Candidiasis
Contact dermatitis
Contact dermatitis is an inflammatory reaction to direct contact with an irritant (contact irritant dermatitis) or allergen (contact allergic dermatitis)
Ho KK, Campbell KL, Lavergne SN. Allergic Contact dermatitis: a comparative and translational review of the literature. Vet Dermatol 2015; 26: 367
Superficial pustular drug reactions
Superficial pustular dermatophytosis
Superficial spreading pyoderma/exfoliative superficial pyoderma
None had Ab to desmocolin
Background – The microscopic and microbial features of the spreading epidermal collarettes of canine exfoliative superficial pyodermas are poorly characterized.
Objectives – To characterize the clinical, cytological, microbial and histopathological features of epidermal collarettes in five dogs.
Results – Cytology from the margins of collarettes identified neutrophils, extracellular and intracellular cocci within neutrophils but no acantholytic keratinocytes. Phenotypic and genotypic analyses identified all bacterial isolates from the centre and margin of five epidermal collarettes as Staphylococcus pseudintermedius. PCRs of collarette-associated Staphylococcus strains did not amplify genes encoding for the known exfoliative toxins expA and expB, whereas the predicted siet and speta amplification products were detected in all isolates. Microscopically, epidermal collarettes consisted of interfollicular, epidermal spongiotic pustules. Advancing edges of lesions consisted of peripheral intracorneal clefts in the deep stratum disjunctum above an intact stra- tum compactum; they contained lytic neutrophil debris, bacterial cocci and fluid, but no acantholytic keratinocytes. This intracorneal location of bacteria was confirmed using Gram stains and fluorescent in situ hybridization with eubacterial- and Staphylococcus-specific probes. The indirect immunofluorescence staining patterns of desmoglein-1, desmocollin-1, claudin-1, E-cadherin and corneodesmosin were discontinuous and patchy in areas of spongiotic pustules, whereas only that of corneodesmosin was weaker and patchy in advancing collarette edges.
Conclusion – Epidermal collarettes represent unique clinical and histological lesions of exfoliative superficial pyodermas that are distinct from those of impetigo and superficial bacterial folliculitis. The characterization of possible causative staphylococcal exfoliatin proteases and the role of corneodesmosin in collarette pathogenesis deserve further investigation.Impetigo (can have a generalised form)
Bacterial - Staphlococcal
Lichenoid psoriaform dermatitis of Springer Spaniels
The lichenoid pattern of skin inflammation is when there is a band of cells, usually lymphocytes and plasma cells, beneath the epidermis. It is a pattern of immune response to local antigens and is a component of cytotoxic interface dermatitis and other diseases such as this. It is a common pattern of mucous membranes, and the pad.
Psoriasiform lichenoid dermatitis secondary to Atopica.
Just like springer spaniel disease associated with atopica
Werner AH1. Psoriasiform-lichenoid-like dermatosis in three dogs treated with microemulsified cyclosporine A. J Am Vet Med Assoc. 2003; 223(7): 1013-1016, 986.
Biopsy specimens from 2 dogs described in the present report had similar lesions with parakeratosis, band-like lymphocytic infiltrates, and clusters of coccoid bacteria that were often in intraepidermal microabscesses. These histologic findings (epidermal hyperplasia, lichenoid dermatitis, and intraepidermal microabscesses) are identical to those found in psoriasiform-lichenoid dermatitis.
Mycosis fungoides – Epitheliotropic lymphoma
CD3+, D45RA+
Vasculitis
Drug reaction
Sterile Pustular Erythroderma of Miniature Schnauzers/ Superficial suppurative necrolytic dermatitis of Miniature Schnauzers aka sterile pustular dermatitis
Murayama et al 2008 Vet Derm 19: 395-399
Contact hypersensitivity to shampoos
Neutrophilic VP and superficial and deep PVDCanine sterile eosinophilic pustulosis
Scott DW. Sterile eosinophilic pustulosis in the dog. J Am Anim Hosp Assoc 1984; 20: 585-589.
Scott DW. Sterile eosinophilic pustulosis in dog and man: Comparative aspects. J Amer Acad Dermatol 1984; 16: 1022-1026.
Eosinophilic epidermal pustulesIdiopathic Linear Pustular Acantholytic Dermatitis
Clinically linear
Can be anywhere
Inguinal or facial in 2 reports
Looks like PfA linear, well-circumscribed, raised lesion, about 2.5 cm in width by 16.5 cm in length, extended caudally and continuously from a point cranial and dorsal to the right lip commissure across the masseter region (Fig. 1). The lesion consisted of coalescent annular papules, pustules and crusts. Mild erythema and scaling were also present. The differential diagnoses included ILPAD, a nevoid malformation, or linear trauma with secondary infection.
Beningo KE, Scott DW. Idiopathic linear pustular acantholytic dermatosis in a young Brittany Spaniel dog. Vet Dermatol. 2001 12: 209-213.
Scott DW. Canine idiopathic linear pustular acantholytic dermatosis: a second case. Vet Dermatol 2003; 14: 275.
Pemphigus foliaceus (Dsg 1 - Desmosome)
Classical Pf has nasal planum, bridge of nose, +- ears and extending to surround the eyes.
Acantholytic disease that histologically looks the same but clinically have coalescing pustules –
No collarettes but can mimic. Differentiation is on the normal skin internally in Pf but not in mucocutaneous pyoderma.
Pinpoint crusts and erosions
Foot pad lesions are on the pads
Generalised in 60%
Atypical Pf
Truncal lesions – not face
Don’t respond to antimicrobial
DDX superficial pyodermaMueller RS, Krebs I, Power HT, Fieseler KV Pemphigus Foliaceus in 91 Dogs. Journal of the American Animal Hospital Association: May/June 2006, Vol. 42, No. 3, pp. 189-196.
Deirdre F. Vaughan, E. Clay Hodgin, Giselle L. Hosgood, Joseph A. Bernstein: Clinical and histopathological features of pemphigus foliaceus with and without eosinophilic infiltrates: a retrospective evaluation of 40 dog
The importance of cellular infiltrates in tissues has been investigated as a diagnostic tool, mechanism of pathogenesis, and prognostic indicator in certain human diseases. Eosinophils, in particular, have a distinct role in the development of cutaneous lesions in human autoimmune diseases. Identification of an eosinophilic infiltrate can aid the diagnosis of immunobullous disease in the early stages of the disease process. In canine pemphigus foliaceus, eosinophils are present to a variable degree within lesional tissue. This study retrospectively evaluated 40 dogs with pemphigus foliaceus, and examined clinical and histologic features and final outcomes in cases with and without eosinophilic infiltrates. Twenty-five of 40 dogs (63%) had an eosinophilic infiltrate in either the pustules ⁄ crust, follicular infundibulum or dermis. There was no statistically significant difference in clinical distribution or appearance of dermatological lesions, response to treatment, or disease outcome in dogs with or without an eosinophilic infiltrate. However, dogs with concurrent disease were significantly more likely to have an eosinophilic infiltrate (P = 0.01). Dogs with adverse effects associated with immunosuppressive therapy were significantly more likely to have an eosinophilic infiltrate (P = 0.05). Fifteen of 40 dogs (38%) had a history of allergic disease and a significantly higher proportion of these dogs had an eosinophilic infiltrate (P = 0.04). An eosinophilic infiltrate was found in more than half of the dogs in this study. These findings justify further studies to investigate the role of eosinophils in the pathogenesis, therapy and prognosis in dogs with pemphigus foliaceus.Pemphigus foliaceus (PF) is the most common canine autoimmune skin disease. In contrast to human PF (hPF), desmoglein-1 is a minor autoantigen in the canine disease. The major autoantigen(s) of canine PF (cPF) remain(s) unknown, which limits the ability to perform mechanistic studies of lesion formation and the development of novel diagnostic and therapeutic strategies for this disease. The immunofluorescence patterns of selected desmosomal (desmoglein-1, desmoglein-3, desmocollin-1, desmocollin-3, desmoplakin-1/2, plakoglobin and plakophilin-1) and nondesmosomal adhesion proteins (E-cadherin, claudin-1, zona occludens-1 and occludin) in healthy canine footpad, haired skin and buccal mucosal epithelia were determined using hPF and pemphigus vulgaris sera and specific antibodies. The immunostaining patterns were then compared with that of indirect immunofluorescence staining with 66 cPF sera. Most cPF sera (58 of 66; 88%) exhibited positive staining along keratinocyte margins in the stratum spinosum and stratum granulosum of canine footpad. One serum contained autoantibodies binding solely to stratum granulosum keratinocytes. Concurrent intercellular fluorescence in the stratum basale was limited to seven of 66 cPF sera (11%). Only 12 of 66 cPF sera (18%) also exhibited positive IF staining of the buccal mucosa. This study confirms the immunological heterogeneity of cPF immunoglobulin G autoantibodies. Moreover, the major indirect immunofluorescence staining pattern and the inability of most cPF sera to label the buccal mucosa closely matched that of desmocollin-1. These observations warrant further investigation of desmocollin-1 as a potential major cPF autoantigen.
Pemphigus foliaceus (PF) is the most common antibody-mediated autoimmune skin disease of dogs. Desmoglein-1 (DSG1), the major human PF antigen, represents only a minor autoantigen in canine PF (cPF). A recent immunomapping study proposed desmocollin-1 (DSC1) as a relevant candidate autoantigen for cPF. To investigate this hypothesis, 85 cPF sera were screened for the presence of anti-DSC1 IgG using indirect immunofluorescence (IIF) on live canine DSC1-transfected 293T cells. Seventy-five sera contained detectable antikeratinocyte IgG on IIF using footpad substrate (IIFpos cPF), while 10 did not (IIFneg cPF). Sera from 35 healthy dogs, eight from exfoliative superficial pyoderma (ESP)-affected dogs and 21 dogs with non-PF autoimmune blistering skin diseases served as controls. All sera were tested concurrently by IIF on canine DSG1-transfected as well as nontransfected cells. None of the healthy dog or ESP sera labelled any of the transfected or nontransfected cells. Fifty-seven of 75 IIFpos cPF (86%) and 7/10 of IIFneg cPF sera (70%) contained detectable anti-DSC1 IgG. None of these sera recognized nontransfected cells. Five cPF sera (6%) recognized DSG1 in addition to DSC1. Finally, 5/21 (24%) sera from dogs with non-PF autoimmune blistering diseases contained low anti-DSC1 IgG titers. In 7/10 dogs (70%), from whom serial serum samples were collected during treatment, anti-DSC1 IgG titers decreased in parallel with the reduction in disease clinical severity. Altogether, these findings suggest that DSC1 is a major autoantigen in cPF.
Dariers disease
Like the human disease – early onset papular
Defective SERCA2 and have abnormal calcium regulation
4 to 8 weeks of age
Hyperplastic and crusting lesion on sternum, pressure points.
Suprabasal and intraepidermal
Lesions on elbows
Usually midepidermal
Hailey Hailey diseasePemphigus erythematosis (Dsg 1 - Desmosome)
Crossover between Pf and CLE
Superficial pemphigus
Pf and Pe
Superficial Necrolytic dermatitis (Vet Pathol 30:75)
Superficial necrolytic dermatitis is described in more detail as a keratinising defect.
Pv
P vegetans
Paraneoplastic pemphigusReview
Olivry T, Linder KE. Dermatoses affecting desmosomes in animals: a mechanistic review of acantholytic blistering skin diseases. Vet Dermatol. 2009 Oct;20(5-6):313-26.
Dariers disease too
Pemphigus vulgaris (Dsg 3 & 1)
Begins in mucus membranes
Pemphigus vegitans
Lesions at all levels of epidermis
Hyperplastic disease.
IgA Pemphigus (Desmocollin 1 Desmosome)
Is a combination of PV and EM
Oral cavity, vulva and spreads to skin
Elmore SA, Basseches J, Anhalt GJ, Cullen JM, Olivry T. Paraneoplastic pemphigus in a dog with splenic sarcoma. Vet Pathol. 2005 Jan;42(1):88-91.Epidermolysis bullosa simplex (Keratin 5 or 14)