Clinical, immunological and histopathological findings in a subpopulation of dogs with pododermatitis

Abstract

Clinical, immunological and histopathological findings in 20 adult dogs of varying breeds with chronic (>or=6 months) inflammation confined to the pedal skin were compared over a 2-year period with those of a group of age-matched controls (n=20). All affected dogs were pruritic but systemically well. Lesions were present on all four feet in 18/20 cases. Affected feet were characteristically erythematous, swollen, painful and alopecic. Sinus tracts were evident in 4/20 dogs. Despite a methodical series of diagnostic tests, no underlying cause was identified. None of the dogs responded to antimicrobial therapy administered for 8 weeks, none had evidence of ectoparasitism and none satisfied the criteria for atopic dermatitis. There was no response to a dietary trial using a novel protein source. The condition was characterized histopathologically by epidermal hyperplasia, hyperkeratosis, spongiosis, dermal oedema and perivascular aggregates of lymphocytes and plasma cells. Clinical signs did not correlate with histopathological findings. Affected dogs had significantly elevated serum IgG and IgM concentrations. The results of lymphocyte proliferation assays and phenotypic studies to determine the relative percentage of CD3+, CD4+, CD8+ and CD21+ lymphocyte subsets, and the ratio of CD4+/CD8+ cells were not significantly different between groups. No age, sex or seasonal predilections were noted. All dogs subsequently responded to immunosuppressive doses of prednisolone or cyclosporin. The term immunomodulatory-responsive lymphocytic-plasmacytic pododermatitis is proposed to denote what may be a previously unrecognized condition in some dogs with pododermatitis of undetermined aetiology.

Evaluation of Th1‐like, Th2‐like and immunomodulatory cytokine mRNA expression in the skin of dogs with immunomodulatory‐responsive lymphocytic–plasmacytic pododermatitis

“…suggested that the severity of the inflammatory response could explain the enhanced expression of IL‐6 mRNA in dogs with anal furunculosis, a theory that is also potentially applicable to dogs with ImR‐LPP. In addition, based on the clinical signs previously reported for this condition, 5 the role of IL‐6 in skin repair 46 may have been a factor underpinning the increased transcript levels recorded in this study.…”

“…The authors previously proposed the term immunomodulatory‐responsive lymphocytic–plasmacytic pododermatitis (ImR‐LPP) to denote a subpopulation of dogs with idiopathic disease 5 . Affected individuals were systemically healthy but had persistent (≥ 4 months) inflammation and pruritus confined to the pedal skin.…”

Staphylococcus pseudintermedius in the dog: taxonomy, diagnostics, ecology, epidemiology and pathogenicity

“…Staphylococcus pseudintermedius is the major cause of canine pyoderma. Furthermore, S. pseudintermedius is also frequently isolated from canine ear and wound infections, and can be a complicating factor in immunomodulatory‐responsive lymphocytic–plasmacytic pododermatitis 71,113,114 . Additionally, it is the staphylococcal species most commonly isolated from canine urinary tract infection 115–117 .…”

Ciclosporin 10 years on: indications and efficacy

“…However, in some cases, despite a thorough work up, a specific cause remains elusive. One study reported success in using ciclosporin to treat idiopathic pododermatitis in seven dogs (Breathnach and others 2005). …”