The use of Antiseptics in Veterinary Dermatology

Scientific Investigation and Veterinary information
N.14
The use of Antiseptics in Veterinary Dermatology
Luca Guardabassi
Assistant Professor of Clinical Microbiology, University of Copenhagen (Denmark)
Giovanni Ghibaudo
DVM, Clinica Veterinaria Malpensa di Samarate, Varese (Italy)
www.icfpet.com
List of publications
icf informa n°1
Malassezia
Dr.ssa Fabia Scarampella - Dr.ssa Chiara Noli
icf informa n°2
Otocariasi
Dr. Fabrizio Fabbrini
icf informa n°3
Piodermiti
Dr.ssa Silvia Schiavi - Dr.ssa Antonella Vercelli
icf informa n°4
Malattia paradontale
Dr.ssa Dea Bonello
icf informa n°5
Malattie del canale auricolare esterno
Dr.ssa Luisa Cornegliani - Dr Giovanni Ghibaudo
icf informa n°6
La pulizia dell’orecchio
Dr.ssa Chiara Tiegh
icf informa n°7
Seborrea
Dr Francesco Albanese
icf informa n°8
Dermatite atopica
Dr.ssa Franca Galeotti
icf informa n°9
Otiti
Dr Massimo Beccati
icf informa n°10
Tris-EDTA
Dr Giovanni Ghibaudo
icf informa n°11
Piodermiti e Piodermiti ricorrenti
Dr. Fabrizio Fabbrini
icf informa n°12
Utilizzo prodotti icf in corso di Piodermite e Dermatite
da Malassezia nel cane
Laboratorio icf
icf bulletin n°14
Utilizzo dei prodotti antisettici in dermatologia veterinaria
Dr L. Guardabassi - Dr G. Ghibaudo
www.icfpet.com
Scientific Investigation and Veterinary information
The use of Antiseptics in Veterinary Dermatology
Luca Guardabassi
Assistant Professor of Clinical Microbiology, University of Copenhagen (Denmark)
Giovanni Ghibaudo
DVM, Clinica Veterinaria Malpensa di Samarate, Varese (Italy)
The recent development of multi-resistant bacteria in veterinary medicine, especially methicillinresistant staphylococci, highlights a need for alternative therapeutic approaches able to eliminate bacterial strains that are virtually resistant to all oral antibiotics, while minimising further selection of
antibiotic-resistant strains. Among the various recommendations made by experts in the veterinary field
(1), topical use of antimicrobial products, including antiseptics, seems the simple and effective treatment
for surface skin multi-resistant bacterial infections. Besides clinical efficacy, local antimicrobial treatment limits the spread of these bacteria, thus reducing the need for last-resort broad-spectrum systemic
antibiotics, which are the main cause behind the spread of antibiotic-resistant bacteria. In veterinary
dermatology, situations in which topical antiseptic treatment is a valid alternative to systemic antibiotic
therapy are frequent (2, 3). These situations include otitis externa and some forms of surface pyoderma
(which only present bacterial overgrowth) such as intertrigo or pyotraumatic dermatitis, and localised
surface pyoderma such as mucocutaneous pyoderma
The use of antiseptics that possess antibacterial properties presents many advantages compared to systemic
antibiotic therapy.
These advantages can be summarised in the five points
listed below.
1) Clinical efficacy towards multi-resistant bacterial
strains.
Antiseptics target microorganisms by mechanisms of
action that differ from those of antibiotics. Studies in
human medicine have found that antiseptic products
have the same efficacy against bacteria that are resistant
and sensitive to antibiotics. For instance, various
studies on methicillin-resistant Staphylococcus aureus
(MRSA) have proved that methicillin-resistance does
not influence susceptibility to chlorhexidine (4), which
is currently used successfully to decolonise MRSA in
humans (5).
Foto G.Ghibaudo
Bulldog male 2 y.o. Skin fold intetrigo
Local antimicrobial treatment is an alternative or
complimentary approach to antibiotic treatment of
methicillin-resistant S. intermedius infections that
have recently emerged in small animals. (6)
2) Broad spectrum antimicrobial action.
While antibiotics, even the broad-spectrum ones,
possess a limited spectrum of activity (i.e. cephalosporins are not active against Pseudomonas aeruginosa
and Malassezia), some antiseptics such as chlorhexedine and phytosphyngosine are microbicidal against
almost all the main pathogens in veterinary dermatology, including staphylococci, streptococci, gramnegative rods (with the sole exception of certain P.
aeruginosa strains) and yeasts. The choice of antiseptics is therefore particularly advantageous in the treatment of mixed infections that involve various bacterial
species and microorganisms. This phenomenon is
rather common in otitis externa in dogs and infected
wounds.
3) Complimentary non-antimicrobial properties.
Most antiseptics possess secondary beneficial properties in addition to their antimicrobial action.
Chlorhexidine’s emollient property is useful for dry and
dehydrated skin. Benzoyl peroxide is a keratolytic,
antipruritic and degreasing agent.
Phytosphyngosine is a natural component of the corneal layer; it guarantees epidermal barrier function with
keratomodulating effects and by controlling sebum
production, besides performing a local antiinflammatory action. Tris-EDTA has a synergic action with various
antibiotics, and it is highly recommended for infections
caused by gram-negative rods. The synergic effect
seems to issue from a series of mechanisms related to
the increase in pH and kelation of divalent cations.
Foto G.Ghibaudo
Pyoderma in a cat 7 y.o. male with atopic dermatitis
Foto G.Ghibaudo
Moreover, Tris-EDTA increases sensitivity in
P. aeruginosaI strains resistant to fluoroquinolones,
most likely by inhibiting their resistance mechanism.
Hence, cases of otitis externa associated with
resistant strains can be successfully treated by combining Tris-EDTA and chlorhexidine for topical
administration. This combination is synergic and,
therefore, allows the use of low doses of chlorhexidine (0.15%) that are not ototoxic. (7, 8, 9)
4) Low impact on the spreading of resistance.
According to the current scientific knowledge,
antiseptics do not seem to directly enhance selection
of antibiotic resistance and, above all, bacteria do not
seem to acquire resistance to the antiseptic concentrations used for topical treatment. Though bacterial
strains that have acquired resistance to antiseptics
and disinfectants have been detected, this phenomenon does not seem to be of clinical importance since
the antiseptic concentrations used in clinical practice
are notably higher than those required to eliminate
“resistant” strains. (4, 10, 11)
Using Antiseptics in Veterinary Dermatology
5) Action circumscribed to the site of the infection.
Antiseptics are not absorbed in the blood stream and
solely act on the site of infection. Hence, most antiseptics have no secondary effects on animal health. Instead, antibiotics are a frequent cause of side-effects such
as vomiting, diarrhoea, allergies, etc. Moreover, unlike
oral antibiotics, antiseptics do not influence the composition of intestinal microflora, for instance by selecting pathogenic bacteria such as Clostridium difficile or
by encouraging the development of antibioticresistance in opportunist pathogens like Escherichia
coli and Enterococcus faecium.
All antiseptic products must be used following the
indications and the concentrations indicated in the
product leaflet.
Foto G.Ghibaudo
Coltura batterica su Agar-sangue
The product’s clinical efficacy is ensured by close
compliance with exposure times and by educating
owners to strictly follow the application times and
frequency recommended in the veterinary prescription. To avoid product contamination, all dilutions
must be prepared with sterile water, and solutions
must be stored as specified according to the
manufacturer’s instructions. Although Tris-EDTA
has a synergic effect when combined with certain
antibiotics, it would be wrong to stretch this property to all antiseptic products.
Foto G.Ghibaudo
Coltura AS Staphylococcus pseudoitermedius
This article highlights the advantages of using
antiseptics in veterinary dermatology but it also
aims at promoting their rational and appropriate use.
References
1) Guardabassi L., Houser G. A., Frank L. A. and
Papich M. G. et al. 2008. Guidelines for antimicrobial use in small animals. In “Guide to antimicrobial use in animals”. Eds. Guardabassi L.,
Jensen L. B. and Hilde K. pp. 183-206. Blackwell
Publishing.
2) Guaguere E. 1996. Topical treatment of canine
and feline pyoderma. Veterinary Dermatology 7:
145-151.
3) Lloyd D. H. 2006. Update on Therapy of
Canine Pyoderma. World Small Animal Veterinary
Association World Congress Proceedings.
(http://www.vin.com/proceedings/Proceedings.plx
?CID=WSAVA2006&PID=15762&O=Generic)
4) Weber D. J. And Rutala W. A. Use of germicides in the home and the healthcare setting: is there
a relationship between germicide use and antibiotic resistance? Infection Control and Hospital
Epidemiology 10: 1107-1119.
5) Simor A. E., Phillips E., McGeer A., Konvalinka A., Loeb M., Devlin R. H. and Kiss A. 2006.
Randomized controlled trial of chlorhexidine
gluconate for washing, intranasal mupirocin, and
rifampin and doxycycline versus no treatment for
the eradication of methicillin-resistant Staphylococcus aureus colonization. Clinical Infectious
Diseases 44:178–185.
6) Loeffler A., Linek M., Moodley
A., Guardabassi L., Sung J. M. L., Winkler M.,
Weiss R. And Lloyd D. H. 2007.
First report of multiresistant, mecA-positive
Staphylococcus intermedius in Europe: 12 cases
from a veterinary dermatology referral clinic in
Germany.Veterinary Dermatology 18: 412-421.
7) Ghibaudo G., Cornegliani L., Martino P. Efficacia e tolleranza di una soluzione con tris-EDTA e
clorexidina digluconato 0,15% (Otodine®) nella
terapia dell’otite cronica batterica esterna canina.
2007 Summa n.4, pp.23-30.
8) Merchant SR, Neer TM, Tedford BL, et al.
Ototoxicity assessment of a chlorhexidine otic
preparation in dogs. Prog Vet Neurol 1993;
9) Mills P.C. et coll.: Ototoxicity and tolerance
assessment of a TrisEDTA and
polyhexamethylene biguanide ear flush formulation
in dogs, J. vet. Pharmacol. Therap. 28, 391–397,
2005.
10) Russell A. 2003. Biocide use and antibiotic
resistance: the relevance of laboratory findings to
clinical and environmental situations. The Lancet
Infectious Diseases 3: 794 – 803.
11) Vali L., Davies S. E., Lai L. L. G., Dave J. and
Amyes S. G. B.. 2008. Frequency of biocide
resistance genes, antibiotic resistance and the effect
of chlorhexidine exposure on clinical methicillinresistant Staphylococcus aureus isolates. Journal of
Antimicrobial Chemotherapy 61: 524-532.
Luca Guardabassi
Assistant Professor of Clinical Microbiology, University of Copenhagen (Denmark)
Giovanni Ghibaudo
DVM, Clinica Veterinaria Malpensa di Samarate, Varese (Italy)
www.icfpet.com
www.icfpet.com