helminths

Question 1

Many helminths undergo part of their life cycle

Answer 1

outside of the human host

Question 2

Helminths:

Some are transmitted only from ______
Others are capable of _____ (e.g. strongyloidiasis)

Answer 2

Some are transmitted only from human to human (e.g. enterobiasis)
Others are capable of auto-infection (e.g. strongyloidiasis)

Question 3

• Found predominantly in fecally contaminated soil
• Transmitted by fecal-oral route or by direct penetration of the skin
• Many species infect children in developing countries, leading to malnutrition, growth retardation and cognitive deficits

Answer 3

nematodes- round worms

Question 4

Ascariasis: Clinical Presentation

(mos)often asymptomatic unless obstruction or perforation due to large burden of worms; can cause malnutrition

Answer 4

Intestinal phase:

Question 5

Ascariasis: Clinical Presentation

(mos-yrs)migrate into biliary tree causing cholangitis, cholecystitis, hepatic abscesses

Answer 5

Hepato-biliary phase:

Question 6

Ascariasis: Clinical Presentation

wks-mos) hypersensitivity pneumonitis (Loeffler’s

Answer 6

Migratory phase:

Question 7

ascariasis diagnosis and treatment

Answer 7

diagnosis is through the passage of eggs or worms and albendazole as the treatment

Question 8

Human disease only: passed from human to human (usually via children)
Very common in cosmopolitan areas in temperate climates
Eggs laid in perirectal area, child scratches area then sucks thumb or contaminates food with the eggs
Eggs hatch in ileum, worm migrates to anus to lay eggs
Causes pruritis ani, perianal eczema; insomnia

Answer 8

pinworm

Question 9

pinworm treatment

Answer 9

treat the whole family. use albendazole

Question 10

stronglyloides difference to other helminths in the infection phase?

what could we see?

what develops in the setting of immunosuppression?

Answer 10

they hatch inside you and leads to autoinfection

• what could we see?–>we see mild eosinophilia
• what develops in the setting of immunosuppression?–> hyperinfection

Question 11

treatment of strongyloides

Answer 11

ivermectin

Question 12

Complex developmental cycles involving snails and humans or other mammals

Can be acquired by ingestion or by penetration of intact skin

Host tissue is ingested via suckers

Answer 12

trematodes- flatworms

Question 13

Infection is acquired through the skin while bathing in fresh water
Similar life cycles and acute disease; chronic disease and long term consequences are different for each species but it is the eggs that cause the issue

Answer 13

trematodes- schistosoma

Question 14

Schistosomiasis: clinical manifestations

(hours) pruritic papular rash after swimming, “swimmer’s itch”

Answer 14

Cercarial dermatitis:

Question 15

Schistosomiasis: clinical manifestations

(1-2 mos) fever, chills, headache, LAD, HSM, eosinophlia; due to adults releasing eggs into tissues

Answer 15

Acute schistosomiasis (Katayama fever):

Question 16

pipe stem fibrosis

Answer 16

it is the chronic disease we see with shictosomiasis and it is due to the repeated exposure/infection reaction to eggs

this occurs in the liver

Question 17

dults migrate through portal system; eggs migrate through intestinal wall, embed in it or are swept back into portal system
Causes blood in the stool; pipe stem (periportal) fibrosis; portal HTN

Answer 17

S.masoni

Question 18

Mao’s troops unable to launch amphibious assault on Taiwan due the development of Katayama fever while encamped on the Yangtze river
Similar to Mansoni
Worst of the 3, largest numbers of eggs with extensive granulomas

Answer 18

S. japonicum

Question 19

Ancient Egyptians believed manhood was heralded by blood in the urine
Eggs laid in venous plexus of bladder, migrate through bladder wall or embed
Causes hematuria, recurrent UTIs; increased risk of squamous cell carcinoma of the bladder

Answer 19

S. Hematobium

Question 20

what type of cancer do we see in shistosomiasis

Answer 20

bladder cancer

Question 21

diagnosis of shistosomiasis and treatment

Answer 21

serology and treatment is praziquantel

Question 22

Flat segmented worms composed of a head (scolex) and a series of segments (proglottids)
They absorb nutrients from the host’s gut through their tegument
Adult ones usually do not cause significant pathology in the human intestine
But when humans serve as intermediate hosts they can cause significant morbidity

Answer 22

cestodes: tapeworms

Question 23

tapeworm transmission

Answer 23

poorly cooked pork

Question 24

taeniasis

Answer 24

same as tapeworm but in beef

Question 25

taeniasis treatment

Answer 25

praziquantel

Question 26

Cysticercosis

Answer 26

it is when we eat the eggs of the tapeworm and it migrates to the muscles, brain and eyes

Question 27

diagnosis of Cysticercosis and treatment

Answer 27

CT/MRI and albendazole. steroids and antiseizure (if brain spread)

Question 28

Echinococcus: Hydatid Disease

Answer 28

dog tapeworm

Question 29

Echinococcus: clinical presentation

Answer 29

liver (65%) and lung (25%) affected with cysts growing and evading immune response over the years

Question 30

hydated diagnosis and treatment

Answer 30

imaging
for hepatic cysts- PAIR
for multiple cysts- surgical

+ albendazole

Question 31

anti-parasite drugs MOA

Answer 31

act by paralyzing worms