shelled with radial striations with a six-hooked embryo *Saginata and solium cannot but differentiated at egg stage
Schistosoma japonicum (egg)
small lateral spine more knob like -not pointed lives in portal veins of small intestine
Endolimax nana (cyst)
smallest ameba 8um 4 very small nuclei No peripheral chromatin
Necator americanus (adult worm)
whipworm 12 um long *cutting plates (A. duodenale sp. have teeth)
Ancylostoma duodenale (adult worm)
whipworm 12 um long *teeth (N. amerianus has cutting plates