Week 5: NEMATODES

• Viviparous- Parasite that lays larva instead of ova/egg.
• Oviviparous- Parasite that lays eggs which hatch before

  leaving the host.
• Oviparous- Parasite that lays eggs which hatch after leaving the host.
• ASCARIS LUMBRICOIDES

  Common name: Large intestinal roundworm, Roundworm of man, Giant intestinal roundworm (it is bigger than any parasite, looks like spaghetti pasta).
• ASCARIS LUMBRICOIDES

  Location: Duodenum and Small Intestine

  Life Span: 12 Months
• ASCARIS LUMBRICOIDES( Unfertilized egg)

  • 85 to 95 micrometers by 38 to 45 micrometers in size

  • Oblong shape

  • Amorphous substances inside
• ASCARIS LUMBRICOIDES( Fertilized egg)

  •Embryonated inside

  • Smaller than unfertilized egg

  • 40 to 75 micrometers by 30 to 50 micrometers • Circle/ round shape.

  • Thick shell/ Thick chitin

  • It can be corticated or decorticated.
• ASCARIS LUMBRICOIDES( Adult: under the microscope)

  The female is larger than the male.
• ASCARIS LUMBRICOIDES( Adult: under the microscope)

  The female gives 240,000 of eggs/ova a day.

  Whether it is fertilized or unfertilized.
• TRICHIURIS TRICHIURIA

  Common Name: Whipworm (because it is long and have whip like structure),
• TRICHIURIS TRICHIURIA

  Location: Large Intestine

  Life Span: 4-6 Years

  Mode of attachment: Sown into the intestine in a pin fashion manner.
• TRICHIURIS TRICHIURIA (fertilized egg)

  It has bipolar mucous plugs/bipolar hyaline plugs (both end sides)

  • “Japanese lantern egg/ova” or “barrel shape eggs/ova” “football shape”
• TRICHIURIS TRICHIURIA (fertilized egg)

  • Double layered or double walled

  • The common size is usually 50-55 micrometer by 25

  micrometer, though it may still vary.
• TRICHIURIS TRICHIURIA

  If it’s a male, it has a mouth in the smaller end.
• TRICHIURIS TRICHIURIA

  Looks like a whip.
• HOOKWORMS

  Common Name: New World Hookworm (Necator americanus), Old World Hookworm (Ancylostoma Duodenale)
• HOOKWORMS

  Location: Small Intestine

  Life Span: 6-8 years, maximun of 15 years
• HOOKWORMS (Fertilized egg)

  • Looks like morula balls.

  • In some, it has 8 morula balls, but it still may vary.

  • Singe walled.

  • They usually stay in the small intestine.
• LEFT SIDE: RHABDITIFORM LARVA

  Can be distinguished by the shorter buccal capsule

  and larger genital primordium.
• RIGHT SIDE: FILARIFORM LARVA

  •The tail is notched and the esophagus is about one- half the length of the body.
• Necator americanus (Left side) we can see the presence of cutting plates in the buccal capsule; they don’t have teeths it just looks like a fold.
• Ancylostoma Duodenale (Right side) we can see the presence of the dental pattern/teeth in the buccal capsule.
• STRONGYLOIDES STERCORALIS

  Common Name: Threadworm, traveller’s diarrhea
• STRONGYLOIDES STERCORALIS

  • The only Parthogenic Nematode
• (strongyloides stercoralis egg)

  Habitat : Usually stays in small intestine, duodenum, upper jejunum

  Mode of attachment: It buries itself in the mucosal epithelium of your intestine.
• (strongyloides stercoralis egg)

  Histologic techniques in the intestine looks like honeycomb intestine

  Average size: between 48 by 35 micrometer

  • Shell: has a thin hyaline shell
• Rhabiditiform larva

  •Average size : 220 by 15 micrometer

  •Has a short buccal capsule / cannal compared to

  filariform larvae
• Flariform Larva

  •Considered long and slender

  •Average length : 690 micrometer

  •Has a long esophagus

  •Non feeding stage of S. Stercoralis
• ENTEROBIUS VERMICULARIS

  Common name : Pinworm, Seat worm, (old name) Oxyuris Vermicularis, Society worm, Social worm
• ENTEROBIUS VERMICULARIS

  Habitat : In the middle of duodenum and colon, cecum of the intestine
• ENTEROBIUS VERMICULARIS

  • Lifespan of E. Vermicularis :

  Female–lives up to 4 to 6 days Male – After coppulation (sexual intercourse with female E. Vermicularis) it dies
• Female E. Vermicularis – has a fatal embrace *only the female E. Vermicularis hatches its eggs in the perianal every dawn or when the patient has enough long sleep*
• Familial Disease – if one member of the family is infected, most likely the whole family can also be infected.
• (Enterobius Vermicularis egg)

  • D-shaped, Baguette cut, tadpole like ova, Itallian bread ova

  • Oval but flattened on one side, hence giving the illusion of letter D
• (Enterobius Vermicularis egg)

  • Size

  Length - 48 to 60 micrometer long

  Width - 20 to 35 micrometer wide
• (Enterobius Vermicularis egg)

  Outermost part of the egg - has thick albumin layer

  Inner layer – lipid layer
• Enterobius Vermicularis (Female and Male Adult)

  • Female E. Vermicularis is always larger than the male Vermicularis.

  • Retro Infection - In some, they also harbor eggs inside the patient.
• CAPILLARIA PHILIPPINENSIS

  Common name : Pudoc worm, Mystery worm
• CAPILLARIA PHILIPPINENSIS

  • It is called the mystery worm because it is the

  smallest human nematode
• CAPILLARIA PHILIPPINENSIS

  • First discovered in the Philippines. First found in ilocos Norte.