Lec 08 Filariasis

Question 1

Filariasis is endemic in what regions?

Answer 1

tropical and sub-tropical regions

Question 2

True of filarial worms

A. nematodes or roundworms
B. live in the lymphatics
C. transmitted by mosquito
D. infective stage found in the mosquito
E. B & C only
F. AOTA

Answer 2

F. AOTA

Question 3

What is the infective stage of filariasis?

Answer 3

L3 (third-stage filarial larva)

Question 4

Enumerate the mosquito vectors of Wuchereria bancrofti.

Answer 4

Aedes
Anopheles
Culex

Question 5

Enumerate the mosquito vectors of Brugia malayi.

Answer 5

Mansonia

Aedes

Question 6

When is the best time to collect blood in a suspected filariasis patient?

A. morning
B. noon
C. evening
D. anytime

Answer 6

C. evening

nocturnal periodicity - release of microfilaria into the peripheral blood occurs at night

Question 7

T/F: Microfilaria develops into the L1 (first-stage larva) in the human host.

Answer 7

F. They must be ingested by the mosquito vector to proceed to the larval stage.

Question 8

What is the diagnostic stage of filarial worms?

Answer 8

microfilariae

Question 9

True of Wuchereria bancrofti

A. smaller
B. 2:1 cephalic length:breadth ratio
C. 2 terminal nuclei
D. gently curved body
E. sheath pink

Answer 9

D. gently curved body

other choices are for Brugia malayi

Question 10

Features of acute filariasis EXCEPT

A. dermatolymphangioadenitis
B. vomiting
C. fever
D. hydrocoele formation

Answer 10

D.

hydrocoele is a feature of CHRONIC filariasis

Question 11

T/F: Worm may be dead in chronic filariasis.

Answer 11

T

Question 12

The damage caused by adult worms is due to

Answer 12

obstruction of lymphatic drainage

Question 13

T/F: Diagnosis is hinged on the isolation of adult worms.

Answer 13

F

You may introduce bacteria when doing biopsy in fibrotic / swollen tissues.

Do smear for microfilaria instead.

Question 14

This has higher sensitivity.

A. thick blood smear
B. thin blood smear
C. kato katz smear
D. kato thick smear

Answer 14

A. thick blood smear

thin is for morphology and identification

yung kato smears ay para sa tae

Question 15

What is the size of the nucleopore to be used in filtration?

Answer 15

5 micrometer

Question 16

What is detected in the WB rapid and panLF rapid diagnostic test for filariasis?

Answer 16

IgG4

Question 17

This can be seen upon ultrasound of hydrocoele / swollen scrotum.

Answer 17

dancing filaria / dance sign

Question 18

Initial infection is dominated by

A. Th2
B. Th1
C. both
D. Th17

Answer 18

A. Th2

inflammatory phase = Th1
obstructive phase = both

Question 19

The Th1 response against filaria is mediated by?

Answer 19

IFN-gamma

Question 20

T/F: There is granuloma formation in chronic filariasis.

Answer 20

T

Question 21

This drug is used for mass treatment of filarisis.

Answer 21

diethylcarbamazine (DEC)

Question 22

Another anti-filarial drug not available in PH.

Answer 22

ivermectin

Question 23

DEC is active against

A. microfilaria
B. adult worms
C. both
D. none, it’s for L2 larva

Answer 23

C. both

Question 24

Why can’t doxycycline be a suitable replacement for DEC + albendazole?

Answer 24

long treatment (4-8 weeks)
side effects (photosensitivity)
cannot be used in children

Question 25

But why is doxycycline used in the treatment of filariasis?

Answer 25

to kill Wolbachia, an obligatory symbiote inside filarial worms