non-diarrheal invasive infestations

Question 1

Ascaris lumbricoides

size

Answer 1

giant intestinal roundworm, “the wanderer”

adult female: 30 cm long, 5mm diameter
male: shorter, narrower, curved posterior with pair of copulatory spicules -yikes!

Question 2

Ascaris adults live in the ?? where they do not ?? but rather ??

Answer 2

small intestine

don’t hatch, but constantly move agains peristalsis

Question 3

Ascaris female produces how many eggs/day

eggs are ??? until they are deposited in soil with poop

embryonization can take place in ?? or longer if unfav. conditions

Answer 3

200,000 eggs/day

fertilized, not embryonated

2-4 wks

Question 4

when ingested, Ascaris larvae hatch in the ?? penetrate the ??and are carried via blood to ??

Answer 4

small intestine

lamina propria, carried to the liver, heart, then lungs

Question 5

in the lungs, Ascaris larvae lodge in the ?? and break out into the ??

from there the larvae actively migrate ???

Answer 5

alveolar capillaries
alveolar spaces

up the bronchi into the trachea, across the epiglottis
are SWALLOWED, reaching the lumen of the small intestine

Question 6

Ascaris lumbricoides larvae do what in the small intestine

Answer 6

grow and reach sexual maturity

cycle then begins again

Question 7

whole Ascaris cycle takes ??

how long to the worms live ??

Answer 7

2-3 mos

1-2 yrs

Question 8

Ascaris occurs where ??

host/reservoir?

Answer 8

S and SE US (need warm embryonation in soil)
humans are sole host/reservoir, 1-4 mill affected

Africa, Latin America, East Asia

Question 9

light Ascaris infections are

Answer 9

asymptomatic (typ. of parasites: host-parasite homeostasis)

Question 10

most intense reactions with Ascaris are caused by ??

what type of reaction occurs ??

Answer 10

migrating larvae, esp. if high numbers

Type 1 hypersensitivity rxn: cough, wheezing, urticaria, fever

Question 11

other complications of Ascaris larvae migration

Answer 11

hepatic damage
lung damage, vermis pneumonitis
other organs

Question 12

if moderately infected with Ascaris adult worms…

Answer 12

rarely symptomatic

vague abd pain, acute colicky pain (heavier infections)

Question 13

Ascaris aka “the wanderer” may pass spontaneously via

Answer 13

vomiting, thru nares when adult worms wander up there

Question 14

young kids with large Ascaris burden may ??

Answer 14

be malnourished or have nutr. deficiencies, stunted growth

Question 15

Ascaris adult worm infection complications

Answer 15

bolus obstruction
perforation of intestine
blockage of bile duct
-others related to aberrant adult migration

Question 16

this may irritate Ascaris adult worm and cause migration

Answer 16

tx for other nematode infections

Question 17

dx Ascaris

Answer 17

migrating larvae, vermis pneumonitis
hx, CXR
eosinophilia, Charcot-Leyden crystals NO anemia
worms in stool, other sites
ova in stool (easily found due to so many produced)

Question 18

Ascaris tx

Answer 18

mebendazole
pyrantel pamoate
good ppx

Question 19

how to prevent Ascaris

Answer 19

sanitary disposal of feces
educating at risk pop
washing raw fruit/veggies in clean water

Question 20

this 2 hookworms are very similar

but differ in ??

Answer 20

Necator americanus
Strongyloides stercoralis

different geography

Question 21

Necator americanus

crazy estimate !!

Answer 21

New World hookworm
-tropical and subtropical regions of Africa, Asia, Central and South America
-US: S/SE (2-15% prevalence)
estimated 1/6th of world infected!

Question 22

Ancylostoma duodenal

Answer 22

Old World hookworm

distribution overlaps Necator americanus

Question 23

N. americanus morphology

Answer 23

female adults: 1 cm, males a bit shorter
buccal cavity has 2 cutting plates

ova: thin-shelled, early cleavage stage found in feces
larvae: Rhabditiform (non-inf) and Filariform (infective)

Question 24

N. americanus adults live in ?? where the feed on ??

Answer 24

the small intestine, feed on the intestinal villi by their cutting plates (Necator) or teeth (Ancylostoma)

Question 25

N. american eggs are embryonated ?? after pooped out and deposited in soil the ?? will hatch w.in 48 hrs of deposition and will grow/dev. in soil into ??

Answer 25

immediately rhabditiform larvae filariform larvae

Question 26

the N. american filariform larvae will seek out ?? in order to ?? then ??

Answer 26

a tall blade of grass, etc. to contact human skin then actively penetrate subcutaneous tissue (hair follicle) and carried via blood

Question 27

N. american filariform larvae are carried via blood to ?? where they ?? similar to ???

Answer 27

lungs break out of alveolar capillaries, cruel up bronchi and trachea over the epiglottis and into pharynx and swallowed Ascaris "the wanderer"

Question 28

N. american larvae develop into adult worm in the ??

Answer 28

small intestine

Question 29

N. americanus symps caused by ?? | manifestations ?

Answer 29

penetration of larvae ground or dew itch (allergic reaction): intense itching, burning erythema, edema, papular lesions-->vesicular if sensitized

Question 30

N. american symps not typically caused by ?? | unless ??

Answer 30

larval migration thru lung (inapparent) | unless heavy worm infestation-->vermis pneumonitis

Question 31

N. american sypms from adults in sm. intestine depends on ?? and ??

Answer 31

loss of blood ``` worm burden (need 200+) host nutritional status (related to host Fe++ loss and replacement) ```

Question 32

light N. american infection typically

Answer 32

no recog. symptoms

Question 33

acute/heavy N. american infection

Answer 33

heartburn, flatulence, diarrhea, wl, +/- eosinophilia | GI symps disappear if become chronic

Question 34

chronic N. american infection resembles ?? bad symps in kiddos?

Answer 34

iron deficiency anemia fatigue, ha, numbness, tingling, dyspnea, anorexia, hd/ft edema, sexual dysfunction, pallor, tachy, enlarged heart physical, mental dev. may be arrested

Question 35

N. armerican dx

Answer 35

clinical suspicion + labs: ova in feces, quant. counts for worm burden, CBC looks like infection/iron deficiency (hypochromic RBC, eosinophilia)

Question 36

N. american tx

Answer 36

Mebendazole

Question 37

N. american prevention

Answer 37

``` improve sanitary facilities, only poop in toilets! don't use night soil wear shoes education mass tx ```

Question 38

Strongyloides stercoralis

Answer 38

roundworm occurs in warms climates like hookworms (N. americanus) also spread sporadically in temperate climates

Question 39

signif reservoir of Strong ster

Answer 39

dogs

Question 40

Strong ster has both a ??

Answer 40

free living phase and parasitic cycle

Question 41

Strong free-living phase: larvae are ?? | form of larvae ?? will ??

Answer 41

pooped out and deposited in soil (unlike hookworms) | rhabditiform larvae will grow and dev. into free-living adult worms

Question 42

Strong free-living phase is

Answer 42

diecious, adults mate and female produces embryonated eggs that hatch and undergo similar cycle

Question 43

if poor conditions, the Strong filariform larvae will ??

Answer 43

penetrate skin of host and begin parasitic infection

Question 44

initial part of Strong parasitic life cycle:

Answer 44

similar to hookworms and Ascaris (spread to lungs, swallowed) larvae develop into *female* adults in small intestine

Question 45

Strong female adult is ?? and can live ?? weird brief appearance of ??

Answer 45

2 mm (small), lives w.in and among columnar epi cells of sm. intestine male sex organs-->self-fertilization-->involution of male gonads *no parasitic male per se*

Question 46

Strong embryonated eggs hatch in ?? and proceed to ?? | where they develop to ?? and are ??

Answer 46

sm. intestine-->colon | rhabditiform larvae, pooped into soil

Question 47

if host is constipated, Strong rhabditiform larvae will ??

Answer 47

develop into filariform larvae and directly re-infect host by penetrating colon mucosa or perianal area

Question 48

Strong ster: common? | found where ??

Answer 48

``` less prevalent than hookworm SE USA, rural areas (0.4-4%) mental institutions (40%) veterans immunocompromised pts ```

Question 49

Strong ster symptoms due to penetration

Answer 49

little reaction observed in direct cycle, if auto infected may see creeping eruption at perianal region

Question 50

Strong ster sypms from larval migration thru lungs..

Answer 50

few unless large infestation: pneumonitis, peripheral eosinophilia

Question 51

Strong intestinal symps

Answer 51

invasion of mucosa, enteritis, tissue damage

Question 52

manifestation of Strong ster infection

Answer 52

most asymptomatic moderate: pain in epigastric region, diarrhea w. alternating constipation eosinophilia severe: malabsorption

Question 53

autoinfections of Strong ster may lead to

Answer 53

sev. systemic infections, gen. abd pain, shock, fever, G- sepsis

Question 54

Strong steer may cause ?? in immunocompromised host

Answer 54

hyperinfection

Question 55

Strong ster dx

Answer 55

most difficult roundworm to dx eosinophilia in 50-80% look for larvae in feces (vs. ova in feces for hookworm) serum IgG by ELISA skin tests larvae in sputum: agar test, look for worm tracks

Question 56

Strong ster tx

Answer 56

Thiabendazole

Question 57

Strong ster prevention

Answer 57

``` same as hookworm: improve sanitary facilities, only poop in toilets! don't use night soil wear shoes education mass tx ```

Question 58

Visceral and cutaneous larval migrans

Answer 58

"lost worms" cut/subcut condition from skin penetration and transient migration of hookworm larvae form dogs, cats, etc larvae die once in human host, but penetration/migration causes a "creeping eruption" inflamm. response in skin -irritating and can become scratched and secondarily infected