Dog w/ vomiting, diarrhea? Lethargy, weight loss? Vet stumped? (For JL mbrs)

[Bob Pr.]

Dog w/ vomiting, diarrhea? Lethargy, Appetite & Weight Loss? Vet stumped?

My thanks to Dr. Artzer of KSU's CollVetMed Tchng Hospl who read this version, suggested changes, many of which I've made

Symptoms (in addition to those in the title just above) may also include
hypercalcemia (elevated blood calcium levels), drinking lots of water
(and lots of peeing). The diarrhea may contain blood and stools may be
covered with mucus. These symptoms can suggest many diseases or
causes (e.g., diabetes; eating contaminated food; cancers; parathyroid,
adrenal and/or renal problems, etc.).

IF your vet is unable to find a definite cause by running the usual
tests and definitely cure it, there is the possibility that the cause
may be infestation by a parasitic fluke (the trematode Heterobilharzia
americana or H.A.), which is not detected by the usual, routine fecal
diagnostic tests. Routine tests identify more common varieties of
parasites which have eggs that float. But, since the H.A. eggs are
heavier and do not float, to identify H.A. the fecal material is put
in a saline solution and its sediment is examined microscopically.
Since this trematode (sometimes called a fluke or blood fluke), until
recently, had never been found in more northern states, vets -- even
in Teaching Hospitals like at KSU-CVM -- had no reason to test for H.A.
This trematode was previously found primarily in or near Louisiana and
the mud flats of the Mississippi River and swamps and, very occasionally,
in those other states bordering the Gulf of Mexico.

But diagnosed cases have recently been found in Kansas, Indiana, North
Carolina, Georgia, Tennessee and northern Texas. Undiagnosed and misdiag-
nosed cases will be much larger and occur in more areas. At present, infest-
ations can and will probably occur in the USA anywhere from Texas north to
Kansas (or Nebraska) and all states that are east of that column.
States to the north and west of that area may soon be next.
AND IF you EVER travel/have travelled with your dog into those likely
infested states AND it goes into water or mud, it can become infested.

This microscopic H.A. trematode lives in the mud of swamps and marshes,
rivers and streams. When this trematode comes in contact with a suitable
host -- dogs (& other members of the dog family), raccoons, lynx, rabbits,
nutria are presently known hosts -- it burrows through the skin and migrates
usually to the liver.

(I strongly suspect Puff got infected on our early morning offleash walks
in a nearby nature preserve. This marvellous wildernesss of fields, hills,
and woods is dotted with ponds, sloughs, marshes, and puddles Puff often
likes to jump into.)

After maturing in the liver, these H.A. trematodes migrate to the wall of the small
intestine where they mate and the female lays her eggs. When the eggs mature,
the parasite exits the animal in its fecies. The H.A. eggs open and the trematodes
seek snails as their second host. They metamorphose in the snails into the form
which will invade dogs, raccoons, and the other hosts.

According to one recent JAVMA article (JAVMA = Journal of the Amer. Vet Med Assocn)
less than 2 tenths of 1 percent of dogs are currently diagnosed with this H.A. condition
and, as mentioned, the most commonly used diagnostic procedures (e.g., the flotation
of more common potential parasitic eggs in fecal samples) cannot identify this H.A.
infestation since H.A. eggs are heavier and do not float. It takes the very specific micro-
scopic evaluation of fecies in a saline solution to visually find and identify the H.A. eggs
in the sediment to correctly diagnose an H.A. infestation.

In my Puff's case (a yellow Lab Retriever), she had a day and a half of chronic
vomiting and diarrhea, often with nothing coming out along with a lack of eating.
I took her to K-State's CVM-TH; they've been our usuual vets for all of her life.

Through X-rays and ultrasound, the CVM-TH found a lump on her spleen which has,
according to many journal articles I found online, a 50% probability of being an espec-
ially nasty form of cancer (hemangiosarcoma) with a probable survival of less than a
year even with surgical removal and chemotherapy.

They recommended surgical removal of her spleen and histopathological evaluation of
it. I agreed and while the surgeons were doing the splenectomy, they saw a mass on
her small intestine so they called me for permission to remove it and resection her intest-
ine (which I gave). Histopathology tests came back a week later and identified the
cause of the mass in Puff's intestinal wall as due to H.A. eggs -- which probably were
the cause of her initial vomiting and diarrhea. The lump on her spleen was benign, VERY
fortunately.

Many of the cases of H.A. in dogs at some CVM-THs included in recent JAVMA (J. of Amer.
Vet Med Assocn) published studies of HA have been identified by post-mortem examination;
that is, the dogs' infestation with this parasite had not been identified and treated during its
lifetime because the H.A. trematode was not suspected.

Typical symptoms of H.A. infestation (with % of cases in which it's shown) are:
lethargy (91%),
weight loss (77%),
anorexia (59%),
diarrhea (55%, often with blood traces),
vomiting (% not given),
hypercalcemia (% not given),
polydypsia/polyuria (↑ drinking, ↑ urination, % not given).

IF the KSU-CVM-TH would have tested/examined Puff's fecies for H.A., I would still have elected
Puff's splenectomy because of the great danger of hemangiosarcoma and the possibility that a
biopsy sometimes misses getting samples of a cancerous area. BUT IF there had been positive
identification of H.A. through fecal samples, that might have saved the surgical resectioning of
Puff's small intestine and her recovery from that.

I post this because I'm sure some of our JL Labs will get this HA infestation and/or their
owners will know of other dogs in their area with similar symptoms. The owners need to be
aware of the symptoms because most/many local vets will not be aware that H.A. is in our
environment and its indicative symptoms can so easily mimic many other diseases.
(E.g., please read the e-mail (in this thread, post #4) sent to me from "Larry" in reply to a
warning I sent out to all local Lab owners I know, telling them about Puff's infestation.)
Whenever, wherever, our dogs acquire H.A., I want them to get prompt, early treatment
rather than have a fatal disease unrecognized or revealed only by post-mortem.

UPDATE (June 2nd, 2010)
Puff finished a 10 day course of medicine, Fenbendazole (FBZ), to kill all H.A. in her system;
a fecal sedimentation test 14 days later showed no signs of H.A. eggs; a portion of the fecal
sample is being sent to a laboratory for a more powerful test (see PCR reference below). If
there are any signs of H.A. still present, another course of medicine and retesting will be needed.
And, when we visit the nature preserve, Puff is on-leash whenever we pass tempting mud and
water areas.

UPDATE (June 11, 2010)
The portion of Puff's fecal sample sent for PCR for the more sensitive testing at Texas A&M's GI
Lab came back as positive for the presence of DNA of H.A. So I drove to KSU and picked up
a 10 day supply of FBZ rather than waiting to get it in the mail so it begins tonight. Puff was a
very trim 63 lbs. before her bout with H.A. While at KSU, I weighed her on their digital scales.
Today, even after a couple weeks of "normal" eating, she weighed only 53.8 lbs. -- she's lost
at least 10 lbs. in this whole process --close to 15% of her normal weight.

UPDATE (June 26, 2010)
After 4 days of giving a second round of the FBZ, Puff had diarrhea and stopped eating. So I
e-mailed my vet and she me told to stop giving the FBZ and to feed a bland diet (I/D or chicken
and cooked rice) along with 10 mg Pepcid 2X/day until she returned to normal. After 7 days
of that, her eating and her stools are closer to but still not quite normal.

UPDATE (July 19, 2010)
Puff finished her 3rd round of FBZ and her appetite and stools are returning to normal. After 30
days, a fecal sample from her stools will be sent to Texas A&M for a PCR test.

UPDATE (August 26, 2010)
Our vet at KSU-CVM-TH sent me an e-mail this morning saying that the results of the PCR test
came back and they found NO sign of H.A. DNA in her stool sample. So the ordeal is over. I was
optimistic they would say this since recently her appetite has been much better and she's
even requesting 2nd and sometimes 3rd helpings at her meals (this has never happened
before). She's regained much of the 13+ lbs. (17% of body weight) she'd lost battling this
infestation.

References

PCR - Heterobilharzia americana
Heterobilharzia americana infection in a dog. [J Am Vet Med Assoc. 2002] - PubMed result
Heterobilharzia americana
Heterobilharzia: Liver & Intestinal Parasite of Dogs

[Snowco Labradors]

How awful for Puff and you. I pray the treatment clears this up.

Thank you for sharing this info.

[Sams Mom]

Interesting read. Thanks Bob. I'm sure this will make it to Canada sooner or later..........

[Bob Pr.]

I sent out the above information to all the people who attended our weekly LabFests in Topeka. I just received the following post from a person who used to attend those with 2 Labs. It sounds suspiciously like his Lab died of undiagnosed H.A. infection.

Hi Bob, I haven’t talk to you in quite a while. This e-mail was painful, as we lost Jake about a month ago. The symptoms sound very similar. He was very lethargic, and wouldn’t eat, he had a temperature, and the blood test came back that he was anemic. Our vet said the symptoms look like it could be a blood disease he got from a tick bite, or it could be cancer. We had him on massive doses of anti-biotic, and then some steroids. We were buying liver and fish just for Jake to build up the blood count, but he was not interested in eating. He reminded me of when my dad was dying of Pancreatic cancer, it was almost like “leave me alone to die in peace”. I came home about a week after we started all this medicine, and found him laying in the back yard under his favorite shade tree, and it looks like he had just exploded inside, and everything bleed out thru the rectum. Two days before we took him in the first time, he was chewing up the deck, and eating bark and wood off of our woodpile. He knew something was in his gut, and was trying to scrape it out.

I am going to forward this to my vet, maybe it will help the next time. I wonder if there is a pill they can take to prevent this, like heartworm pills. Sid was in the same mud puddles as Jake, but so far he shows no sign of problems. -- Larry

(FWIW -- There is no pill so far. -- Bob Pr.)

[SarahJN]

Thanks for this info - I'm glad Puff came through.
This is pretty important, as we all know how much labs love water - well, Millie does, until her head goes under