Phylum Nematoda Flashcards
most abundant animal on earth
Roundworms
male and female worm
Dioecious
True or False : male is longer than female worm
False
Round worms are __________,_________ and _________.
Free living in soil, marine and freshwater habitat
How many species does roundworms has?
500,000
Nonsegmented, cylindrical, tapered at both ends
Roundworms
BODY COVERING: cuticle with longitudinal muscles
Roundworms
BODY CAVITY: (pseudocoel)
complete digestive tract with both oral and anal openings.
Roundworms: Mouth is provided with
spines, hooks, cutting plates, stylets, or other structures for attachment or penetration of tissue
Roundworms : Reproductive organs are
are tubular and lie coiled in the body cavity.
Roundworms fertilization is __________
Internal
In male roundworm they have _________ for copulation.
Chitinized spicules
Separate classes of nematodes
Aphasmidea
Phasmidea
Papillae:
Sensory hairs at the head and tail
_________:________ end (amphids),
posterior end caudal (_______) nerve endings
that act as chemoreceptors.
Sensory organs
Anterior end caudal
Phasmids
Life cycle:
Egg stage
Larval stage
Adult age
Adult females:
Oviparous
Vivaparous
Parthenogenetic
Aphasmids
Trichinella spiralis
Trichuris trichiura
Capillaria philippinensis
Phasmids
Ascaris lumbricoides
Strongyloides stercoralis
Hookworms
Enterobius vermicularis
Filarial worms
Habitat: small intestine
Ascaris lumbricoides
Strongyloides stercoralis
Hookworms
Capillaria philippinensis
Trichinella spiralis
Habitat: large intestine
Trichuris trichiura
Enterobius vermicularis
Habitat: Tissue nematodes
Trichinella spiralis
Wuchereria bancrofti
Brugia malayi
Onchocerca volvulus
Loa loa
Dirofilaria immitis Gnathostoma spinigerum
Habitat: larva migrans
Dracunculus medinensis
Angiostrongylus cantonensis
Ancylostoma caninum
Ancylostoma braziliense
lays eggs, often excreted outside the host through the stool
Oviparous
Example of oviparous
Ascaris
Trichuris
forms eggs within the parasite,
then births larvae instead of eggs within the host
Viviparous/Larviparous
Example of viviparous
Plasmodium
can produce an offspring without the male
Parthenogenetic
Example of parthenogenetic
Strongyloides
Psuedocel
Complete digestive tract with both oral and anal opeings
Parasite of the carnivorous mammals
Trichinella spiralis
Smallest nematode parasite of humans
Trichinella spiralis
Trichina worms is
Minute and threadlike
Trichinella is common in _______, ________ and _______
Rats, Swine fed with uncooked garbage, slaughterhouse scraps
Trichinella occur ________
Worldwide or cosmopolitan
Trichinella spiralis occurs in areas where __________
garbage containing pork scraps is fed to hogs
______ has the highest incidence report of trichinella spiralis
China
Genral characterisitcs of trichinella spiralis
Viviparous
These countries als reprted incidence rate of trichinella spiralis
France
Yugoslavia
Italy
Spain
Middle east
Africa
Infective stage of trchinella spiralis
Larva
Size of male adult worm
less than 2mm long (1.4-1.6mm x 40-60 μm)
_______ is found at caudal end which is evertible during coitus. → It is guarded by 2 conspicuous
______ which clasp
the female during copulation
Cloaca
conical papillae
In trichinella s male adult worm ______ is absent
Spicule
Trichinella spiralis posterior end is ________
Curved ventral
Sze of trichinella s female adult worm
less than 5mm (3-4mm x 60-80 μm)
______ opens at the anterior fifth of the body
Vulva
Single______ which contain the larva
Single_______ found near the posterior end. (caudal)
Uterus
Ovary
Size of the larva of trichinella spiralis
80-120μm x 5-6μm (100x6μm)
Larva excyst after the cyst are digested and
penetrate the im- develop to adult _______
(30-40 HRS)
diseases of trichinella spiralis
trichinosis
trcihiniasis
trichinellasis
MOT of trichinella spiralis
ingestion of carcasses with encysted larva (infected stage)
diagnostic test of trichinella spiralis
skeletal muscle biopsy
serologic test
Treatment for trichinella spiralis
● Mebendazole
● Thiabendazole
● Albendazole
● Prednisone
prevention and care for trichinella spiralis
Cook meat properly
Maintain proper sanitation
Education - public
clinical features of trichinella spiralis
- Mild to moderately severe symptoms within 2-7 days after ingestion.
→ gastroenteritis, diarrhea with or without abdominal pain for several weeks, weakness - Fever and eosinophilia, leukocytosis is common but not always present
- Clinical sign – circumorbital edema(eyelids) appear on the 7th day
→ photophobia, diplopia, and other visual disturbances. - Vasculitis – splinter hemorrhages underneath the nails.
- Muscle pain – (myalgia) sensitive to pressure
- CNS involvement-psychosis, meningoencephalitis, cva, brain tumor
- Myocarditis, pneumonitis
trichuris trichuria appearance is like a
whipworm
Trichuris trichuria:
-ANTERIOR 3/5 is very _________ houses the
esophagus.
-POSTERIOR 2/5 is thick and stout resembling the handle of a whip which houses the __________________
-thin and hair-like,
-intestine and reproductive organs
world wide distribution nematodes
ascaris l
trichuris trichuria
trichinella spiralis
Worldwide distribution (cosmopolitan) but common in tropical countries and in regions where sanitation is poor
trichuris trichuria
what is the Prevalence rate of trichuris trichuria in asia?
50-80%.
infective stage of trchuris trichuria
ova
what is the adult life span of male adult worm in trichuris?
1 year
the female adult worm of trichuris produces ______ eggs daily
3,000-20,000
what is the shape of the ova of the trichuris
Barrel – football-shaped in feces
the ova is similar to hookworm
strongyloides
color of the ova of trichuris
golden brown
Intralaminar (refractile) prominences usually
referred to as ______ at either end.
polar plugs
3 shells of trichuris
- chorionic layer,
- albuminous layer,
- bile-stained layer
trichuris requires _____ weeks in soil to mature
3
whatis the disease off trichuris
trichuriasis
clinical feature of trichuris
- Asymptomatic-light infection
- Abdominal pain, distension, appendicitis
- Bloody or mucoid diarrhea
- Tenesmus (distressing urge to evacuate), weight loss and weakness - heavy infection
- Rectal prolapse (edematous rectum)
- Moderate eosinophilia
- Nutritional deficiency - stunted growth
diagnostic test for trichuris
DFS - Direct Fecal Smear
Kato-Katz
FECT (Formalin-Ether Concentration Test)
treatment of trichuris
● Mebendazole
● Albendazole
● Piperazine citrate
● Pyrantel pamoate
● Loperamide hydrochloride
(Imodium)
prevention and care of trichuris
Proper hygiene - hand washing
Proper sanitation - disposal of feces
Avoid using fecal matter as fertilizer
Education - public
circumorbital edema(eyelids) appear on the ____
7th day
edematous rectum
rectal prolapse
It was first recognixed in the philippines during ___
capillaria philippinensis
1963
first patient is located at _____
bacarra, ilocos norte
reservior host of the capillaria
migratory birds
intermediate host of capillaria
fish
___ - epidemic of capillaria in __________. where ____ became ill and ___ died
-1967
-pudoc, west tagudin, ilocos sur
-1,300
-90
in capillaria adult worms are usually ______
slender anteriorly and stout posteriorly but tapering is gradual and less pronounced.
capillaria occurs also in ?
philippines
egypt
taiwan
japan
iran
columbia
korea
capillaria occurs also in ?
philippines
egypt
taiwan
japan
iran
columbia
korea
it contributes to the transmission in capillaria
freshwater fish are eaten raw
hepatic capillariases
c. hepatica
c.aerophilia
pulmonary capillariasis
what is the copulatory organ of male adult worm of capillaria
spicule
Spicule protrudes through a
refractile penial sheath which has a bulbous termination covered with small recurved spines.
male adult worm (capillaria)
2 types of female adult worm of capillaria
larviparous
oviparous
(population build up)
▪ will repopulate species inside the host
larviparous
(infection)
▪ will repopulate outside the host
oviparous
shell is thick with striations hence peanut shape.
c. philippinesis
Similar to trichuris egg but smaller and more oval in shape with ______ but are NOT protuberant
ova of capillaria p.
bipolar mucous plugs
disease of c. philippinesis
instestinal capillariasis
clincial features of c. philippinensis
- Abdominal pain
- Borborygmi
→ gurgling of the stomach - Loss of wieght
- Vomiting
- Edema
- Hypoproteinemia
→ malabsorption due to destruction of intestinal wall
diagnostic test of capillaria
- Direct Fecal Smear - eggs are passed out in feces
- Identification of larva and worm in stool
treatment for cp
● Mebendazole
● Albendazole
● Fluid and electrolyte + high protein diet
prevention and care for cp
- Proper cooking of fresh water fish (IH)
- Proper sanitation and disposal of feces
_______ can be found in the _________________________ areas of the globe, under
conditions of poor sanitation and where feces are used for
fertilizers.
ascaris lumbricoides
temperate and tropical
ascaris also known as _______ tribute to its resemblance to earthworm
giant intestinal round worm
infective stage of ascaris
ova
diagnostic stage of ascaris
unfetilized and fertilized egg
in male adult worm of ascaris it has a terminal mouth with ___ lips w/a sensory papillae
3
male adult worm of ascaris have ventrally curved posterior end with ____
2 spicules
female adult worm of ascaris can lay _____ eggs/day
200,000
found only in the absence of male
unfertilized egg
true or false: unferlitized egg is more elongated than fertilized egg (ascaris)
true
fertilized can hatch the larva within ___
14 days
Outer albuminoid coating coarsely mamillated
which may be absent (decorticated)
fertilized
Thin shelled w/ mammillated irregular coat filled
with refractile granules
unfertilized
diseases of ascaris
-Ascariasis,
- Ascaris pneumonitis (Loeffler’s pneumonia/endocarditis/ syndrome),
- eosinophilic
pneumonia (parasitic infection)
MOT of ascaris
Ingestion of fertilized ova - Infective stage (ST)
clinical features of ascaris
- Bowel obstruction or obstruction of other organs (appendix) in heavy infection
- Asthma, pneumonitis - due to migration of the juvenile worm to the lungs
- Cardiac damage - eosinophilic granular proteins (lysozymes)
- Fever, malaise
- Abdominal distension and tenderness, vomiting
diagnostic test of ascaris
● Direct Fecal Smear - eggs
● Kato-katz
● Recovery of worms in stool, sputum
● Radiographic images may also reveal their presence
treatment of ascaris
● Mebendazole
● Albendazole
● Pyrantel pamoate
● Piperazine citrate
prevention and care for ascaris
- Proper hygiene -handwashing
-Proper sanitation - disposal of feces
-Avoid using fecal matter as fertilizers
-Education - public
THREADWORM
strongyloides
Occurs in the tropical and subtropical areas of abundant rainfall. Loose sandy loam soil, ambient temperature.
strongyloides
strongyloides is not parsitic by nature but only an ______
accidental parasite
female adult worm of strongyloides has _____-
Free-living generation=male & female; parasitic generation=
parthenogenetic females
male worms of strongyloides is ____ from the body early in the infection
eliminated
definitive hosts of strongyloides
man
cat
dogs
other mammals
true or false: Prevalence rate is higher compared to hookworm infection.
false
infection may persist due to ____(strongyloides)
autoinfection
male adult worm of strongyloides
● 0.7mm x .04 mm
● Free-living
● Smaller than the females
● Ventrally curved tail with
2 copulatory spicules a
gubernaculum
● NO caudal alae (wings)
● Does not persist in the
host because they are
killed by female worm
that enters the host
free living female adult worm of strongyloides
● 1 mm x .06 mm
● Free-living; smaller than the parasitic
● Muscular double-bulbed esophagus
and the intestine is straight cylindrical
● Found in soil
female adult worm parasitic (strongyloides)
● 2.2 mm x .04 mm (longer)
● Colorless, semi-transparent, with
finely striated cuticle
● It has slender tapering anterior end
and a short conical pointed tail
● Short buccal cavity w/ long slender
esophagus that extends 1/4 of the
body, intestine is continuous to the
anus
● Vulva is located 1/3 the length of the
body from the posterior end
● The uteri contain a single file 8 to 12
thin shelled, transparent, segmented
ova
● Parthenogenetic
● Found in the host
2 types of larva in stongyloides
rhabditiform larva (1st stage)
filariform larva (2nd stage)
Similar to HW but smaller with a distinct cleft
(notched) at the tip of the tail
filariform larva
definitive host of strongyloides
humans
monkeys
disease of strongyloides
strongyloidiasis
MOT of strongyloides
Skin penetration (similar to hookworm)
clinical features of strongyloides
- Lesions – intense itching at the site of penetration
- Pneumonitis – migration of worm to the lungs; similar to ascaris because the young/luminal worm will
travel to the lungs - Moderate to severe diarrhea
- Malabsorption syndrome with steatorrhea (feces with a lot of fat)
- Malnutrition – worm prevents fat absorption
- Ulcers – LGIT and UGIT – bleeding
- Hyperinfection – AIDS or immunocompromised parts
- Transmitted – mammary glands, organ transplant
diagnostic test of strongyloides
● Identification of larva in stool
● Sputum exam
● Direct Fecal Smear (DFS)
● Formalin-Ether Concentration Technique (FECT) – usually breaks the cell wall of ova
● Baermann technique (CH 14 pg. 407) – culture ova to hatch larva; larva will form filariform larvae and
identify the type of parasite
● Agar plate method
T/P/C of strongyloides
● Albendazole
● Ivermectin
Proper sanitation- disposal of feces
Avoid walking barefooted on soil
infective stage of strongyloides
larva and ova
Most common helminth parasite of the temperate regions but, common to tropics and sub tropics region
enterobius vermicularis
______ Found in families of _________ where
sanitation levels are relatively rigorous
enterobius vermicularis
high socioeconomic status
_______ spread is facilitated by crowded indoor living in
temperate climates- ______
enterobius vermicularis
orphanages, hospitals, sanitariums.
enterobius vermicularis also known as _______
pinworm
seatworm
oxyrius
_______ caused no disfiguring or debilitating effects
but, their presence is an embarrassment and irritation
pinworms
The ova is very light and can easily be transported in the
air
enterobius vermicularis
They are rarely seen because
they die after copulation
male adult worm of enterobius
● Females dies soon after oviposition
● More females than males in the host
female adult worm of eneterobius
Translucent shell consists of an Outer triple
albuminous layer (mechanical protection),
Inner lipoidal membrane (chemical protection)
ova of enterobius vermicularis
true or false: the ova of enterobius vermicularis live longest under conditions of fairly LOW humidity and moderate temperature
false (high)
Feature: Asymmetrical with one side flattened and the other convex similar to
letter P
OVA OF ENTEROBIUS VERMICULARIS
DISEASE OF ENTEROBIUS
● Enterobiasis
● Oxyuriasis
● Ova- infected stage-ingestion/ retroinfection
MOT of enterobius
ingestion of ova
clinical features of enterobius
- Pruritus ani – migration of female worm to the anus during the resting state-itching; intense itchiness in
the anal area - Vaginal migration – causing irritation
- Appendix, liver, lungs
- Retrofection/ Autoinfection
● Cellophane tape swab – recovery of ova in the perianal region
● Usually performed before bowel movement or taking a bath
diagnostic test for eneterobius
treatment for enterobius
● Mebendazole
● Albendazole
● Pyrantel pamoate
prevention/care of enterobius
-Quarantine/ Tx for entire members of the family- disinfect
contaminated fomites(clothings, beddings, towels,etc.)
-Proper hygiene-washing of hands
-Education-family