Cytology of Infectious Organisms Flashcards
Dr. Short
What does intracellular bacteria mean?
active infection present
What does a pleomorphic population of bacteria mean?
contamination, mixed bacterial infection
What are pathogenic cocci properties?
usually gram +
staph pseudointermedius (clusters)
streptococcus (chains)
dermatophilus - railroad tracks
What is the causative agent of rain rot?
dermatophilus congolensis
What are bacilli? Give examples
small rods, usually gram -
e.coli, pasteurella, pseudomonas
filamentous rods: nocardia, actinomyces
- sulfur granules common
What are characteristics of actinomyces.nocardia?
commonly associated with subcutaneous lesions and draining tracts
slow to grow - need both aerobic and anaerobic culture, alters lab to what you are looking for
Sulfur granules are commonly associated with what pathogen?
actinomyces/nocardia
What are properties of. mycobacterium?
different species of mycobacteria can cause different clinical signs
- can infect skin, respiratory tract, or disseminate
negatively staining bacilli, often with macrophages, acid-fast
What is this leproid nodule on the ear maybe from?
mycobacterium
Bacteria?
mycobacterium
What kind of bacteria is bordetella? What is it commonly associated with?
coccobacilli
seen associated with ciliated respiratory cells
What does campylobacter cause and how does it appear on cytology?
diarrhea - young animals, puppies <6 months, often self-limiting
seagull shaped organisms - fecal cytology
What is clostridium, where is it on the body, and what does it cause?
spore-forming bacilli
commensal GI organism until opportunity - overgrowth can lead to diarrhea, anorexia, vomiting
> 5/100x field is abnormal
“safety pin”, “tennis racket”
What are the types of fungal infections?
What does aspergillus cause? What does it look like on cytology?
cause of mycotic rhinitis, as well as ocular and guttural pouch disease in horses, can become systemic
need culture
slender hyphae, 45 degree branching
What is malassezia and how does it appear on cytology?
opportunistic, commensal yeast of the skin
budding, broad-based yeast “footprint shape”, can be associated with mixed inflammatory reaction
What does blastomyces cause, and what does it look like on cytology?
typically causes systemic disease, localized infections possible
lungs most often affected but can affect eyes, skin, etc
thick, double-walled, unencapsulated, refractive cell wall, often budding “broad based budding”
What is the organism?
blastomyces - broad-based budding
What is cryptococcus, and what are its effects?
inhaled —> spreads throughout body via direct extension or hematogenously to other organs —> SQ swellings over bridge of nose
What does crytopcoccus look like on cytology?
round/oval organism with thick, clear capsule - may see narrow-budding yeast
Organism in a cat?
cyrptococcus
What are the characteristics of histoplasma?
infections can be localized or disseminated - LUNGS
What does histoplasmosis cause?
pyogranulomatous inflammation with phagocytized organisms - very small yeast, round-oval, crescent shaped nucleus, thin clear cell wall halo
Organism?
histoplasmosis
These skin lesions are indicative of what fungal infection?
histoplasmosis
What is coccidioides?
found in desert soil, dimorphic fungi that forms spherules, then internally divides into endospores
What does coccidioides lead to?
pulmonary disease
What does coccidioides look like on cytology?
spherules: variable in size, round, blue, double-walled, almost appear to have a “fold” or “crease”
- endospores seen within the spherules, or with Macs/neutrophils
Fungal infection?
coccidioides
snowstorm on radiographs
What are properties of sporothrix?
can cause cutaneous or disseminated disease
How does sporothrix appear on cytology?
tiny, round-elongated shaped yeast with eccentric nucleus, thin halo
Look at leishmania
Look at giardia
Look at tritrichomonas foetus
cause of diarrhea in kittens
Look at tachyzoites
seen in protozoal infections of neospora, toxoplasma, sarcocystis
appear as crescent-shaped or oval
Look at helminths
lung worms - can be detected on transtracheal washes, bronchoalveolar lavage
