CHAPTER 7 ANTIBIOTIC STEWARDSHIP AND EMERGING RESISTANT BACTERIAL INFECTIONS 151
TOPICAL THERAPEUTICS FOR THE PYODERMA PATIENT
Chlorhexidine gluconate: less irritating than benzoyl peroxide, good residual effect,
good for gram-positive, poor against pseudomonads, percent concentration may be
important.Benzoyl peroxide: oxidizing agent, lowers skin pH, can be drying and irritating, dis-
rupts bacterial cell membranes; caution – may bleach fabrics.
Ethyl lactate 10%: lowers skin pH, variable clinical response.
Retapamulin (Altabax): excellent penetration, gram-positive bacteria, expensive.
Dilute bleach formulations (shampoos, rinses, sprays, soaks): 0.00156% kills 100% of
staphylococci, yeast and pseudomonads; bleach bath concentrations recommended at
0.003–0.007%.Accelerated hydrogen peroxide: stabilized solutions of hydrogen peroxide for
extended bactericidal activity.
N-acetyl-L-cysteine for disruption of biofilm production; used as a topical (2%) in
otic preparations for infections and persistent secretory otitis media (PSOM); oral
administration (600 mg/day as a mucolytic agent) may help prevent ototoxicity from
medications (i.e., gentamycin, amikacin) and may help decrease mucoid accumula-
tion in the middle ear in cases of PSOM.TrizEDTA and N-acetyl-L-cysteine can disrupt biofilms, facilitating their removal and
enhancing penetration of antimicrobials (otitis).
Amikacin topical 1%.
Fusidic acid 2% cream: not available in all countries.
Mupirocin 2% ointment: excellent penetration, mostly gram-positive sensitivity, bac-
teriostatic; good residual effect in reservoir locations; should be reserved for more
resistant infections.Sucralfate (1 g/2 mL saline) and cicalfate (10% in DMSO) containing skin creams may
inhibit bacterial growth; further investigation needed.
IIS-PAA (incomplete iron salt of polyacrylic acid); ingredient may prove to be bene-
ficial in treating resistant strains ofStaphylococcusandPseudomonasspp.
Lactoferricin (LFcin) is a peptide under investigation for antimicrobial activity.
Silver salts, silver nanoparticles, and micronized silver; potential antibacterial proper-
ties/lysis of the bacterial cell wall, may inhibit biofilm production/no data to support
biofilm degradation.Systemic Treatment Options for Methicillin-ResistantStaphylococcusBased
on Culture and Sensitivity Testing
Chloramphenicol: 25–40 mg/kg BID to TID; GI upset, bone marrow suppression and
peripheral neuropathy in large breed dogs; aplastic anemia in humans.
Potentiated sulfonamides: 10–15 mg/kg BID; keratoconjunctivitis sicca, hypersensi-
tivity reactions, lowered serum thyroid measurement; doberman pinschers and rot-
tweilers reported to be more sensitive.Amikacin injectable: 20 mg/kg q24h; painful, potential for nephrotoxicity – renal
monitoring required.