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