Flagellates, Ciliates, and Coccidia

Question 1

Dientamoeba fragilis trophozoite

Answer 1

7-12 um with considerable size and shape variation on single smear
1-2 nuclei, fragmented (3-5 granules) nuclear chromatin
No peripheral chromatin
Vacuolated cytoplasm
Progressive motility

Question 2

Answer 2

Dientamoeba fragilis trophozoite

Question 3

Trichomonas hominis trophozoite

Answer 3

5-15 um x 7-10 um
5 anterior flagella
Pyriform shape
Both axostyle and undulating membrane which extends entire length
Single nucleus

Question 4

Answer 4

Trichomonas hominis trophozoite

Question 5

Trichomonas hominis Pathology

Answer 5

Nonpathogenic

Question 6

Cryptosporidium species

Answer 6

Ovoid to spherical oocysts
5-6 um
small internal granules
Four slender, bow shaped sporozoites
Oocysts stain red with acid-fast stain

Question 7

Answer 7

Cryptosporidium species oocyst

Question 8

Giardia lamblia trophozoite

Answer 8

10-20 um x 5-15 um
Teardrop or pearshaped with posterior end pointed
Two sucking disks on ventral surface giving the face look to the organism
Motility is falling leaf

Question 9

Answer 9

Giardia lamblia trophozoite

Question 10

Giardia lamblia cyst

Answer 10

11-14 um x 7-10 um
Oval to round
Four nuclei
Axonemes and parabasal bodies may be evident
May see “halo” effect around outside on permanent stain
Googly eye appearance

Question 11

Answer 11

Giardia lamblia cyst

Question 12

Giardia lamblia Pathology

Answer 12

Diarrhea with increased fat and mucus secretions
Dehydration
weight loss
epigastric pain

Question 13

Diaentamoeba fragilis Pathology

Answer 13

Intermittant diarrhea and fatigue

Question 14

Trichomonas vaginalis trophozoite

Answer 14

12-26 um long
Four anterior flagella
Axostyle with granules along side
Undulating membrane (along one half of body)
Single nucleus

Question 15

Answer 15

Trichomonas vaginalis trophozoite

Question 16

Trichomonas vaginalis Pathology

Answer 16

Vaginal inflammation with discharge,
asymptomatic in males or a persistant-recurring urethritis may cause neonatal pneumonia and respiratory distress in infants (wet prep of sputum)

Question 17

Trichomonas vaginalis Diagnosis

Answer 17

Wet prep of vaginal and urethral discharges - examine for motility, seen in urine sediment, visualized using fluorescent stains and growth in culture (not common)

Question 18

Trichomonas vaginalis Treatment

Answer 18

Flagyl

Question 19

Trichomonas vaginalis Cyst

Answer 19

No Cyst Stage

Question 20

Diaentamoeba fragilis Diagnosis

Answer 20

Permanent stained smear (Trichrome)

Question 21

Diaentamoeba fragilis Cyst

Answer 21

No Cyst Stage

Question 22

Giardia lamblia Diagnosis

Answer 22

Direct prep
Concentrate and Permanent Stained smears
Duodenal aspirate (examine mucus for motile trophs)
ELISA methods (not fool proof as antigen may be too low)
Fluorescent monoclonal AB
String test or Entero-Test

Question 23

Giardia lamblia Treatment

Answer 23

Metronidazole

Question 24

Trichomonas hominis Diagnosis

Answer 24

Wet prep look for motility especially undulating membrane and presence of axostyle
Stained fecal smears

Question 25

Trichomonas hominis Cyst

Answer 25

No Cyst Stage

Question 26

Chilomastix mesnili trophozoite

Answer 26

6-24 um x 4-8 um Pear shaped Single anterior nucleus Contains curved posterior Distinct cytostomal groove close to the nucleus 4 anterior flagella

Question 27

Answer 27

Chilomastix mesnili trophozoite

Question 28

Chilomastix mesnili cyst

Answer 28

6-10 um x 4-6 um Pear or lemon shaped Single nucleus Single curved cytostomal fibril - "shepherd's crook" Clear knob on cyst

Question 29

Answer 29

Chilomastix mesnili cyst

Question 30

Chilomastix mesnili Pathology

Answer 30

Nonpathogenic, no treatement

Question 31

Chilomastix mesnili Diagnosis

Answer 31

Permanent stained smear (Trichome)

Question 32

Trichomonas tenax trophozoite

Answer 32

Smaller and more slender than T. hominis Four anterior flagella Pyriform shape Single nucleus Axostyle Undulating membrane that extends to 3/4 length of body

Question 33

Answer 33

Trichomonas tenax trophozoite

Question 34

Trichomonas tenax Pathology

Answer 34

Rare reports of respiratory infections and thoracic abscesses Otherwise harmless commensal in mouth

Question 35

Trichomonas tenax Diagnosis

Answer 35

Recover from teeth, gums, or tonsillar crypts

Question 36

Trichomonas tenax cyst

Answer 36

No Cyst Stage

Question 37

Balantidium coli trophozoite

Answer 37

Large, oval shape 50-100 um x 40-70 um (easily seen in wet preps) Cilia aid in locomotion - organism thrives on starch foods Cytostome Two nuclei: micro and macronucleus Vacuoles in cytoplasm

Question 38

Answer 38

Balantidium coli trophozoite

Question 39

Balantidium coli cyst

Answer 39

50-70 um in diameter Spherical or ellipsoid Thick refractile cyst wall Cilia may be present in newly encysted organisms Two nuclei: micro and macronucleus

Question 40

Answer 40

Balantidium coli cyst

Question 41

Balantidium coli Pathology

Answer 41

Asymptomatic carrier state mild colitis and diarrhea acute dysentery

Question 42

Balantidium coli Diagnosis

Answer 42

Wet prep of fresh and concentrated material *does not stain well*

Question 43

Balantidium coli Treatment

Answer 43

Tetracycline

Question 44

Answer 44

Cryptosporidium species acid-fast stain

Question 45

Cystoisospora belli oocyst

Answer 45

22-30 um x 10-19 um Oval tapered at the ends unsporulated when passed in the feces Thin smooth wall and double-layered hyaline wall Contains usually one (rarely two) sporocysts Within 18-36 hrs after feces passed, each of the one-two sporoblasts develops a sporocyst wall and contains four sausage-shaped

Question 46

Answer 46

Cystoisopora belli immature oocyst

Question 47

Answer 47

Cystoisopora belli mature oocyst

Question 48

Cystoisospora belli Pathology

Answer 48

Anorexia nausea Abdominal pain Diarrhea (6-10 per day)

Question 49

Cystoisospora belli Diagnosis

Answer 49

Oocyst seen in wet prep or concentrate acid fast stain

Question 50

Cystoisospora belli Treatment

Answer 50

SXT (Trimethoprim/Sulfamethoxazole) is investigational

Question 51

Answer 51

Cystoisospora belli acid-fast stain

Question 52

Microsporidia species

Answer 52

1-2.5 um Spore is infective stage Polar tubules or filaments unique to this organism Classified as fungi with approximately 14 species that are human pathogens Most commonly seen in AIDs patients and other immunocompromised

Question 53

Answer 53

Microsporidia species acid fast stain