PARA Midterms

Phasmid nematode

with caudal chemoreceptors

Ingestion of embryonated eggs

Ascaris

Trichuris

Enterobius

Ingestion of infected larva

capillaria

trichinella

angiostrongylus

ingestion of encysted larva in muscle

trichinella

skin penetration of L3 (filariform larvae)

Hookworms

Strongyloides

Vector-borne

Wuchureria

Brugia

Autoinfection

strongyloides

enterobius

inhalation

ascaris

enterobius

small intestine

ascaris lumbricoides

ancylostoma duodenale

necator americanus

strongyloides stercoralis

trichinella spiralis

capillaria philippinensis

large intestine

trichuris trichuria

enterobius vermicularis

lymphatics

wuchereria bancrofti

brugia malayi

brugia timori

skin or subcutaneous tissue

loa loa

onchocerca volvulus

dracunculus medinensis 

mansonella streptocerca

mesentery/serous cavity

mansonella ozzardi

mansonella perstans

conjuctiva

loa loa

filarial worms mode of transmission

bite of blood sucking insects/mosquito

filarial female worms reproduction 

viviparous = give birth to larvae (microfilariae)

Location of filarial worms when not in circulation

capillaries/blood vessels in the lungs

Nocturnal periodicity

largest number in blood at night

wuchureria bancrofti

diurnal periodicity

largest number of microfilariae in blood during the day

loa loa

nonperiodic

constant levels during day and night

onchocerca volvulus

subperiodic or nocturnallu subperiodic

can be detected throughout the day but higher in late afternoon or at night

brugia malayi

sheathed microfilaria

wuchureria bancrofti

brugia malayi

loa loa

unsheathed microfilaria

onchocerca volvulus

mansonella perstans

mansonella ozzardi

vector of brugia malayi

mansonia spp (mansonia bonnae & mansonia uniformis

vector of wuchereria bancrofti

aedes

culex

anopheles

infective stage of lymphatic filarial parasites (wuchereria bancrofti and brugia malayi)

to man: L3 larva or filariform 

to vector: microfilariae

diagnostic stage of lymphatic filarial parasites

microfilariae

definitive host of lymphatic filarial parasites

man

common name of wuchureria bancrofti

bancroft’s filarial worm

common name of brugia malayi

malayan filarial worm

affected area of wuchureria bancrofti

lowe lymphatics

affected area of brugia malayi

upper lymphatics

periodicity of wuchureria bancrofti

nocturnal

periodicity of brugia malayi

subperiodic

aedes poecillus

breed in water

accumulation in abaca and banana plant 

aquatic habitat

axils of abaca and banana plant

adult biting

day and night

indoor and outdoor

adult resting

base of abaca plant (cool shady area)

molting

L1 to L3

target site of wuchureria bancrofti

lymphatic tissues

intermediate host of brugia malayi

mansonia spp

classic filariasis

blockage due to allergic reaction to worm

why lymph nodes

favorable to parasite; less aggressive, no plts, complement, granulocytes, less violent flow

infiltration

macrophages, eosinophils, lymphocytes, plasma cells

lymph statis and dilation of lymph vessels

thicken vessel wall

narrow lumen

granuloma formation

subsequent scarring and calcification

hard pitting/ brawny edema/ filariasis

increased lymph vessel permeability = leakage of protein-rich lymph into tissue

acute filarial disease

adenolymphagitis (ADL) / dermatolymphangiodenitis (DLA)

onset high grade fever with rigors 2-3 days

lymphatic inflammation

transient local edema

epididymo-orchitis and funiculitis

lymphadenitis

inflammation of lymph node (inguinal nodes and axillary nodes)

painful and tender lymph nodes

lymphangitis

inflammation of lymphatic vessels, manifests as red streaks in the skin

associated with streptococcal infection

Chronic filarial disease

more common

lymphedema

lymphoangiovarix

lymphangitis and lymphadenitis (more in wuchureria bancrofit)

lymphedema 

successive attacks of lymphangitis 

swelling ankle to back of foot and leg

originally pitting, eventually becomes hard and non pitting

pitting in nature

swollen part looks like dimple after pressing

lymphoangiovarix

dilation of lymph vessels (inguinal, scrotal, testicular, abdominal sites)

elephantiasis

delayed sequel to repeated lymphangitis

non pitting brawny edema

lower limbs commonly affected 

possible accumulate bacterial infection

hydrocoele

accumulation of fluid due to obstruction of lymph vessels of spermatic cord

exudation of inflamed testes and epididymis

fluid in hydrocoele

clear and straw colored but may be cloudy, milky, or hemorrhagic

manifestations of chronic bancroftian filiaris

chronic epididymitis, funiculitis, lymphedematous, thickening of spermatic cord

lymphorrhagia

chylocele, milky appearance

release of lymph or chyle = chyluria (milky urine), chylous diarrhea, chylous ascites, chycothorax

expetriate syndrome

occurs to migrants infected from endemic regions

hyperresponsiveness to matured/maturing worms

acute manifestations: hives, rashes, blood eosinophilia

occult filariasis 

absent clinical manifestations (hidden)

hypersensitivity reaction to microfilarial antigens 

microfilariae not found in blood = destroyed by tissues

other names of occult filariasis

weingartner’s syndrome

meyer’s-kouwenaar syndrome

pseudo-tuberculosis of lung

eosinophilic pseudo-leukemia

tropical eosinophilic asthma

frimodt-moller and barton syndrome

clinical manifestations of occult filariasis

massive eosinophilia (30-80%)

hepatosplenomegaly

pulmonary symptoms (dry nosturnal cough, dyspnea, asthmathis wheezing)

cause arthritis, glomerulonephritis, thrombophlebitis, tenosynovitis

tropical pulmonary eosinophilia

low grade fever, loss of weight, pulmonary symptoms

increase eosinophil count

mottled shadows chest x-ray similar to miliary tuberculosis

high IgE serum level and filarial antibodies

affected by tropical pulmonary eosinophilia

children and young adults

indian subcontinent

treatment of tropical pulmonary eosinophilia

diethylcarbamazine

stage 1 chronic lymphedema

swelling increases during day but reversible when px lies flat in bed

stage 2 chronic lymphedema

irreversible swelling

stage 3 chronic lymphedema

shallow skinfolds

stage 4 chronic lymphedema

knobs, lumps, protrusions

stage 5 chronic lymphedema

deep skinfolds

stage 6 chronic lymphedema

mossy lesions with leaking transluscent fluid

stage 7 chronic lymphedema

foul-smelling infected area, px unable to perform daily activities

wet smears

demonstrate motile microfilariae

thick blood smears

giemsa stain: demonstrate microfilariae

most practical diagnostic procedure

differences in microfilariae:

mean length

w. bancrofti - 290

b. malayi - 222

differences in microfilariae:

cephalic space/breadth

w. bancrofti - 1:1

b. malayi - 2:1

differences in microfilariae:

sheath affinity to giemsa

w. bancrofti - unstained

b. malayi - pink

differences in microfilariae:

body nuclei

w. bancrofti - regulaly spaced

b. malayi - irregular & overlapping

differences in microfilariae:

terminal nuclei

w. bancrofti - none

b. malayi - 2 nuclei

differences in microfilariae:

appearance in blood film

w. bancrofti - smooth, gracely curved

b. malayi - kinky

knott’s concentration technique

anticoagulated blood 1ml: 2% formalin 9ml

centrifuged 500g 1 min

wright/giemsa stain

nucleopore filtration

5ml blood filtered through millipore or nucleopore membranes (3um diameter)

dec provocation test

small dose diethylcarbamazine induces microfilariae

provokes microfilariae to appear in the blood

other specimens

microfilariae in centrifuged deposits of lymph, hydrocele fluid, chylous urine, etc

ultrasonography

high frequency ultrasonography of scrotum and female breast

with doppler imaging

identification of motile adult worm (filaria dance sign) within dilated lymphatics

radiology

dead and calcified worms detected by xray

tropical pulmonary eosinophilia (TPE) mottled appearance resembling miliary tuberculosis chest xray

antibody demonstration

complement fixation, indirect hemagglutination, indirect fluorescent antibody, immunodiffusion, and immunoenzyme

demonstration of circulating antigen

highly sensitive and specific test

detect circulating filarial antigen recent bancroftian filariasis

molecular diagnostic technique for filarial worms

PCR detect filarial DNA from px blood if present in peripheral blood but not in chronic carrier state

loa loa common name

african eye worm

loa loa vector

chrysops spp.

deerflies

mango flies

mangrove flies

tabanid flies

horse flies

loa loa area affected

subcutaneous tissue

loa loa periodicity

diurnal

loa loa mode of transmission

skin penetration of vectors

intermediate host of loa loa

chrypsos

pathology of loa loa

loaisis, fugitive swellings, calabar swellings

localized subcutaneous edema as the microfilariae die in caapillaries around the eye

treatment loa loa

diethylcarbamazine or ivermectin

immobilize loa loa parasite

few drops of 10% cocaine and extract worm in the eyes

unsheathed microfilariae onchocerca volvulus other names

convulated filaria,

binding filaria,

gale filarienne, 

craw craw