Intestinal Nematodes Flashcards
What do you call the tough protective covering of nematodes that is made up of chitin?
cuticle
Nematodes, when cut in half, are ____.
bilaterally symmetrical
add also:
- nonsegmented
- generally cylindrical
- tapered at both ends
Based on the presence of chemoreceptors, what are the two classes of nematodes?
- Phasmids
- Aphasmids
both are Classes (Class Phasmidia)
The adult female worms are generally ____ then males.
larger or smaller
larger
Nematodes belong to phylum called what?
Nemathelminthes
What do you call the anterior or cephalic sensory organs that some nematodes possess?
Amphids
The general distinction between phasmids and aphasmids is the presence or lack of ____.
what structure?
caudal chemoreceptors
- may caudal chemoreceptors = phasmids
- wala = aphasmids
Which nematodes are aphasmids?
- Trichinella
- Trichuris
- Capillaria
- may caudal chemoreceptors = phasmids
- wala = aphasmids
If the esophagus is uniform throughout, the type is called ____. If the esophagus expands posteriorly into a bulb with a valve mechanism, it is referred to as ____.
filariform; rhabditiform
What do you call the larva that hatches from the egg?
L1
rhabditiform larva
Larva undergoes several molts until it reaches the third stage larva called ____.
L3
Filariform larva
Pls enumerate the Intestinal Nematodes
- Capillaria philippinensis
- Enterobius vermicularis
- Trichuris trichiura
- Ascaris lumbricoides
- Necator americanus
- Ancylostoma duodenale
- Strongyloides stercoralis
CETANAS
Trichinella spiralis is tissue-dwelling na
Which among the nematodes have their adult forms reside in the small intestine?
- Capillaria philippinensis
- Ascaris lumbricoides
- Strongyloides stercoralis
- Hookworm
- Trichinella spiralis
CASHT
Which among the intestinal nematodes have their adult forms reside in the large intestine?
- Enterobius vermicularis
- Trichuris trichiura
Which among the nematodes are extraintestinal?
- Trichinella spiralis
- Microfilariae
- Dracunculus medinensis
- Angiostrongylus cantonensis
TMDA
marami im so sorry can’t include all
Which among the nematodes have heart-lung migration?
- Ascaris lumbricoides
- Strongyloides stercoralis
- Hookworm
ASH
Common name of Ascaris lumbricoides
Giant intestinal roundworm
Habitat of Ascaris lumbricoides
Small intestine
Final host of Ascaris lumbricoides
Man
Infective stage of Ascaris lumbricoides
embryonated egg
What is the most common intestinal nematode?
Ascaris lumbricoides
This is also considered as the largest intestinal roundworm
Ascaris lumbricoides
Ascaris lumbricoides eggs embryonate outside the host within how many weeks?
2-3 weeks
If only the longer and narrower eggs of Ascaris lumbricoides are found, this suggests only ____ infection of Ascaris
male or female
female
3 layers of Ascaris lumbricoides egg
- Outer mammillated, albuminous layer
- Glycogen layer
- Lipoidal vitelline layer
The presence of albuminous and mammillated layer of Ascaris lumbricoides eggs indicate that it is?
corticated
The absence of the lipoidal, vitelline layer of Ascaris lumbricoides eggs means to say that the egg is?
unfertilized
Diagnostic stage of Ascaris lumbricoides
Ova in stool; Adult worm too
MOT of Ascaris lumbricoides
Ingestion of embryonated egg
What do you call the pneumonitis during larval migration of Ascaris lumbricoides?
Loeffler syndrome
besides loeffler syndrome, what are the other two complications caused by Ascaris lumbricoides larva?
- Visceral larva migrans
- Irritation of intestinal mucosa
what are the pathologic complications caused by Ascaris lumbricoides adults?
- Bolus
- Erratism
- Epigastric pain
- Diarrhea (bowel obstruction w/ fever and malaise)
- Malnutrition
- Lactose maldigestion or intolerance
- Ectopic migration to other organs
Ascaris lumbricoides diagnostic tests
- DFS
- Kato-Katz
- FECT
- ZnSO4 flotation
- Radiography
Ascaris lumbricoides drug of choice
- Albendazole
- Mebendazole
- Pyrantel Pamoate
life cycle of Ascaris lumbricoides
kahit own words lang (pls press 5 na agad hehe)
- ingestion of embryonated eggs
- larva sa small intestine
- larva travel to heart via liver hepatic portal veins then hepatic veins then IVC
- larva will reach alveoli then person will cough and ingest larva again then larva will mature sa small intestine
- after maturation, ova sa stool then embryonate sa environment (soil)
Are Ascaris lumbricoides eggs able to survive in 10% formalin solution?
Yes
Common name of Trichuris trichiura
Whip worm
other name is Trichocephalus trichiura
Habitat of Trichuris trichiura
Large intestine
Final host of Trichuris trichiura
Man
Infective stage of Trichuris trichiura
embryonated egg
Diagnostic stage of Trichuris trichiura
Ova in stool
MOT of Trichuris trichiura
ingestion of embryonated egg
Trichuris trichiura eggs close resemble what spp.?
Capillaria philippinensis egg (ova)
Diagnosis of Trichuris trichiura
- DFS
- Kato-Katz
- ZnSO4 flotation
Drug of choice for Trichuris trichiura
trichuriasis
Albendazole & Mebendazole
the ova of Trichuris trichiura has what you call what in its edges?
hyaline plugs
bipolar plugs; mucous plugs
the ova of Trichuris trichiura has what appearance
football-shaped
Japanese lantern appearance; lemon-shaped
One pathologic complication associated with trichuriasis is the loss of too much blood wherein it resulted to the lower-than-normal albumin levels. What is this condition called?
Hypoalbuminemia
C-reactive proteins up; Albumin levels down (in serum electrophoresis)
life cycle of Trichuris trichiura
own words (pls press 5 na agad hehe)
- ingestion of embryonated eggs
- hatching of eggs in duodenum
- larva will go sa cecum where they mature
- after maturation, feces sa stool w/ eggs then embryonate sa environment (soil)
no heart-lung migration
Diseases associated with Trichuris trichiura
- Iron Deficiency Anemia
- Trichuris dysentery syndrome
- Hypoalbuminemia
What do you call the pathologic condition associated with Trichuris trichiura wherein parasite goes to the rectosigmoid area to cause inflammation ?
lower portion of colon becomes turned and protrudes outside (rectum loses its internal support)
Rectal prolapse
Common name for Enterobius vermicularis
- Pin worm
- Society worm
- Seat worm
- Tiwa
other name: Oxyuris vermicularis
Habitat of Enterobius vermicularis
Large Intestine
What do you call the lateral cuticular expansions or lateral wings present in Enterobius vermicularis adults?
cephalic alae
walang sinabing gender kay markell
Final host of Enterobius vermicularis
Man
Infective stage of Enterobius vermicularis
embryonated egg
Enterobius vermicularis diagnostic stage
Ova & Adult worm
MOT of Enterobius vermicularis
- Ingestion of embryonated egg
- Inhalation of embryonated eggs
- retroinfection (sa loob lng bbalik ulet)
- autoinfection
Diagnostic tests for Enterobius vermicularis
- perianal swab
- swellengrebel
- Flotation techniques
What do you call the type of autoinfection in Enterobius vermicularis involving migration of hatched embryonated eggs in the perianal area back into the rectum and large intestine?
Retroinfection
Enterobius vermicularis drug of choice
- Albendazole
- Mebendazole
- Pyrantel pamoate
major characteristics of Enterobius vermicularis ova
kahit 2 lng
- Thick, translucent shell
- D-shaped; lopsided
Two layer of Enterobius vermicularis ova
- Albuminous coat/layer
- Lipoidal layer
Why are eggs of E. vermicularis seldomly found in stool (5% recovery)?
females do not oviposit until they leave the intestinal tract
How many consecutive instances of perianal swab should be taken before a px is declared Enterobius vermicularis-free?
5-7
What do you call the itching associated with Enterobius vermicularis?
pruritus ani
The ova of Enterobius vermicularis has been associated with the existence of what flagellate?
Dientamoeba fragilis
Pathology of Enterobius vermicularis
- Pruritus ani
- Weight loss
- Irritation
- Vaginitis
- Bacterial infection
how many hours will it take for Enterobius vermicularis ova to embryonate?
4-6 hours
life cycle of Enterobius vermicularis
(pls press 5 na agad hehe)
- ingestion of embryonated eggs
- hatch in small intestine then larva travels to large after maturation
- gravid female comes out during night and oviposits then dies (usually)
- some eggs attach s linen and some stay sa anus
- 4-6 hrs b4 embryonation and no need ng soil or smth
- then retroinfection or autoinfection or infect ng iba
Common name of Capillaria philippinensis
Pudoc worm
first recovered by Nelia Salazar
Habitat of Capillaria philippinensis
Small intestine
Final host of Capillaria philippinensis
Man
pwede ring migratory birds
- incidental nga raw tayo sabi ni markell (final/incidental)
Brackish and freshwater fishes such as Bagsang, Bagsit. Birot, and Ipon are what type of hosts in the life cycle of Capillaria philippinensis?
Intermediate hosts
Infective stage of Capillaria philippinensis
larva in infected fish
Capillaria philippinensis diagnostic stage
Ova in stool
(typical ova)
MOT of Capillaria philippinensis
ingestion of raw or undercooked fish containing the larva
2 types of Capillaria philippinensis adult female?
- Typical female
- Atypical female
What type of Capillaria philippinensis female lays oviparous eggs which appear as peanuts?
Typical female
oviparous eggs pass in stool
What type of Capillaria philippinensis female lays ovoviviparous eggs which appear as multisegmented or embryonated?
also responsible for autoinfection
Atypical
Sometimes, first gen female is larviparous too and that counts sa atypical type
Diagnostic tests for Capillaria philippinensis
- DFS
- FECT
- Kato-Katz
- Duodenal aspirate
Pathology of Capillaria philippinensis includes:
- Intestinal capilliariasis
- Mystery disease
- Severe watery diarrhea
- Borborygmus
- Malabsorption that results in electrolyte imbalance
- Alteration of intestinal villi
Drug of choice for Capillaria philippinensis infections
- Albendazole
- Mebendazole
life cycle of Capillaria philippinensis
(pls press 5 na agad hehe)
- embryonated eggs in the water are eaten by fish where they develop as larvae there
- man eats raw or undercooked infected fish which will become adults sa small intestine then gravid females will either lay typical or atypical eggs
- typical eggs will be passed sa stool then into the water (where it embryonates) then eaten by the fish ulet
- sometimes, infected fishes r eaten by migratory birds then cla eong tumatae ng typical eggs
Common name for Necator americanus
- New world hookworm
- American murderer
STH pala ‘to btw
Common name for Ancylostoma duodenale
Old world hookworm
STH pala ‘to btw
Are hookworms capable of heart-lung migration?
Yes
Habitat of hookworms?
Small intestine
Final host of hookworms
Man
Infective stage of hookworm
L3 filariform larva
Diagnostic stage of hookworm
Hookworm egg
coz larva is attached s intestine (rare sa stool)
MOT of hookworms
Skin penetration
Except for Ancylostoma duodenale which may be transmitted in an oral and transmammary manner
Which of the two hookworms are C-shaped? Cno si S-shaped?
- C-shaped = Ancylostoma duodenale
- S-shaped = Necator americanus
Dental pattern of Ancylosotoma duodenale
two pairs of teeth
Dental pattern of Necator americanus
Semilunar cutting plates
Male bursa and spicule of Ancylostoma duodenale
Bell-shaped (tripartite dorsal rays) w/ plain & bristle-like spicule
Male bursa and spicule of Necator americanus
Fan-like (Bipartite dorsal rays) w/ fused and barbed spicule
Among the two hookworms, alin ang may tripartite dorsal rays and bipartite?
- tripartite = Ancylostoma duodenale
- bipartite = Necator americanus
Which is more likely to induce IDA and is larger than the two hookworms?
Ancylostoma duodenale
where do hookworm ovas embryonate?
soil
STH cla
what do you call the cell stages present in the ova of hookworms?
blastomeres
2-8 blastomeres
In penetrating the skin, hookworm larva may cause an allergic reaction called what? This is more common with what hookworm?
ground itch; Necator americanus
Rhabditiform larva is characterized by a long oral cavity called as?
buccal cavity
mas maikli Strongyloides stercoralis
Rhabditiform larva is present with a precursor structure to a reproductive system consisting of a clump of cells in an ovoid formation. This structure is called?
genital primordium
mas prominent sa Strongyloides stercoralis than hookworm
In Harada-Mori technique, once the larva is cultured until the filariform stage, which larva will generally move downwards and which of them will move upwards and accumulate at the end of the filter paper?
Strongyloides stercoralis or Hookworm
- Move upwards = Strongyloides stercoralis
- Move downwards = Hookworm
MALAKAS KASI STRONGYLOIDES KAYA LUMALABAN S FLOW NG 2BIG
3 phases of hookworm pathogenesis
- cutaneous
- pulmonary
- intestinal
Diagnostic tests for hookworm
- DFS
- Concentration techniques
- Kato-Katz
- Harada-Mori
Pathology of hookworm
- Anemia
- Eosinophilia
- Wakana disease (pneumonitis)
- Abdominal pain
- Hypoproteinemia
Drug of choice for hookworm infections
- Albendazole
- Mebendazole
- Pyrantel pamoate
Cutaneous larva migrans wherein infective larva penetrate the skin but are unable to complete their life cycle are caused by what species of hookworms?
- Ancylostoma caninum
- Ancylostoma braziliensis
How many pairs of ventral teeth are present in dog hookworm? in cat hookworm?
3 pairs; one pair (or two)
life cycle of hookworm
own words (pls press 5 na agad hehe)
- filariform (L3) larva will penetrate skin then enter bloodstream to reach alveoli then to esophagus to small intestine
- filariform larva then will copulate sa small intestine then will release hookworm eggs sa stool then it’ll go sa soil where it will embryonate
- then hatch then rhabditiform larva
Common name for Strongyloides stercoralis
- Threadworm
- Smallest nematode infecting man
Habitat of Strongyloides stercoralis
Small intestine
Final host of Strongyloides stercoralis
Man
Infective stage of Strongyloides stercoralis
L3 filariform
Strongyloides stercoralis diagnostic stage
Rhabditiform larva (L1)
MOT of Strongyloides stercoralis
Skin penetration
pwede rin siya transmammary
Diagnostic tests for Strongyloides stercoralis
- DFS
- Entero test
- Baermann
- Harada-Mori
- Concentration techniques
Drug of choice for Strongyloides stercoralis
- Albendazole
- Ivermectin
What do you call the characteristic of Strongyloides stercoralis wherein they do not need a man to fertilize eggs?
strong ind woman - ma’am diana
parthenogenic
parthenogenesis = capable of self-fertilization
Strongyloides stercoralis are what type of parasites?
obligate or facultative?
facultative
In Strongyloides stercoralis infections, embryonated eggs may be present in stool and u can differentiate them with hookworm eggs by the mere fact that they always come with?
well-developed larvae
Pathology of Strongyloides stercoralis
- Strongyloidiasis
- Cochin China diarrhea
- Honeycomb appearance of intestine (due to embedded eggs)
- Pneumonitis
life cycle of Strongyloides stercoralis
(pls press 5 na agad hehe)
- filariform larva (L3) skin penetration
- L3 maturation in small intestine
- laying of eggs then hatch
- Rhabditiform larva (L1) may proceed to direct, indirect, or autoinfection route
- direct = rhabditiform larva in stool then mature into L3 then be infective
- indirect = rhabditiform larva in stool then mature into nonparasitic then produce eggs that will develop into rhabditiform that’ll become infective
- autoinfection = rhabditiform develop into filariform inside then autoinfect
capable of heart-lung migration
What parasite of monkeys may also infect humans?
differs morphologically from S. stercoralis in some minor aspects
Strongyloides fuelleborni
These are herbivore parasites wherein humans are accidental hosts and are similar in appearance w/ hookworms
Trichostrongylus spp
The ova of Trichostrongylus spp. is ____ than hookworm and have more pointed ends
larger or smaller
larger
Diagnostic stage of Trichostrongylus spp.
ova
Trichostrongylus infective stage
L3 - filariform larva
Trichostrongylus MOT
ingestion of larva from contaminated vegetation
Anisakis spp common name
Cod worm, Herring worm
Anisakis Final (Definitive) host
Marine Animals
Paratenic hosts of Anisakis
fish and squids
Intermediate hosts of Anisakis
Microcrustaceans
In Anisakis, humans are what type of hosts?
Accidental hosts
3 types of anisakid larva?
- Anisakis
- Pseudoterranova
- Contracaecum
Infective stage of Anisakis
L3 larva
MOT of Anisakis
ingestion of raw or undercooked seafood containing larva
Diagnostic stage of Anisakis
demonstration of larva
- by gastrocopy, surgery, or vomiting
Treatment for Anisakis infection
- Albendazole
- Gastroscopic removal of the worm
In what parasite can u observe Loeffler’s syndrome?
Ascaris lumbricoides
pneumonitis caused by larval migration
Identify the parasite based on pathogenesis
- Nocturnal pruritus ani
- Local irritation of the vagina (Vaginitis)
- Formation of granulomas aroundeggs or worms (in peritoneal cavity) which may cause chronic pelvic peritonitis
Enterobius vermicularis
Identify the parasite based on pathogenesis
- Rectal prolapse
- Abdominal pain and distention
- Anemia & Moderate eosinophilia
- blood loss of 0.005 mL per worm per day
Trichuris trichiura
Identify the parasite based on pathogenesis
- Mystery disease
- Flattening of villi
- Borborygmi
- Electrolyte imbalance
- Autoinfection may occur
Capillaria philippinensis
Identify the parasite based on pathogenesis
- Ground/Dew/Coolie itch during cutaneous phase
- Wakana disease (Pneumonitis) during pulmonary phase
- Gastrointestinal pain & diarrhea during intestinal phase
- Increased flatulence
- Anemia
Hookworms
Identify the parasite based on pathogenesis
- Cochin China diarrhea
- Honeycomb appearance of intestinal mucosa
- Duodenal ulcer/Ulcerative colitis
Strongyloides stercoralis
Identify the parasite based on pathogenesis
- Swollen belly sickness
- Swamp itch
Strongyloides fuelleborni
swollen belly = characterized by abnormal distention, respiratory distress, generalized edema, and hypoproteinemia
Identify the parasite based on pathogenesis
Creeping eruption similar to swamp itch by avian schistosome cercariae
S. myopotami & S. procyonis
Strongyloides
Identify the parasite based on pathogenesis
- Tingling throat syndrome
- Abdominal pain
- Nausea
- Peritoneal irritation
- Vomiting
Trichostrongylus
What are the two species of nematodes causing anemia?
- Trichuris trichiura
- Hookworm
Which of the nematodes can inflict eosinophilia on the human host?
- Ascaris lumbricoides
- Trichuris trichiura
- Hookworm
- Strongyloides stercoralis
Which of the nematodes have a polymyarian muscle arrangement?
Ascaris lumbricoides
more than 5 rows of muscles for locomotion
Which of the nematodes have a meromyarian muscle arrangement?
- Enterobius vermicularis
- Hookworms
between 2- 5 rows of muscles for locomotion
Which of the nematodes have a holomyarian muscle arrangement?
Trichuris trichiura
less than 2 rows of muscles for locomotion
200 worms of what nematode may cause chronic dysentery, profound anemia, and growth retardation?
Trichuris trichiura
In what nematode may u find a honeycomb appearance of the intestinal mucosa due to ulcerations caused by embedded eggs?
Strongyloides stercoralis
Due to its nature to favor immunocompromised patients, S. stercoralis is considered a/an ____ parasite.
opportunistic
80% mortality rate grabe!
What do u call the syndrome in S. stercoralis wherein the GI tract and the lungs are involved?
may also cause debilitation and death
hyperinfection syndrome
- dahil marami n involved, autoinfect nang autoinfect strongy thus hyper haha
- remember also na capable ‘to of heart-lung migration so yeah
What do u call the disease caused by Strongyloides stercoralis that involves other organs such as the liver, heart, adrenals, pancreas, kidneys, or CNS?
seen in immunocompromised patients (w/ AIDS and HTLV-1)
HTLV-1 = Human T-lymphotropic Virus type 1
Disseminated strongyloidiasis