pathology 4 - change and incidental findings Flashcards
what is algor mortis?
cooling of the body after death - take longer in some species eg. sheep take longer as they have wool. or horses have a lot of abdominal viscera.
To avoid many PM changes what should you do? (3)
examine as soon as possible after death
store at 4 degrees celcius
freeze carcass (may damage tissue when thawed so fix any organ sample first)
what is rigor mortis? effect of temp and ph? duration depends on? reversed by what?
2-4 hours after death - prolonged muscle contraction due to cross bridges becoming stuck from lack of oxygen and ATP to dissociate them. animal becomes rigid. higher temp = faster onset. duration depends on amount of glycogen present.
higher PH can delay it
reversed by autolysis
explain PM clotting? How is it different from thrombosis?
thrombosis would be hard to dislodge and would be attached to vessel wall, whereas clotting from PM conforms to the vessel wall and is easy to remove.
What is hypostatic congestion?
if the animal is lying on one side when it dies……effect of gravity causes assymetric congestion of a lung and other organs. the two lungs may look very different due to this.
what is pseudomelanosis?
green/black due to bacteria converting iron to iron sulphide in eg. GI tract. only surface flat lesions.
what is biliary imbibition?
leeching of bile from the gall bladder to organs next to it eg. intestines/liver.
what is putrefaction?
invasion of dead tissue by anaerobes - produce hydrogen sulphide which produces excess gas and emphysema. (green/brown)
what is autolysis?
self destruction/digestion from enzymes. different rates depending on tissue. eg. pancreas, stomach, intestine> kidneys>skin/muscle.
What are agonal changes?
just around the time of death - circulatory failure. eg. spleen congested ((huge) or reguritation - no inflammation associated if it was PM change. barbituate crystals in heart. GI intusussception (spasm) - again no inflammation or congestion associated if PM change.
Neoplasia: - also looks like nodular hyperplasia!!!! what is this?
nodular hyperplasia is an indcidental finding!!. common in the liver, spleen, adrenals of a dog. very well differentiated cells. multiple nodules in older dogs. increased number of cells/volume. is a compensatory mechanism not a neoplasia - it is just an incidental finding.
What is a neoplasia?
a growth outside the control of the body - it is abnormal. uncoordinated with normal tissues in the absence of a stimulus and may become malignant. abnormal growth of cells.
If you see some lesions with inflammation associated what should you do?
probably not a Pm change so you should take a sample and biopsy and send it away or examine it. look at the animals history.
what does a cats kidney look like?
pale colour and very prominent vessles.
when is neoplasia significant?
if it looks systemic - multiple lesions then may be malignant. may be more significant on the spinal cord as it has no space to grow and may compress the cord etc even it is benign. if on the spleen - not so serious? but even then it may haemorrhage or become malignant.
