scott@vtx-cpd.com
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Replying to Samantha H. 25/04/2023 - 11:59
Hey Samantha.
I think that is a great point… all of our own opinions and attitudes towards these subjects will be different. For me the main thing is that we can discuss these topics freely and remember that everyone is different.
I think we have a long way to go with this stuff, but 100 times better than when I first graduated… which was a wee while ago now! 🙂
Thanks again for your comments, so glad you are part of the course.
Scott 🙂
Replying to Steph Sorrell 25/04/2023 - 10:27
Thanks Steph.
This is useful. I think this comes back to the ability to make individual workplace plans for individual people! I think we need to become more open as a profession to the fact that we will all have different needs, especially in the work environment.
Thanks again.
Scott 🙂
Hello Tessa!
Never late to the party! It is great to have you here. I hope you are enjoying the course so far!
Great question! The answer does depend a little on the methodology the lab is using for the test. False positives can occur for several reasons. This can be seen if there are other substances in feces with peroxidase like activity, including enzymes in plants and meat-based diets (Cook et al 1992). Plants have catalases and the prosthetic group ferriprotoporphyrin IX (hemin) which has higher enzymatic activity than haemoglobin. False positives can be seen if the animal ingests or has a diet rich in plants with high endogenous peroxidase (beets, canteloupe, broccoli, cauliflower).
In short, I would try and do a vegetarian diet if possible! Purina HA is a good option as soya based. Having said that, Purina Gastrointestinal EN did not seem to affect the test in this study:
https://pubmed.ncbi.nlm.nih.gov/32196727/
Hope that helps.
Scott 🙂
Replying to Rachael Porter 21/04/2023 - 19:11
No problem!
I hope it helped, let me know if you have any other questions.
Scott 🙂
Replying to Magda Upton 19/04/2023 - 13:41
Hey Magda.
I thought it was super interesting. Have you ever used pancreatic enzymes like this in pancreatitis cases?
Scott 🙂
Replying to Samantha H. 19/04/2023 - 12:49
Hey.
It is a really interesting point, Samantha. I also would feel nervous sharing personal details about my mental health. Got me thinking about why that was though. I think I have always thought that it would be held on record and held against me in some way. I am much more open now about discussing my needs with an employer from a physical and mental perspective. I would hope that then this translates into better working practices for everyone.
Glad you are enjoying the course.
Scott 🙂
Replying to Helen S. 19/04/2023 - 13:04
Thanks so much Helen.
This is very helpful! I think we have to make it a non-negotiable. I suppose it comes from a change in culture and leading by example. If everyone in the team is taking a break… it becomes harder for others to refuse and plow through!
Scott 🙂
Replying to Ornella R. 17/04/2023 - 22:20
Hey Ornella.
This is great news about the cat. My understanding is that the protein in Fortiflora is hydrolysed. I will double-check this with Purin though!
I think with chronic disease, even if just vomiting, there is indication for biopsies. There could still be small intestinal disease with a normal cobalamin.
Thanks for sharing the paper! I think if we all had TEG in our lives decision-making would be much easier! I would say that in cases of PLE with lower than reference albumin, there would be a rationale for clopidogrel. Thankfully we do not see too many cases that develop clinically significant thromboembolic disease.
Hope that helps.
Scott 🙂
Replying to Liz Bode 17/04/2023 - 10:41
Thanks Liz!
Very helpful!
Scott x
Hey Ornella.
Thanks for the questions.
I will pass these on to Hilary and let you know.
Scott 🙂
Replying to Tessa Verkade 20/04/2023 - 12:16
Hello Tessa.
Great points and great questions!
Honestly, I must admit I am not finding hypoadrenocorticism that often in chronic GI patients. These papers are probably most helpful:
https://pubmed.ncbi.nlm.nih.gov/35118742/
https://pubmed.ncbi.nlm.nih.gov/32573832/Although maybe not that common, I still think it is an important thing to rule out.
Hope that helps.
Scott 🙂
Replying to Magda Upton 19/04/2023 - 13:52
Thanks Magda.
I agree. I think that if there was any doubt about the diagnosis from the ACTH stim… the rest of the haematology and biochemistry is indeed supportive.
The administration of glucocorticoids before an ACTH stimulation test can interfere with and/or cause decreased response to the test. Most synthetic glucocorticoids, including prednisone and methylprednisolone, cross-react with the cortisol assay, which can cause falsely increased results. Dexamethasone and triamcinolone do not.
So, if a steroid is given just before the test, dexamethasone is slightly less of a concern. Other short-acting glucocorticoids (such as prednisone) should be withheld for 12–24 hours before the test. Longer-acting glucocorticoids, such as methylprednisolone acetate, should be withheld for at least 4 weeks before the test to avoid cross-reactivity.
The administration of glucocorticoids decreases endogenous ACTH concentrations, which causes atrophy of the adrenal cortex. A blunted response to the ACTH stimulation test is expected in patients that have received glucocorticoids (oral, parenteral, or topical) within about a month of the test or longer in case of longer-acting glucocorticoids.
In short – If a suspect Addisonian patient is given a one-off dexamethasone, the ACTH stimulation can be performed, because dexamethasone does not cross-react on the cortisol assay and one dose would not cause complete suppression of the cortisol levels. One dose of dexamethasone may slightly decrease adrenal cortex response to ACTH stimulation.
However, this suppression is likely small and will not affect the ability of the test to diagnose or rule out hypoadrenocorticism.Thanks again. Hope you are having a great week.
Scott 🙂
Replying to Ornella R. 15/04/2023 - 18:36
Hey Ornella.
I agree! I would be suspicious of Addison’s based on these results. You bring up a really good point regarding basal cortisol. It is a good test to rule Addison’s out in a patient with more chronic signs (particularly the GI patient). If you have a patient in an adrenal crisis, it is not that helpful. You need to do an ACTH stimulation test in a crisis. Basal cortisol can also be surprisingly low in normal patients! I see many basal cortisol results that are <10 nmol/l, which go on to stimulate completely normally.
Have a great week!
Scott 🙂
Hello everyone!
Just wanted to say another massive thank you to Felipe for a brilliant session.
Let me know if you have any questions.
Scott 🙂
Replying to Kathryn B. 15/04/2023 - 08:02
Hey Kathryn.
I hope you are well. I agree, basal cortisol is only really useful in well patients. In sick patients with a higher index of suspicion of Addison’s, I would do the ACTH stim! Many of the Addison’s dogs that we see have very low cortisol results pre and post-ACTH… like <10/<10... I thought this one was interesting as there was a wee bit of stimulation.
In a dog with normal adrenal function, injection of ACTH should result in a surge of cortisol secretion from the adrenal glands. Therefore, serum cortisol concentration before ACTH administration is expected to be between 14-165 nmol/l and after ACTHst it is expected to be >55 nmol/l. In a dog with HA, the adrenals have been destroyed and are unable to mount an appropriate response to ACTH. In most dogs with HA, serum cortisol concentrations before and after ACTHst are 27 nmol/l (undetectable). A small number of dogs with HA can have serum cortisol concentrations between 27-55 mcg/dL after ACTHst. In this case, the adrenal axis may have been suppressed a little by the dexamethasone, so if there was any doubt, I would repeat the ACR+TH stim in 48-72 hours.
The administration of glucocorticoids before an ACTH stimulation test can interfere with and/or cause decreased response to the test. Most synthetic glucocorticoids, including prednisone and methylprednisolone, cross-react with the cortisol assay, which can cause falsely increased results. Dexamethasone and triamcinolone do not.
So, if a steroid is given just before the test, dexamethasone is slightly less of a concern. Other short-acting glucocorticoids (such as prednisone) should be withheld for 12–24 hours before the test. Longer-acting glucocorticoids, such as methylprednisolone acetate, should be withheld for at least 4 weeks before the test to avoid cross-reactivity.
The administration of glucocorticoids decreases endogenous ACTH concentrations, which causes atrophy of the adrenal cortex. A blunted response to the ACTH stimulation test is expected in patients that have received glucocorticoids (oral, parenteral, or topical) within about a month of the test or longer in case of longer-acting glucocorticoids.
In short – If a suspect Addisonian patient is given a one-off dexamethasone, the ACTH stimulation can be performed, because dexamethasone does not cross-react on the cortisol assay and one dose would not cause complete suppression of the cortisol levels. One dose of dexamethasone may slightly decrease adrenal cortex response to ACTH stimulation.
However, this suppression is likely small and will not affect the ability of the test to diagnose or rule out hypoadrenocorticism.Hope that helps!
Scott 🙂
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