Medical parasitology

1. Trichuris trichiuria
 causes trichocephaliasis
(whipworm infection).
 Distribution: worldwide,
especially in the tropics.
 Morphology: Adult female
worms are up to 5,5 cm in
length, and male are up to 4
cm. The anterior end of the
body is hairlike.
 The eggs are brown, barrel-
shaped with a plug at each
end, 20-50 micro.m in size.

2. Trichuris trichiura:
A-Female:
whip-like body
with thin anterior
2/3body
thick posterior 1/3 body.
bead-like cells
surrounding intestinal
tract in the anterior end,
called stichocytes.

3. B-Male:
body same as in female.
posterior end strongly curved with
one spicule.

5. Egg:
Size: 50-54m
Shape: "tea tray eggs” or
barrel- shaped with a
colorless protruding mucoid
plug at each end
Shell: fairly thick and smooth,
with two layers & bile stained
Color: yellow brown
Content: a central granular
mass which is Unsegmented
ovum

6. Trichuris trichiura Egg 50 X 25 µm
Note : the egg barrel – shaped, with two polar plugs yellowish brown in colour
( bile – stained ) has a double shell, the outer one is bile – stained
In Iodine s.
In saline s.
Plug
Plug

7. Trichuris trichiura
Life cycle

8. 
Pathogenesis and clinical manifestation:
Adult worms burrow their hairlike anterior ends into the intestinal
mucosa. They feed blood. Trichuris may cause diarrhea, abdominal
pain, nausea, acute appendicitis. Most infections are asymptomatic.
Clinical Features
 Are largely determined by the worm burden:
 < 10 worms are asymptomatic (99% asymptomatic)
 Heavy worm burden
 Mechanical damage to the intestinal mucosa
 Chronic profuse mucus and bloody diarrhea with
abdominal pains and edematous prolapsed rectum

9. Anaemia from blood loss and iron deficiency,
malnutrition, weight loss and sometimes
death
Each adult worm sucks about 0.005
ml of blood per day
Rarely a child will develop congestive cardiac
failure because of anaemia and fluid retension
hypoproteinemia and oedema

10. Trichuris trichiura in the large intestine. Many worms are present, each
with its anterior end embedded in the intestinal mucosa, resulting in
the erythema.
symptum, with havey infection ( prolapse of the rectum )

11. Laboratory diagnosis:
microscopic examination of feces (finding the
typical eggs).
Prophylaxis:
 washing hands before meals;
 proper washing of vegetables eaten raw;
 treatment of patients;
 proper disposal of feces; health education.