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- Feline Blood and Lymph Conditions and disorders
- Hypercalcemia and elevation in the alanine transferase (ALT)
- Blood acidosis and TCO2 critical levels
Hemolytic Anemia or immune mediated thrombocytopenia
Anemic and vomiting blood- Cat blood types
- Type B Blood
- also see Parasites
- also see Kidney Problems
- also see Bloodwork
- also see Labwork
-
- 8/27/2001
Hypercalcemia in cats and elevation in the alanine transferase (ALT)
Question: Dear Dr. Richards:
First of all, GREAT website and newsletter! I've earned a lot from
you over the years.Since 1997, my husband and I have had one cat with intestinal lymphoma
and two with congestive heart failure, all deceased. In each case, I felt
that, had we been more proactive about pursuing early symptoms, all would
have enjoyed longer lives than they did. We recently adopted a family of
feral cats bringing our fur ball family to a grand total of 12, and, with
the exception of 2 who have some lung scarring caused by a warehouse fire,
all appear to be very healthy and active. All have tested negative for
leukemia and AIDS and all got their requisite vaccinations.On several occasions, however, we noticed that someone had urinated
outside of the litter boxes. We had assumed it was probably a territorial
issue, (all have been neutered and spayed but we ARE talking about 12 cats),
but as Katie had been observed in the area of the last incident and she was
scheduled for her yearly checkup, we decided to have a precautionary
blood test done.Katie is 3-4 years old and her calcium level was 13 mg/dl and ALT was
142 U/L. Although I know these aren't as high as they can get in
cancer-diagnosed felines, my first thought on hearing this was that we
might be dealing with lymphoma again. My vet is going to do another blood
test in a week (that will be 3 weeks from the initial test) and we're all
hoping that the levels were aberrations. If they're not, what would you
suggest we do next, x-rays? Ultrasounds? With both the calcium and liver enzyme
elevated, can it be assumed that the liver would be the most likely
place to start or could other conditions conceivably cause this---hyperthyroid,
parathyroid abnormalities? Am I just being paranoid or would a liver
biopsy be a consideration at this stage? Katie shows absolutely no symptoms
of anything--but I know many animals don't in the initial stages of a
disease like lymphoma.When we lost our Winchester to lymphoma, it broke our
hearts--especially since his doctors thought his early diagnosis and relative good health
gave him a better-than-average chance of beating the disease. Katie has
youth on her side and if we can give her a shot at a longer life, we'll do
anything we can.We'd really appreciate your insights and advice. Thank you! Pat
Answer: Pat-
There are two problems in the lab work reported in your note. The first
is a mild hypercalcemia and the second is the elevation in the ALT value.
It is probably best to look at these as separate problems, at least at
first.
Rechecking the blood work is a good first step, because calcium levels
are probably the least reliable of the blood chemistry tests, at least from
our lab. It isn't unusual at all for us to find a high calcium level that
is never repeated on subsequent testing. It is best, when possible, to
test for ionized calcium levels when hypercalcemia is present, because this
is the active form of calcium in the body and it helps to know if it is
being regulated properly even though total calcium is high.Hypercalcemia in cats does not have quite as strong a link to cancer as
it does in dogs. There are several causes of hypercalcemia in cats,
including metastatic cancer, kidney failure, idiopathic hypercalcemia and primary
hyperparathyroidism. Except for hyperparathyroidism, these conditions
are fairly close to equal causes of hypercalcemia in cats, with cancer and
kidney failure having a slight edge over the idiopathic hypercalcemia,
which is closely tied to the presence of calcium oxalate bladder stones
in cats.Idiopathic hypercalcemia is called that because no one knows for sure
why it is occurring. It seems more common now than in the past and there is
evidence, based on the University of Minnesota's long term collection
of uroliths (stones in the urinary system) that it really is an increasing
problem, rather than just increasing recognition of an old problem. The
best screening test for this problem is probably X-rays of the urinary
tract to look for the presence of bladder stones or stones elsewhere in
the urinary system. This problem may be related to the use of acidifying
diets (used to try to avoid feline lower urinary tract disorder, a different
urinary tract disorder). If a urolith is identified, then treatment can
be aimed towards controlling that problem.Kidney failure in cats is another common cause of high blood calcium
levels. Usually, the lab work would have clear signs of kidney failure,
such as increases in the blood urea nitrogen (BUN) and creatinine
levels. Since that doesn't seem like the case, this is less likely to be the
problem.Hyperparathyroidism is not especially common in cats, but it was the
cause of hypercalcemia in about 6% of the cats in a study of the causes of
hypercalcemia in 71 cats by Savary et. al (2000) from NC State. Testing
for parathyroid hormone levels can help to rule out this problem. Normal or
elevated parathyroid hormone levels in the face of elevated calcium
levels, especially elevated ionized calcium levels, would be a strong
indication that this was the problem. Low serum phosphorous levels are also
expected with primary hyperparathyroidism, although they also occur when
malignant cancers are the cause of the high calcium levels.The two cancers most commonly associated with high calcium levels in
cats are lymphoma and squamous cell carcinoma. It is worthwhile to search
for these cancers if the calcium levels remain high and there is no
evidence to support the previously mentioned differential diagnoses. A good
physical exam is probably the best way to identify squamous cell carcinoma,
although it may require anesthesia to look in some places this cancer frequents,
such as the back of the mouth and the nasal passages. Ultrasound
examination of the intestinal tract, spleen and liver might indicate
the presence of lymphoma and is probably the best screening test.
Rechecking for feline leukemia virus infection would be a good idea if this tumor
remains a suspect, as well. It seems a little strange that there are no
clinical signs that might be linked to lymphoma, though. Many cats have
persistent vomiting or diarrhea with intestinal forms of lymphoma,
weight loss or signs of other problems with other forms. If signs of
gastrointestinal disease do occur it may be helpful to have an
endoscopic examination of the digestive tract and to obtain biopsy samples in this
manner. Lymphoma is sometimes confused with other problems using this
approach, due to the superficial nature of the biopsy samples that can
be obtained, but it is still a reasonable test procedure.The elevation in the alanine transferase (ALT) occurs when there is
damage to liver cells. This can happen for a number of reasons. Medication
reactions, toxins, cancer and hepatic lipidosis are probably among the
most common causes in cats but there are also lots of times when the ALT
rises for no apparent reason and then is normal on testing after a week to a
month or so. In the absence of any recognizable disease it is probably
best to do exactly what your vet advised, recheck the levels after a
reasonable interval and then decide what to do if the ALT remains elevated. If the
cat is not eating well, waiting is not as advisable. In this case, an
effort should be made to rule out hepatic lipidosis as quickly as possible and
to provide adequate energy to prevent its occurrence as a secondary
problem as time goes on.If the ALT does stay elevated, this would be another reason to consider
ultrasound examination, since it is non-invasive and may be useful in
determining what is going on. We tend to do a fine needle aspirate of
the liver to check for hepatic lipidosis, since it can often be recognized
by this test, which is pretty safe for the patient. Then we might do bile
acid response testing or we might elect to refer for other testing, such as
ultrasound exam and ultrasound guided biopsy, as long as blood clotting
it normal. Some pets have persistently elevated ALT values with no
evidence of liver disease by symptoms, physical exam, X-rays or ultrasound exam and
no decrease in liver function on bile acid response testing. It is
reasonable in these pets to monitor ALT (and a serum chemistry panel) on some
reasonable schedule, like every 3 to 6 months, just to be sure that a
disease process doesn't become evident over time.The presence of both hypercalcemia and increase ALT does make the
suspicion of cancer stronger, since it could cause both problems. It wouldn't
surprise me too much if the lab work is normal the next time, though.
It is a little strange to have aberrations in more than one value in a lab
sample but it happens often enough that the conservative approach of
rechecking the values in a patient who seems to feel good makes a lot
of sense. It also seems possible that the hypercalcemia could be the
idiopathic syndrome seen in cats and the ALT rise due to a decrease in
appetite leading to hepatic lipidosis or of some other complication
associated with that condition.I hope that this helps some with your thought process in working
through the possibilities, if the lab values for these two conditions continue
to remain high.Mike Richards, DVM
Blood acidosis and TCO2 critical levels
Question: Hi Dr. Mike,
Just want to tell you how much I have appreciated your web site. It is a great asset to the internet.
I have a 13 year old neutered male kitty named Velcro.
He is a very sweet boy, and has had a rough year and a
half, all of which I will write out in an email in the near
future for your opinion.
However, the immediate problem is that he recently (two days
ago) had a blood test done which showed a
TCO2 (bicarbonate) level of 9 (13-25 normal) and an anion gap
of 33 (13-27 normal). He has been on 10
mg/prednisone a day for several months for a not totally confirmed
benign brain tumor (no MRI--based on
symptoms and other extensive tests--I'd already spent $2700
on him, and just couldn't afford the MRI). I had
tried to reduce it gradually to 5 mg/day, but he appeared to
have a small seizure.
Anyway, he has had sporadic diarrhea for the past month, which
I attempted to treat progressively with
Kaopectate, Imodium AD, and Flagyl, along with some anti-allergy
type canned food from the vet (duck and
venison). His diarrhea only got worse, turning to total
liquid. So the vet prescribed Eukanuba low residue
food, and I am gradually taking him down to 7.5 mg prednisone/day.
My question are these: The vet thinks the acidosis may
be caused by the diarrhea, and I agree. She also
thinks the prednisone may be causing the diarrhea, which is
why we're reducing it (and may again try going
down to 5 mg/day). Is it possible that the prednisone
alone could cause acidosis? Also, how low can TCO2
go before it becomes life threatening? I feel that I may
have to decide if he is going to pass from brain swelling
or acidosis.
Thank you for your help. I will post his full history in
a hopefully somewhat succinct fashion in the next few
days.
Thanks again.
Gayle and sweet Velcro
Answer: Gayle-
A total CO2 level less than 12 mEq/L is considered to be dangerous,
so 9 is definitely in the range in
which acidosis is likely to be a major problem, if it is not an artifactual
value.
The lists of medications that are likely to cause decreased TC02 that
I have seen do not include
prednisone. The medications that seem most likely to cause problems
with this are ammonium
chloride and tetracycline. If there is a delay in measuring the TC02
in a sample, it may falsely
decrease the TC02 of the sample. I can't be certain that prednisone
couldn't cause acidosis but it
must not be a common cause unless I just missed something.
The two causes of low TCO2 that are clinically important are metabolic
acidosis and respiratory
alkalosis. The most common causes of respiratory alkalosis sufficient
to cause a low TC02 are lung
diseases (pneumonia for instance) or pleural effusions. The patient
is usually in obvious respiratory
distress when the disease is sufficient to cause a significant drop
in TCO2, though. Metabolic
acidosis is caused by ketoacidosis from diabetes, urinary blockages,
kidney failure, anti-freeze
poisoning, aspirin toxicity and dehydration (usually has to be severe).
If dehydration was caused by
diarrhea the TCO2 could drop. I am not sure whether diarrhea alone
would cause a significant
acidosis in a patient compensating for the fluid loss since vomiting
usually causes rises in the TCO2
and I haven't seen much written about what diarrhea does.
A small increase in the anion gap in cats is often due to a decrease
in potassium, if it wasn't
compensated for in the formula used. This can occur from diarrhea or
be an early sign of kidney
insufficiency. Decreases in other cations, such as calcium and magnesium
can do this, as well. On
the flip side, increased "normal" anions like lactate, ketoacids, albumin
and phosphate; or really bad
stuff like ethylene glycol (anti-freeze), methanol and salicylates
in the serum can lead to increases in
the anion gap.
The reason for these changes is that the anion gap is a formula that
only includes the major players in
the positive and negative ionic mixture. Several formulas have been
used to calculate the anion gap
-- the two I am familiar with are (Sodium + Potassium) - (Chloride
+ Bicarbonate) OR Sodium
- (Chloride + Bicarbonate). There are other cations and anions
in the serum but these exist in small
quantities (even potassium is small enough to leave out of the one
formula). The anion gap increases
when another anion type chemical is present in large enough quantities
to screw up the formula or
when the cations are low enough to impact on the formula.
Since you have probably been measuring electrolytes as part of lab panels,
it seems unlikely that
diabetes or severe kidney failure would be present and unnoticed, taking
away the most likely
suspects in an elderly cat and I suspect that you would have seen clinical
signs of severe respiratory
disease. So I guess I'd have to go with you and your vet on the
diarrhea as a probable cause. We
do sometimes see patients who have pretty severe diarrhea from prednisone
use. For reasons I can't
explain it sometimes helps to use a different form of corticosteroid,
like dexamethasone or
methylprednisolone. When we absolutely have to use a corticosteroid
and diarrhea is present it
seems to help sometimes to give a little plain yogurt daily or to use
a probiotic preparation and
sometimes we try concurrent antibiotic use with some success.
I hope that you are seeing improvement. Cats and most other species
have tremendous ability to
compensate for acid-base imbalances if they just live through the crises.
Hopefully Velcro is doing
better.
Mike Richards, DVM
2/13/2001
Hemolytic
anemia or immune mediated thrombocytopenia (ITP)
Question: Dear Dr. Mike,
We are new subscribers from the UK to your service and
we have an urgent request for your help and
advice.
Our female cat, Billie, is 9 years old and diagnosed as having
Haemolytic Anaemia 6 weeks
ago. At that time, our local vet prescribed the following:-
1 x Cyclophoshamide every 2 weeks
1 x 5mg Prednisolone twice a day
1 x 50mg Cimetidine twice a day
plus a course of Danazol for 2 weeks.
Billie's condition improved significantly and her red blood cell
count was up to 35. 2 weeks ago, her red
cell count fell to 31 and on Thursday, this week, fell further
to 20.
Our vet advised us that there was nothing further that could
be done but, after much
argument, eventually contacted another Veterinary Hospital in
Cambridge (England) to get
further advice.
Yesterday (Friday 15th), we were given instructions for the following
increased medication:-
3 x 5mg Prednisolone twice a day
2 x 20mg Ronaxan twice a day (although no parasites had been
apparent in blood tests)
1 x 50mg Cimetidine twice a day
1/4 tablet Suralfate (Antepsin) 3 times per day
I requested that Billie be given Danazol or some similar inhibitor
but the vet refused, saying that the drug
will cause liver failure and they were unwilling to prescribe
Danazol again.
Please would you advise me whether you feel that Billie has been
prescribed the correct medication and
whether Danazol would be severely detrimental. Blood tests have
been done every week for 6 weeks but
the vet is unable to find the reason behind Billie's condition.
Five months ago, she received Radio-Iodination treatment for
Hyperthyroidism. Is it possible that this
could be a cause and is it possible that she has parasites in
her blood but that these are being missed, or
not traced, in her blood tests?
Today, Billie is very lethargic - the new increased drug schedule having started yesterday.
Any information or advice you can give will be very much appreciated
as our vet seems to be unfamiliar
with this awful disease.
With many thanks, Michelle
Answer: Michelle-
Hemolytic anemia in cats can be caused by blood parasites and it can
be hard to find
Hemobartonella, the blood parasite seen most commonly in cats, even
when there is a high
degree of suspicion for it. In the U.S., I think the most commonly
recommended antibiotic for
hemobartonellosis would be doxycycline. I am not sure what Ronaxan
is, but if you can supply
a generic name I might be able to give you more information on it.
I think it is reasonable to
treat for the suspicion that hemobartonellosis is present and that
is probably what your vets are
doing.
There are a lot of reports of Danazol (Rx) causing liver problems in
cats. I would be very
reluctant to use it, even though your cat didn't have problems with
the first round of treatment.
Prednisone dosage may need to be as high as 8mg/kg to successfully treat
immune mediated
thrombocytopenia or immune mediated hemolytic anemia in cats, so even
though the dosage of
pred recommended is high, it probably isn't beyond the maximum recommendations
at this
point. The use of protective agents for the GI tract is common
when administering dosages of
prednisone in this range, which is probably the reason for the cimetidine
and sucralfate. In cats
it is usually recommended to push the corticosteroid dosage rather
than switch to other
immunosuppressive agents until it seems certain corticosteroids won't
help, since other
immunosuppressive agents tend to be more toxic in cats than in dogs.
The reason I mentioned immune mediated thrombocytopenia (ITP) is that
your original vet's
treatment plan seemed geared towards that problem, so I am a little
concerned that it may be
the problem rather than hemolytic anemia. If this is the case, a common
cause of platelet
deficiency in cats is bone marrow suppression from feline leukemia
virus (usually) or feline
immunodeficiency virus (less likely).
I have not heard of a correlation between radioactive iodine therapy
for hyperthyroidism and
either ITP or IMHA in cats. I can't say that it couldn't have
contributed to this problem but it
would be unusual, I think.
I hope that the new medication recommendations are helping or will help
soon. If you have
further questions or need clarification of anything in this note, please
feel free to write again.
Mike Richards, DVM
4/18/2000
Q: Our kitty Misha came with our house purchase. We believe he is about 8 years old and he weighs 14 lbs. For the 4 years we have had him, he has been an indoor cat. He is our only cat and since last August, has received 3 treatemtns of Advantage so he doesn't have a problem with fleas. Last week he vomited an hour after his morning meal and the vomit was full of blood, at least a half cup or so. My regular vet referred me to another vet who had an endoscopy machine. The vet looked in his stomach for possible ulceers but didn't find any ulcerations. Given the amount of blood he vomited, he performed exploratory surgery and checked for any blockage in his intestines. He didn't find anything other than a small mass in the secum which when dissolved in water was just grit and blood. The medications given were barium, reglan and carafate. Two days before he was scheduled to have his stitches removed, I came home Wednesday evening to find him weak with his pupils dilated. He had been perfectly active, eating well, etc. up to that night. I rushed him to the vet and when they tested his blood, they found him anemic. The vet guessed the blood was probalby leaving through his stools. He was given blood transfusions on Wednesday night and kept for observation. The chest x-ray is clear, there is no blood in his stool, there is no fluid around his belly area to account for internal bleeding. He was given blood transfusions on Wednesday night and although his count went up, it went down again. The results for feline leukemia are negative. He is now on an IV, prednizone, tagamet, barium and carafate. My regular vet thinks it sounds like an auto-immune disease of sorts. Most of what I have read indicates these diseases show up with time, not suddenly in less than 8 hours. Given that this is a pampered, strictly indoor cat, I cannot imagine how he could have been contaminated by another cat. He has not had any weight loss. What information is known about allergic reacitons to medications that could cause this anemia? One of our friend's mother had something like this due to a stroke medication, Teclid, which caused her to have transfusions for over a month. The Teclid took a long time to leave her system. What are the possibilites that our cat could have an allergy to one of the medicatons he got after the exploratory surgery? Needless to say, like many pet owners feel, he is our baby. Any comments? G.
A: I would be most concerned about a bleeding disorder such as exposure to rat or mouse containing an anti-coagulant in this situation. If this hasn't been ruled out, it would be worth asking your vet about. Liver disease can lead to problems with blood clotting. There are some platelet disorders that affect cats, too. In dogs, heartworm disease can lead to coagulation disorders but I do not know if this is seen in cats with heartworms and that seems unlikely in your cat's case, anyway.
None of the medications you listed are associated with bleeding disorders that I know of but that is a good thought -- all things like this have to be considered.
Auto-immune disease is certainly possible, too. I think your vets probably considered the above possibilities but it doesn't hurt to ask.
I wish I could help more. This is definitely a situation in which you
need "hands on" help.
Mike Richards, DVM
Cats have A, B and AB (rare) blood types. Most cats in the United States have type A blood - something like 99% of domestic shorthair cats have Type A blood. This ratio varies from country to country. Other cat breeds have a much higher incidence of Type B blood. As the popularity of purebred cats increases it is likely that the ratio of cats with Type B blood will also increase.
There is no "universal donor" blood type in cats - a very small amount of the wrong blood type can kill a cat if is is sensitized to the blood. This can be an issue in some cat breeds. In particular, British Shorthair, Cornish Rex and Devon Rex cats, where the percentage of Type B cats is much higher, perhaps as high as 50%. Other breeds with significant percentages of Type B blood include the Abyssinian, Himalayan, Japanese Bobtail, Persian, Somali and Sphinx breeds. (preceding information from Urs Giger, University of Pennsylvania, Kirk's XI).
If a Type B queen (mother cat) gives birth to Type A kittens, severe
reactions can occur in the kittens. Type B cats have strong antibodies
against Type A blood. These antibodies are passed in the milk, which is
very bad for any kittens that are Type A. Since A is the dominant blood
type, this means that most of the kittens born will be Type A when a Type
A father breeds with a Type B mother. Neonatal isoerythrolysis-- destruction
of the kitten's red blood cells by the antibodies in the mother's milk
-- is very likely to occur. In breeds in which significant percentages
of Type B blood occur, it is wise to know in advance what the blood types
of prospective parents are. Your vet can arrange to have blood types tested.
Mike Richards, DVM
Q: I breed Maine Coons and have just found out one of my kittens in a litter has type Bblood. This kitten has been sold as a breeder. Please advise how this happened as I have been unaware of this in my cats in the past. I am not learned on this subject and how would I produce a type B kitten.? Is it possible please to E-mail me also as I will probably never find the answer on this site. Thanks so much. K.
A: Cats with type B blood seem to be more common in purebred lines than in the general population. Cats can be type A, type B, type AB and very rarely type AE. Type A is dominant to AB which is dominant to type B. In order to get a type B cat when no one else is type B it is highly likely that you have bred two type AB cats (or else you have a type B cat you don't know about).
The people planning to breed this kitten in the future will need to
be careful with their breedings. Cats with type B blood form anti-bodies
against both A and AB blood types. Kittens born to these cats who are type
A or AB absorb antibodies against their own blood from the mother when
they nurse for the first time. This causes problems in the kittens ranging
from sudden death to severe illness to less severe problems like loss of
the tips of tails.
Mike Richards, DVM
Last edited 01/30/05
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