Nematodes Part 2 Flashcards
1
Q
Thelazia californensis definitive host/location
A
dogs, cats, sheep, deer, humans; conjunctiva and tear ducts
2
Q
Thelazia californensis intermediate host
A
Face fly
3
Q
Thelazia californensis infective stage
A
L3 deposited by face fly when feeding around the eye
4
Q
Thelazia californensis clinical signs
A
Conjunctivitis, photophobia, excessive tearing
5
Q
Thelazia californensis diagnosis
A
Observe parasites in eyes, L1 may be present in tears
6
Q
Thelazia californensis treatment
A
Manual removal of parasites, ivermectin, control flies
7
Q
Scientific name of giant kidney worm
A
Dioctophyme renale
8
Q
Dioctophyme renale definitive host/location
A
Mink is the main host, also dogs, wolves, foxes, rarely cats, humans, pigs, cattle; kidney
9
Q
Dioctophyme renale intermediate host
A
annelid (lives on surface of crayfish)
10
Q
Dioctophyme renale paratenic host
A
fish, frogs
11
Q
Dioctophyme renale infective stage
A
L3 encysted in IH or paratenic host
12
Q
Dioctophyme renale prepatent period
A
5 mo - 2 yr
13
Q
Dioctophyme renale clinical signs
A
Usually right kidney only, blocked ureter, peritonitis, renal failure
14
Q
Dioctophyme renale diagnosis
A
Urine, adults
15
Q
Dioctophyme renale treatment
A
Remove kidney, remove adults
16
Q
Pearsonema plica definitive host/location
A
dogs, wolves, foxes; urinary bladder, pelvis of kidney
17
Q
Pearsonema feliscati definitive host/location
A
cats; urinary bladder, pelvis of kidney
18
Q
Pearsonema spp. paratentic host
A
Earthworm
19
Q
Pearsonema spp. infective stage
A
L1 in earthworm
20
Q
Pearsonema spp. prepatent period
A
2 mo
21
Q
Pearsonema spp. clinical signs
A
Cysitis, irritation of bladder mucosa, usually asymptomatic
22
Q
Pearsonema spp. diagnosis
A
Urine
23
Q
Pearsonema spp. treatment
A
Fenbendazole, ivermectin, may need to re-treat
24
Q
Eucoleus aerophilus definitive host/location
A
dogs, cats, foxes; respiratory tract
25
Eucoleus boehmi definitive host/location
dogs, foxes; paranasal sinuses, nasal cavity
26
Eucoleus spp. infective stage
Direct lifecycle, L2 in eggs
27
Eucoleus spp. prepatent period
40 days
28
Eucoleus spp. clinical signs
Coughing
29
Eucoleus spp. diagnosis
Fecal exam
30
Eucoleus spp. treatment
Fenbendazole, ivermectin
31
Filaroides hirthi definitive host/location
dogs, coyotes; lung parenchyma
32
Filaroides osleri definitive host/location
dogs, coyotes; nodules at bifurcation of trachea
33
Filaroides spp. infective stage
Direct lifecycle, L1 in feces, saliva, or respiratory secretions
34
Filaroides hirthi prepatent period
5 weeks
35
Filaroides osleri prepatent period
6-7 months
36
Filaroides spp. diagnosis
Fecal floatation, Baermann, radiography, endoscopy
37
Filaroides spp. treatment
Fenbendazole, ivermectin, remove nodules
38
Aelurostrongylus abstrusus definitive host/location
cats; lung parenchyma
39
Aelurostrongylus abstrusus intermediate host
land snails, slugs
40
Aelurostrongylus abstrusus paratenic host
rodents, birds, amphibians, reptiles
41
Aelurostrongylus abstrusus infective stage
L3 in IH or paratenic host
42
Aelurostrongylus abstrusus prepatent period
4-6 weeks
43
Aelurostrongylus abstrusus clinical signs
Coughing, nodules on lung surface
44
Aelurostrongylus abstrusus diagnosis
Fecal exam (L1), radiography
45
Aelurostrongylus abstrusus treatment
Fenbendazole, moxidectin, ivermectin?
46
Angiostrongylus cantonensis definitive host/location
rats; heart, pulmonary arteries
47
Angiostrongylus cantonensis intermediate host
snails, slug
48
Angiostrongylus cantonensis incidental hosts
dogs, humans, horses, opossums, birds
49
Angiostrongylus cantonensis paratenic hosts
crabs, shrimp, frogs, fish
50
Angiostrongylus cantonensis infective stage
L3 in IH or paratenic host
51
Canine neural angiostrongylosis
Hx of eating IH, progressive neurological signs, eosinophilic pleocytosis in CNS
Treat with prednisone, prognosis good
52
Angiostrongylus cantonensis clinical signs
eosinophilic meningitis, headache, paralysis
53
Angiostrongylus cantonensis treatment
Supportive care
54
Scientific name guinea worm of dogs (serpent on a stick)
Dracunculus insignis
55
Dracunculus insignis definitive host/location
dogs, foxes, cats, racoons, mink; subcutaneous tissues
56
Dracunculus insignis intermediate host
copepod
57
Dracunculus insignis paratenic host
frog
58
Dracunculus insignis infective stage
L3 in IH or paratenic host
59
Dracunculus insignis clinical signs
painful skin ulcers
60
Dracunculus insignis diagnosis
observe female under skin, see L1 from skin blister in water
61
Dracunculus insignis treatment
Fenbendazole, ivermectin (best results if treated within 90 days of infection)
62
Dirofilaria immitis definitive host/location
dogs, cats, ferrets, sea lions; pulmonary arteries, right ventricle
63
What are microfilariae?
Prelarval stage of Dirofilaria immitis
64
Dirofilaria immitis vector/intermediate host
mosquitos
65
What must Dirofilaria immitis be differentiated from?
Acanthocheilonema reconditum
66
Acanthocheilonema reconditum characteristics
Few in blood, progressive motion, "button hook" tail, a little smaller than D. immitis
67
Dirofilaria immitis occult infection
"hidden" infection, possibly due to single sex infection or small numbers, microfilariae NOT detectable
68
Dirofilaria immitis microfilarial periodicity
1. Noctural - microfilariae present during evening hours
| 2. Incomplete - microfilariae never disappear completely from blood in 24 hour period
69
Dirofilaria immitis infective stage
L3 from mosquito bite
70
Dirofilaria immitis prepatent period
6-7 months
71
How many species of mosquitos harbor L3?
How many can transmit heartworm?
How many are common vectors?
70 species
23 transmit heartworm
14 are common
72
Dirofilaria immitis clinical signs
Due to infection in right ventricle and pulmonary arteries (increased vascular resistence, decreased cardiace output)
Can cause villous endarteritis
73
Dirofilaria immitis mild infection
intermittent cough, exercise fatigue, mild radiographic signs
74
Dirofilaria immitis severe infection
Severe radiographic signs (enlarged R ventricle, pulmonary artery enlargement), PCV <20%, persistent cough, ascites
75
Vena cava syndrome
Worms obstruct blood flow, interfere with tricuspid valve function, heart murmur, severe lethargy and weakness
76
Dirofilaria immitis diagnosis
1. Detect antigen
| 2. Detect circulating microfilariae
77
When do dogs become antigen positive?
Most - 7 months post infection
Earliest - 5 months post infection
Missed doses of prevention may delay detection to 9 months post infection
78
When do dogs become microfilariae positive?
Earliest - 6.5 months post infection
| Dogs with missed doses of prevention, but still receiving it occassionally may never be microfilariae positive
79
How often should dog's receive antigen testing?
Annually
80
Should we doubt test results?
No, there is a high sensitivity and specificity
81
Antigen test: +
| Microfilariae test: -
1. Microfilariae not yet in circulation (maturing infection)
2. Use of preventative without removing adult worms
3. Use of microfilaricide without removing adult worms
4. Unisex infection (female)
5. Dog is true immune-mediated occult
6. Failure to use microfilariae concentration test
82
Antigen test: -
| Microfilariae test: +
1. Microfilariae of another species (Acanthocheilonema reconditum)
2. Microfilariae acquired transplacentally
3. Adult worms removed or died, but microfilariae persist
4. Contamination of test materials from previous sample
83
Antigen test: variable
| Microfilariae test: Neg. or Pos.
1. Fluctuating antigen level due to number of female worms, ages of worms, quality of sample
84
What is Wolbachia?
Wolbachia pipientis (only known species), gram negative bacteria related to ehrlichia and anaplasma, endosymbiote of Dirofilaria immitis
85
How is Wolbachia harmful to host?
Contributes to pulmonary and renal inflammation
86
Melarsomide treatment (age of worms affected and dose protocol)
NO activity in worms <4mo
| AHS recommends 3 dose treatment (one, wait 30 days, then two 24 hours apart)
87
How to remove microfilariae?
Moxidectin (Advantage multi)
88
Why wouldn't we want to specifically treat microfilariae?
High microfilarial numbers
| All preventatives have microfilaricidal properties to some degree
89
Special name for clinical heartworm disease in cats
Heartworm associated respiratory disease (HARD)
90
What is the pathogenesis of heartworm associated respiratory disease in cats?
Vascular and airway disease caused by early death of IMMATURE heartworms
91
Stage 1 heartworm infection in cats
Immature adults in pulmonary arteries, cats tolerate worms
92
Stage 2 heartworm infection in cats
Worms dying - pulmonary inflammation, thromboembolism
93
Heartworm infection diagnosis in cats
Diagnosis is very difficult, low microfilariae numbers, antibody and antigen tests not very good
