Case report of canine discoid lupus erythematosus in Guatemala.

An 11-year-old male Golden Retriever was presented for consultation due to a chronic progressive lesion on the nose that had started a year before. The majority of the nasal mucosa was affected, with the disruption of the normal architecture, pigment atrophy and abundant peeling on the rostral plane. Histopathology revealed a band of lichenoid infiltrate at the interface and vacuolation of the cells in the basal layer consistent with a diagnosis of canine discoid lupus erythematosus.

Effective treatment of canine chronic cutaneous lupus erythematosus variants with oclacitinib: Seven cases.

BACKGROUND: The treatment of canine chronic cutaneous lupus erythematosus (CCLE) variants generally requires immunosuppression, which often results in potentially severe adverse effects. Janus kinase inhibitors, like oclacitinib, might be a valuable treatment option due to their rapid inhibition of the action of interferons known to be relevant in the pathogenesis of CCLE. OBJECTIVES: To report the efficacy and safety of oral oclacitinib for the treatment of canine CCLE variants. ANIMALS: Seven dogs were diagnosed with CCLE based on clinical signs and compatible histopathological findings. MATERIALS AND METHODS: Oclacitinib was administered at the induction dosage of 0.45 mg/kg twice daily to 1.8 mg/kg once daily. The response to treatment was graded as 'good' when there was ≥50% lesion reduction, or as 'complete remission' if all active lesions had resolved. Complete blood counts were performed at variable intervals. RESULTS: A complete remission of all lesions was obtained in the dog with exfoliative cutaneous lupus erythematosus, both dogs with mucocutaneous lupus erythematosus and three of four dogs with facial discoid lupus erythematosus (FDLE); a good response was seen in the remaining dog with FDLE. The first visible improvement of signs was seen within 2-to-3 weeks, while the time to complete remission was around 2 months. Clinical adverse effects were not seen, and haematological parameters remained within the reference range. CONCLUSIONS AND CLINICAL RELEVANCE: Oclacitinib may be considered an effective treatment option for different variants of canine CCLE.

Cutaneous polyautoimmunity in two unrelated dogs: pemphigus foliaceus and generalized discoid lupus erythematosus.

BACKGROUND: Polyautoimmunity, the concurrent expression of two or more distinct autoimmune diseases (ADs) in a single individual, is a known phenomenon in humans and has been rarely reported in dogs. To the best of the authors' knowledge, comorbid pemphigus foliaceus (PF) and generalized discoid lupus erythematosus (GDLE) has not been reported in dogs. HYPOTHESIS/OBJECTIVES: To describe the clinical, histological and immunological features and treatment outcome of two unrelated dogs with comorbid PF and GDLE. ANIMALS: One 10-year-old, spayed German shepherd dog and one 8-year-old, castrated American Staffordshire terrier presented for evaluation of a symmetrical, facial- and/or pedal-dominant pustular dermatitis with concurrent, truncal scaly plaques. METHODS: For each dog, clinicopathological characterization included physical examination, lesion cytological evaluation, bacterial culture and sensitivity testing, skin histopathological investigation and direct and indirect immunofluorescence testing. Additional diagnostic imaging and haematological testing was performed to exclude extracutaneous disease. RESULTS: Both dogs exhibited lesions clinically and histologically compatible with PF and GDLE. Moreover, one dog exhibited generalized leucotrichia and chronic superficial keratitis. Remission was achieved with immunosuppressive dosages of prednisolone [high-dose pulse (Case 1) or standard immunosuppressive dosage (Case 2)] and ciclosporin (5-6 mg/kg/day). Tissue-bound antikeratinocyte immunoglobulin (Ig)G and IgM were detected in both dogs. A weak basement membrane zone deposit of C3 was seen in one dog. Circulating antikeratinocyte and anti-desmocollin-1 IgG were detected in one dog. CONCLUSIONS AND CLINICAL IMPORTANCE: Cutaneous polyautoimmunity can occur in the dog. Depending on the specific disease combinations, overlapping clinical features may present diagnostic and/or therapeutic challenges. Moreover, these cases should be monitored for development of additional cutaneous or extra-cutaneous AD(s).

A retrospective study comparing histopathological and immunopathological features of nasal planum dermatitis in 20 dogs with discoid lupus erythematosus or leishmaniosis.

BACKGROUND: In areas endemic for leishmaniosis, discoid lupus erythematosus (DLE) and canine leishmaniosis (CanL) are the most common differential diagnoses for nasal planum erosive-ulcerative dermatitis in dogs. HYPOTHESIS/OBJECTIVE: To compare histopathological and immunopathological features of canine nasal planum erosive-ulcerative dermatitis with depigmentation due to DLE or CanL. ANIMALS: Nasal planum biopsies from dogs with nasal planum loss of architecture, depigmentation, swelling, erosions or ulcerations due to DLE (n = 14) or CanL (n = 6). METHODS: Sections of paraffin-embedded samples, stained with haematoxylin and eosin were reviewed. Samples were examined using antibodies targeting T cells (CD3), B cells (CD20), macrophages (Mac387) and class II major histocompatibility complex (MHC II). Histopathological and immunophenotypical findings were compared between DLE and CanL cases. RESULTS: Lichenoid and interface dermatitis were observed in both DLE and CanL cases. A nodular-to-diffuse, superficial and/or deep dermatitis with macrophages, lymphocytes and plasma cells was present only in CanL samples. CD20-positive cells predominated over CD3- and Mac387-positive cells in the two conditions. The percentage of dermal Mac387-positive cells was higher in CanL compared to DLE samples and the difference was statistically significant (P = 0.025). CONCLUSIONS/CLINICAL IMPORTANCE: In this study, similar histopathological and immunopathological findings were observed in dogs with nasal planum lesions due to DLE or CanL. Therefore, in areas endemic for leishmaniosis, the presence of the parasite should be investigated in canine nasal planum dermatitis showing clinical and histopathological features suggestive of DLE.

Clinical and microscopic features of generalized discoid lupus erythematosus in dogs (10 cases).

BACKGROUND: Generalized discoid lupus erythematosus (GDLE) is a newly recognized canine variant of chronic cutaneous lupus erythematosus (CLE) that is not well characterized. HYPOTHESIS/OBJECTIVES: We report herein the signalment, clinical signs, treatment outcome, histopathology and immunological findings of 10 dogs with GDLE. METHODS: Inclusion criteria were: (i) a >3 month history of generalized skin lesions indicating a chronic or recurrent nature; (ii) skin lesions resembling those of human GDLE; (iii) histopathology of CLE (lymphocyte-rich interface dermatitis). Direct immunofluorescence (IF) and antinuclear antibody serology were investigated whenever possible. RESULTS: Various breeds were affected in their mid- to late adulthood. Selection criteria of generalized multifocal, annular ("discoid") to polycyclic plaques with pigment changes, erythematous margin, adherent scaling, follicular plugging and central alopecia were shown in all dogs. In nine dogs, plaques contained mild to moderate central scarring with depigmentation and/or hyperpigmentation. There were no dogs in which the disease progressed to systemic lupus erythematosus within a median follow-up of 2.5 years. Per inclusion criteria, interface dermatitis occurred with basement membrane zone (BMZ) thickening, suprabasal apoptosis and/or dermal fibrosis in some dogs. Infundibular interface folliculitis was common; it sometimes transitioned to mural folliculitis in lower follicle segments, and occurred with follicular and sebaceous gland atrophy. The direct IF revealed patchy deposition of immunoglobulin IgG and IgM at the BMZ. Lesions responded to a variety of treatments, including ciclosporin, hydroxychloroquine, topical tacrolimus and tetracycline/niacinamide. Relapses were common after medications were tapered. CONCLUSIONS AND CLINICAL IMPORTANCE: These observations support the existence of a canine homologue of human GDLE.

Generalized canine discoid lupus erythematosus responsive to tetracycline and niacinamide therapy.

Discoid lupus erythematosus (DLE) is a commonly reported canine autoimmune disease that normally presents with a phenotype consisting of erythema, depigmentation, scaling, erosions/ulcers, and scarring over the nasal planum and the proximal dorsal muzzle. Recently, two cases of a generalized variant of this disease have been reported, whose lesions responded to either systemic glucocorticoids or a combination of topical corticosteroids, topical tacrolimus, and the oral antimalarial hydroxychloroquine. The purpose of this report is to describe an 11 yr old shih tzu that presented with skin lesions consisting of multiple annular, erythematous papules and plaques, hyperpigmentation, adherent scaling, and atrophic scars over the caudal dorsum, flanks, craniodorsal thorax, and lateroproximal extremities. A diagnosis of generalized DLE was made based on the clinical presentation, histopathology, laboratory values, and direct immunofluorescence findings. Treatment consisted of oral tetracycline and oral niacinamide, which resulted in complete remission of clinical signs. This is the first documented report of generalized canine DLE responding to the described immunomodulating regimen. Such a combination might therefore be considered as a glucocorticoid and/or antimalarial alternative for the management of generalized DLE.

Ciclosporin therapy for canine generalized discoid lupus erythematosus refractory to doxycycline and niacinamide.

BACKGROUND: Generalized discoid lupus erythematosus (DLE) is an autoimmune skin disease variant rarely reported in dogs. The antimalarial immunomodulator hydroxychloroquine has been suggested as maintenance therapy for generalized DLE in one dog, but several recurrences were noted in the 1 year follow-up of that patient. HYPOTHESIS/OBJECTIVE: To describe the effective treatment of generalized DLE with ciclosporin in one dog. ANIMAL: A 6-year-old, castrated male crossbred dog was presented with pruritic, well-demarcated annular to polycyclic, hyperpigmented plaques with marginal erythema on the dorsal head, neck, trunk and medial extremities; these had been nonresponsive to treatment with doxycycline and niacinamide. METHODS: Investigation included complete blood count, serum chemistry profile, urinalysis, serum antinuclear antibody test, histopathological examination and direct immunofluorescence testing of skin biopsies. RESULTS: The presence of lymphocyte-rich interface dermatitis on histology, together with generalized chronic recurrent hyperpigmented plaques, was consistent with the diagnosis of a generalized variant of DLE. The absence of systemic signs and unremarkable laboratory tests excluded concurrent systemic lupus erythematosus. Treatment was initiated with oral dexamethasone and ciclosporin. After 1 month, dexamethasone was discontinued and oral ketoconazole was added to the therapeutic regimen. Four months later, pruritus and erythema resolved, with most skin lesions becoming impalpable. Over the last 6 months, the patient's DLE was maintained in remission with oral ciclosporin and ketoconazole in combination every 3 days. CONCLUSIONS AND CLINICAL IMPORTANCE: The combination of ciclosporin and ketoconazole appeared effective to induce and maintain lesion remission in this dog with generalized DLE.

Bilaterally symmetrical alopecia with reticulated hyperpigmentation: a manifestation of cutaneous lupus erythematosus in a dog with systemic lupus erythematosus.

An adult castrated male Doberman Pinscher was presented with a 6-month history of well-demarcated alopecic patches with reticulated hyperpigmentation and fine peripheral scaling on the axillae, thorax, abdomen, inguinal region, and thighs. The dog later developed hyperthermia, lethargy, apparent joint pain, peripheral lymphadenomegaly, vomiting, and diarrhea. Relevant laboratory tests results included anemia, thrombocytopenia, proteinuria, and an elevated antinuclear antibodies serum titer. Histologically, skin biopsy specimens had a lymphocyte-rich interface dermatitis and interface mural folliculitis ending in follicular destruction. Altogether, these signs were consistent with a unique alopecic variant of chronic cutaneous lupus erythematosus, eventually associated with the development of systemic lupus erythematosus. This rare form of chronic cutaneous lupus needs to be added to the expanding list of lymphocyte-mediated autoimmune alopecias in dogs.

Successful treatment of a novel generalized variant of canine discoid lupus erythematosus with oral hydroxychloroquine.

Discoid lupus erythematosus (DLE) is a common canine autoimmune disease that usually manifests as a localized ulcerative and scarring nasal dermatitis. We report herein a generalized variant of canine DLE successfully treated with the antimalarial immunomodulator hydroxychloroquine (HCQ). A 9-year-old hairless Chinese crested dog was presented with annular and polycyclic hyperpigmented and scaly skin lesions with central erosions, hypopigmentation and/or scarring on the trunk, neck and lateral extremities. Associated systemic signs were not seen. The clinical diagnosis of generalized DLE was supported by the demonstration of lymphocyte-rich interface dermatitis with epidermal atrophy and dermo-epidermal deposition of immunoglobulins and activated complement. As for human DLE, treatment was initiated with HCQ at 5 mg/kg once daily along with 2 weeks of 0.1% tacrolimus ointment and restriction of sun exposure. Over the following year, complete remission was maintained with HCQ at 5 mg/kg orally once daily with the exception of three relapses; two occurred during treatment induction and the third arose when the frequency of HCQ administration was reduced to every other day. Disease flares were controlled with 0.1% tacrolimus ointment alternating with 0.1% prednicarbate cream once daily for 5-10 days. Altogether, adverse drug events were not seen with this regimen. In summary, clinically, histologically and immunologically, this dog's disease mirrored the generalized discoid variant of chronic cutaneous lupus erythematosus of humans. The apparent benefit of HCQ, its safety and low cost warrant future investigations of its use for treatment of canine cutaneous lupus variants.

Discoid lupus erythematosus (DLE) in a Spitz dog.

A 3-year-old, female Spitz, was presented due to lack of response to therapies with a 6-month history of skin lesions characterized by diffuse erythema and scaling on the dorsal trunk. Physical examination revealed the dog was active and healthy. Skin culture isolated no fungus. Histological examination of skin biopsy specimens revealed interface dermatitis with hydropic degeneration of the basal layers, predominant plasmacytic perivascular accumulation in the dermis, and intensive plasma cell-rich interface mural folliculitis. Moderate CD3-positive lymphocytes infiltrated the superficial dermis. This report may provide unique information of canine discoid lupus erythematosus in an unusual breed with atypical cutaneous lesions.

A case of interface perianal dermatitis in a dog: is this an unusual manifestation of lupus erythematosus?

Discoid lupus erythematosus (DLE) is a well-known autoimmune disorder described in dogs and humans. In dogs, DLE is considered the second most common immune-mediated dermatitis and is usually localized to the nasal planum. DLE does not evolve to generalized disease, however lesions may spread to the bridge of the nose and less commonly may extend to periocular region, pinnae, distal limbs, and mucocutaneous junctions (lips, oral cavity, and genital region). A 4-year-old male Bavarian Mountain Scenthound developed a chronic, erosive, cutaneous lesion located exclusively in the perianal region without facial skin involvement. Clinical signs included erythema, depigmentation, severe alopecia, crusting, and ulceration. Histologically, the hallmarks of the changes were an interface dermatitis consisting of plasma cells, lymphocytes, neutrophils, and macrophages, hydropic degeneration of basal cells, few apoptotic cells in the basal layer, pigmentary incontinence, and a focal thickening of the basement membrane, which was characterized by linear deposition of IgG. Despite the unusual localization the lesion was diagnosed as DLE based on the characteristic histologic and immunohistologic features. Following diagnosis, corticosteroid therapy resulted in a complete resolution of perianal lesions.

A retrospective study comparing the histopathological features and response to treatment in two canine nasal dermatoses, DLE and MCP.

Canine discoid lupus erythematosus (DLE) and mucocutaneous pyoderma (MCP) have overlapping clinical and histopathological changes, often making diagnosis difficult. Histopathological features of 27 nasal planum biopsies were scored to determine whether DLE and MCP were histopathologically distinguishable. Long-term follow-up, enabling assessment of clinical diagnoses, was available on 15 cases; 11/15 cases were immunomodulatory responsive (ImR) and 4/15 were antibiotic responsive (AbR). Clinical diagnosis, determined by response to treatment for 15/27 cases, was not predictable based on scoring of histopathological features. Distinct histopathological patterns were observed: 2/11 ImR cases had a lymphocyte-rich interface dermatitis. All other cases had the same histopathological changes: a band-like diffuse superficial plasmacytic to lymphoplasmacytic dermatitis +/- focal basal cell damage, but different clinical diagnoses (4/4 AbR, 9/11 ImR). German shepherd dogs/crosses were over-represented (44.4% of the cases) and tended to have more multifocal lesions (41.7% vs. 26.7% of all other breeds). Longer duration of disease was associated with a preponderance of plasmacytic infiltrate (P = 0.026).

Topical 0.1% tacrolimus for the treatment of discoid lupus erythematosus and pemphigus erythematosus in dogs.

Topical 0.1% tacrolimus was used for treatment of localized lesions associated with 10 cases of discoid lupus erythematosus (DLE) and two cases of pemphigus erythematosus (PE) either as a sole therapy (n=2) or as an adjunctive treatment (n=10). Eight of 10 dogs with DLE and both dogs with PE were improved following 8 weeks of topical application. In six of the eight dogs that improved, other medications were discontinued. No adverse effects in clinical or laboratory parameters were noted throughout the study.

Comparison of three monoclonal and three polyclonal antibodies in the immunohistochemical diagnosis of canine autoimmune skin diseases.

The aim of this study was to evaluate the utility of three monoclonal antibodies (mAbs), and two anticanine IgG and one anticanine IgM polyclonal antibodies (pAbs) for the immunohistochemical diagnosis of canine autoimmune skin diseases. Skin biopsies from 11 cases of pemphigus (7 foliaceus, 3 vulgaris and 1 erythematosus), 12 cases of discoid lupus erythematosus (DLE) and 12 cases of chronic hyperplasic dermatitis were used. The CA4E7 mAb (IgG1 + IgG2) showed similar sensitivity, but higher specificity and lower background than the two anti-IgG pAbs for the immunohistochemical diagnosis of pemphigus and DLE. The CA4F1 mAb (IgG2) and CA3H1 mAb (IgG2) showed moderate and low interepithelial reactivity, respectively, in autoimmune skin diseases, but strong staining of the cytoplasm of plasma cells of the inflammatory infiltrates. These results suggest that the CA4E7 mAb may be valuable in the immunohistochemical diagnosis of such disorders.

A canine case of discoid lupus erythematosus with circulating autoantibody.

A nine-year-old Shetland sheepdog was diagnosed as discoid lupus erythematosus by clinical features, histopathologic findings, positive direct immunofluorescence, negative antinuclear antigen test and the absence of multisystemic diseases. The indirect immunofluorescence test of this patient dog with the salt split skin showed the deposition at the bottom of the cleft at basement membrane zone (BMZ). Western immunoblotting revealed the 120 kDa and the 85 kDa proteins targeted by the autoantibody. These proteins did not correspond with the known BMZ component.

Investigation of antibodies to extractable nuclear antigens in dogs.

Determination of antibodies to specific nuclear antigens, termed extractable nuclear antigen (ENA), was investigated in healthy dogs and in dogs with autoimmune, inflammatory, and neoplastic diseases. Using a counterimmunoelectrophoresis method, the dogs' sera were tested for antibodies against the nuclear antigens single-stranded DNA, Sm, Ro, La, ribonucleoprotein, Scl, and proliferating cell nuclear antigen. Antibodies to the Ro antigen were found in 1 dog with discoid lupus erythematosus, in 1 dog with pemphigus erythematosus, and in 1 dog with facial pyoderma and chronic superficial keratitis. In 15 dogs, antibodies were detected to ENA, but the precipitin lines were too weak to identify the specific ENA. These antibodies were found in some dogs with systemic lupus erythematosus, discoid lupus erythematosus, pemphigus erythematosus, dermatomyositis, vitiligo, lymphoma; in the dog with facial pyoderma and chronic superficial keratitis; and in 1 healthy dog. The highest percentage of dogs with antibodies to ENA in a large series (greater than 8) of this study was in dogs with systemic lupus erythematosus (4 of 13; 31%).

Use of tetracycline and niacinamide for treatment of autoimmune skin disease in 31 dogs.

A combination of niacinamide and tetracycline was used to treat 31 dogs with various autoimmune skin diseases (discoid lupus erythematosus, pemphigus foliaceus, pemphigus erythematosus, and bullous pemphigoid). Of the 20 dogs with discoid lupus erythematosus, 70% had excellent or good response to treatment. Serious side effects were not noticed in any dog.

Recently described feline dermatoses.

This article discusses the etiology, clinical signs, diagnosis, and treatment of several diseases. Feline immunodeficiency, virus infection, cryptococcosis, dermatophyte pseudomycetomas, demodicosis, Sézary-like syndrome, and discoid lupus erythematosus in cats are reviewed.