Lecture 1: Intro to Clinical Practice and Essential Microbiology and Clinical Pathology Flashcards
What stains are included in gram stain
crystal violet, iodine, safranin and organic solvent
gram __appear red on gram stain and gram ___ appear dark blue
negative, positive
Staining reflects the ___of the cell walls
molecular characteristics
What type of bacteria is filamentous
actinomycete
what is saprophyte bacteria
bacteria that lives in environment
what bacteria is spiral shaped and typically requires a special stain
spirochete
what are some examples of spirochete bacteria
treponema, borrelia, leptospira
what are virulence factors
characteristics that confer pathogenicity
classification of bacteria is clinically important especially in ___therapy while cultures are pending
empiric therapy
What diseases do Streptococcus equi zooepidemicus and streptococcus equi equi cause
S. Zooepidemicus: pneumonia
S. Equi: strangles
T or F: MRSA is zoonotic
true
gram __causes endotoxemia due to ___in their cell walls
negative, LPS
endotoxemia is common in horses with ___
enterocolitis
what are some clinical signs of endotoxemia
fever, tachycardia, congested (red) MM, laminitis
Rhodococcus equi is gram ___, facultative __
positive, intracellular
R. Equi is able to invade and survive in ___ due to what virulence factor
macrophages, VapA
what does R. Equi cause
pulmonary abscesses in foals
what is treatment for R. Equi
- Macrolide antibiotic
- Rifampin- penetrates abscesses
T or F: you can use macrolide antibiotics in adults
false- causes diarrhea
clostridia is a gram __, obligate __
positive, anaerobes
clostridial myositis is a sequela to ___
IM injections, often banamine
what are some signs of clostridial myositis
heat, swelling, subcutaneous emphysema, foul odor
what is treatment for Clostridial myositis
Penicillin G, fenestration to oxygenate tissue
DNA or RNA viruses: have higher mutation rates
RNA
enveloped or nonenveloped: have increased sensitivity to desiccation, detergents
enveloped
all viruses are obligate ___ and require ___ to replicate
intracellular parasites, host cell machinery
viruses often use existing ___ to enter host cells
cell surface receptors
what virus often results in latent infection
herpesviruses
influenza viruses are characterized by what two major surface proteins
- Hemagglutinin (H)- involved in viral attachment
- Neuraminidase (N)- involved in release of virus from infected cell
what influenza strain is most common in horses
H3N8
how does EHV-1 enter cell
via MHC-1
what does EHV-1 cause
respiratory signs, neurological signs, abortion
what antiviral is useful for EHV-1
valacyclovir
t or f: vaccine for EHV-1 prevents neurological disease
false— only prevents respiratory signs and abortion
yeast or mold: single cells
yeast
yeast or mold: filamentous
mold
fungal cell wall contains __and therefore not susceptible to antibiotics
chitin
fungal cell membrane contains ___
ergosterol
what drugs target ergosterol
amphotericin B, ketoconazole, fluconazole
most fungi are obligate __
aerobes
what is the most common host response to fungal infections
granuloma
What wrong and what can it lead to
corneal ulcer that can lead to fungal keratitis
what are the most common organisms involved in fungal keratitis
aspergillus, fusarium
What is the treatment for fungal keratitis
- Anti fungal- voriconazole, natamycinm itraconazole, fluconazole, ketoconazole
- Anticollangenases
- Anti-inflammatories
what is the most common cause of fungal pneumonia
aspergillus
what causes oral candidiasis in sick foals
Candida albicans
what is the most common blood collection site in horses
jugular venipuncture
what is the red top or serum separator tube used for
basic chemistry
what is the EDTA, lavender top used for
CBC, ACTH
What is the blue top, sodium citrate tube used for
coagulation panels
what is the green top, sodium/lithium heparin tube used for
tests run on plasma
what is the yellow top, acid citrate dextrose tube used for
blood typing
what respiratory fluid collection samples an isolated location in small airways and is indicated when there is suspected diffuse (allergic) dz
bronchoalveolar lavage
what does a transtracheal wash sample from
pooled secretions from lower airways in entirety
when is a transtracheal wash indicated
suspected localized disease (pneumonia)
what type of respiratory fluid collection is indicated for S. Equi
guttural pouch lavage
where should you perform an abdominocentesis
lowest point of abdomen to the right of midline
what location is most common for spinal fluid collection
lumbar
T or F: rouleaux formation of erythrocytes is common in horses
true
t or f: foals are born hemoconcentrated
true
what can cause erythrocytosis
- Splenic contraction
- Dehydration (relative /hemoconcentration)
- Polycythemia
what are the possible causes of anemia
- Loss of RBC-hemorrhage
- Destruction of RBC- immune mediated, neonatal isoerythrolysis
- Decreased production of RBC- bone marrow suppression
t or f: horses release reticulocytes into their peripheral blood
false
what sample is needed to evaluate anemia in horses
bone marrow biopsy
hemorrhage and replacement of fluid volume may take __hrs to become apparent
12-24hrs
foal presents with icterus and lethargy- blood smear performed. What is likely cause
neonatal isoerythrolysis
What test can be done to distinguish between rouleaux and agglutination
saline dispersion test
what are the normal % for macrophages, lymphocytes, neutrophils, mast cells and eosinophils in a BAL
macrophages: 50-70%
Lymphocytes: 30-50%
Neutrophils: <5%
Mast cells: <2%
Eosinophils: <0.5%
what is the protein, cellularity and color in normal abdominocentesis
protein: <2mg/dL
Cellularity: <5,000u/L
Color- clear, pale yellow
what is the normal protein, cellularity, and color in CSF
protein: 20-124mg/dL
Cellularity: <7/uL
Color: clear
horse serum/plasma more __in color than other species
icteric
increase in indirect bilirubin occurs in horses with __
anorexia
what is the normal pH for horse urinalysis
7-9
what is normal USG for horses
1.020-1.050
what is renal threshold for glucose in urinalysis
160-180mg/dL
t or f: foals have hyposthenuric urine
true
