DERMATOLOGY
shampoos is in the dog suffering from recurrent
folliculitis (idiopathic of secondary to endocrine
or allergic skin disease). Here antibacterial shampoos may have a prophylactic effect if used regularly e.g. weekly or every two weeks.
3. Fungal skin infections
Malassezia dermatitis is a fungal skin infection. The
pathogenic agent, Malassezia pachydermatis, is a lipophilic yeast belonging to the cutaneous microflora
of the normal dog, along with Staphylococcus pseudintermedius. In certain conditions, related to cutaneous and/or immune-mediated factors, Malassezia
may proliferate within the stratum corneum. The
subsequent yeast overgrowth may then acquire a real
pathogenic capacity and initiate a true dermatitis. It is
recognised as a secondary pathogen in a large number of skin conditions, e.g. in dermatoses associated
with dry or greasy scales, inflammatory and pruritic
skin conditions and in various pyodermas. It may also
be a primary pathogen.
Topical therapy is often used for the treatment of
Malassezia infections and may also be beneficial when
used routinely to help prevent recurrence of infection.
Shampoo therapy is most useful for generalised infections, while localised infections may benefit from
creams, lotions and sprays. Dogs with severe generalised Malassezia infections show the most rapid response where shampoo therapy is used in conjunction with systemic therapy (as compared to topical
therapy or systemic therapy alone). Active ingredients
in topical preparations that may be useful in managing
Malassezia infections include: imidazoles (miconazole, ketoconazole, enilconazole), chlorhexidine, and
piroctone olamine.
Imidazoles act by interfering with cell wall formation
in fungal and yeast organisms, which increases cellular permeability, thus suppressing metabolic function
and inhibiting growth. There has also been evidence
that ketoconazole exerts an inhibitory effect on keratinocy \