3.5 - HUMAN HOOKWORMS AND STRONGYLOIDES Flashcards
(64 cards)
1
Q
- blood sucking nematodes causing anemia
- attaches to the intestinal mucosa
- soil-transmitted helminthes
A
human hookworms
2
Q
Ancylostoma duodenale
A
old world hookworm
3
Q
Necator americanus
A
new world hookworm
4
Q
host
A
man
5
Q
habitat
A
small intestine
6
Q
MOT
A
skin penetration
7
Q
infective stage
A
L3-Filariform
8
Q
diagnostic stage
A
egg
9
Q
- 56-60 um in length by 36-40 um wide
- Bluntly round ends
- Single thin transparent hyaline shell
- 2-8 cell stage of division
A
eggs
10
Q
Hookworm eggs are most commonly described as
A
thin shelled eggs
11
Q
young larva
A
Rhabditiform
12
Q
- larger than the threadworm (strongyloides)
- more attenuated posteriorly
- longer buccal cavity
- genital primordium is smaller
A
rhabditiform larvae
13
Q
Eggs of strongyloides and hookworms are very much similar, and the way for differentatiting them is by looking at their
A
rhabditiform and filariform
14
Q
infective larval stage
A
filariform
15
Q
- conspicuous - very visible, obvious
- inconspicuous - not visible, not obvious
A
filariform larvae (L3)
16
Q
buccal spears are conspicuous and parallel throughout their lengths
A
Necator americanus
17
Q
buccal spears are inconspicuous and traverse striations on the sheath in the tail region
A
Ancylostoma duodenale
18
Q
- male - broad caudal bursa, rib like rays
- mouths have semilunar cutting plates
- Small cylindrical fusiform grayish-white nematodes
- Head is curved opposite to the curvature of the body
- They look like s-shaped worms
- Spicules are fused
- Female: darkly stained (bigger)
A
Necator americanus
19
Q
- 5-9mm by 0.3 mm
- broad membranous caudal bursa with rib-like rays
A
male N. americanus
20
Q
9 to 11mm by 0.35 mm
A
female N. americanus
21
Q
- Slightly larger
- Head continues in the same direction as the curvature of the body
- Mouths: 2 pairs of teeth
- Spicules are split (separated)
A
Ancylostoma duodenale
22
Q
smaller sized hookworm
A
N. americanus
23
Q
larger sized hookworm
A
A. duodenale
24
Q
s-shaped
A
N. americanus
25
c-shaped
A. duodenale
26
semilunar cutting plate
N. americanus
27
2 pairs of teeth
A. duodenale
28
bipartite (2 digits)
N. americanus
29
Tripartite (3 digits)
A. duodenale
30
long, fused and barbed spicule
N. americanus
30
simple and barbed spicule
A. duodenale
31
life span of N. americanus
14 years
32
life span of A. duodenale
1 year
33
more prevalent in the PH
N. americanus
34
blood loss from N. americanus
0.03 mL/day
35
blood loss from A. duodenale
0.15-0.25mL/day
36
MOT of N. americanus
percutaneous
37
MOT of A. duodenale
Percutaneous and oral route
38
life cycle
1. eggs will shed in the soil
2. rhabditiform larva
3. filariform larva
4. skin penetration
5. lungs
6. trachea
7. cough
8. swallow
9. small intestine - final habitat
10. copulate
11. stool formation
12. contact with soil
39
A. duodenale is also capable of infection causing ?, besides skin penetration
ingestion of larvae or larval ingestion
40
Ancylostoma spp. larvae can become developmentally arrested and dormant in tissues. Re-activated larvae may ?.
enter the small intestine
41
egg hatches after
1-2 days
42
development of rhabditiform to filariform
7-10 days
43
- skin at the entry of the site
- lungs
- small intestine
- iron-deficient type anemia / microcytic hypochromic anemia
- hypoalbuminemia
pathogenesis and clinical manifestations
44
Skin at the site of entry (Cutaneous)
o Ground Itch (Dew itch)
o Miner's Disease
45
Lungs (Pulmonary)
o Bronchitis or pneumonitis (Wakana disease)
o Löffler's syndrome - may also be observed
46
Small Intestine (Intestinal)
o Abdominal pain
o Steatorrhea - stool samples with too much fat
47
stool samples with too much fat
Steatorrhea
48
- DFS
- kato thick/katz
- concentration test
- harada mori
diagnosis
49
disadvantage of kato thick/katz
rapid clearance of hookworm eggs after 30-60 minutes
50
Recommended for species identification
Harada Mori
51
harada mori: sediments
hookworm larva
52
harada mori: upper end of the filter paper
S. stercoralis
53
Philippine setting
Necator > Ancylostoma
54
factors for transmission
- defecation in soil
- not wearing of shoes
- environmental factors
55
paratenic hosts
rabbit, lambs, calves, pigs
56
additional MOTs for Ancylostoma
ingestion, transmammary, transplacental
57
treatment
- albendazole
- iron supplement (ferrous sulfate)
58
o CN: Cat Hookworm
o Buccal cavity: 2 pairs of teeth
Ancylostoma braziliense
59
o CN: Dog Hookworm
o Buccal cavity: 3 pairs of teeth
Anyclostoma caninum
60
o If we get infected by Ancylostoma braziliense and Anyclostoma caninum
o The worms will be trapped under your skin or stuck in the subcutaneous tissues
Creeping Eruption (CLM)
Cutaneous Larva Migrans
61
Animal hookworms will not be able to complete their life cycle if they infect ? instead of cats and dogs
humans
62
associated eosinophilic enteritis
A. caninum
63
- mistaken as A. braziliense
- observed from civet cat
- hookworms of cats and dogs in Asia
- second most common hookworm infecting humans
Ancylostoma ceylanicum
