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Blood borne Parasitic problems in dogs
New Information on Tick and Vector Borne Diseases
Ehrlichiosis in Borzoi
Chronic Ehrlichiosis - bone marrow suppression
Leishmaniasis - identifying vector in US outbreak
Babesiosis, anemia and a tumor in Giant Schnauzer
Ehrlichiosis in Rhodesian Ridgeback
Ehrlichiosis and Rocky Mountain Spotted Fever
Ehrlichia
Leishmaniasis and Ehrlichia
Ehrlichiosis
Ehrlichia
Also see Bleeding disorders
also see Parasites
also see Lyme Disease
also see Ehrlichia
New Information on Tick and Vector Borne Diseases
The ability to do DNA testing has led to the discovery of new tick borne diseases and the recognition that many of the older diseases have been classified incorrectly or have more ability to cause disease than was previously recognized. Information in this field is changing fast and it is sometimes hard just to keep up with the name changes. This is a brief overview to help you keep up with the changes if you find yourself searching for information on one of these diseases.
Feline hemobartonellosis is now called feline homotrophic mycoplasmosis (FHM). If your veterinarian is as old as I am, he or she might refer to this disease as feline infectious anemia. This is a disease which causes anemia in cats and is thought to be spread by insect vectors and bite wounds, although it is unclear how big a role each of these plays in the transmission of the disease. There are two different strains of this organism, one of which is now referred to as Mycpolasma haemofelis and the other is in the process of being renamed but will probably be Mycoplasma haemominutum. There is a third organism, Mycoplasma haemocanis, which causes similar disease in dogs, although much less commonly than in cats. These organisms all try to live in red blood cells, leading to immune destruction of the cells in an attempt to kill the parasite. Traditionally this disease has been diagnosed by recognizing the organism in blood smears but this test is pretty unreliable.
At the present time there is a new test using polymerase chain technology (PCR testing) that can more accurately detect this disease. Treatment for FHM usually consists of administration of doxycycline for 2 to 3 weeks. If necessary, it is acceptable to give prednisone or other corticosteroids to control the immune response while the antibiotic has time to work. In most cases treatment will control clinical signs but it is unclear whether it is possible to totally eliminate the organisms and recurrence of disease has been documented.
American canine hepatozoonosis is a relatively newly recognized tick borne disease caused by the organism Hepatozoon americanum, carried by a type of tick, Amblyomma maculatum, which is commonly referred to as the Gulf Coast tick. As you can imagine based on the name, this is a disease found in Southern states. This disease causes severe illness characterized by fever, pain, lameness and accumulation of mucopurulent material around the eyelids. White blood cell counts can be very high and anemia may be present. Changes in bone and other organs are sometimes seen. A related disease caused by Hepatozoon canis, recognized more widely in Europe, Asia and Africa, causes less severe symptoms in most dogs, consisting of fever and sometimes anemia. Diagnosis has been most accurate through muscle biopsies but Oklahoma State University has developed a blood test (serology) for this disease. (Vincent-Johnson NA, 2003). Treatment for this disease currently requires using a combination of antibiotics (trimethoprim-sulfa, clindamycin and pryimethamine) and long term use of decoquinate (Deccoxx Rx) to control relapses. With aggressive therapy there is a fairly good prognosis for long term control of this disease. If your dog has a real mystery disease with some or all of these symptoms, it may be worth asking your vet to check for this disease.
There is a saying at sporting events, "You can't tell the players without a scorecard". This seems to hold true for several organisms previously classified as members of the Ehrlichia family, which was formally part of the rickettsial disease family but now is considered to be part of the Anaplasmataceae family. Since these diseases occur all over the world, it is probably easiest just to list the reclassified names of several ex-members of the family to aid in searches for information on these diseases. Ehrlichia equi is now Anaplasma phagocytophilia. Ehrlichia platys is now Anaplasma platys. Ehrlichia risticii is now Neorickettsia risticii. Salmon disease, which occurs in the Northwest U.S. is now thought to be caused by Neorickettsia helminthoeca. Ehrlichia canis, Ehrlichia chaffeensis and Ehrlichia ewingii all got to keep their names. While this family of organisms has mostly been associated with disease in dogs, cats can develop diarrhea due to Neorickettsia risticii and an unclassified Ehrlichia organism has been isolated from several sick cats.
Keeping pets away from ticks is the best plan but is often impractical. Tick control in the environment outside of a kennel or small yard is pretty difficult so for most pets tick prevention will depend on using a good preventative. As we discover more tick diseases and new manifestations of older tick borne diseases it is becoming increasingly clear to me that good tick control might eliminate a number of the mystery diseases that sometimes occur in dogs and cats.
Dr Mike Richards, DVM
03/02/2004
Question: Dr. Richards,
I'm a new subscriber, and looking forward to learning more.
My 3 1/2 year old borzoi bitch was diagnosed with ehrlichia at the age of 11
months. Actually my vet at the time tentatively diagnosed it as one of the
rickettsial diseases; ehrlichia wasn't that well recognized then, or as common
in Israel as it is now. She was treated with tetracycline, and seemed to
recover. No real follow up was done - the vet didn't know and I hadn't yet
learned enough to ask for a follow up titer and blood test.A year and a half ago she showed signs of neck pains, the vet (same vet still)
thought it might be wobblers syndrome or CVI, and referred me to a veterinary
neurologist. At that point I started reading, found a reference to neck pain
being a sign of ehrlichia, and went to a different vet. Titers were high
positive for ehrlichiosis and there was thrombocytopenia, she was put on a
course of doxycycline which improved her blood chemistry. 6 months later her
titers were still high but the blood chem was fine - and since titers can stay
high for up to a year the new vet wasn't worried. 6 months later a new vet (we
moved) did a blood chemistry, saying that titers could stay high for years and
that once a dog tested positive there was little meaning in future positives.
The blood showed some very mild low platelet levels (185), though the lab said
that the platelets had clustered and that actual levels were estimated much
higher. Hemoconcentration was also high, although this is somewhat normal for
sighthounds, as far as I know. There was also mild neutropenia. Based on these
findings, the vet prescribed another course of doxycycline - she just finished
6 weeks. The new blood chem just came back, and there was very little change.
She is feeling fine, and although she is a really lazy couch potato - common
for borzois, has plenty of energy when she feels like it.After this very long history, here are the questions:
What does this picture mean to you? Is the ehrlichia still there, or could
these be somewhat normal values for this particular dog? What is your opinion
of the value of a titer for ehrlichia? If we do one now and it is low - great.
But what would be the suggested course if it is still high? What is the
significance of neutropenia?The more I read about ehrlichia the more confused I am, since so much of it
seems to be contradictory.thanks in advance for your input! Marcia
Answer: Marcia-
I do not deal personally with many cases of ehrlichiosis, so what I am
going to relate is my understanding of ehrlichiosis based mostly on
literature references. I definitely understand your feeling that this
disease is confusing because there are disagreements in the literature
sources, because a full understanding of ehrlichiosis has not been
achieved yet.In reviewing abstracts of articles on ehrlichiosis that I could find on the
PubMed web site and veterinary databases, there seem to be some trends that
might help in your interpretation of what is happening.* Doxycycline is still considered to be the most effective medication for
treatment of ehrlichiosis but it does not work in all cases. A rough
estimate of the failure rate based on several conflicting studies is
somewhere between 25 and 40% of dogs treated. Other medications that may be
sucessful include tetracycline, chloramphenical, imidocarb and
fluoroquinolones such as enrofloxacin (Baytril Rx). Some studies have
suggested that imidocarb and fluoroquinolones are as effective as
doxycycline and some suggest they are not nearly as effective. I think it
would be reasonable to try another medication if clinical signs returned,
though.* When it can be reasonably shown that ehrlichia organisms are very
signficantly depressed or no longer present, using tests as Western
blot, polymerase chain reaction (PCR) testing or negative blood cultures,
titers tend to drop significantly, although a measurable titer may persist
for long periods of time. I do not know how to arrange for these tests so
it wouldn't surprise me if many other general practitioners don't know,
either. So you may have to talk your vet into talking to an expert in this
field. In the reference search suggestion below, Dr. Waner is from Isreal,
so it may be possible for your vet to confer with him or her.*In several studies, platelet counts returning to normal levels was a
positive sign for response to therapy that correlated pretty well with
other testing.* It is not unusual for dogs to have more than one ehrlichia organism,
another tick borne disease or even an organism that cross reacts on
ehrlichia titer testing that may be confusing when interpreting titers or
response to therapy.* Dogs that have had ehrlichiosis do not appear to be immune to new
infections, even when they have positive titers to the organism at the time
of a new exposure. Either that, or chronic infection is being mistaken for
new infections. I am not sure that it is possible to be certain which is
happening at this time but at the literature references favor the
susceptibility to new infections theory as far as I can tell.If the titers did drop within a couple of months after treatment it would
be a good sign. If not, I would continue to be a little worried about the
possibility of a chronic infection. That would also hold true if platelet
counts continued to be low normal on future (and non-clumped) samples. It
is probably a good idea to check platelet counts for a couple of months.You can find much of this information by searching the PubMed website
http://www.ncbi.nlm.nih.gov, and using "Waner T" as the search term, then
clicking on the related articles links. You might want to do this and
consider printing out some of the research. It may be that your vet can
arrange for one of the other testing procedures if you find yourself
continuing to question the response to therapy based on clinical or
laboratory signs (low platelet counts, continued high titers).Mike Richards, DVM
5/22/2001
Chronic ehrlichiosis - bone marrow suppression
Question: Dear Dr Richards,
I am a new subscriber to the Vet Info Digest. I've often read your excellent information on the
Web when researching for information for my pets, namely for my dog who has ehrlichiosis.Balzac is an eight-year old mix of Black Labrador and Great Dane who was born here in
Montreal, Canada. I adopted him from the SPCA when he was three months old. I brought him
along to live with me when I moved to Mexico about when he was nine months old. We lived
down there for about 4 years and then moved back to Montreal. Last summer, during a routine
heartworm blood test to determine if he still had the disease, (he had tested positive the summer
before)- (and was negative this summer after 12 months of treatment with Heartguard), we found
out that his white and red blood cell counts were below normal and subsequent testing revealed
that he had ehrlichiosis, which he probably caught in Mexico, where there are many ticks and
where this disease is rapidly becoming endemic. In fact, the other dog that I had at the time that I
lived in Mexico had caught the disease while we were living down there, so I was familiar with it.However, contrary to my other smaller older dog, who was abruptly assaulted by this disease
literally overnight, starting with diarrhea, gradual loss of appetite, trembling of the head and loss of
usage of the hind legs, all this within about 2 weeks, and who was completely cured within two
months, Balzac seems to have well surmounted the initial acute phase without symptoms and went
on to the chronic phase without us really noticing anything. He was getting older and has a bit of
arthrosis in his hips, which we thought accounted for the gradual loss of energy, playfulness and
mobility he was experiencing. But after the diagnosis, we realized that it was the ehrlichiosis that
was making him sick.In mid-August, he initially tested positive for ehrlichia canis at 1/20 or greater - the end-point titer
was positive up to 1/1600. Less than 2 months later his titer was at 1/10240, which shows that his
immune system really kicked in. He was treated starting in August, upon the recommendation of a
friend who is a neurological vet and with the agreement of my own vet, for eight weeks with 500
mg/day of Doxycycline. I was told it was useless to repeat the end titer test for at least six to eight
months, because the titer would not go down until then. We did however, continue to monitor his
red and white blood cell count - the red count went back to normal but the white is still down a
little. In conjunction with the Doxycycline, we started him on ADEKs multi-vitamins with zinc daily
as well as 500 mg of glucosamine and 400 mg of chondroitine which he still takes now.He seems to have regained his health, he is now completely transformed - energetic and happy, he
runs and plays again, eats and sleeps well. His white blood cell count however, remains a little low
and that bothers me. My vet does not know why - ehrlichiosis is not a very-well known disease in
Canada - and we don't quite know what to do about it, if anything.I understand that Balzac's remission may be temporary and that the ehrlichiosis may come back, in
which case he will immediately be put back on Doxycycline. Now that I know the symptoms, I
will notice it more easily.I would like to know what you think of this case, if you have ever seen anything like it, what you
think of the low white blood cell count and what recommendations you may have.Any information that may contribute to the well-being of my beloved dog will be greatly
appreciated. Thank you so much for your time and attention.
Sincerely yours, FranceAnswer: France-
According to "The Textbook of Veterinary Internal Medicine, 5th Ed." by Ettinger and Feldman, it
can take up to a year for the bone marrow to recover after a patient with chronic ehrlichiosis is
treated for the disease. The reason that bone marrow suppression persists for so long has not been
determined. If I interpreted the information in this reference correctly, giving doxycycline on a
continuous basis to try to speed up the recovery process (or to try to ensure death of the organisms)
actually slows down the recovery process in the bone marrow, so even though it is hard to wait
around and see what happens, that is actually the best approach. While doing this it probably is a
good idea to be very vigilant for signs of illness, since the depressed white blood cell counts, platelet
counts or red blood cell counts (all are possible) could make it easier for other diseases to occur.I do not see a great number of cases of ehrlichiosis but we have seen occasional patients with this
condition. So far, I can't recall a patient with a recurrence of the illness, perhaps because we do not
practice in an area in which the odds of reinfection are high. If that is the reason, then I would think
that you also have a really good chance of never seeing a recurrence of the illness in Balzac, since
reinfection isn't too likely where you live, either. There are reports of dogs who do not totally
respond to therapy for ehrlichiosis but whether this means they are chronically infected or that their
bone marrow or immune system has been permanently damaged is unclear. Our experience,
although it is with a small number of patients, suggests that a recurrence of clinical signs is not very
likely once patients are treated.Good luck with this. I would be very hopeful that you will see a complete clinical recovery, including
a return to normal white blood cell counts but it may take more time. It is good to keep track of this
recovery. Patients in which the Ehrlichia canis or E. chafeensis organisms are eliminated usually have
dramatic reductions in the titer, or no measurable titer, after six to eight months. It will be reassuring
if you get a good result when you do recheck the titers.Mike Richards, DVM
2/19/2001
Identifying vector for leishmaniasis in US outbreak
Question: Dear Dr Mike,
First let me tell you that my pup that had
Erhlichiosis is doing great now with a normal range
platelet count like you suggested. Thanks so much for
the advice.I am returning to the US in April and I wondered what
the latest information is on Leishmaniasis in the US.Here in Europe there is a collar called Scalibor (like
a flea/tick collar) that is used to repel the sand
flies that transmit the disease here. It is made by
Hoechst and the active ingredient is Deltametrina.
It is tested 97% effective.I wondered if the sand fly is the vector in the US?
Or are they still trying to assess that fact? There
are sand flies in the US though?Also here in Italy local vets are suspicious that it
is possible for dogs to get CanL (Leishmaniasis) by
eating horse manure and I am wondering if that is the
transmitter in the US since many of the cases have
been hunting fox hounds who have contact with horses.I would appreciate an update on this disease and your
views. Also can you tell me what states are having
problems currently.Thank you very much. Regards, Kim
Answer: Kim-
At the present time there is still an ongoing effort to identify the vector
for leishmaniasis in the outbreak affecting primarily foxhounds in the
United States. There are sand flies in the United States but there doesn't
seem to be proof that any of the species here are vectors for
leishmaniasis. Some researchers have questioned whether a vector is even
involved in the current leishmaniasis problem among foxhounds because it
has been shown that direct dog to dog transmission is possible through
abraded skin. The way that foxhounds are housed in kennels, travel as a
group in confined spaces and hunt in packs seems to make the potential for
contact transmission higher in hunting dogs than in housepets.I couldn't find any information on the transmission of leishmaniasis
through horse manure.Leishmaniasis remains a rare problem in the United States. If your dogs did
not pick up this infection prior to the time they come to the U.S. they
almost certainly won't get it here.Mike Richards, DVM
2/14/2001
Babesiosis, anemia, and a tumor in Giant Schnauzer
Question: We have a 6 1/2 year old Giant Schnauzer. He has a mass on the underside of his left front paw at the base of a toenail. He has had a similar mass once previously. At that time it was removed and tested
and found to be a fibrous mass and it was benign. His apetite seems normal, there is no evidence of
blood in stools or urine. He seems to have nearly his normal energy level. We were about to have this
current mass removed as before hoping for a similar result.
Pre-operative testing indicated a low red blood cell count and low platelet count. Our vet did not
want to operate until we find the source of the blood count problem since she believes it is a
separate issue and not related to the toenail mass. A number of tests have been done including a
full SMA, tick titers, tests for brucellosis, xrays and an ultrasound. Test for auto-immune disease
was negative. So far we have found nothing except on the tick titers. Rocky mountain spotted
fever=negative, erlichiosis=negative, lyme disease=positive. Our veterinarian said he doesn't have
any profound symptoms of Lyme disease, but he has definitely been exposed to it. A friend
suggested that it might be "babesiosis" which she said frequently happens along with Lyme disease
infection. We will have to ask our veterinarian if they tested for this, it wasn't mentioned. We are
getting very anxious about getting the mass on the base of the toe nail removed. We are worried
about losing this wonderful friend.Is there a likelihood that babesiosis could be the problem?
If so, what is the treatment or cure?
What drugs or antibiotics would help?
Are there any specific foods that we should be giving him?
He is now taking a 21 day couse of antibiotics for the Lyme disease exposure(doxycycline). Will
that help or hurt his condition if babesiosis is the problem?
Any information will be very much appreciated. We dearly love this gentle giant and we are very
worried about him.
Thank you in advance for your help.
Answer: Frank-
It is possible that the anemia could be related to the mass itself, especially if it is a malignant tumor
such as a melanoma. It is also possible that there is a second problem leading to the anemia. An
important differentiating factor between anemia from chronic illness and anemia from babesiosis or
other infectious organisms is that the presence of immature red blood cells in a blood smear. These
are referred to as reticulocytes. If there are a high number of reticulocytes in the blood smear, then
the body is attempting to respond to the anemia. This is typically what happens when babesisosis or
ehrlichiosis is present. If there are few reticulocytes, or no reticulocytes, then it is more likely that the
anemia is the result of a tumor or some other chronic illness. Since you and your vet have tested for
a wide variety of possible underlying illnesses, I would have to worry about the possibility that the
tumor is the cause.Your vet may have already determined whether or not the anemia is regenerative. It would be
worthwhile to ask. Babesiosis is tested for by examining blood smears for the organism itself, which
lives inside of red blood cells. It is usually present in blood smears when it is causing problems.
There is a serologic test, as well. A positive titer would not necessarily indicate active disease,
though. The treatment for babesiosis is imidocarb diproprionate (Imizol Rx) which was approved for
use in the United States within the last couple of years. As far as I know, there are no commonly
used antibiotics which are effective agains this organism.If the anemia is not regenerative, I think that I would want to look for metastases of a tumor in the
lungs with X-rays. If I didn't find evidence for metastasis I would want to remove the tumor unless
the red blood cell count was low enough that I really thought the patient might die during the surgery.
Your vet may have different experiences than I have had, prompting the more cautious approach (or
the anemia might be regenerative, which would also signal a different cause for it).I hope that things have already improved and you have been able to deal with the tumor. If not, it
may be worth checking to see whether the anemia is regenerative and whether Babesia organisms
are visible in the blood smears and then pursuing whatever course of action seemed appropriate.Mike Richards, DVM
1/15/2001
Ehrlichiosis in Rhodesian Ridgeback
Question: Dear Dr. Mike,
Thank you so much for this wonderful service. I am US
military serving overseas and it is often difficult to
obtain veterinary advice.My 6 month old Rhodesian has tested positive for
Ehrlichiosis (Elisa test). We put him on Doxycycline
but I am worried that his platelet count is not
improving.His count before treating with Doxy was 174, after two
weeks of treatment 168 and now after three weeks of
treatment it is 146.Is it possible that the dosage is not high enough to
fight the disease? Or is this normal for this
particular tick borne disease.Any advise would be welcome.
Thank you.
Regards, Kim
Answer: Kim-
The platelet counts that you are seeing in the test results are within the
normal range for dogs, so it is possible that this is the level of platelet
production that your dog normally achieves. It is definitely a high enough
platelet count to produce expected blood clotting effects, as long as the
platelets are functioning properly (usually there is no problem with this
in ehrlichiosis).It is possible that some platelet destruction is occurring and that you are
seeing rises in the platelet levels by now. It wouldn't worry me, at all,
if a patient of mine continued to have platelet numbers in this range, though.Hope this helps.
Mike Richards, DVM
11/26/2000
Ehrlichiosis and Rocky Mountain Spotted Fever
Question: Dear Dr. Mike,
First, you have a very nice site and do the animal owners a service. Having
just discovered your site while searching for information, I am happy to
subscribe both to support your efforts as well as to give me the opportunity
to ask a question of you.I have read all the information I could find on your site concerning
Erlichiosis and Rocky Mountain Spotted Fever, so I am hopeful that perhaps you
can add to what you have already published.I live back in the Tennessee woods, and although I have always used Frontline
on my dogs, I usually skip January and February, and this year (to my
everlasting shame), I was too preoccupied with my work schedule to go by my
vet's office and hence ended up missing March as well. Apparently, a big
mistake. I have a very athletic 4-1/2 year old SchH III German Shepherd bitch
who competed in the DVG Nationals last year and who has earned a spot this
year as well. Since I had her hips & elbows OFA'd before I bred her in
January, and since she has never had any joint pains (not even "pano"), I was
dumbfounded to see her limping a week ago after just a brief workout.
(Because she had nine puppykins, this was the first time I had worked her
since early February.) Headed straight to my vet. He examined her
and re-Xrayed and saw nothing. So, knowing this was a big deal to me, he
started digging. The titers for Erlichiosis and Rocky Mountain Spotted Fever
were 1:80 and 1:128, respectively, and he stated that this particular test
(??) was to be interpreted as positive for titers less than 1:40 and 1:64,
respectively. He started her on Doxycycline immediately, and she's still
taking it.Now the questions. The more I try to learn about this disease, the more
conflicting information I find, so I hope you can offer some clarifications.
Since, in her case, we believe we caught the disease early on, can you give
any odds for a complete recovery?? (My vet would only say that if the titers,
when repeated in 6 weeks, were negative, that she _likely_ would be cured, but
there was a possibility that it would end her working career.) Can you offer
any more definitive/quantitative assessment of the likely outcome? Is there
any additional treatment that would improve the odds?Second, this was only her second litter, and I had planned to breed her two
or three more times over the next few years as she has produced some very
nice pups. If she does not recover fully and I have to retire her from
competition (which would kill her as much as me -- she loves to work),
would it likely stress her system too much or cause her pain to breed her
again in the future? If not, is there any possibility that the puppies would
be affected in any way?I appreciate any "enlightenment" you can share.
Thanks & regards,
RichardAnswer: Richard-
The current information on ehrlichiosis is that any positive titer at all
should be considered as sufficient evidence to treat for this particular
disease if there are clinical signs and known exposure to ticks. Doxycyline
is the drug of choice at the current time. There is a great deal of
controversy over whether or not dogs are completely cleared of this
organism so it is not surprising that you are confused. The titer to the
infection may stay high for years after an exposure and some dogs have
persistently high titers who have never shown signs of clinical illness.
The assumption in these cases is that the dog probably had a good immune
response to the rickettsia that causes ehrlichiosis and did not need
treatment. Some dogs respond well to treatment initially and then have
relapses that really do appear to be due to recurrences of the
ehrlichiosis and the assumption is that they were never completely
cleared. However, most dogs that show clinical signs will respond to
doxycycline and will not have chronic long term joint damage, as is
sometimes seen with Lyme disease. So basically, your vet has given you the
best possible answer with the information available at this time. There is
some hope that in the future PCR testing or some other form of identifying
low numbers of ehrlichia organisms will allow us to differentiate the dogs
that have almost been cured from the ones that have been cured. I don't
think you can count on the titer to this disease disappearing any time soon
but I would not overly worried about this ending her competitive career,
since high titers persist in a lot of normal acting dogs. If there is
clinical disease due to Ehrlichia, the earlier it is treated, the better.
Early treatment resolves clinical signs more effectively than later
treatment and may reduce the potential for long term infection.Rocky Mountain spotted fever (RMSF) is even harder to draw conclusions
about based on titers. I am somewhat convinced that anytime I want a
diagnosis for a patient when I am struggling to find one that I can run
RMSF titers and get a positive result. The situation probably isn't that
bad but we get a lot of positive titers in situations in which we are not
certain that the results are accurate. On the other hand, when there are
clinical symptoms, when tick exposure is certain, or likely, and when there
are titers greater than 1:64, we will treat for this disease. Doxycycline
is also a good choice for RMSF, so we don't have to know which tick disease
is present, for sure. I have a couple of patients that I have treated for
reasonably certain cases of RMSF who had residual soreness or lameness for
several months, so I think it is conceivable that it does some damage to
the joints, although I have not been able to document this with X-rays.
Most dogs seem to do fine after a few weeks to a few months, though.Some of the more recent work on tick borne illnesses suggests that multiple
infections are very likely to be present, so it is entirely possible that
your dog could have both conditions or could have been exposed to both
organisms.I do not know of any additional therapy, except perhaps the use of
anti-inflammatory medications to lessen the effects on the joints, if
lameness seems to be persisting.I would also consider the possibility that this is all just a red
herring. Titers to tick borne diseases are present in a lot of dogs
without any clinical signs, making interpretation of these titers
difficult, as you have discovered. The most common problem leading to rear
leg lameness in German shepherds that do not have hip dysplasia or cruciate
ligament degeneration is probably intervertebral disc disease. This may
present as an intermittent weakness or lameness, in some cases. If the
lameness persists, it would be worthwhile to continue to try to rule out
alternative problems. Especially since ehrlichiosis is usually associated
with polyarthritis (affecting more than one limb) and since other signs,
such as platelet deficiency, are very common with this infection and do not
appear to have been a problem.If she continues to be lame, breeding could cause problems, as the weight
gain is hard with almost any orthopedic condition. Some bitches who have
had ehrlichiosis will have future problems with breeding, including
difficulty conceiving, abortion or death of puppies shortly after birth. I
could not find any indication of how likely these effects are, though.
Presumably they would be more likely in dogs with chronic illness
(intermittent weight lossI know this didn't clarify things, much. If you have additional
information that you would like to ask about please feel free to write again.Mike Richards, DVM
5/4/2000
Ehrlichiosis is caused by the rickettsial organism Ehrlichia canis. Other examples of rickettsial organisms are Riskettsia rickettsi, which causes Rocky Mountain Spotted Fever and Ehrlichia risticii, which causes Potomac Fever in horses. These organisms tend to be carried by ticks and other insect vectors, in some cases. For ehrlichiosis, the most common vector is the brown dog tick. For this reason, ehrlichiosis occurs anywhere this tick occurs. At present, it has been reported in 34 states, with the northern states being spared in most instances. The southeastern and south central states are the most heavily affected. A few cases of Ehrlichia canis infection have been reported in people after tick bites.
Ehrlichia infection can cause a number of clinical signs. It can be extremely hard to diagnose due to the wide range of symptoms that can occur. Most dogs infected with this organism will have be lethargic, lose weight, show less interest in food and become anemic. Other possible clinical signs include hemorrhages under the skin or in around the gums, swollen lymph nodes, muscular or joint soreness, nasal discharges or nosebleeds, severe neck or back pain, blood in the urine and eye problems ranging from exudates to severe inflammation of the internal eye structures. Neurologic signs such as seizures and difficulty walking can occur. Respiratory or heart related signs can occur due to hemorrhaging and compensation for anemia if it becomes severe. Hemorrhaging occurs primarily due to decrease in platelet counts from the infection. While most dogs show a number of symptoms when first infected with Ehrlichia, there is also a chronic infection that can occur if the acute infection is not treated. In this case, the dog may appear to be normal or may show vague signs of illness occasionally. This is one cause of the complaint that "my dog just isn't doing right". The chronic illness can suddenly become very severe again if the dog is stressed in some manner or become less immune competent for some reason.
The best method of diagnosing this disease is through testing of serum from the dog using an immunofluorescent antibody (IFA) test. Unfortunately, a positive test only indicates exposure. Still, in the presence of clinical signs or if the titer rises after treatment or stays consistently high, infection is strongly implied by the lab results.
Ehrlichia canis is normally susceptible to treatment with tetracycline antibiotics, including doxycycline. In some situations the organism will not respond to these antibiotics or their use is contraindicated due to the young age of a dog or pregnancy. In this case, chloramphenicol can be used and there is anecdotal evidence of success using cephalosporin antibiotics. The bleeding tendencies in this disease are related to a drop in platelets (thrombocytopenia) so it can be necessary to use corticosteroids to treat this condition if the platelet counts are low. While this can be life saving, the use of corticosteroids should be discontinued as quickly as possible so that their immunosuppressive effect does not interfere with successful treatment. Extensive supportive care, including intravenous fluids, administration of blood products and hospitalization may be necessary to treat this problem in some dogs. The survival rate is good if the disease is recognized and treated aggressively.
Mike Richards, DVM
Q: Hi Dr., our dog may have a severe case of Ehrlichia Canis, our vet says. However, most of the symptons described in the Q+A do not really show. Is nose-bleeding a symptom? She has had this a couple of times recently, and it was extremely hard to stop. She also may be possibly infected with Lichmaniosis (SP?), a disease that comes from a meditarrenean sand-fly. (she spent the first 4 months of her life in Portugal)? Are there any experiences as to the cross-reactions or interactions between Ehrlichia and Lichmaniosis? Thanks, Klaus
A: Klaus - I am sorry for the delay in replying. I practice in an area in which leishmaniasis is not a problem and I was not familiar at all with this problem. This does occur naturally in some areas of the United States (mostly Texas) and it is a problem in the Mediterranean area, as you note. A dog moving to the US from an area in which the infection occurs does have to be considered as a suspect for it when clinical signs are present.
Leishmaniasis is caused by a protozoan in the Leishmania species. Skin disease, polyarthritis (arthritis in multiple joints), mucosal disorders (lumps on tongue, gums, etc), damage to internal organs and possibly bleeding disorders. It is diagnosed by examination of tissues from affected dogs or by serology through antibody titers. I am not sure if there is a consistently effective medical treatment for this condition since there appear to be a lot of semi-effective medications listed in the veterinary literature.
The skin signs seen with this disease include loss of hair, scaling of the skin, ulceration of the skin on the limbs or ears, formation of nodules on the body and sometimes pustules.
Ehrlichiosis causes bleeding disorders and nosebleeds can occur when a dog is infected with this organism. It is usually a good idea to consider using an antibiotic, such as doxycycline, when ehrlichiosis is suspected. I am sure your vet already has done that.
Nose bleeds do sometimes occur with ehrlichiosis.
I could not find any information on dual infections but it is possible that the vet school at Texas A&M University may be able to provide more information on this since the problem occurs in their area, if there is still doubt about the diagnosis or prognosis at this point.
Mike Richards, DVM
Q: I have an Old English Sheepdog that was not diagnosed for 2 years with Ehrlichiosis...she is having a relapse and I am afraid I will lose her...She has been on Doxi and Batril for 2 years but never gets better...her white and red blood cell counts are grim....Any Ideas ??? Please let me know , I love her very much , she is all I have ....
A: Dream- I am sorry for the later reply. We do not practice in a area in which ehrlichiosis is common and therefore do not have much practical experience with this. When doxycycline doesn't work, imidocarb dipropionate is sometimes recommended as an alternative. I do not know if it is possible to obtain imidocarb in the United States, though. If doxycycline is controlling the Ehrlichia organisms but the anemia continues to be non-responsive corticosteroids are supposed to be beneficial in some cases, or other immunosuppressive medications may be used. Blood transfusion are sometimes necessary in acute ehrlichiosis and it doesn't seem like they would be ruled out by the chronic nature of the problem you are seeing but they do have a short term benefit and would not probably be a good long term solution to the anemia and low white blood cell counts you are seeing.
I hope that this situation has been resolved successfully by now.
Mike Richards, DVM
Q: We have just been informed by our vet that our dog (a black lab mix) has ehrlichea. We found this out because we were having her tested to try to find out the cause of seizures she was having. How successful are the antibiotics usually used to combat this disease? Where can I find out more info on the disease? Any help would be greatly appreciated. Thank you, Glen
A: Glen- Tetracyclines, especially doxycycline, seem to be very effective for ehrlichiosis. Once in a while there is a recurrence of the condition despite apparently successful treatment. I hope this was the cause of the seizuring but suspect that it was not -- you may need to continue to treat that problem separately. Your vet will work with you that, I'm sure.
I'm pretty sure we have information on ehrlichia in our Dog Information area.
Mike Richards, DVM
Last edited 02/18/07
