1. Enterobius vermicularis, commonly known as the pinworm, is a parasitic nematode that infects the lower intestine of humans. It is the only parasite that can infect humans. 2. The adult pinworm lives in the cecum and appendix of the intestine. The female migrates to the perianal area at night to lay eggs, causing intense itching. 3. Pinworms are transmitted through the fecal-oral route when eggs are ingested. Diagnosis involves detecting eggs on anal swabs in the morning. Treatment involves a single dose of anthelmintic medication such as pyrantel pamoate or albendazole.

1. NEMATODES

2. s
Sarcomastigophora
Apicomlexa
Microspora
Ciliophora

3. HELMINTH

4. HABITAT CLASSIFICATION

6. ENTEROBIUS VERMICULARIS
• Introduction
• Habitat
• Morphology
• Life Cycle
• Pathogenicity
• Clinical Features
• Laboratory Diagnosis
• Treatment

7. INTRODUCTION
• Previously Oxyuris vermicularis
• Humans – The only hosts
• Pinworm (“Threadworm”)
• Person sleeps, female pinworms leave the
intestine through the anus and deposit their eggs

8. HABITAT
• Caecum
• Appendix
• In submucosa

9. MORPHOLOGY
• ADULT
White, Spindle shaped
Anteriorly - Cervical alae ( wing like expansion)
Posteriorly – Globular bulb ( esophagus)
MALE FEMALE
2-4mm * 0.1-02mm 8-12 * 0.3-0.5mm
Post 1/3 – sharply truncated Posterior – long
tapering tail
Rarely visualised -? After laying eggs
dies 2-3weeks

10. • Floats in saturated salt solution
- Planoconvex!
- Transparent shell

13. LIFE CYCLE
• Newly laid eggs in perianal skin
• Contains larva
• Completes development in 24-36 hours
• Ingestion of these eggs by next human
• Egg shells dissolved by juices, larva goes to small intestine
• Small intestine – Adolescent worm
• Sexually mature – Male fertilizes female and dies
• Gravid female migrate to caecum and appendix
• Lays eggs in perianal skin

15. PATHOGENICITY
• At Risk
– school-aged and preschool-aged children,
– institutionalized persons
– household members and caretakers of persons with
pinworm infection.
• Mode of Infection
Ingestion of eggs with larva ( fecal-oral route )
Autoinfection – laying of eggs - itching – fingers – mouth
Retroinfection – Larva hatched in perianal skin travel
back to rectum

16. CLINICAL FEATURES
• Pruritis periani and perineum
• Salpingitis
• Nocturnal enuresis
• Inflammation of appendix

18. LABORATORY DIAGNOSIS
• Divided into 2 – Detection of Adult worm
Demonstration of Eggs
• Detection of Adult Worms
- Self detection by self / parents
- Passage in stools normally / after enema
- Inspection of anal region

19. DEMONSTRATION OF EGGS
• Direct smear
• Concentration
method
• Sample collection –
NIH swab – early
morning

21. TREATMENT
• Pyrantel Palmoate – 10mg/kg SD
• Albendazole - 400 mg SD
• Mebendazole - 100mg SD

22. TRICHURIS

24. INTRODUCTION
• Linnaeus in 1771, AKA – Whipworm
• Trichuris trichiura
• Trichuriasis
• Large intestine – caecum, appendix
• Tropics

25. MORPHOLOGY
• ADULT
Whip shaped
Male – 30 – 45 micron
Ant 3/5th – Thin, Post 2/5th – Thick coiled
Post end – Males – coiled
Females – comma shaped
Life – 5-10yrs

27. • EGGS
Barrel shaped
Projecting mucus plugs – Each Pole
Bile stained
Plugs – colourless
Float – sat salt
Freshly passed eggs in stool – NOT INFECTIOUS

30. LIFE CYCLE
• Single host , No INTERMEDIATE
• Adult worm live in LARGE intestine
• Eggs passed in soil
• Development - Rhabditiform larva in eggs develops
(Tropical >> Temperate)
• Embryonated eggs – Infective
• Ingested
• Egg shell dissolves
• Larva comes out
• Caecum
• Sexually mature
• Lay eggs

33. PATHOGENESIS
• Whipworm infection
• Asymptomatic
• Massive Infection
– Mechanical obstruction
– Allergic
– Rectum – edematous – difficult to defecate
– Rectal bleeding
– Abdominal cramps

34. LABORATORY DIAGNOSIS
• Stool microscopy
• Eggs +

35. TREATMENT AND PROPHYLAXIS
• Metronidazole
• Proper disposal of feces
• Avoid eating raw vegetables
• Identifying infected patients