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Hormonal Skin Disorders of Dogs
Hormonal skin problems
Growth
hormone responsive dermatosis
also see Hormonal problems
also see Demodex
Mange
also see Haircoat
problems
also see Hairloss Problems
also see Itching
Problems and Control
also see Pyoderma
also see Sarcoptic Mange
Hormonal Skin problems
Question: Dear Dr Michael,
I wrote you in June to ask for some information regarding my dog Lucky
who
I suspected had some hormonal disturbances after being neutred but
I was
not really happy with your answer since you only gave me advises as
to if
he were suffering from mange or fungal skin problems and he had been
treated for both fungal with griseolfun and ivermectin for demodectic
mange.
Nevertheless, I went to see another doctor since my dog never got
healthier. He agreed that it was very likely that he had
hormonal
disturbances after he was neutred, since all the symptoms were present.
He
has now been treated with hormones for 3 months, (after 1 month treatment
in April with Supertest 0,8 mg injections),the name of the tablets,
Andriol, I do not know the contents since it is not written on
the
medicine, however he has been medicated with one tablet every 3 days
for
2,5 months and is now on maintenance dose once a week.
His condition has
been improving ever since we started the medication. He is now
again on
Ivermectin injections, first once a week 3 times and now once every
second
week. Scraping was done prior to this medication and demodectic
mange was
found present, again, but he did not respond to any medication
before we
started with the hormones, but now it seems to be effective.
I write to you again, because I am a bit worried that he now gets to
much
of hormones, because when he gets the tablet once a week he gets very
tired
just after a short walk to the beach. His conditions improves
within the
week and then fall back when taking the tablet. How will we know
when to
stop the medication or to slow down even further? This is what I really
want to know and also if there is any side effect of the hormones,
like why
he is in such a bad shape and are somewhat lazy? My other dog has been
very
patient with him, but now she seems to think it is enough and
wants him to
come along and play.
He was neutred in January this year and has suffered ever since, with
various skin problems, lack of energy and sometimes high temperature.
When he was neutred he was very healthy, but I had a feeling he had
lots of
hormones, he almost broke down my gate to be able to get to the streets
at
night and his penis emerged if we just padded him a bit, which is also
the
case now. I find this very strange when explaining that
he is actually
neutred and cannot have sex, even though it looks like it.....
I read your newsletter today regarding prednisolon and prednil and for
a
while I gave him treatment for his inflammation, maybe this was totally
wrong? He definitely suffered from kindeyproblem or urinating
problem and
was very very heavy at that time. If I administer prednisolon
now he
immediately reacts with panting and start looses his hair again.
His skin is very dry, I use teethree and oatmeal shampoo for his seborrhea
(which I think it is, the doctor is not very specific in that) and
occasionally treat him with various oils, like lavendel and his coat
will
be more soft and develop better. He also receives a lot of vitamins.
He has still very reddish coat, especially during late afternoon, after
the
walk to the beach.
Do you have an advice to give me?
Answer: Sissel-
The reason that I did not include information on hormonal disturbances
is
that the likelihood of your dog actually having a hormonal disorder
is very
very low. I should have asked you specifically why you thought that
hormonal disease was present, instead of trying to point you in another
direction first. Even though testosterone deficiency sufficient to
cause
skin disease (usually bilaterally symetrical hair loss on the sides
(flanks)), is considered to be very rare I should have answered your
questions concerning the use of testosterone.
I still believe that it is better to concentrate on the demodectic mange
and problems secondary to it, at least until it is eliminated as a
problem.
My best advice on this matter is that it would be better to give ivermectin
daily (orally) until the demodex does not show up in skin scrapings
anymore. Prednisone and other corticosteroids suppress the immune system
and make it hard to cure the demodecosis, so they should not be used,
if
possible, in a dog with demodectic mange.
A lack of androgens (testosterone and similar hormones) is treated most
commonly using methyltestosterone at a dosage of 1mg/kg, up to a maximum
dosage of 30 mg, given every 48 hours until hair grows in on all affected
areas, then trying for a longer dosing interval such as week, if possible.
In many dogs, there will be apparent improvements in hair coat condition,
even when testosterone deficiency is not present, due to the direct
effect
of the testosterone. It sounds like your vet is following the
standard
guidelines for this sort of treatment. If you are seeing adverse effects,
I
honestly think it would be best to stop the treatment and re-evaluate
the
situation but that is a decision best left to you and your vet, who
can
evaluate the skin disease present and the response to hormones ---
both
good and bad -- before making a decision.
Androgen deficiency normally causes approximately equal hair loss or
thinning of the hair on both sides as the primary sign, at least according
to the information that I can find. I do not have personal experience
with
this particular sex hormone problem, so I do not know much more than
this
about it.
Androgen excess, which is a sex hormone dermatosis that is normally
responsive to castration, causing hair loss that starts around the
rear,
gradually spreading to include most of the hair on the trunk and also
causing skin color to darken. Usually dogs with this condition seem
to be
otherwise of normal health.
Neither sex hormone deficiency nor sex hormone excess normally causes
a
predisposition to demodectic mange, as far as I can find in the literature.
However that does not necessarily mean that it is not possible that
this
happened in your puppy's case.
Side effects of testosterone hormones are most commonly behavioral,
usually
including aggressive tendencies but other effects have been reported,
including lethargy and depression. These effects appear to be dose
dependent and decreasing the dosage might be helpful. There have been
reports of liver problems with the use of some of the androgenic steroids
but this is reported to be uncommon.
If your dog has a sex hormone deficiency, it is unusual to be able to
stop
the supplementation of hormones, since the problem usually persists
life long.
My best advice is to continue to treat the demodectic mange, to consider
the possibility of secondary infections, either bacterial or
yeast
infections, affecting the skin. Since it may be hard to definitively
test
for sex hormone deficiency and supplementation may have to be life
long, it
may be worthwhile to consider taking a break from the medication to
see if
it is really necessary. The University of Tennessee runs tests for
sex
hormone levels and it should be possible to mail samples to them from
anywhere, if you and your vet are interested in confirming this condition.
It would be absolutely necessary to stop the hormone supplementation
for
several weeks prior to attempting to run these tests, though.
If the information you are looking for is not in this note, please feel
free to write back for clarification or to ask for additional information.
I was not able to provide much information on the Andriol as that is
not a
brand name, or generic name, that I am familiar with.
Mike Richards, DVM
12/10/2000
Hormonal
skin disease - Growth-hormone responsive dermatosis
Question: I have a 4 year old Irish Setter (neutered).
The breeder had told me if I had him neutered it would ruin his coat and
she was right. His coat has faded from mahogany to orange-red and
gotten very fine and fluffy. Now it is shedding to the extreme and
is very bare. My question is, "Why can't he be given a low dose of
testosterone as a form of hormone?" He only had one testicle to begin
with but had a beautiful coat, very dark, heavy, and shiny. My vet
has told me she would check into, but says she hasn't had any luck in finding
anything out. Would appreciate your help.
Answer: Martha-
I don't think that you can assume that the changes in the hair coat
that you are seeing are due to
neutering. That is possible, but there are other conditions that can
cause signs similar to those that
you are seeing.
Growth-hormone responsive dermatosis causes the symptoms you are seeing.
It usually occurs in
young adult dogs, causes loss of the guard hairs, causing a "puppy
like" coat, which eventually
progresses to the point where there are some areas of hair loss, usually
around the neck and back of
the thighs. The skin in the areas of hair loss may be dark compared
to normal skin. Usually there are
not systemic signs associated with this problem.
Hyperadrenocorticism and hypothyroidism should also be ruled out in
a dog with the symptoms that
yours has. Both of these disorders are unusual in young adult dogs
but have been seen as young as a
year or two of age in some patients. This should be done before trying
to rule in or rule out sex
hormone and growth hormone responsive dermatoses, because if these
conditions are present they
can be diagnosed through lab testing and would interfere with the tests
for growth hormone
responsive dermatoses. If there is any question about whether
this is a hormonal skin disorder, skin
biopsies can help to rule out other conditions.
Sex-hormone responsive dermatosis does occur. Normally, there is hairloss
in the inquinal region
early in sex hormone responsive dermatitis and then hairloss over the
flanks and a progression from
the rear of the body towards the front of the body. I don't think
that there is a good test for this
condition. It is necessary to supplement hormones and see if
there is a beneficial effect to rule in or
rule out sex hormone responsive dermatosis. For males, methyltestosterone
is usually used at a
dosage of 1 mg/kg (up to 30mg maximum) every 48 hours until these is
a response to treatment or
three months have passed with no response. If there is a response to
treatment the length of time
between methyltestoterone dosages is increased to the longest interval
that will control the problem,
usually at least once weekly.
Growth hormone response dematosis is hard to diagnose because the growth
hormone levels in
serum in affected dogs can be in the normal ranges. A stimulation test
is usually necessary to rule this
condition in or out. This can be done by measuring baseline values
and then using xylazine (Rompun
Rx) or clonidine to stimulate production of growth hormone and then
drawing follow-up blood
samples at regular intervals for a couple of hours. If growth hormone
levels do not rise in these tests,
a growth hormone responsive dermatosis is likely, if clinical signs
are present.
I am assuming that both testicles were located and removed at the time
of neutering. If there is any
question about this, it may be worth making sure. There are dogs that
have skin disease similar to
what you are seeing due to Sertoli cell tumors of the testicle, which
is more common in retained
testicles. Virtually all veterinarians do remove the retained testicle,
but I have treated a patient who
was supposedly neutered at a young age but had one retained testicle
that was not removed.
It is difficult and time consuming to work through all the possibilities
when hormonal skin disease
signs are present but it is usually possible to identify the problem
and to help with it. If your
veterinarian is uncomfortable pursuing a diagnosis due to unfamiliarity
with these conditions, a
veterinary endocrinologist or dermatologist may be able to help and
it is possible to ask your vet for
referral to a specialist in most areas.
Mike Richards, DVM
10/1/2000
Last edited 04/27/04
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