Skin, Hair & Faecal Samples Flashcards
What ppe should be worn during skin examinations?
Gloves
Apron
Long sleeves
In some cases masks
Good hand hygiene
What patient preparation is required for skin and hair analysis?
-sedation of conscious
-check if on any medications (some treatments must be stopped before sampling)
-consent for investigation
What diagnostic tests are available for skin and hair?
-skin scrapes
-hair plucking
-sellotape impressions
-coat brushing
-wet cotton wool test
-swab sample
-tissue biopsy
How is coat brushing test carried out, and what can it identify?
-restrain animal
-comb to collect samples
-brush in one direction
-transfer sample to wet cotton wool or microscope slide
-fleas, walking dandruff, ticks, lice, ear mites, eggs
What are the advantages of carrying out coat brushing?
-simple to perform
-not invasive
-not stressful
-cheap
How is tape impressions carried out, what can it identify?
-restraint
-identify correct area to be sampled
-part the fur
-impression took 2-3 times on same spot
-transferred to microscope slide
-fleas, lice, mites
What are the advantages and disadvantages of using tape impressions?
A
=cheap and easy
=rapid
=can be used in hard to reach places
D
=only used on dry areas
How should hairs be plucked for examination?
-use tweezers or forceps
-individual hairs plucked
-important that the hair root is plucked out
-hair taken from edge of lesion if present
What are the advantages and disadvantages of plucking hairs?
A
=quick
=simple
D
=can be painful
=may not get positive sample
How are skin scrapes carried out, what can it identify?
-restraint
-conscious or sedated
-use scalpel blade to remove the surface layer of the skin
-imprimatur to go deep enough to cause petechial blood oozing
-transferred to microscope slide
-deep burrowing mites
What are the advantages and disadvantages of using skin scrapes?
A
=diagnoses deeper dwelling parasites
=quick
=simple
D
=painful
=stressful
=must ensure concert technique is used
How are ear swab samples carried out, what does it identify?
-must be sterile
-charcoal swabs used
-cotton buds smeared onto microscopes
-sample can be sent off to external lab
-identifies bacteria, fungi, yeast infections
How are pustules examined?
-contents of pustule extracted using a sterile needle with 1-2ml syringe
-expressed directly onto microscope slide
-smear or squash microscope prepared
-samples examined fresh or stained
How is a biopsy carried out?
-required light sedation of full GA
-minor surgical procedure
-uses biopsy punch to remove a circle of diseased skin when the problem is deeper than the epidermis layer
-sample usually sent to external lab
Why is faeces examined?
Provides info on the health of the GI tract and how well it is functioning
How should faeces be collected, what are the 2 methods?
-fresh non preserved stool specimen required
-multiple samples may be required
-directly from rectum or ground
How is faeces collected from the rectum?
-carried out gently with gloved finger and sterile lubricant
-patient gently but firmly restrained
-use dull to ensure correct patient sample in multi pet households
How is faeces collected from the ground?
-transfer sample into sterile container using gloves
-collect top section of sample, that has not had contact with the ground
-fill container as much as possible and label sample
-wash hands
How can faeces be preserved?
-can be refrigerated for up to 7 days
-cannot be frozen
-10% formalin may be used to preserve samples
What is in the normal content of faeces?
-water
-undigested food
-enzymes such as trypsin
-bile product
-mucous
-bacteria
-epithelial cells
-blood and hair from prey
What observations can be made about faeces?
-colour
-consistency
-smell
-fatty or mucous
-identifiable objects
-parasitic evidence
How is a direct smear carried out for faeces?
-small amount of faeces is spread on microscope slide
-mix faeces with saline or water on microscope slide
-cover slip applied
-examine under microscope at low then high magnification
-quick but may not detect low parasite burdens
What are the 2 concentration methods carried out to examine faeces?
Flotation
Sedimentation
How is a flotation test carried out?
-mix faeces and solution
-put mixture through sieve
-put filtrate in test tube
-leave for 5 minutes
-pour of supernatant and add flotation solution
-fill test tube to top
-place cover slip on tip
-leave for 10-20 mins
-lift cover slip off vertically and place on slide
-examine on low power
What is the process of centrifuging faeces in flotation tests?
-requires centrifuge which holds a 15ml test tube
-spun at 1,000 to 1,500 rotations per minute for 3 to 5 mins
How is a faeces sedimentation test carried out out?
-mix 2g faeces with tap water
-strain
-half fill centrifuge tube with filtrate
-spin at 1500 rpm for 5 mins
-pour of supernatant
-use pipette to put some e sediment on slide
-apply cover slip
-iodine mixed in with sediment before examination under low power
What is a modified McMaster technique?
-quantitive examination
-round worm eggs float to surface
-markings moved to slide for examination
-determines number of eggs per gram of faeces
