Small Animal Dermatology, 3rd edition

chapter 13 Bacterial Pyoderma....................................

DEFINITION/OVERVIEW

 Bacterial infections of the skin and adnexal structures.

 Microbiome: mixed population of microorganisms that colonize the skin, gut, oral

cavity, and other sites: up to 90% of total cells in an individual may be microbial.

 Pyoderma is a term used to describe any skin disease that is pyogenic (has pus);

commonly used in veterinary medicine to describe superficial and deep bacterial

infections.

ETIOLOGY/PATHOPHYSIOLOGY

Skin infections occur when the surface integrity of the skin has been broken, the skin

has become macerated (e.g., by chronic exposure to moisture), normal bacterial flora

have been altered, circulation has been impaired, and/or immunocompetency has been

compromised.

 Primary types of cutaneous bacterial colonies: resident and transient.

 Resident:
“Normal” bacteria found on “normal” skin that can multiply to establish and

maintain colonies

Normal skin flora (microbiome) vary with body site (greater diversity on haired

skin versus mucosal or mucocutaneous surfaces)

Serve as a component of the immune defense system (carry important func-

tional genes responsible for synthezing numerous metabolites that influence

host health)

Bacterial dysbiosis: alterations in the resident microbiome may influence disease

(cause or effect), i.e., atopic skin has a significantly less diverse bacterial and

fungal microbiome than does healthy skin

Alteration of the microbiome may allow for greater management of the specific

disease

Bacteria are located in the superficial epidermis and infundibulum of the hair

follicle and receive nutrients via sebum and sweat; these organisms live in sym-

biosis and help inhibit colonization by invading bacteria via bacteriocins

Blackwell’s Five-Minute Veterinary Consult Clinical Companion: Small Animal Dermatology, Third Edition.
Karen Helton Rhodes and Alexander H. Werner.
©2018 John Wiley & Sons, Inc. Published 2018 by John Wiley & Sons, Inc.

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