(M) Nematoda: Filarial Worms (Module-based)

Question 1

referred as blood and tissue-inhabiting nematodes, live in the tissues and/or body cavities of a vertebrate host including man

Answer 1

Filarial worms

Question 2

(male/female worm) larviparous and insect vectors are needed for transmission of the infection

Answer 2

Female worms

Question 3

The laid larvae are called?

Answer 3

microfilariae

Question 4

The time of the day whereby blood and other tissue fluids contains abundant number of microfilariae, as compared to other hours, is called

which is of great value in the timing of when to get clinical specimen to produce high yield of positive results

Answer 4

periodicity

Question 5

known to be an endosymbiont of filarial worms, including W. bancrofti, B. malayi and O. volvulus

Answer 5

Wolbachia bacteria

Question 6

This is sucked by the insect vector, pass through the gut’s wall and into the hemocele of the insect.

Answer 6

microfilariae

Question 7

What stage goes into some parts of the vector’s mouth or salivary glands.

Answer 7

3rd stage filiform larva (L3)

Question 8

causative agent of Bancroftian’s filariasis

Answer 8

Wuchereriabancrofti

Question 9

It is highly endemic in Amoean Ellice, Tokelau, and Fiji Islands.

Answer 9

Wuchereria bancrofti

Question 10

It is also found in Burma, India, Saudi Arabia, Mauritius, Egypt, West and East Africa, and Congo.

Answer 10

Wuchecheria bancrofti

Question 11

 Males: 40mm long x 0.1mm in diameter with sharply curved posterior.
 Females: 80-100mm x 0.24-0.30mm with vulva at cervical region, single
uterus, but all the remaining reproductive organs are paired.
 Microfilaria: 244-296um long x 7.5-10um in diameter, sheathed, with graceful curves, rounded anterior, pointed caudal part, smooth cuticle, and body
nuclei are equidistant and regularly distributed.

Answer 11

Wuchecheria bancrofti

Question 12

causes Malayan filariasis

Answer 12

BRUGIA MALAYI

Question 13

It is endemic in India, Sri Lanka, Sumatra, Java, Borneo, Celebes, Malaysia, the Philippines, Thailand, North Vietnam, China, South Korea, and Japan.

Answer 13

Brugia malayi

Question 14

causing Calabar or Fugitive swelling involves the eyes with microfilariae that exhibit diurnal periodicity

Answer 14

Loa loa

Question 15

Endemic in west and Central Africa, especially Nigeria, Cameroon, and Zaire, and vectors are species of tabanid flies of genus Chrysops.

Answer 15

Loa loa

Question 16

vectors of W. bancrofti & B. malayi

Answer 16

Mansonia
Aedes
Anopheles
Cules

Question 17

 Females measure 43-55mm long, 130-170um (diameter)
 Males 13-23mm long x 70-80um in breadth
 Microfilaria 177-230um, sheathed, with a kinky body, unevenly distributed
body nuclei, two prominent terminal nuclei which is diagnostic.

Answer 17

BRUGIA MALAYI

Question 18

Vectors of Loa loa

Answer 18

Sp. of tabanid flies of genus Chrysops

Question 19

Adult worm inhabiting subcutaneous tissues have a pair of lateral papillae and two pairs of sub-median papillae, all of which are sessile and are small. The skin has small bosses, which are not seen in males.

Answer 19

Loa loa

Question 20

 Male: measure 30-34 mm long by 0.35-0.43 mm in diameter
 Females: 40-70 mm by 0.5 mm
 Microfilaria: measures 250-300 x 6-8um with uneven distribution of body
nuclei that extend to the tip of the tail.

Answer 20

Loa loa

Question 21

producing onchocerciasis or river blindness, with microfilariae in lymphatic fluids and both adults and microfilariae may be found in the skin and subcutaneous tissues where they produce fibrous nodules.

Answer 21

Onchocerca volvulus

Question 22

Onchocerca volvulus commonly known as

Answer 22

Convoluted filaria

Question 23

Vectors of Onchocerca volvulus

Answer 23

Black flies of genus simulium

Question 24

Adult worms are white, opalescent, and transparent, with distinct transverse striations of the cuticle. Males are 19-24mm long x 130-210um in diameter. Females are 3.5-50mm x 270-400um in diameter. Microfilariae are 315-360um by 6um with both ends free of nuclei.

Answer 24

Onchocerca volvulus

Question 25

Onchocerca volvulus may be found in what specimens?

Answer 25

Urine, blood and sputum

Question 26

Onchocerca volvulus are commonly found in what areas/tissues of the body?

Answer 26

more commonly in the lymphatic of the connective tissues and cutaneous layers in an area around the adult worms in the corneal conjunctivae.

Question 27

with adults inhabiting in body cavities, producing non- periodic, unsheathed microfilariae

Answer 27

Mansonella ozzardi

Question 28

Mansonella ozzardi AKA

Answer 28

Ozzard's filaria

Question 29

They ca be found in Argentina, Bolivia, Brazil, Peru, Venezuela, Trinidad, Colombia, and Panama. Insect vectors are midges of genus Cullicoides.

Answer 29

MANSONELLA OZZARDI

Question 30

Adult male measures 24-28mm long by 70-80um diameter. Females are 65- 81mm long by 0.21-0.25mm diameter. The microfilariae measures 200um by 4.5um. The tail end is tapered like a filament, contains a column of four to six ovoid or bar-like body nuclei.

Answer 30

Mansonella ozzardi

Question 31

Mansonella perstans is also called

Answer 31

Dipetalonema perstans

Question 32

Adult worms inhabit the body cavities in man. It is non-periodic, and unsheathed microfilariae. They are native in in South America and Africa. Vectors are midges of genus Cullicoides.

Answer 32

Mansonella perstans

Question 33

Adult male measures 45mm long x 60um. Females are70-80mm long x 120um. Microfilariae measures 200um x 4.5. The body nuclei fill up entire body, with no distinct space at cephalic or tail end.

Answer 33

Mansonella perstans

Question 34

TOF. The microfilariae are the ones causing damage to humans and dependent on where the worm is located.

Answer 34

F (adult worms)

Question 35

Adult worms, in body cavities and subcutaneous tissues, produce what swelling?

Answer 35

nodular swelling

Question 36

Adult worms, in body cavities and subcutaneous tissues, produce nodular swelling such as those found in infections with?

Answer 36

Mansonella perstans

Question 37

Migrating adults of L .loa cause temporary migratory inflammation, thus the term?

Answer 37

Fugitive or calabar swelling

Question 38

Swelling in the eyes is also called

Answer 38

bug, bung, or bulge eye

Question 39

# Sp. usually produces little tissue reactions and are commonly not observed

Answer 39

Mansonella ozzardi

Question 40

This parasites are commonly located in lymphatic channels of the subcutaneous tissues in areas with bony prominence such as the scalp, scapula, ribs, elbow, iliac crests, sacrum, and knees.

Answer 40

Onchocerca volvulus

Question 41

oftentimes, located in lymphatic channels of the lower part of the body

Answer 41

Wuchecheria bancrofti & Brugia malayi

Question 42

This incite cellular reaction in lymph nodes and lymphatic channels.

Answer 42

ADULT WORMS

Question 43

These changes, running a gradual course, eventually lead to lymphatic obstruction causing impedance in the flow of lymph, which in chronic cases lead to?

Answer 43

Lymphedema (enlargament of the involved extremities)

Question 44

Enlarged lower extremities, due to lymphedema, assume the appearance of an elephant’s legs, hence the term?

Answer 44

Elephantiasis

Question 45

may cause lymphangitis, lymphadenitis, orchitis, epididymitis, funiculitis, elephantoid fever, secondary bacterial infection, dilatation of lymphatics with hypertrophy and hyperplasia, progressive obstruction of the lymphatic channels due to scar tissue formation ending with fibrosis, lymph blockade, and finally elephantiasis of the affected organ or limb.

Answer 45

Bancroft’s or Malayan filariasis

Question 46

periodic type is generally distributed throughout Asia

Answer 46

Nocturnal

Question 47

periodic type is found to be limited in some areas of Malaysia, Indonesia, and the Philippines (Bicol); has animal reservoir hosts, such as domestic cats, leaf monkeys, and other wild animals.

Answer 47

Nocturnal subperiodic

Question 48

# Bancroft's filariasis as main vector (urban type) and is found in almost the whole tropical and subtropical regions

Answer 48

Culex quinquifasciatus

Question 49

# Bancroft’s filariasis rural form serve as vectors and can be found in the Philippines.

Answer 49

Anopheles maculatus, A. flavirostris, and Aedes poicilus

Question 50

Manifestations of Bancroft’s filariasis are the same with those seen in Malayan filariasis, but W. bancrofti affects?

Answer 50

genital organs more than Brugia malayi

Question 51

Cases of hydrocele, orchitis, funiculo-epididymitis, chyluria are more commonly observed in what disease/parasite

Answer 51

Wuchercheria bancroft or bancroft's filariasis

Question 52

Lab diagnosis to demonstrate adult worms

Answer 52

Lymph node or tissue biopsy may be done, stained with Haematoxylin-Eosin method

Question 53

Laboratory Diagnosis of filaria worm infection is based on recovery of microfilariae in?

Answer 53

blood films or lymphatic fluids

Question 54

TOF. When most of the clinical signs/symptoms are prominent, it is the time when the microfilariae tend to be very few in the blood.

Answer 54

T

Question 55

TOF. During the sub-clinical period, the blood is oftentimes free of organisms.

Answer 55

T

Question 56

# Treatment both kill the microfilariae and adult worms is the drug of choice for lymphatic filariasis

Answer 56

Diethylcarbamazine citrate (DEC)

Question 57

# Treatment This medic. is effective against the microfilariae of W. bancrofti only, not the adult worm.

Answer 57

Ivermectin

Question 58

# Treatment Ivermectin is effective against the microfilariae of?

Answer 58

W. bancrofti only

Question 59

TOF. Ivermectin is effective against the adult worm of W. bancrofti only.

Answer 59

F (microfilaria)

Question 60

Control and Prevention

Answer 60

* Public education, especially those at risk of the infection, and early diagnosis and immediate treatment, which in turn control transmission to vectors will markedly reduce incidence of the infection * Use of insect repellants, mosquito nets, changing the nature of the mosquitoes’ breeding places will greatly lower the incidence of infection