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a r e g ula r c l i n i c a l u p da t e b ro u gh t t o you b y Eukanub a Ve te r inar y Die ts
issue 5, march 2009
Dietary management
of canine atopic dermatitis
By Professor Dr. Ralf S. Mueller,
DipACVD, FACVSc, DipECVD
Welcome to theVeterinarian from Eukanuba Veterinary Diets.
Introduction
The aim of theVeterinarian is to give the busy clinician quick and
Canine atopic dermatitis (fig 1) is a
easy to read practical information, and top-tips, on common
clinical problems.
common skin disease in small animal
practice.1 It is defined as a genetically
predisposed inflammatory and pruritic
allergic skin disease with characteristic
clinical features and is most commonly
Figure 1.
A young English
(but not necessarily) associated with IgE
antibodies to environmental allergens.2
Bull Terrier with
atopic dermatitis
Clinical Presentation and
Medical Management
Clinically, pedal (fig 2), ventral (fig 3) and
facial pruritus as well as otitis externa
are hallmarks of the disease. Secondary
infections are frequently seen and with
the associated self-trauma and chronic
inflammation also contribute to the clinical
About the author
signs. Atopic dermatitis can be treated
symptomatically with anti-inflammatory
Prof. Dr. Ralf S. Mueller graduated in Munich, Germany, in 1985 and worked in
drugs or with allergen-specific immuno-
several large and small animal practices before completing a residency in veterinary
therapy (ASIT). ASIT is to date the only
dermatology at the University of California, Davis. Later, he was director of the
specific treatment for canine atopic der-
Animal Skin & Allergy Clinic, a dermatology referral practice in Melbourne,
Australia, together with his partner and wife Dr. Sonya Bettenay. He joined
matitis.3 Symptomatic treatment of atopic
the faculty at Colorado State University, USA in 1999. Since 2004 he is
dermatitis comprises oral and topical
Chief of Dermatology & Allergy at the veterinary faculty, Ludwig
glucocorticoids,4 cyclosporin A,4,5 antihis-
Maximilian University in Munich, Germany.
tamines,2,6 fatty acid supplementation2,7 as
well as topical treatment with antipruritic
Dietary management of canine atopic dermatitis
results of this study, in addition to the
Figure 2. Alopecia and swelling of a distal
Figure 3. Hyperpigmentation, erythema
extremity due to atopic dermatitis and
and alopecia of the ventrum due to chronic
conventional therapies, changing the diet
secondary infection in an 8 year old
pruritus in an atopic 8 year old female
of dogs with atopic dermatitis may be a
female Golden Retriever.
Golden Retriever.
useful adjunctive measure to therapy.
Discussion
shampoos. The frequently observed secon-
patient-pruritus levels using a visual ana-
Diets manufactured for dogs with atopic
dary infections must also be addressed.
logue scale.
dermatitis typically have a higher content
More recently, diets recommended to help
of essential fatty acids (EFA) which may
with the management of canine atopic
Results
explain their influence on allergic skin
dermatitis have been introduced to the
After eight weeks on the new foods, dogs
disease.10 Proposed mechanisms of action
market.
assigned to diet A (n=14) showed signifi-
of essential fatty acids include modulation
cantly less pruritus (p = 0.019), diet B
of eicosanoid production, inhibition of
Dietary Management:
new study
(Eukanuba Veterinary Diets® Dermatosis FP;
cellular activation and an increase in
n=12) fed dogs had a significant decrease
epidermal barrier function. EFA’s can
In one multi-centered, double-blinded,
in both the CADESI and pruritus scores
influence the immune system by acting as
randomised study, fifty dogs with atopic
(p = 0.043 and p = 0.012 respectively).
second messengers, regulators of signal
dermatitis were fed either one of three
Diet D (n=12) significantly reduced the
transducing molecules or transcription
commercial veterinary diets marketed for
CADESI score and diet C (n=12) had no
factors.11 In a recent study, it was shown
dogs with atopic dermatitis (diets A-C) or
significant effect on the pruritus or
that EFA’s inhibit T-cell proliferation in
a widely distributed supermarket food
CADESI scores (figs 4, 5). Based on the
dogs.12 Thus, it is possible that the improve-
(diet D) for eight consecutive weeks.8
Atopic dermatitis was diagnosed in these
dogs using Willemse’s criteria and
through the exclusion of differential
diagnoses. Flea and tick control using a
monthly fipronil spot-on was administered
to all dogs prior to and during the study
period. Monthly evaluations included
veterinary graded lesional scores, using an
established scoring system (CADESI =
Canine Atopic Dermatitis Extent and
Severity Index)9 and owner evaluated
Top Tips
• Any atopic dog may develop secondary infections at any time. Thus, with increased pruritus,
cytology is essential to diagnose these secondary infections.
• Dietary management is particularly important in dogs allergic to both environmental and
dietary antigens. In these dogs, the smallest amounts of antigens can lead to an allergic
flare and thus great care has to be taken in selecting medications, supplements and treats
without flavours.
• The dose of a medication that is costly or has a high rate of adverse effects may be reduced
if concurrent antihistamines, essential fatty acids, topical therapy and/or dietary management
are used.
Dietary management of canine atopic dermatitis
ment of the dogs in this study was due to
Conclusion
the feeding of a good quality essential
Feeding a special formulated canine skin
fatty acid source. Calculation of n-6:n-3
diet may be helpful alongside medical
13
ratios have been reported to be of value.
therapies in decreasing pruritus and skin
In this study, the amount and type of fatty
lesions in individual dogs with atopic
acids in the diets varied. Eukanuba FP
dermatitis.
contained a relatively low n-6:n-3 ratio of
Did you
know ?
• That just one flavoured heart worm
prevention or antibiotic tablet
may cause increased pruritus and
allergen-specific IgE in sensitive dogs?
2.7:1. The other two test diets A and C
• That an increased intake of essential
fatty acids in atopic dogs may reduce
the need of glucocorticoids to control
clinical signs?
had a ratio of 4.7:1 and 5.4:1 respectively.
The improvement seen with Eukanuba FP
may support lower ratios than 5:1.
Calculation of n-6:n-3 ratios may not be
the only story, as the long chain fatty acids
are more potent substrates for eicosanoid
production than their shorter counterparts.14 Diet A and Dermatosis FP contained
the highest percentage of the omega-3
References
eicosapentaenoic acid, docosahexaenoic
acid and other long chain fatty acids. It is
possible that this contributed to the
clinical effects seen while using these two
diets.
Figure 4.
Diet A
40
Dermatosis FP
Diet D
Diet C
CADESI scores at
35
week 0 and week 8
CADESI score
30
of the study for
25
each diet group.
20
*P <0.05
15
10
*
*
5
0
0
Pruritus score
9
8
Diet A
0
8
Dermatosis FP
0
8
Diet C
0
8
Week
Figure 5.
Diet D
8
Pruritus scores at
7
week 0 and week 8
6
of the study for
5
each diet group.
*
4
*P <0.05
3
*
2
1
0
0
8
0
8
0
8
0
8
Week
1. Health status and population characteristics
of dogs and cats examined at private
veterinary practices in the United States.
Lund EM, Armstrong PJ, Kirk CA, et al
JAVMA 1999; 214: 1336-41.
2. The ACVD task force on canine atopic
dermatitis: forewords and lexicon. Olivry T,
DeBoer DJ, Griffin CE, et al. Vet Imm and
Immunopath 2001; 81: 143-6.
3. Effect of hyposensitisation on atopic
dermatitis in dogs. Willemse A, Van den
Brom WE, Rijnberk A. JAVMA 1984; 184:
1277-80.
4. Evidence-based veterinary dermatology: a
systematic review of the pharmacotherapy
of canine atopic dermatitis. Olivry T,
Mueller RS. Vet Derm 2003; 14: 121-46.
5. A systematic review and meta-analysis
of the efficacy of cyclosporine for the
treatment of canine atopic dermatitis.
Steffan J, Favrot C, Mueller RS. Vet
Derm 2006; 17: 3-16.
6. Use of antihistamines to control pruritus
in atopic dogs. Paterson S. JSAP 1994;
35: 415-9.
7. Effect of omega-3 fatty acids on canine
atopic dermatitis. Mueller RS, Fieseler KV,
Fettman MJ, et al. JSAP 2004; 45: 293-7.
8. The evaluation of commercially available
veterinary diets recommended for dogs
with atopic dermatitis. Glos K, Linek M,
Loewenstein C, Mayer U, Mueller RS.
Vet Derm 2008; 19: 280-7.
9. Validation of CADESI-03, a Severity Scale
for Clinical Trials Enrolling Dogs with
Atopic Dermatitis. Olivry T, Marsella R,
Iwasaki T, Mueller RS. Vet Derm 2007;
18: 78-86.
10.Nutritional Management of Canine Atopy
in 47 Dogs: A Retrospective Study.
Rosychuk RAW. Recent Advances in
Canine and Feline Nutrition, Iams
Nutrition Symposium 2000; III: 287-91.
11.Fatty acids and immune responses a new perspective in searching for clues
to mechanism. Hwang D. Annual Reviews
of Nutrition 2000; 20: 431-56.
12.The influence of polyunsaturated fatty
acids on the T-cell response in dogs with
atopic dermatitis. Stehle ME, Goebel T,
Hancaruk M, Mueller RS.
Vet Derm 2007; 18: 194.
13.Evaluation of effects of dietary n-6 to
n-3 fatty acid ratios on leukotriene B
synthesis in dog skin and neutrophils.
Vaughn DM, Reinhart GA, Swaim SF,
et al Vet Derm 1994; 5: 163-73.
14.Fat and fatty acids. Bauer JE. Nutrient
requirements of dogs and cats.
Washington: The National Academies
Press, 2006: 81-109.
ResearchNews
from P&G Pet Care
manufacturers of Eukanuba, Iams and Eukanuba Veterinary Diets
Surgical and dietary management of canine perianal fistula disease
Canine perianal fistula disease (PAF) is a chronic, debilitating, painful and progressive disease of
the anus, perianal skin, anal sacs and adjacent tissues (fig 1). It is characterised by inflammation,
ulceration and draining tracts. In one study 84% of cases were German Shepherd Dogs.1 Irish
Setters, retrievers and spaniels are also affected.2
A recent independent study reported the
of clinical signs while only 21% continued
results of feeding Eukanuba Veterinary
to have intermittent licking, diarrhoea,
Diets Dermatosis FP Fish & Potato (fig 2)
constipation, tenesmus or decreased
in conjunction with en bloc surgical excision
anal tone on digital examination.
®
of all visibly diseased tissue and bilateral
anal saculectomy in a series of PAF dogs.3
The authors concluded that dogs with
Antibiotics were prescribed prior to the
PAF can be successfully treated with en
study. Dermatosis FP was fed exclusively
bloc surgical excision of diseased tissue
to all but one dog before the study and
and bilateral anal saculectomy; and
feeding continued post-operatively for 1
long-term perioperative feeding of a novel
year.
fish and potato diet (Dermatosis FP),
enriched with omega-3 fatty acids,
Thirty-three dogs completed the study of
supports the management of the disease.
which 97% had concurrent anal sac disease
Figure 1. Perianal fistula disease.
at the start. At the 3-month post-operative
Image courtesy of Professor Dick White,
evaluation 70% had no clinical signs or
Dick White Referrals, Newmarket, UK
evidence of fistulas. At the 1-year evaluation
88% had complete resolution of visible
fistula disease, 79% were completely free
PAF is a well-documented disease but
its cause is still poorly understood and
includes, (1) an anatomic predisposition
of a broad-based tail, low tail carriage and
increased density of apocrine sweat glands
in the zona cutanea, (2) an immunemediated basis is suggested due to a
positive response to prednisolone, azothioprine, cyclosporine and tacrolimus.2,3
Treatment options include medical and
surgical but both have potential complications making alternative treatment
strategies desirable.
Figure 2. Eukanuba Veterinary Diets®
Dermatosis FP Fish & Potato
References
1. Pathology of surgically resected tissue from
305 cases of anal furunculosis in the dog. Day
MJ & Weaver BMQ. JSAP 1992; 33: 583-589
2. Rectoanal disease. Zoran DL. Textbook of
Veterinary Internal Medicine, 6 th Ed, 2005; Eds
Ettinger SJ & Feldman EC: 1408-1420
3. Long-term evaluation of canine perianal fistula
disease treated with exclusive fish and potato
diet and surgical excision. Lombardi RL &
Marino DJ. JAAHA 2008; 44: 302-307