Module 6 - Other Protozoans

Ciliophora

Classification of Balantidium coli

Balantidium coli

LARGEST protozoan and ONLY ciliate known to affect humans

Balantidium coli

Has the ability to attack large intestine causing dysentery

Dysentery

Diarrhea with blood and mucus

Balantidium coli

It causes Balantidiasis/ Balantidiosis/ Balantidial dysentery

Pigs and swines

Primary reservoir of Balantidium coli

• Asexual: Assymetric Binary Fission

• Sexual: Conjugation

Reproduction of Balantidium coli

• 30-150 um long

• 20-120 um wide

Size of trophozoite stage of Balantidium coli

• 40-60 um in diameter

Size of cyst stage of Balantidium coli

Rotary, boring

Motility of Balantidium coli, trophozoite

Non-motile

Motility of Balantidium coli, cyst

• Cilia

• Cytostome

• Cytopyge

Parts of trophozoite stage in Balantidium coli

Locomotion

Cilia

Oral apparatus

Cytostome

Waste excretion

Cytopyge

• Macronucleus (vegetative and asexual reproduction)

• Micronucleus (sexual reproduction)

2 types of nucleus in Balantidium coli, trophozoite and cyst

• Spherical to ovoid

• Retracted cilia

• Double cyst wall

Description of cyst stage in Balantidium coli

• Young cyst (cilia found between cells)

• Mature cyst (NO cilia)

Parts of cyst stage in Balantidium coli

• Macronuclues (kidney/bean)

• Micronucleus (round)

Shape of Macro and Micronucleus

Two contractile vacuole

How many vacuoles in Balantidium coli, trophozoite

Osmoregulatory organelles

Two contractile vacuole:

1 or more contractile vacuoles

How many vacuoles in Balantidium coli, cyst

Ingestion of food and/or water with contaminated Balantidium coli cyst

Mode of Transmission in Balantidium coli

Cyst

Infective stage of Balantidium coli

4-5 days

Incubation period of Balantidium coli

Several weeks

Cyst Viability of Balantidium coli

Balantidiasis

Alternative name of Balantidial dysentery

Hyaluronidase

Lytic enzyme of Balantidiasis

Hyaluronidase

Produce by the trophozoite

Rounded base with wide neck

Shape of ulcer in Balantidiasis

• Direct Examination

• Concentration techniques

• Sigmoidoscopy

Lab Diagnosis in Balantidium coli

Hyaluronidase

Repeated stool examination to increase sensitivity

Sigmoidoscopy

Insertion of endoscope in anus and sigmoid colon

• Tetracycline

• Metronidazole

Treatment of choice in Balantidium coli

Yeast

Blastocystis hominis was formerly classified as

Lower Intestinal Tract

Blastocystis hominis is the inhabitant of:

• Asexual: Binary Fission/Sporulation

• Under strict anaerobic condition

Reproduction of Blastocystis hominis

• Ingestion of cyst from contaminated food or water

• Fecal-Oral route

Mode of Transmission in Blastocystis hominis

• Vacuolated

• Multiple Fission

• Granular Form

• Ameba-like Forms

• Avacuolar

• Cyst

Morphological Forms in Blastocystis hominis:

Vacuolated

MOST PREDOMINANT FORM; main culprit for causing diarrhea

Vacuolated

• Spherical

• Large central vacuole: reproductive organelle pushes the cytoplasm and nuclei

Multiple Fission

Arise from vacuolated forms

Granular Forms

Observed from old cultures

Ameba-like Forms

• Occassionaly observed in stool samples

• Active extension and retraction of pseudopodia

• Thick-walled

• Thin-walled

Types of cyst in Blastocystis hominis

Thick-walled cyst

Responsible for external transmission

Thin-walled cyst

Responsible for reinfection within host intestinal tract

19 days in water at room temp.

Blastocystis hominis caspn survive up to

Chlorine

Blastocystis hominis shown resistance in

• White Blood Cells

• Yeast cells

Artifacts confused with Blastocystis hominis

Blastocystosis

Produces a wide variety of intestinal disorders

• Abdominal cramping

• Irritable Bowel Syndrome (IBS)

• Bloating

• Flatulence

• Mild to moderate diarrhea without fecal leukocytes or blood

Blastocystosis produces a wide variety of intestinal disorders such as:

5 or more per 400x field

Presence of Blastocystosis should be reported when they are numerous

• Direct Examination

• Concentration Techniques

• Permanent Slide

• Culture

Lab diagnosis in Blastocystis hominis

Lugol’s Iodine

May be used for initial screening

• Hematoxyline Stain and Trichrome Stain

Stains used for Permanent Slide

• Boek and Drbohlav’s Medium

• Nelson and Jones Medium

Medium used in culture:

• Metronidazole

• Iodoquinol

• Trimethoprim-sulfamethoxazole

Treatment of Choice in Blastocystis hominis:

Oral Apparatus

Tapered anterior end

Waste Excretion

Rounded Posterior End

Mucocyst

• Virulence of organism

• Adhesion

• White Blood Cells

• Yeast cells

Artifacts confused with Blastocystis hominis: