This document provides an overview of intestinal parasites, including their classification, epidemiology, risk factors, clinical presentation, diagnosis, treatment and prevention. It discusses the major intestinal parasite groups - protozoa like Entamoeba histolytica and Giardia lamblia, helminths like Ascaris lumbricoides and hookworms, and their life cycles, symptoms and global prevalence. Physical examination findings, laboratory investigations, imaging and specific antiprotozoal or anthelmintic treatments are outlined. The conclusion emphasizes the importance of both therapeutic and preventive approaches to control intestinal parasitic infections.

1. Epid
Classification
Preventio
n
Conclusi
on
DEPARTMENT OF PAEDIATRICS
FACULTY OF CLINICAL SCIENCES
COLLEGE OF HEALTH SCIENCES
UNIVERSITY OF ABUJA
A SEMINAR PRESENTATION ON
INTESTINAL PARASITES
Amaye-Igonikon, Babema Tonye
16/11/21

2. Parasites are organisms that
depend on other organisms for
food causing them harm in the
process.
Three main classes cause
human diseases: protozoa,
helminthes, and ectoparasites.
Intestinal parasites are a
group of worms that affect the
gastrointestinal tract
primarily.
Introductio

3. Epid.
Intestinal Parasitic
Infections (IPI’s)
01
Still a major global health
concern, especially in
developing nations.
02 ~ 3.5 billion people are
affected globally
Nigeria: Almajiris, 80.9%,
South-West, 28%; South-East,
55.2%; South-South, 67.2%
04
95% of school children in
Ethiopia; 90% in Central
Sudan, 84.7% in Burkina Faso
03

4. Risk Factors

5. Classification
Figure 1: Classification of Intestinal Parasites (Bioscience, n.d.).

6. Amoebae: Entamoeba histolytica (1/2)
 Losch, 1875.
 Three forms – trophozoites,
pre-cyst, and the cyst.
 Intestinal & extra-intestinal
amoebiasis.
Fig. 2: Trophozoite
Fig. 3: Pre-cystic Stage Fig. 4: Mature Cyst

7. Amaoebae: Entamoeba histolytica (2/2)
Fig. 5: Life Cycle of E. histolytica (Tankeshwar, 2021)
Fig. 6: Flask-Shaped Ulcer – E.
coli
Fig. 7: Amoebic Liver Abscess – E. coli

8. Flagellates: Giardia lamblia (1/3)
 Unicellular, eukaryotic; a.k.a.
G. intestinalis, G. duodinalis
 Diarrhoeal diseases globally.
 Trophozoite and cystic stages.
Fig 8: G. lamblia – Trophozoite (Standford, n.d.). Fig 9: G. lamblia – Mature Cyst

9. Flagellates: Giardia lamblia (2/3)
Fig. 10: Life Cycle of G. lamblia (Esch
and Petersen, 2013)
Fig. 11: Giardiasis (SEM)

10. Flagellates: Giardia lamblia (3/3)
Fig. 12: G. lamblia – Reservoir Hosts

11. Coccidia: Cryptosporidium spp.
 A cause of diarrheoal diseases.
 Cryptosporidiosis, RVD patients
at risk (White and Seenevasan,
n.d.).
 8 named (MMy Fine SCAPH) & 6
unnamed spp. cause infections
in immunocompetent and
immunoincompetent humans
(Molloy et al., 2010).
Figure 13: Cryptosporidium Subtypes
(Lebbad et al., 2021)

12. Coccidia: Cryptosporidium parvum.
Fig. 14: C. parvum in a stool smear
micrograph
Fig. 15: Life Cycle of C. parvum

13. Helminths: Nemathelminths - Ascaris lumbricoides (1/3)
 Round worm.
 Very common
(Asaolu, Ofoezi, and
Onyeju, n.d.).
 Endemic in tropical
and temperate
regions.
 Moisture; LSES.
 Jejunum.
Fig. 16: A. lumbricoides,
M & F (Akpeli, 2019)

14. Helminths: Nemathelminths - Ascaris lumbricoides (2/3)
Fig. 17: A. lumbricoides – Life Cycle (CDC, 2019) Fig. 18: A. lumbricoides - Eggs

15. Helminths: Nemathelminths - Ascaris lumbricoides (3/3)
Fig. 19: A. lumbricoides - Anatomy Fig. 19: A. lumbricoides – Intestinal Obstruction
(Mbanga, Ombaku, and Agbor, 2019)

16. Helminths: Nemathelminths – Enterobius vermicularis (1/2)
 Pin worm (Babady et al.,
2011).
 Children commonly
infected worldwide.
 Faeco-oral; fomites.
 Pruritus ani,
appendicitis, intestinal
abscess.
 Extraintestinal
presentation, rare – FGT. Fig. 21: E. vermicularis –
Adult Worm (CDC, 2019)
Fig. 20: E. vermicularis
– Eggs

17. Helminths: Nemathelminths – Enterobius vermicularis (2/2)
Fig. 22: E. vermicularis – Life Cycle

18. Helminths: Nemathelminths – Hookworms (1/3)
 Tropical and
subtropical nations.
 Name: from bent
anterior end of adult
worm.
 Ancyclostoma
duodenale and Necator
americanus.
 Iron deficiency
anaemia – worse in
pregnant women and
children.
Fig. 23: Hookworm - Eggs Fig. 24: Adult Hookworm

19. Helminths: Nemathelminths – Hookworms (2/3)
Fig. 25: Hookworm – Life Cycle Fig. 26: Foot Showing Hookworm

20. Helminths: Nemathelminths – Hookworms (3/3)
Table 1: Clinical Features of Hookworm Disease (Blair, 2015)

21. Helminths: Nemathelminths – Others
 Strongyloides
stercoralis – thread
worm.
 Autoinfective
 Transdermal
infection,
contaminated soil.
 68.5% fatality rate if
disseminated (Page,
Judd, and Bradbury,
2018).
 Strongyloidiasis;
asymptomatic in
50% of cases
 Trichuris trichiura –
whip worm.
 Soil-transmitted.
 Trichuris Dysentric
Syndrome (TDS) in
young children
especially (Bianucci
et al., 2015).
 Heavy infection –
ileitis.
Fig 27: S. stercoralis –
eggs and adult worm
Fig 28: T. trichiura egg

22. Trematodes – Fasciolopsis buski
 Largest intestinal fluke
affecting humans.
 Humans’ and pigs’
intestines.
 Enteritis, malnutrition.
Fig. 29: F. buski – Life Cycle

23. Cestodes: Taenia spp. (1/2)
 T. saginata – beef
tape worm.
 Intermediate host
- cattle.
 Humans –
definitive host;
S.I.
 Taeniasis
 Eggs – diagnostic
stage.
 T. solium – pork
tape worm.
 Intermediate
host - swine.
 Humans –
definitive host;
S.I.
 Taeniasis,
cysticercosis.
 Eggs – diagnostic
stage.
Fig. 30: Taenia spp.

24. Cestodes: Taenia spp. (2/2)
Fig. 31: Taenia spp – Life Cycle

25. Cestodes: Others
 H. nana – dwarf
tapeworm.
 Faeco-oral
 Internal
autoinfection
 Abdominal pain
and diarrhoea in
children.
 D. latum – broad
fish tapeworm.
 Raw or poorly-
cooked fish.
 Internal
autoinfection
 Adult worm – S.I.
 Broadly
asymptomatic;
mild enteritis.
Fig. 32: H. nana - Colonoscopy
Fig. 33: D. latum

26. Management (1/4)
History (Elmonir et al., 2021)
Asymptomatic (26.8%)
Nonspecific:
nausea, vomiting,
dizziness,
abdominal cramps
diarrhoea, bloody
diarrhoea, appetite
loss, UWL, fever,
etc.
Specific:
Itchy anus,
Generalized body
itching
Respiratory symptoms

27. Management (2/4)
GPE
Nil findings.
Inspection
Restless/irritable, small for
age, malnourished,
unkempt, scratch marks,
erythematous papules, etc.
Palpation
Dehydrated, febrile, pale,
icteric, lymphadenopathy,
finger clubbing, etc.
ABDOMINAL EXAMINATION
Nil findings.
Inspection
Distended abdomen.
Palpation
Abdominal tenderness,
hepatomegaly, rectal prolapse,
etc.
Auscultation
Normo/Hyper/Hypoactive
bowels.
Physical findings from other
systems possible.

28. Management (3/4)
Investigations (CDC, 2021)
Stool analysis (ova and
parasite test)
Blood tests (serology and
smear)
Endoscopy/colonoscopy
Jejunal biopsy
Imaging
- X-ray
- Abdominal USS
- MRI
- CAT scan
Fig. 34: Abdominal USS Showing
Tramway Sign – A. lumbricoides

29. Management (4/4)
Specific Treatments
E. histolytica – tinidazole
G. Lamblia – metronidazole
C. Parvum – nitazoxanide
E. Vermicularis –
metronidazole, pyrantel
pamoate, albendazole.
Ascariasis – piparazine or
thiabendazole
Specific Treatments
Hookworm – mebendazole,
thiabendazole (post-Rx iron
for 2-3 months).
F. Buski – praziquantel.
Taenia spp. – niclosamide.
Complications
Treat dehydration,
malnutrition, anaemia,
heart failure, etc, if present.

30. Prevention
General Protection
- Health education
- Environmental, food,
and personal hygiene
- Welfare programs
Specific Protection
- Preventive
chemotherapy (WHO,
2017)
Early Diagnosis and
Treatment
- Prompt hospital
presentation
- HIS
- Prompt diagnosis
and adequate Rx.
Limitation of Disability
- Adequate fluid
support
- Haematinics or blood
transfusion, if
indicated
- Antipyretics
- Nutritional support
- Respiratory support,
if indicated
Rehabilitation
- Housing support
- Parents’/guardians’
career support

31. Conclusion
Undoubtedly, the advent of
therapeutic chemotherapy
for intestinal parasitic
infections has brought about
significant improvement of
prognosis.
This notwithstanding,
maintaining and
improving preventive
measures are sacrosanct
and should therefore be
encouraged.
Merci beaucoup pour
m'écoute!

32. References (1/4)
Abah, A. E., & Arene, F. O. I. (2015). Status of Intestinal Parasitic Infections among Primary School
Children in Rivers State, Nigeria. Journal of Parasitology Research, 2015, 1–7.
https://doi.org/10.1155/2015/937096
Akpeli, A. O. (2019, March 5). Prevalence of ascaris lumbricoides among children. Dutable. Retrieved
November 13, 2021, from https://dutable.com/2019/03/05/prevalence-of-ascaris-lumbricoides-
among-children/
Bianucci, R., Torres, E. J. L., Santiago, J. M. D., Ferreira, L. F., Nerlich, A. G., Souza, S. M. M. D., Giuffra, V.,
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33. References (2/4)
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34. References (3/4)
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35. References (4/4)
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