Elise's diarrhea thread

alex117

Post   » Thu Sep 02, 2021 3:05 pm


Hi everyone,
The post mortem result has just come back. Below are the results of the post-mortem examination for when you are ready.

On Elisee's post mortem exam, there were several abnormalities. The final diagnosis looks like cancer.

First and most obvious, there was a lot of blood in her chest. I think all the fluid I saw on radiographs was blood, some of which might have clotted prior to death (it would account for the "tissue" I saw with ultrasound). There was a lot of blood in the pericardial sac around the heart, which was likely the immediate cause of her death (ie, pericardial tamponade)

There was a solid white mass inside her heart; it was large, and took up nearly the entire left atrium. I looked at the cells under the microscope, and it looks like a sarcoma (soft tissue tumor, where the cells have a characteristic "spindle-shaped" appearance). This would explain the changes in her heart, as her heart would have been working overtime to make up for the space the mass took up, and over time will lead to heart failure. The mass may have recently grown large enough to partially obstruct the valves in and/or out of the atrium, and was easily large enough to push on other chambers & blood vessels of the heart. The aorta & pulmonic vessels are right in that area. I did not see a direct source of bleeding, but if there was a small tear in the heart or one of those blood vessels, it would absolutely account for the blood in her chest, and can take time to accumulate.

There were several white nodules in her lungs (also sarcoma-looking cells).

Her liver was small & irregular, and there were several white nodules there, too (also sarcoma-looking cells). Liver dysfunction can cause clotting disorders, but it looked like there was still some functional tissue.

The mass in her neck was mostly filled with fluid; some of it was dark-brown, some looked like old unclotted blood. The outer shell was thin & mineralized. This looks like some kind of cyst.

Overall, this looks like cancer. I think the mass in her heart is what led to her heart failure. Hemangiosarcoma (tumor of the blood vessels) usually affects these tissues and usually presents with bleeding, but those tumors typically dark red, not white.

Full Necropsy Report

External exam
--Integument: lice on left (up) side.
--BCS: 2/5

Internal Exam
--Thorax: Large amount unclotted bloody fluid left (up) side of thorax, large amount clotted blood right (down) side. Great vessels appear intact, no lacerations or punctures.
--Cardiovascular: Large amount unclotted blood in pericardial sac, potential pericardial tamponade. Heart large, right ventricular wall thin. Large (~5mm) round firm tan pedunculated mass arising from dorsal inner wall of left atrium/auricle, took up majority of space inside atrium. Cytology: Spindle cells, mild anisocytosis, mild anisokaryosis, ~1 binucleate cell per 3 hpf
--Respiratory: Lungs very small/compressed. Many small black specks throughout parenchyma, 2 small black dots ~2 mm each. 3 round white spherical nodules visible on lung surface; cytology shows combination of homogenous vacuolated epithelial cells & spindle cells.
--Abdominal cavity: wnl
--GI (stomach, intestines, cecum etc.):
--Pancreas: WNL
--Liver: Small, irregular, mottled, pale. Several large (~5mm) white nodules present (tip of right lobe, another near gallbladder). Several small black miliary nodules visible.
--Spleen: WNL
--Urogenital: WNL.
--Nervous system: WNL.
--Musculoskeletal system: WNL
--Mass left ventral neck: ~1.5 cm hard + fluctuant mass. Cranial aspect mineralized, medial pocket of mass filled with translucent black brown fluid, dorsolateral pocket filled with dark nearly black unclotted blood.

Differential diagnosis: Metastatic neoplasia; cytology suspicious for sarcoma. Clinical signs & locations of masses consistent with hemangiosarcoma, but masses look white not red.
Hemothorax: source of bleeding may have been lung mass, left atrial mass, liver failure/coagulopathy. Death may have been cardiac tamponade or blood loss.

Samples saved for histopathology:
heart & lungs, piece of liver, neck mass

User avatar
Lynx
Celebrate!!!

Post   » Thu Sep 02, 2021 9:56 pm


Thank you for taking the time to write this all out and share it with us. It looks like a very detailed examination. It is often so helpful to know the full extent of the medical issues your pet was dealing with. It does sound like there was no way forward that would have saved her.

If you follow through with the histopathology of the samples the vet has collected, let us know what is found, especially if there is confirmation of sarcoma.

A good vet when doing a necropsy generally has an idea of what he/she is looking for and after a gross necropsy, will send specific samples to be examined. This provides a more complete picture of what happened.

I know your loss still hurts.

alex117

Post   » Thu Sep 02, 2021 11:47 pm


Thanks Lynx! Life must move on, I feel like it is also my responsibility to remember this moment and write down everything I could so that other owner can reference this thread in the future.

I am thinking about the need for histopathology, please correct my thought process if I am wrong (i am more than happy to order it if it helps).

The Necropsy report indicates couple of things; 1) Clinical signs & locations of masses consistent with hemangiosarcoma, but masses look white not red, 2) the white mass cells under the microscope looks like sarcoma (Cytology: Spindle cells, mild anisocytosis, mild anisokaryosis, ~1 binucleate cell per 3 hpf). 3) white spherical nodules were seen in Lung, Heart, and liver, so we can also confirm there is Metastatic neoplasia.

Based on that, we are almost sure she has cancer, but we don't know what kind of cell it is (it is likely to be sarcoma). With a further investigation on the histopathology, what we can find out is the specific cell of this cancer, with enough research, we probably can extract the marker of it. I think if Elisee is a human, it may be worth knowing this because it helps the doctor to develop a specific chemotherapy treatment to kill this type of cancer. However, Elisee is a little bean, and just like other guinea pigs, I am not sure chemotherapy treatment is something that their system can tolerate (they may but it is only one single case https://cvm.ncsu.edu/courageous-guinea- ... ts-cancer/). And also, if it is a hemangiosarcoma, even we have a solution to kill the cell, there is no way we can take a biopsy that can confirm it is a sarcoma (well, no way we can biopsy the heart). So I am not sure how useful it can be for other cute piggies.

User avatar
Lynx
Celebrate!!!

Post   » Fri Sep 03, 2021 8:37 am


I do not know enough to say if the biopsy would be useful to other guinea pigs either. In a typical case study, the problem is identified and treatment is given, generally successful to show the way for others whose guinea pigs with similar issues. Unfortunately for you, the extent of the medical issues was only discovered during a necropsy.

Whatever you choose to do, thank you for sharing Elisee's medical information.

p.s. the linked to article discusses surgery to remove a skin cancer of the cheek. The first surgery did not completely remove the margins and a second surgery was required. In my limited experience, it seems skin cancers, if they have not metastasized, can be removed. Your guinea pig's issues were much more extensive. I recall one guinea pig here, Big Boy, who had cancer treatment some years back.

alex117

Post   » Fri Sep 03, 2021 11:36 am


I shared the wrong link, here it is :D
https://www.fox47news.com/neighborhoods ... apy-at-msu

User avatar
Lynx
Celebrate!!!

Post   » Fri Sep 03, 2021 8:09 pm


That is a sweet story. I hope she had a good outcome from the chemotherapy.

alex117

Post   » Sat Sep 04, 2021 3:04 am


I think i will do histopathology on her heart tissue, i will keep you posted :)

User avatar
Lynx
Celebrate!!!

Post   » Sat Sep 04, 2021 8:16 am


I found a link to the lymphoma case I wanted to mention, though it still is not the same as what your guinea pig had. More similar to the link you gave.
https://www.guinealynx.info/records/view ... =123&p=237

alex117

Post   » Sun Oct 17, 2021 7:05 pm


After a month of waiting, i got the report from histopathology

DIAGNOSIS:
1. HEART: MILD, CHRONIC, MULTIFOCAL, LYMPHOCYTIC, HISTIOCYTIC MYOCARDITIS WITH MYOCYTE DEGENERATION
2. ADIPOSE TISSUE (EPICARDIUM): MODERATE, CHRONIC, ATROPHY
CASE COMMENT: Cardiomyopathy is seen occasionally and spontaneously in guinea pigs. The cause is unknown. In this case, there were slightly more inflammatory cells than are typically seen in myocardial degeneration, and an infection is possible. There was no direct evidence of infection in sections of the heart, and it is unknown if this animal had multisystemic lesions. This animal had slight reduction in nutritional status."

This result indicates that Elisee was dealing with a cardiomyopathy, or an abnormality within the muscles of her heart. This can lead to abnormalities in conduction of the electrical impulses that cause her heart to beat and can lead to a buildup of fluid within the lungs when the blood is not able to be pumped appropriately. Heart disease is an ultimately progressive and fatal condition, and based on these findings humane euthanasia was definitely the most kind and compassionate choice for Elisee in her state.

User avatar
Lynx
Celebrate!!!

Post   » Sun Oct 17, 2021 8:37 pm


Thank you for sharing the histopathology report. Necropsies can often be very helpful, giving us a broader view of our pet's medical issues. I agree that humane euthanasia was the most kind and compassionate choice for her.

User avatar
ItsaZoo
Supporter in 2023

Post   » Sun Oct 17, 2021 8:44 pm


I am so sorry you lost Elise. You did so much to make her comfortable and help her have a good life despite her health issues.

Bookfan
For the Love of Pigs

Post   » Mon Oct 18, 2021 10:23 am


I'm sorry you lost your girl. You took great care of her, and on some level I'm sure she knew it

Post Reply