Pathogenic Organism and Disease Terms - PowerPoint Presentation

Slide1

Pathogenic Organism and Disease Terms

Pathogenmicroorganism that produces diseaseA living organism of microscopic dimensionsNot all microorganisms are pathogensThe microorganism in the pictures is not a pathogen-does not produce a disease, in fact…Slide2

Pathogenic Organism and Disease Terms

Diseasedeviation from normalinfectious disease noninfectious diseasecontagious (communicable) diseaseiatrogenic diseaseidiopathic diseaseSlide3

Infectious Diseases

4 classes of agents (an agent is something that produces an effect)Bacterium/BacteriaVirus/VirusesFungus/FungiParasitesSlide4

BacteriaIs a living cell

Prokaryote cell – No NucleusMade up of cytoplasm, DNA, ribosomes, flagellaSlide5

Bacteria

Cocci _ roundStaphylococci– round, clustersSkin infections, wounds, food poisoningGram positiveStreptococci- round, chainsStranglesBacilli – rod shapedAnthraxEndospore – oval body inside, resistant

clostridiumRickettsia –rod shaped, smallehrlichia

Spirochetes

– spiral

LeptospirosisSlide6
Slide7

Staphylococci

Staphylococci- (cocci means round) – round, clustersSkin infections, wounds, food poisoningMRSAGram positiveHave thick wall that takes a stain (purple)Slide8

Streptococci

Streptococci-round, chainsGram positiveStranglesPinkeyeStrep throatNecrotizing fasciitisSepsis Slide9

Bacilli

Bacilli – rod shapedAnthraxE. coliSalmonellaListeriaClostridium Slide10

E. ColiGram negative

AnaerobicLower intestinesSlide11

clostridium

Gram positive rod shaped bacteriaAnaerobic (lives without oxygen)Food poisoningClostridium perfringens enterotoxinSlide12

Rickettsia

Gram Negative bacteriaIntracellular parasitesTyphusRocky Mountain Spotted Tick FeverSlide13

Spirochette

Lyme diseaseLeptospirosisSlide14

1. Examples of Infectious Bacterial Diseases

SwineYersiniaCattleE ColiMastitis

AnthraxCanineLeptospirosis

(

Lepto

)

Ehrlichiosis

(Tick Fever)

Bordatella

Bronchiseptica

(kennel cough)

Rabbit

Pasteurella

(Snuffles)

Tuleremia

(vector-ticks, flies)

Horse

Tetanus

Strangles

Cat

Enteritis

CystitisSlide15

BacteriaIs a living cell

Prokaryote cell – No NucleusMade up of cytoplasm, DNA, ribosomes, flagellaSlide16

Virus

Not a living cell! But are considered alive because they reproduce, grow, develop, adapt, use energy sources from their environmentMade up of genetic material/ nucleic acid (DNA or RNA) enclosed in a protein shellAll sorts of shapes but are extremely tiny/ cannot see with a regular microscopeSlide17

Viruses insert their genetic material into a living cellThe cell becomes the virus’ host.

The virus DNA/RNA becomes a part of the cells DNA so that during cell division the virus is being replicated and passed on.Eventually the virus’ DNA takes over, completely changes the host cell/ kills it’s host cell and continues to replicate and create lots more virusesSlide18

What about Retroviruses (Feline Leukemia and FIV)

constantly change/ difficult to treat Slide19

Virus vs Retrovirus

Virus tends to contain DNA which can be replicatedRetrovirus contains RNA which must be transcripted (“converted”) into DNA. this process is not accurate“mistakes” are made in the processDNA constantly varies because of the mistakesReason why retroviruses are harder to treat/ preventHIV, FIV, Feline LeukemiaSlide20

2. Examples of Infectious Viruses

CattleBovine Viral Diarrhea (BVD)CatsFeline PanleukopeniaCalicivirus

Feline Leukemia VirusFeline Immunodeficiency Virus

Rabies

-

most warm blooded animals

Dogs

Parvovirus

Distemper

Horses

West Nile Virus

Equine EncephalomyelitisSlide21

Bacteria

VirusRibosomesPresentAbsentLiving attributes

Living organism Opinions differ on whether viruses are a form of life or organic structures that interact with living organisms

Number of cells

Unicellular; one cell

No cells; not living

Structures

DNA and RNA floating freely in cytoplasm. Has cell wall and cell membrane

DNA or RNA enclosed inside a coat of protein.

Treatment

Antibiotics

Vaccines prevent the spread and antiviral medications help to slow reproduction but can not stop it completely.

Enzymes:

Yes

Yes, in some

Nucleus

No

No

Virulence

Yes

Yes

Infection

Localized

Systemic

Benefits:

Some bacteria are beneficial

Viruses are not beneficial.

Reproduction

Fission- a form of asexual reproduction

Invades a host cell and takes over the cell causing it to make copies of the viral DNA/RNA. Destroys the host cell releasing new viruses.

Size

Larger (1000nm)

Smaller (20 - 400nm)

Cell wall

Peptidoglycan

/

Lipopolysaccharide

No cell

wall.Protein

coat present instead

Comparison chart bacteria

vs

virusSlide22

PrionsAre proteins

Not aliveThey do not have DNA or RNAThey have an ability to reproduceCan cause inherited or transmissible diseasesSlide23

Prions

Prion diseases are fatal and cause progressive, neurodegenerative problemsliterally, holes in the brainThe brain resembles a sponge / diseases are called spongiform Examples of spongiform encephalopathies are…. 1) Scrapie….in sheep and goats 2) BSE ….”Mad Cow Disease”

3) Chronic Wasting Disease…wild deer and elkTransmitted by inherited disease, or ingested from tissue of infected animals (brain, spinal cord)Slide24

FungusIs a living cell…

a “plant” type cell with a stronger protein wall (chitin)Plants have a cellulose wall (a “sugar”)Mold, yeast, mushroomStudy of fungus is mycologyFungus “move” by growingSlide25

3. Examples of Infectious Fungi (mycoses)

Dermatophytes (Ringworm)Require keratin for growthThrushCoccidioidomycosis (Valley Fever)Blastomycosis (South East)HistoplasmosisCandida (yeast infection)Slide26

Budding yeastSlide27

Valley Fever

Coccidioidomycosis (disease)Round fungus (Coccidioides Immitis)Lives in the soilDormant during dry spellsDevelops as a mold with long filaments that break off into airborne spores when it rainsThe spores get into the air by disruption of soil

(construction, earthquakes, farming, dust storms)Slide28

4. Examples of Infectious Parasites

Heartworm (Dirofilaria immitis)Trichinella…TrichinosisHookworm (Ancylostoma), Whipworm (Trichuris vulpis), Roundworm (Toxocara)

Giardia (protozoan)Coccidiosis (protozoan)Slide29

Noninfectious Disease Classifications

Classifying diseases helps aid the veterinarian in obtaining a diagnosisHelps the diagnostic processClinical signs and symptoms could be the result of several different disordersDifferential diagnosis-a list of possible causes of diseaseRule Outs-ruling out possible causes of disease through diagnostic testing, observation, trial treatmentSlide30

Metabolic

-disruption of normal chemical reactionsDiabetes, hypothyroidism, hyperthyroidism, Cushings, AddisonsSlide31

Anomalies

– Congenital Birth DefectsCleft palate, deaf, retinal dysplasia, dwarfismSlide32

Degenerative

– progressive, permanent, longterm deteriorationDJD (osteoarthritis), Bovine Spongioform Encephalopathy (BSE)Slide33

Trauma

– Traumatic reticuloperitonitis, high rise syndrome, sucking chest wound, diaphragmatic hernia, peritonitis, prolapsed uterusSlide34

Toxins

- ingestion, inhalation, contactAntifreeze, misapplication of flea and tick products, warfarin (rat poison), toads, OTC medications, illegal drugs, plantsSlide35

Immune

Immune Mediated Hemolytic Anemia (IMHA), System Lupus Erythematosus (SLE), Pruritis and Atopy (itchiness and hairloss) [allergies]Slide36

Iatrogenic

- a condition that develops as a result of treatmentHyperadrenocorticism (Cushings)- can be caused by treatment for a severe allergy problemSurgery-excision of Thyroid glad to treat hyperthyroidism in cats…parathyroid may also be removed causing iatrogenic

hypoparathyroidism.Slide37

Idiopathic

- no explanation for underlying cause of the diseaseIdiopathic seizuresIdiopathic renal hematuriaSlide38

Neoplasm

- benign or malignant tumorSlide39

Nutrition

– Acute acidosis in ruminants, malnutrition, skeletal disease, hypoglycemia, obesity, iodine deficiencySlide40

MADTIN

TTraumaToxinsIImmuneIatrogenicidiopathicNNeoplasmnutritional

MmetabolicAanomalie

D

degenerativeSlide41

NonInfectious Disease Classifications

Metabolic-disruption of normal chemical reactionsDiabetes, hypothyroidism, hyperthyroidism, Cushings, Addisons

Anomalies – Congenital Birth DefectsCleft palate, deaf, retinal dysplasia, dwarfismDegenerative

– progressive, permanent,

longterm

deterioration

DJD (osteoarthritis), Bovine

Spongioform

Encephalopathy (BSE)

Trauma

–

Traumatic

reticuloperitonitis

, high rise syndrome, sucking chest wound, diaphragmatic hernia, peritonitis, prolapsed uterus

Toxins

- ingestion, inhalation, contact

Antifreeze, misapplication of flea and tick products,

warfarin

(rat poison), toads,

OTC medications, illegal drugs, plants

Immune

Immune Mediated Hemolytic Anemia (IMHA), System Lupus Erythematosus (SLE)

Pruritis

and

Atopy

(itchiness and

hairloss

) [allergies]Slide42

NonInfectious Disease Classifications

Iatrogenic- a condition that develops as a result of treatmentHyperadrenocorticism (Cushings)- can be caused by treatment for a severe allergy problemSurgery-excision of Thyroid glad to treat hyperthyroidism in cats…parathyroid may also be removed causing iatrogenic hypoparathyroidism

.Idiopathic- no explanation for underlying cause of the disease

Idiopathic seizures

Idiopathic renal hematuria

Neoplasm

-

benign or malignant tumor

Nutrition

–

Acute acidosis in ruminants, malnutrition, skeletal disease, hypoglycemia, obesity, iodine deficiency

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3 SEIZURE CASES

Seizure Case 1: A 3 month old male toy poodle. The dog is strictly a house dog and does not run free, In addition to the seizures, it has had intermittent diarrhea and is quite thin. Differential Diagnosis (DfDx): Developmental Disorder- brain malformation Hypoglycemia-could be secondary to poor diet, diarrhea, intestinal parasites Head Trauma- not likely with indoor dog Toxins-potential for ingesting medications or illegal drugs, chocolate

Infectious causes of encephalitis- Distemper Idiopathic epilepsy-very unlikely due to age of dogSlide44

Seizure Case 2:A 2 ½ year old male golden

retreiver. This dog is in excellent physical condition and has been eating well. This dog is free to roam the neighborhood and recently had one episode of vomiting and one episode where it was limping and stiff.DfDx: Idiopathic epilepsy-this is high on the list because of age and breed of dog at the onset of seizures. Head Trauma-the recent limping and stiffness raises this possibility Toxins- the list is long, but possibilities include insecticides, chocolate Liver Disease-definitely needs to be ruled out but dog has been doing well otherwise Infectious Encephalitis Slide45

Seizure Case 3:A 14 year old female schnauzer. This dog had its first seizure and since that time has not been acting normal. There has been some weight loss and a poor

appetitie, and the owners feel the dog can no longer see. The dog is strictly an indoor dog with no history of trauma.DfDx: Metabolic Disease-liver dx, hypogylcemia (insulinoma in the pancreas), Diabetes Neoplasia

- the age of the dog, the blindness, lack of normalcy after the seizure make this a high likelihood Ideopathic epilepsy-very unlikely with the age of the animal