Nematodes to end table

Nematodes

True roundworms with separate sexes; dioecious.

females are larger

males are generally shorter and slimmer

NEMATODES: Sexes are separate and the females are ___ than males

1) the egg stages or the ova

2) larval stage

3) the adult stage

Life cycle NEMATODES

Unsegmented, elongated, and cylindrical in shape

NEMATODES GENERAL CHARACTERISTICS:

thick, flexible multi-layered collagenous cuticle

Nematodes are covered with

anthelmintic property

Nematodes: the cuticle is used to test the ___ of a plant extract by seeing if it has been damaged by the plant extract in question

- impermeable cuticle (chitinous-like)

mouth, buccal cavity, esophagus, intestines, rectum, anus

Nematodes: Possesses a complete digestive tract

pseudocoel

Nematodes: Possess body cavity

digestive, excretory, nervous, reproductive organs

Nematodes: lined with muscle fibers and contains viscera

SOIL TRANSMITTED

VECTOR TRANSMITTED

CONTACT TRANSMITTED

FOOD BORNE

Nematodes SOURCES OF EXPOSURE TO INFECTION

Ascaris lumbricoides

Strongylodes stercoralis

Necator americanus

Ancylostoma duodenale

Tricuris trichiura

Nematodes: STH GROUP (SOIL TRANSMITTED HELMINTH GROUP)

Wuchereria bancrofti

Brugia malayi

Nematodes: VECTOR TRANSMITTED GROUP

Enterobius vermicularis

Nematodes: CONTACT TRANSMITTED

- not necessarily sexual contact, as it can be acquired by direct close contact.

ingestion

Inhalation is also one way of getting the parasite, e.g., inhaled from a dirty linen.

Enterobius vermicularis default mode of transmission is through __ .

Trichinella spiralis

Capilllaria philippinensis

Angiostrongylus cantonesis

FOOD BORNE nematodes

Consuming contaminated meat (zoonosis)

Trichinella spiralis is transmitted by

Consuming contaminated fish

Capilllaria philippinensis is transmitted by

peanut - shaped with flattened mucus plugs

Capilllaria philippinensis Ova is

Capilllaria philippinensis

What causes Borborygmus ( gurgling of the stomach )

Consuming contaminated fruits and vegetables or snails .

Angiostrongylus cantonesis is transmitted by

ASCARIS LUMBRICOIDES

Tri - radiate lips , triangular buccal cavity

ASCARIS LUMBRICOIDES

Most common helminth infection

Embryonated egg

Most infective stage of Ascaris lumbricoides

pigmented and fully developed larva

Ascaris lumbricoides Embryonated egg Contains:

Fertilized egg

Ascaris lumbricoides stage that Only contains egg yolk

Fertilized egg

Ascaris lumbricoides Not yet embryonated

small intestine .

Ascaris lumbricoides become a matured worm in the __

an increase of eosinophil levels is observed due to the constant migration of the worm .

What do you think is the effect of the presence of ascaris infection to the eosinophil level of the blood ?

warm , wet climates

Ascaris lumbricoides Geographic prevalence highest in

200,000 eggs / day

Ascaris lumbricoides : 1 adult female ____ eggs / day

No , it may be statistically low , but it is significant .

: Is it normal for a child to have at least 1 ascaris lumbricoides in the small intestines ?

Decorticated egg

ascaris lumbricoides No albumin layer

Corticated

ascaris lumbricoides With albumin layer ; non- infective stage

it's ovoid granules are coarse and disorganized

How to distinguish Unfertilized egg ascaris

has a solid mass in the middle and round in shape

How to distinguish Fertilized egg ascaris

embryonated egg

Ascaris: only the __ can infect you .

Albendazole

Mebendazole

DRUGS GIVEN TO TREAT A. LUMBRICOIDES:

ENTEROBIUS VERMICULARIS

Cephalic alae

Plano - convex ova ( D - shaped

ENTEROBIUS VERMICULARIS ova shape

ENTEROBIUS VERMICULARIS

Most common worm infection in the US

Familial infection

seat worm or society worm because it can easily spread

ENTEROBIUS VERMICULARIS aka

smaller and the posterior end is curved

ENTEROBIUS VERMICULARIS male worms

bigger and the posterior end is pointed

ENTEROBIUS VERMICULARIS female worms

die

ENTEROBIUS VERMICULARIS: When the male fertilizes the female, it will__ . Then, the female will develop and produce eggs.

perineal cove

The eggs will be laid in the __ and not in the intestines because the female worm requires atmospheric air to stimulate egg laying.

perianal pruritis

scratching of the perianal and perineal region due to an itchy feeling because of the eggs

CELLOPHANE TAPE/ PERIANAL SWAB

DIAGNOSIS

CELLOPHANE TAPE/ PERIANAL SWAB

Only done for toddlers only

CELLOPHANE TAPE/ PERIANAL SWAB

the sticky portion is placed outside the tongue depressor, and it will swab the perianal cove.

- This is done before taking a bath or bowel movement.

6 hours

The collector must wear his/her mask and gloves properly to avoid exposure. Especially since after ___ hours of oviposition, it is now highly infective.

V-shaped

characteristic of e. Vermicularis egg

grade 3 students (9-10 years old)

CELLOPHANE TAPE/ PERIANAL SWAB: The best age group to represent to this kind of testing would be

TRICHURIS TRICHIURA

Whipworm

TRICHURIS TRICHIURA

Often seen in conjunction with Ascaris

Ascaris

if we see Trichuris trichiura we will look and search further to see if there is __ because it could be present also because they have common requirements for development , type of soil , mode of transmission , etc.

1 year

Trichuris lives longer than Ascaris . Ascaris can only have a life span of __ while Trichuris can last for 3 years .

Trichuris trichiura

characteristic Japanese lantern egg football shaped egg or barel shaped with protruding bipolar mucus plugs , lemon - shaped egg .

our cecum (a pouch within the peritoneum that is the beginning of the large intestines).

If it is a pure Trichuris trichiura infection with no other mixed infections, they are just confined sometimes in our ___

fleshy posterior end and an attenuated anterior end

It is called whipworm because of its characteristic __ & __ , like the handle of a whip.

male

If the posterior end of the worm is curved, it is__.

female

if the posterior end is pointed, it is__.

rectal prolapse.

There is no stool but it will cause you to feel like you have stool and therefore, exert force to excrete it out and push harder. And because of that, the rectum will be pushed out, which we now call

TRICHURIASIS

RECTAL PROLAPSE FROM

Necator americanus

Ancylostoma duodenale

THE HUMAN HOOKWORMS

semilunar cutting plates

Necator americanus Dental pattern :

Necator americanus

Ancylostoma duodenale

Soil transmitted and blood sucking helminth

Necator americanus

S - shaped body curvature

opened mouth feeding stage , short and stout

Necator americanus Larvae Rhabditiform

closed - mouthed non - feeding stage , thin and slender

Necator americanus Larvae Filariform

2-8 cell stage ( cannot be differentiated with A. duodenale )

Necator americanus Ova :

two pairs of tru ventral teeth

Ancylostoma duodenale Dental pattern :

Ancylostoma duodenale

C - shaped body curvature

open-mouthed feeding stage, short and stout

Rhabditiform from Ancylostoma duodenale Larvae

closed-mouthed non-feeding stage, thin

and slender

Filariform Ancylostoma duodenale Larvae

2-8 cell stage (cannot be differentiated by N.

americanus)

Ova: Ancylostoma duodenale

Ancylostoma duodenale can suck more blood because it has teeth.

They suck blood continuously and change position every hour. Blood does not clot because they have naturally occurred anticoagulants in their oral cavity.

They also have hemoglobinase that will metabolize blood to be their source of nutrients.

Therefore, if you are experiencing a heavy infection with hookworms, the patient will also suffer from anemia.

With these two parasites, which species can suck

more blood or can cause anemia/a more serious anemia?

The anemia should be treated first because it can be fatal if not is not good or is weak. If the patient has cough, colds, or fever, the patient is improving it. Likewise, we treat the anemia first before treating the

hookworm infection.

If the patient has severe anemia due to

hookworm, which one is to be treated first, the hookworm infection or the anemia?

Skin penetration.

mode of transmission of hookworm?

Ground itch

Pneumonia

INFECTION DUE TO LARVA : HUMAN HOOKWORMS

Wakana disease or Hookworm pneumonitis.

If the pneumonia is due to hookworm, it is what we call

Loefflers disease/Ascaris pneumonitis.

If pneumonia is caused by Ascaris, it is called __

Iron deficiency anemia/anemia

INFECTION DUE TO ADULT

bursa or copulatory bursa

On the lower part of the male worm, there is fan-like extension which we call __ and is used for copulation.

egg cell stages (blastomeres)

The eggshell is transparent and inside the egg are

__ which are consistent in hookworms.

Hookworms, Taenia, Fasciola, Heterophyids

Question: What are the parasites that cannot be identified

by species by looking only at the egg?

stratum germinativum or stratum basale .

animal hookworms cannot penetrate the

route for human hookworms

stratum germinativum contains the blood vessels and this is used as a

penetrate the skin

enter the stratum basale, blood vessels

enter your systemic circulation

enter the heart and the lungs

route for human hookworms

stratum germinativum or the stratum basale

animal hookworms cannot penetrate the

under the epidermis

animal hookworms location

adults

animal hookworms aka larva migrans will never become __

LARVA MIGRANS ( ZOONOTIC HOOKWORMS )

Clinical features:

Ground itch to dry cough, wheezing ( 1-2 weeks later in primary infection

Abdominal discomfort

Progressive iron deficiency anemia

Failure to thrive

extreme fatigue IQ loss

40-150 worms associated with Hgb < 11 g / dL

Progressive iron deficiency anemia with larva migrans : # of worms associated with Hgb ___g / dL

Albendazole x 1 dose

LARVA MIGRANS Treatment

Filariform larva

- forked or knotched tail

STRONGYLOIDES STERCORALIS infective stage

STRONGYLOIDES STERCORALIS

Swollen belly or baby syndrome

May live as a free - living adult ( male and female )

- Found in the soil or in environment

Disseminated infections in immunocompromised ( deadly )

Facultative parasite

Females

STRONGYLOIDES STERCORALIS: Only___ are known to be parasitic

rhabditiform larva in stool

STRONGYLOIDES STERCORALIS Laboratory diagnosis : detection of

Strongyloides stercoralis

Length of the buccal capsule / cavity: short

Ancylostoma

Length of the buccal capsule / cavity: long