Host And Parasite Interactions Flashcards
Some parasites are minimally pathogenic but are considered
Opportunistic
What do the majority of parasites have
Pathogenic potential
Where is cryptosporidium or pneumocystis found
In immunocompromise patients. There is no treatment
What can lesions be caused by
Physical factors, parasites metabolism, host a reaction
How can parasites cause lesions by physical factors
By either attachment organelle and mouthpieces, by their migration in body, by the lumen obstruction of an organ Tissue destruction Necrosis by compression Bleeding Secondary infections Vectors
What is the typical amount of acetabulum on a parasite
Four
How can migration from the digestive tract to the preferred site happen
Via cavities or natural paths such as blood vessels and lymphatic system. Or directly through tissues such as fasciola hepatica
How can lumen obstruction of an organ happen
From the presence of the parasite or as an inflammatory reaction from the body
How does Dirofilaria Immitis obstruct
Obstructs the right ventricle and causes proliferative lesions in the pulmonary artery
How does paRasitic tissue destruction occur
From feeding, development. Multiplying within tissue and interfering with metabolism
What does toxoplasma do in terms of tissue destruction
Goes into the fetus. Can cause abortion or attack brain a neurological tissue. If I actually born there is a risk of developing schizophrenia as a child.
What does ostertagia ostertagi do to cause tissue destruction
Causes inflammation of the stomach mucosa. Hydrochloric acid producing cells are replaced by mucus producing cells
How does necrosis by compression of her
By growing causing a compression of the surrounding tissue. Atrophy, necrosis or loss of function due to nerve compression
What does Echinococcus granulosis do
Affects the liver and lungs. After consumption of infected intermediate host
What does diotophyma renale do
The roundworm of the kidney. Causes necrosis of right kidney
Describe bleeding caused by fasciola hepatica
Can be fatal in the liver
Describe what Ancylostoma caninum do
Attached to the intestinal mucosal as it feeds. So he creates an anticoagulant that continues the bleeding once detached.
What is the effect of bleeding as a physical factor
Anemia
How can parasites cause secondary infections
From migration. Makes holes
How can vectors cause lesions
From fleas, ticks, etcHaemobartonella, Lyme disease
How can parasites cause a reduction in growth rate
Through competition for food which is of importance in production animals since it reduces the food intake of host. Can also affect milk, wool, meat production
What does moniezia expansa affect and how is it transmitted
Ovines and it’s from an infected mite
How does diphyllobothrium Latum cause vitamin deficiency
It accumulates vitamin B 12 and it’s own tissues which is necessary for red blood cell creation and function of brain
How does parasitic toxin production work
Dermacentor Andersoni secrete a toxic substance in their saliva which gradually paralyzes and causes respiratory failure
How does trichuris trichurias toxins affect humans
Cause a rectal prolapse due to nerve paralysis
Why does giardia cause a greasy stool
Due to interference with lypolysis
What does trichinella do to the immune system
Suppresses T lymphocytes causing malfunction of macrophages
What does entamoeba histolytica do
Digests intestinal tissues
What are some host reactions to a parasite
Allergy Hypersensitivity eosinophilia Immune system unresponsiveness Hyperplasia Neoplasia Inflammation Granuloma
How can thysanosoma actinoides cause hyperplasia
Induce biliary canal hyperplasia
How does spirocerca lupi cause neoplasia
Causes osteosarcoma and fibrosarcomas in wall of esophagus
How does shistosoma haematobium cause neoplasia
Causes bladder cell carcinoma
What are annelids
Leaches
What are Acanthocephalans
Thorny headed worms
What are characteristics of Arthropoda
Segmented body, exoskeleton, jointed appendages
What are monogenetic Trematodes mostly considered
Ectoparasites Of aquatic species
What are digenetic Trematodes considered
Endoparasites in large GI tract. But can also be found in blood and lungs.
