1. Luminal & intestinal flagellates
Giardia lamblia (flagellate) Disease : Giardiasis (lambliasis).
Epidemiology: It has worldwide distribution.
It is the most common protozoan intestinal disease in disease.
This parasite more prevalence in children under 10 years old.
Habitat→→ duodenum and upper jejunum.
Infective stage → → Mature quadrinucleate cyst.
Pathogenic stage → →Active trophozoite.
Diagnostic stage → → Mature cyst and trophozoite in stool sample.
Mode of infection → → Contamination of food and water with cyst.
Route of entry → → is mouth or orally.

2. Morphology: Cyst: Trophozoite: Morphology:
There are two stages:
Trophozoite: Morphology:
→→ It is µ pear shaped with 8 flagella(f) and, axostyles(a) arranged in a bilateral symmetry.
→→ There are two anteriorly located large sucking discs(d).
→→ The cytoplasm contains two 2 nuclei (n) with karyosome (k) and 2 Para basal bodies(p.b).
Cyst:
→→ Giardia cysts are 9-12 microns.
→→ Ovoid in shape with well-defined cyst wall(c.w).
→→ The cytoplasm contains 4 nuclei(n) .
→→ many structures of the trophozoite like axostyles (a) and parabasal bodies(p.b).
Morphology:

3. Life cycle of G. Lamblia
→→ Life cycle: Infection occurs by ingestion of cysts, usually in contaminated water. →→ Ex-cystation occurs in duodenum and trophozoites colonize the duodenum where they may swim freely or attach to the sub-mucosal epithelium via the ventral suction disc. →→ The free trophozoites encysted in the colon. →→ The cysts are passed in the stool. →→ Man is the primary host and some animals(e.g. pigs and monkeys, mice…..etc) are also infected and serve as reservoirs. →→ Afterrward, person-to-person transmission is possible.

4. Life cycle of Giardia lambelia

5. Symptoms & Pathology:
Symptoms: The early symptoms include →→ abdominal pain and distension, nausea and fatty diarrhea (steatorrhea). →→ The stool contains excessive lipids but very rarely any blood or necrotic tissue. The more chronic stage is associated with vitamins A and B12 Malabsorption, disaccharides deficiency. : Pathology →→ Covering of the epithelium by the trophozoite causing malabsorption of nutrients.

6. Diagnosis Diagnosis: by Symptoms, history, epidemiology.
→→ Distinct from other dysentery due to lack of mucus, and blood in the stool, lack of increased PMN leukocytes in the stool and lipids droplets & lack of high fever.
→→ Cysts in the stool and trophs in duodenal content obtained using a string device (Enterotest R).
→→ Trophozoite must be distinguished from the nonpathogenic flagellate Trichomona hominis, an asymmetrical flagellate with an undulating membrane.

7. GIARDIA Treatment Treatment:
Keep the child hydrated. If it is dehydrated:
Using drugs
1-Metronidazole(Flagyle).
2-Tinidazole a new Giardia alternative drugs
(but it has a shorter treatment course) used for under 3 years children.

8. LUMINAL flagellates
→→ Lumen-dwelling F: Flagellates found in the lumen of alimentary canal and UGT.
Genus :Trichomonas.
General characters.
→→ The genus Trichomonas consists of 3 main species which infect man.
→→ All 3 spps. have direct life cycle .
→→ All Trichomonas posses 3 to 5 anterior flagella, an undulating membrane, and a recurrent flagellum attached to the edge of the undulating membrane.
→→ An axostyle extended along the length of the body and extends from posterior.
→→ reproduce by longitudinal binary division .
→→ A cyst stage is not known for this genus.

9. Trichomonas
There are three species of genus Trichomonas 1-Trichomonas tenax →→Living in the mouth and teeth pockets. →→ Moving vigorously by flagellum through saliva, feeding on food debris. →→ The tissue destruction has been done by toxins produced by this and other pathogens at the site of infection. 2-Trichomonas hominis. →→ Lives in the intestine. →→ It is cosmopolitan in distribution. →→ It is thought to be non-pathogenic although it has been associated with diarrheic stools.

10. 3-Trichomonas vaginalis
$ $→ → Trichomoniasis disease. $ $→ → It is sexually transmitted disease. Epidemiology: It has a world-wide. Morphology: Trophozoite: half pear shaped with a single nucleus and 4 anterior flagella and a lateral flagellum attached by an undulating membrane, 2 axostyles arranged asymmetrically. The organism does not encysted

11. Life cycle

12. Trichomonas vaginalis
Pathogenesis: →→ Trophozoite infect the squamous epith. Cells. →→ It is asymptomatic particularly in male. →→ In females causing severe causing irritation& Inflammation of the vaginal mucosa(vaginitis) or inflammation uterine cervix(cervicitis). →→ In males causing inflammation of urethra and prostate (urithritis and prostatitis). Clinical symptoms : →→ majority of infected males without symptoms and ⅓ of infected females without symptoms. →→ both in male and female genital discharge and pain in urination.

13. Diagnosis and treatment
→→ By GUE or males and females UG swab and smear stain with Giemsa stain.
Treatment.
1-Metronidazole(Flagyle) tablets for men and vaginal suppositories for females.
2-Tinidazole alternative drug. it has a shorter treatment course.