midterms Flashcards
refer to intestinal nematodes that are
transmitted through contaminated soil,
Soil-transmitted Helminths (STHs),
soil transmitted helminths exampless
giant
intestinal round worm of man Ascaris lumibricoides, the
human whipworm Trichuris trichuria, and the human
hookworms Ancylostoma duodenale and Necator americanus.
the giant intestinal roundworm”
Ascaris lumbricoides
morphology of ascaris lumbricides
- resembles an earthworm.
- Appearing light brown or pinkish when freshly expelled from the
intestine but gradually turns white.
male a. lumbricoides
15 to 30 cm in length and 3 to 4 mm in diameter. It has a ventrally curled
tail with protruding spicules.
female a. lumbricoides
- 20 to 35 cm in length and 5 mm in diameter and has a straight pointed
posterior end. - Capable of liberating fertilized and unfertilized eggs, which are passed
out with the feces of the human host.
a lumbricoides morphology
Both sexes have tapering ends with the anterior end being thinner than
the posterior. Fine striations are visible in the cuticle. The mouth at the
anterior end has three lips, one dorsally and two ventrally located.
a. lumbricoides egg
Longer and narrower, measuring
60 to 100 um by 40 to 60 um. It
has a thinner shell with more
variable mamillated layer.
Inside is a mass of refractile
granules .
a. lumbricoides egg
Round or oval, 45 to 70 μm in length and 35 to 45 um in width, and golden
brown due to bile.
Contains a zygote that is enclosed in a thick chitin shell with an external
albuminous mamillated covering (corticated eggs). In some cases, the
outermost mamillated layer is absent (decorticated eggs).
transmisison o fa lumbri
fecal-oral, Ingestion of infective embryonated ova occur in several ways:eating, f=drinking and ingestoin
diagnosis of a lumbricoides
kato katz, direct fecal smear (DFS) and formalin-ether
concentration technique (FECT).
light, moderate and heavy infection in a. lumbricoides
Light Infection
1,000 to 4,999
Moderate
Infection
5,000 to
49,000
Heavy
Infection
≥ 50,000
commonly used microscopy-based examination of stool samples for
the presence of ova includes d
irect fecal smear (DFS) and formalin-ether
concentration technique (FECT).
treatment of a lumbricoides
benzimidazoles mebendazole (MBZ) and
albendazole (ALB).
The dose and duration of treatment depends on STH species with A.
lumbricoides generally gets treated
for 1-3 days.
a lumbricoides can cause
In cases of intestinal obstruction and rectal
prolapse,
“ the human whipworm”
Trichuris trichuria
morphology of trichuris trichuria
The adult worm resembles a whip, the anterior three fifth is very thin and
hair-like consists of a long esophagus.
The thicker posterior portion contains intestine and sex organs.
They attach to the host through their slender anterior end.
Females are larger than the male approximately 30 to 45 mm.
egg of tt
Ellipsoidal to barrel-shaped, measuring 50 to 70 um in length and 25 um in
width, and has two distinct colorless polar plugs.
It has a double shell with a bi stained outer layer.
treatment of trichuristrichuira
benzimidazoles mebendazole (MBZ) and
albendazole (ALB).generally gets treated for 1-3 days.
infection rate of trichuris trchiura
Light Infection
1 to 999
Moderate
Infection
1,000 to 9,999
Heavy
Infection
≥ 10,000
hook worms
Ancylostoma duodenale, Necator americanus
a. duodunale morphology
Often reddish color when passed due to ingested blood. The mouth is on
the dorsal surface with two hook like teeth on the top and two triangular
cutting plates on the bottom.
n. americanus characterist8ics
Slightly smaller, the mouth has no teeth but with four chitinous cutting
plates, two each on the ventral and dorsal surfaces.
hookworm morphology
Adults have a creamy-white tough cuticle, a prominent anterior hook, and a
large oval bui capsule with specialized structures to aid in feeding.
hookworm ova characteristcics
Morphologically indistinguishable under light microscope. Their eggs are oval-shaped,
colorless, and thin-shelled, measuring 55 to 70 um in length and 35 to 42 um in width. Fresh
stool contains eggs with developing embryo in the early stages of cleavage (2-8 cells).
transmission of hookworm
- skin penetration
- translactational
- percutaneous transmission
diagnosis and treatment o hookworm
kato-katz technique (K-K),slides should be read within
30 to 60 minutes after preparation,
infection rate of hookworms
Light Infection
1 to 1,999
Moderate
Infection
2,000 to 3,999
Heavy
Infection
≥ 4,000
female e. vermicularis
generally longer and wider,
measuring 8-13mm long and 0.3-
0.5mm wide
In the posterior part, female
possess a sharp and long-tail
male e. vermicularis
Adult male
2.5mm long and 0.1-0.2mm wide
have a blunt and curving tail
with a distinct copulatory
spicule
common in male and female e. vermicualris
three labia and cephalic expansions called alae in the anterior region near
the mouth are observed in both male and female adult worms
egg of e. vermicularis
Eggs are elongate to oval, asymmetrically flattened on
one side and almost colorless, with a sticky surface
covered with an albuminous layer, a thin hyaline layer,
and an embryonic membrane, with a size of 50-54
micrometers (um) in length by 20-27 pm in width usually
deposited in the perianal region of its human host in
clumps or groups.
A gravid female E. vermicularis may deposit
approximately
4,600 to 16,000 eggs
e vemricularis mature as adult worms
which may take
15-43
days from the time of
ingestion
is when a human directly
ingests the eggs from the perianal area by fingernail
contamination while
Autoinfection
when eggs hatch into larvae in the perianal
region and the larvae migrate back to the intestine.
Retroinfection
PATHOLOGY OF ENTEROBIASIS IS ASSOCIATED WITH THREE
MAJOR CAUSES:
damage caused in the intestine because of feeding on the intestinal mucosa
and gut bacteria
damage from extraintestinal migration
irritation from egg disposition in the perianal region
diagnosis of e. vermciualris
scotch tape or anal swab technique
scotch cellulose tape
one adhesive side
that is looped can be
used to collect pinworm
eggs on the perianal skin
antihelminthic drugs used to treat enterobiasis
albendazole, mebendazole, and pyrantel pamoate
“Rat Lungworm
ANGIOSTRONGYLUS
CANTONENSIS
A female A. Cantonensis
can lay up
15,000 eggs
daily
egg od a cantonensis
Eggs measure 46 to 48
μm long and 68 to 74 μm
wide.
They are unembryonated
when oviposited.
FEMALE A. CANTONENSIS
Ranges from 17 to 33 mm long and 0.28 to
0.5 mm wide
Female intestines were intertwined with
uterine tubules giving barber pole
appearance
The posterior end of the female worm is
blunt shaped.
MALE A CANTONENSIS
Ranges from 15 to 22 mm long and 0.25 to
0.35 mm wide
Males have a developed caudal bursa and
have spicules
A CANTONENSIS TRANSMISSION
Although the mechanism by which humans get infected is not yet clear,
transmission of A. Cantonensis is usually attributed to:
PATHOGENESIS AND TRANSMISSION
ingestion of the raw mollusk infected by the definitive host ingestion of leafy vegetables contaminated with mucus secretion of the mollusk
ingestion of paratenic host, such as freshwater prawns or crabs
drinking contaminated water
Presence of the A. Cantonensis in human body may lead to variety of clinical manifestations called Angiostrongyliasis
Symptoms incudes headaches, stiffness of neck, vomiting, fever, paralysis and tremors
Eosinophilic Mengitis, shows the presence of this worm in our body, it alsoincreases CSF and eosinophils (WBC).
A CANTONENSIS CAUSES
causative agent of eosinophilic meningoencephalitis
A CANTONENSIS diagnosis
dot-blot ELISA and immuno-
polymerase chain reaction (PCR)
a cantonensis reatment
no anthelminthic treatment established against A.
Cantonensis infection although it is possible to treat the infection at early
stage through the following:
Treatment
Thiabendazole
Combination of corticosteroids and mebendazole
CSF withdrawal
Surgery (for ocular angiostrongyliasis)
Intestinal Capillariasis Location
: Mucosa of small intestine
Intestinal Nematodes: Pudoc Worm
CAPILLARIA
PHILIPPINENSIS
ova of capillaria philipinensis
(Produced by oviparous female)
Peanut shaped
Has striated sheath
Flat bipolar plugs
disease of capillaria philipinensis
DISEASE: Intestinal Capillariasis
(hardening,
inflammation of mucosa, dissapearance of mucosal glands,
degeneration of intestinal vili)
chronic malabsorption-diarrhea syndrome
`trichonella spiralis disease
trichinellosis
diagnosis of trichinella spiralis
antibody detection or muscle biopsy
treatment of t spiralis
400mg of albendazole oral twice a day 8-14 days. mebendazole, 200-400mg first 3 days of treatment increase in following 10 days of treatment
filiarial worms disease
lymphatic filariasis
firlarial worms example
[Wuchereria bancrofti] [Brugia malayi] [Brugia timori]
human disease caused by parasitic roundworms
Lymphatic filariasis
by parasitic roundworms
filarial
worms.
The main manifestation of this disease is the impairment of the lympathic system which leads to
the abnormal enlargement of body parts, which causing pain, severe disability and social stigma
for the affetted individual.
filarial wormms
thickened and
hardened skin and fluid retention,
leading to painful, swollen and enlarged
body parts.
Elephantiasis
characteristics of wucheria bancrofti
The female worms measure 80 to 100 mm in length and 0.24 to 0.30 mm in diameter.
The females are viviparous.
Adults produce microfilariae measuring 244 to 296 μm by 7.5 to 10 μm, which are sheathed
and have nocturnal periodicity.
The life span of the adult worms is long, probably several years (5-10 year or even more).
treatmet of filarial worms
Diethylcarbamazine (DEZ), Ivermectin, albendazole, diethylcabamazine citrate
the only two
species belonging to the family lymenolepididae that are
known to infect man.
Hymenolepis nana and H. diminuta
man. Hymenolepis nana is commonly referred to as
the
dwarf tapeworm
while Hymenolepis diminuta is known as the
.
Rat tapeworm
characteristics of h. nana
Small species, rarely exceeding 40 mm in
length.
Scolex with 4 suckers, and a short
retractable rostellum armed with hooks.
Segments wider than long, unilateral
genital pores, and each mature proglottid
contains three testes.
Gravid proglottid disintegrates, releasing
immediately infectious round to oval eggs.
hymenolepis diminuta characteristics
Larger than H. nana, measuring up to 90 cm.
Scolex with 4 suckers, and a rostellum
without hooks.
Segments wider than long, unilateral genital
pores, and each mature proglottid contains
three testes.
Gravid proglottid disintegrates, releasing
non-immediately infectious round to oval
eggs larger than H. nana.
Requires an arthropod intermediate host in
its life cycle.
trasmission of h. nana and h.. diminuta
autoinfection and accidental infection
Three species causing taeniasis in humans:
Taenia solium, T. saginata, and T.
asiatica.
taenia solium common named
Pork Tapeworm
taenia saginata common name
beef tapeworm
characteristics of t solium
Size: Adult worms are relatively small, ranging from 2 to 4 meters in length.
Scolex: Features a small, rounded scolex with four suckers and a rostellum armed
with hooks.
Proglottids: The mature proglottids are wider than they are long and contain a
uterus with 7 to 11 lateral branches, each ending in an egg.
Genital Pore: Located laterally on mature proglottids.
Eggs: Oval-shaped, with a radially striated shell.
characteristics of t saginata
Size: Adult worms are larger, ranging from 4 to 10 meters in length.
Scolex: Features a larger, rounded scolex with four suckers but lacks a rostellum
or hooks.
Proglottids: Mature proglottids are longer than they are wide and contain a
uterus with 12 to 32 lateral branches, each ending in an egg.
Genital Pore: Located medially on mature proglottids.
Eggs: Oval-shaped, similar to T. solium, with a radially striated shell.
characteristics of t asiatica
Size: Similar in size to Taenia saginata, ranging from 4 to 8 meters in length.
Scolex: Resembles the scolex of Taenia saginata, featuring four suckers but
lacking a rostellum or hooks.
Proglottids: Morphologically similar to T. saginata, with mature proglottids being
longer than they are wide, and a uterus containing multiple lateral branches.
Genital Pore: Located medially on mature proglottids.
Eggs: Oval-shaped, similar to T. solium and T. saginata, with a radially striated
shell.
TREATMENT of taenia
praziquantel. niclosamide, alvendazole
sign and symptom of taenia acute
nause, c=vomitting, abdominal pain
insigns and symptoms of taenia itermediate
Mild Gastrointestinal Symptoms:
digestive issues and discomfort
signs and symptoms chronic
proglottid passage, gastrointestinal symptoms (digestive discomfort and weight loss), nutritional deficiency, allergic reaction
sign and symptom of taenia chronic
nuerocytecirosis
diagnosis of taenia
1.Stool Sample Examination:
2.Gravid Proglottids and Scolex Examination
3.PCR and Restriction Enzyme Analysis (REA)
LABORATORY
treatment of taenia
praziquantel, niclosamide, aldbendazole
most common tapeworm
commonest species being Diphyllobothrium latum
the definitive hosts ofD. latum
are humans and other fish-eating mammals
may also cause pernicious anemia andvitamin B12deficienc
d. latum
characterstics of d. latum
Scolex – elliptical, spatula-like, or almond in shape
About 2-3 mm long and provided with a pair of linear muscular grooves (bothria)
Uses this as a means of attachment to the host (small intestine) by muscular tonus (muscle tension) of its strobila (segmented body). It is composed of proglottids (segments), each carrying two different sex organs.
The uterus is a bilobed structure that loops, extending from the ovary to the uterine pore on the midventral surface of the segment, through which the mature proglottids release the eggs.
Anapolytic – no detachment of proglottids from the strobila
egg of d latum
Eggs: are ovoid, golden-brown, and have an operculum at one end with a small thickening of the shell at the opposite end.
Measures 58-76 um by 40-51 um
Fully developed eggs are discharged in the uterine pore
Terminal proglottid gradually becomes exhausted and disintegrate (not gravid)
larva of d latum
Larva: has three stages
First stage larva: Coracidium
Second stage larva: Procercoid (found inside the copepod crustacean, e.g., Cyclops)
Third stage larva: Plerocercoid (found inside the musculature of freshwater fishes)
Both Procercoid and Plerocercoid lacks a bladder.
intermediate host of d latum
1st intermediate host copepads: diaptomus spp, cyclops spp
2nd intermedidate host:fresh braking water fish, salmonoid fish
condition characterized by enlarge red blood cells
macrocytosis
(anemia and neurological problems associated with vitamin B12 deficiency) 80% is said to be consumed by the tapeworm
Bothriocephalus anemia
diagnostic stage of d latum
egg with operculum or segments showing genital pores
diagnostic tool of d latum
stool examination, cytochrome c oxidase subunit 1, tRNA Pro, tRNA Ile, tRNA Lys, NADH dehydrogenase, and cytochrome b gengenes for accurate speciation of D. latum
treatment of d latum
praziquantel, niclosamide, gastrografin
domestic dogs and
cats generally found in warmer and more
humid regions of Canada, such as
southern coastal BC.
dIpyllidium caninum
diagnosis of d caninum
flotation method
treatment of d caninium
praziquantel, epsiprantel
(Lung Fluke)
Paragonimus
Westermani
tropical disease caused by lung flukes
of the genus Paragonimus
Paragonimiasis
diagnosis of p. westermani
katoo katz technique,Ziehl-Neelsen Staining (ZNS), Sodium Hydroxide (NaOH) Concentration Technique
treatment of p westermani
praziquantal, triclabendazole
B L O O D F L U K E S
Schistosoma
japonicum
diagnosis of schistosoma japonica
circum-oval precipitin
test (COPT),dipstick dye immunoassay (DDIA), Rectal biopsy
Ultrasonography
Molecular methods
Treatment & Prevention OF SCHISTOSOMA JAPONICUM
Praziquantel (PZQ)
ArtemetherQ
Zipper Tapeworm
SPIROMETRA SPP
TREATMENT FOR SPIROMETRA SPP
PRAZIQUANTAL, SURGICAL REMOCAL, THERAPIE
occurs with other
helminths that can be detected in fecal samples, such as the soil-transmitted helminths Ascaris
lumbricoides, Trichuris trichuria, hookworms, and food-borne trematodes
Schistosoma
japonicum
- causative agent of schistosomiasis japonica
S. japonicum-
biggest of all
blood flukes;
S. Japonicum
usually found
held in the gynecophoric canal of the male,
S. Japonicum female
broadly ovoidal in shape with very characteristics of cellular
debris, ova has a rudimentary or abbreviated lateral spine, shell stained acid-fast,
sloping shoulder miracedium inside
ova of s. japonicum
Ribbon-like/white bandage
appearance.
spirometra spp
