Flashcards in Parasite 2 Deck (79):
1
Tissue response to Helminths and Vermin?
Eosinophilic
2
What are the eosinophilic responses?
1) IgE, mast cells
2) Eosiniphilic chemotaxic factors
3) IL-4 and IL-5
3
Function of IL-4?
Switch to make IgE
4
Most important fatal helminth disease in humans?
Schistosomiasis
5
Death from Schistosomes caused by?
Hepatic granulomas and fibrosis
6
What does Schistosomiasis haematobium in Africa cause?
Hematuria/obstruction of bladder
Predisposition to squamous cell carcinoma of bladder
7
Where are sporocysts of Schistosomiasis?
Fresh water snails
8
How do fresh water snails infect humans?
They give rise to cercaria that penetrate through skin
9
Where do schistosome migrate after skin penetration?
Peripheral vasculature to portal venous system and pelvic venus system
10
How does tissue react to schistosome eggs?
Granulomas and fibrosis
11
What completes life cycle of schistosomes?
Eggs shed in feces that hatch in water
12
What causes the hepatic damage of schistosomes?
Toxic products and cell mediated immunity
13
Which interleukins result in induction of IgE synthesis, mastocytosis, and eosinophilia?
IL-3, 4, and 5
14
Resistance to re-infection correlates with what?
IgE levels
15
Eggs induce lymphocytes to secrete what?
Fibrogenic factors
16
Hallmark of Schistosomiasis?
Hepatic fibrosis out of proportion to parasite injury
17
Pathology of Schisto?
Calcified pinhead granulomas form around schisto egg
18
What do schisto granulomas induce?
Macrophages, lymphocytes, neutrophils, and eosinophils
19
Appearance of portal fibrosis in Schisto?
Pipestem
20
Pipestem fibrosis results in what in Schisto?
Portal hypertension
Splenomegaly
Esophageal varices
Ascites
21
How does one get liver flukes (Clonorchis siensis)?
Eating improperly cooked fish
22
Where do adult flukes live?
Biliary ducts
23
How long do flukes live?
20 years
24
Chronic infection with liver flukes can cause what?
Cholangitis, cholelithiasis, pancreatitis, and cholangiocarcinoma
25
How does one get Taenia saginata?
Ingestion of undercooked beef
26
How do you get Taenia solium?
Ingestion of undercooked pork
27
Which Taenia causes Cysticercosus?
T. solium
28
How does T. solium cause cysticercosus?
Eggs ingested, larvae hatch, penetrate gut wall, hematogenous dissemination results in cysts in CNS.
29
Which cysts in CNS cause problems?
Degenerating cysts. Intact cysts cause little host reaction
30
Echinococcus is known as what?
Canine tapeworm
31
How does Echinococcus normally present?
Asymptomatic and chronic
32
Hydatid cysts most commonly associated with what?
Echinococcus
33
Hydatid cysts most commonly in what?
Liver and lungs
34
Liver disease in which Echinococcus is almost always fatal?
E. multilocularis
35
Hydatid cysts of which Echinococcus can cause anaphylactic reaction?
E. Granulosus
36
Most common parasite in US?
Pinworms (Enterobius Vermicularis)
37
How are pinworms spread?
Spread by oral ingestion of eggs from anus
38
Most common symptom of pinworms?
Anal itching
39
Lifespan of pinworms?
2 months
40
Worms 3-4 the size of pinworms common in the tropics?
Whipworm (Trichuris trichura)
41
What can whipworm cause?
Local hyperemia and lesions of colonic mucosa
42
Common hookworms?
Hookworms (Necator amricanus/Ancylostoma duodenale)
43
Hookworms attach where?
Upper levels of small intestine
44
How is hookworm transmitted?
Infectious larvae, not eggs
45
Where do hookworm larvae penetrate?
Between toes
46
How does dissemination of Ascaris, Hookworms, and Strongyloides work?
Ingestion of eggs -> Bloodstream -> Lungs -> Invasion of filariform larvae -> esophagus -> Adult in intestine
47
When hookworm penetrates skin what is left?
Small itchy papule where they penetrate skin
48
What can result from hookworm traveling through lung?
Mild pneumonitis
49
Most significant signs and symptoms from hookworm?
From ingestion of host blood
0.2ml/worm/day
50
What does Strongyloides parallel in distribution and life cycle?
Hookworm
51
How does Strongyloide get in?
Filaria through skin
52
Important reservoirs for Strongy?
Cats and dogs
53
How does Strongy present?
Usually mild, but in immunosuppressed hyerinfection may result with severe pneumonitis and duodenitis
54
2nd most common parasite of humans?
Ascariasis
55
Where are Ascaris usually living unattached?
Small intestine
56
Greatest danger of ascaris?
Abnormal migration in body to block biliary ducts/obstruction of small intestine
57
4 small intestinal parasites?
1) Giardia
2) Hookworm
3) Stryongyloides
4) Ascaris
58
How does one get Trichinella spiralis?
Ingestion of improperly cooked pork
59
What do the larvae do in Trichinella?
Penetrate tissues, disseminate in blood, and encyst in muscle
60
In trichinella what do trapped larvae in the lungs cause?
Eosinophillic infiltrate
61
Trichinella has what effect on heart?
Patchy interstitial myocarditis with eosinophilia and giant cells resulting in scarring and heart failure
62
Most effective treatment when dealing with larval migrans syndromes?
Corticosteroids and antihistamines to reduce inflammation
63
Cutaneous larval migrans known as?
Ancylostoma
64
Cutaneous larval migrans associated with?
Hookworms of dog and cat
65
Cutaneous larval migrans is occupational disease of who?
Plumbers, construction workers, duck hunters, and anyone exposed to infected soil
66
What is visceral larval migrans?
Infection of dog and cat ascaris with widespread and damaging dissemination of larvae throughout body
67
Who normally gets visceral larval migrans?
Puppies spread to children
68
What is known as neural larval migrans?
Balisascaris
69
Who gets Balisascaris?
Children who eat dirt and have poor hygiene
70
Lymphatic filariasis (Wuchereria bancrofti) is transmitted by what?
Mosquito
71
Where do larvae develop of Lymphatic filariasis?
Lymph channels
72
River blindness is caused by what?
Onchocerca volvulus
73
What does Onchocerca volvulus cause?
Blindness
74
Body lice and head lice cause what 3 disease?
1) Rickettsia prowazeki
2) Rochalimaea quintana
3) Borrellia recurrentis
75
Blue spots indicative of what?
Crab louse
76
Where do Chigger's take up residence?
Hair follicles
77
What causes Chigger intense local inflammatory response?
Digestive enzyme
78
Rhinosporidiosis causes what?
Granulomatous of mucous membranes resulting in polyp formation
79