1. Hymenolepis nana
Huda Alislam
Huda Alislam

2. Hymenolepis nana

3. Introduction
• The dwarf tapeworm is a species of tapeworm that
is classified in the Platyhelminthes phylum.
• It once held two other scientific names including(
Vampirolepis nana) and (Taenia nana)

4. Introduction
• H. nana was first identified as a human parasite by
Von Siebold in 1852.
• H. nana is the most common cestode in humans
with infection prevalence highest among children
and in warm arid climates with poor sanitation
facilities

5. Morphology of parasite
• Its small measuring only
10-44mm in length
• It consists of 100-200 short wide
segments
• Long neck and scolex which has
suckers and hooks

7. Morphology of eggs
• It is colourless ,ovale or round
• Measuring 30-45 m in
diameter.
• Hooklets are present in embryo.
• At each end of the egg thread-
like structures called polar
filaments are usually visible.

9. Transmission
• Ingesting eggs in food or drink or from
contaminated hands .
• Internal autoinfection

12. H.nana development in GI tract

13. Clinical features
• Symptoms are very rarely serious except in children
may cause abdominal pain and diarrhoea
• Patients with more than 15,000 eggs per gram of
stool may experience cramps, diarrhea, irritability,
anorexia.

14. Clinical features
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enteritis caused by cystercoids
Itchy anus
Poor appetite
Weakness
Allergic reactions due to toxins released from the
worms

15. Clinical features
• Severe and sometimes disseminated infections can
occur in malnourished or immunsuppressed
persons

16. Laboratory diagnosis
• Finding the eggs of the parasite in feaces by
• Direct examination
• Concentration techniques and examination of
several specimens may be required .

17. Treatment
• Praziquantel
• Nitazoxanide
• Niclosamide

18. prevention &control
• Practicing personal hygiene especially the washing
of hands before eating
• Providing latrines and encouraging their use
especially by children
• Avoiding eating uncooked food which may be
contaminated with human feaces