[show abstract][hide abstract] ABSTRACT: Ichthyoses comprise a heterogeneous group of genodermatoses characterized by abnormal desquamation over the whole body, for which the genetic causes of several human forms remain unknown. We used a spontaneous dog model in the golden retriever breed, which is affected by a lamellar ichthyosis resembling human autosomal recessive congenital ichthyoses (ARCI), to carry out a genome-wide association study. We identified a homozygous insertion-deletion (indel) mutation in PNPLA1 that leads to a premature stop codon in all affected golden retriever dogs. We subsequently found one missense and one nonsense mutation in the catalytic domain of human PNPLA1 in six individuals with ARCI from two families. Further experiments highlighted the importance of PNPLA1 in the formation of the epidermal lipid barrier. This study identifies a new gene involved in human ichthyoses and provides insights into the localization and function of this yet uncharacterized member of the PNPLA protein family.
[show abstract][hide abstract] ABSTRACT: Staphylococcal toxic shock syndrome (STSS) is a rare toxinic dermatosis recently described in dogs. In this syndrome, also reported in man, the toxin toxic shock syndrome toxin-1 (TSST-1) acts as a superantigen and triggers the massive release of lymphocytic cytokines (IL 1, IL6, TNFα). Two cases are described in a Golden Retriever and a Maltese bichon who presented with a sudden onset of painful skin lesions. Clinical signs were characterised by a severe fever and generalised erythematous lesions and, rapidly a massive epidermal necrolysis (Nikolski sign positive). A bacteriological culture demonstrated the presence of coagulase-positive staphylococci, Staphylococcus pseudintermedius. Massive epidermal neutrophilic exocytosis, apoptotic keratinocytes and neutrophilic satellitosis were observed in skin biopsies. A severe superficial epidermal and infundibular necrosis was noted. In one case, dermatological lesions were associated with an uterine infection. This dog died two days later. In the second case, cutaneous lesions resolved within 3 weeks. The initial treatment included antibiotics, non-steroidal anti-inflammatories and opioid analgesia, intravenous rehydration, enteral nutrition and antiseptic bathing. Two years later, no relapse had occurred.
Pratique Médicale et Chirurgicale de l'Animal de Compagnie. 01/2012; 47(3):73–80.
[show abstract][hide abstract] ABSTRACT: Granulomatous sebaceous adenitis (GSA) is a rare idiopathic inflammatory disease due to the destruction of sebaceous glands. No sex predisposition is described but young adults are predisposed. Akita Inu, Standard Poodles, Samoyede, Havanese and Vizsla breeds are at higher risk. A hereditary autosomal recessive mode of transmission is strongly suspected for Poodles and Akitas. Currently pathogenesis is unknown but various causes have been suggested in the literature: autoimmune disease, hereditary keratinisation defect, lipid metabolism abnormality. Therapy involves the regular and repeated use of antiseborrheic topical agents such as ketaroplastics, keratolytics, moisturisers, propylene glycol, olive oil. If topical therapy alone is not effective the use of systemic agents may be needed. Various options have been proposed: essential fatty acids, vitamin A, retinoids and recently ciclosporin A. However no treatment is well defined, some adverse effects may occur with the use of systemic agents and results are inconsistent. No study is available demonstrating a clear benefit of systemic agents compared to topical ones.
Pratique Médicale et Chirurgicale de l'Animal de Compagnie. 01/2012; 47(3):65–71.
[show abstract][hide abstract] ABSTRACT: The human Sweet's syndrome is a polymorphic dermatosis including papules, pustules, vesicles, plaques and painful nodules. An acute onset, extracutaneous signs like pyrexia, respiratory or bowel disease and elevated neutrophil count are classical features. Histopathological changes, consisting predominantly of mature neutrophils typically located in the upper dermis, are the key of the diagnosis even they are not specific. We describe two canine cases with clinical biological histopathological signs looking like Sweet's syndrome.
Pratique Médicale et Chirurgicale de l'Animal de Compagnie. 01/2012; 47(4):119–127.
[show abstract][hide abstract] ABSTRACT: A retrospective study of 16 cases of dermatophytosis due to Microsporum persicolor in dogs is reported. Hunting dogs were overrepresented (12/16). Skin lesions were observed on the face in all cases, but also on other locations (limbs, neck). The lesions included alopecia (15/16), erythema (13/16), scales (14/16), and crusts (13/16). Histopathology was performed in 10 cases and showed folliculitis and a lichenoid interface dermatitis. Fungal culture was positive in all cases and clinical resolution was achieved with standard antifungal agents (enilconazole, ketoconazole, griseofulvin). Two recurrences were observed (new contacts with rodents).
The Canadian veterinary journal. La revue veterinaire canadienne 04/2011; 52(4):385-8. · 0.77 Impact Factor
[show abstract][hide abstract] ABSTRACT: Metastatic calcinosis associated with chronic renal failure and multiple urinary tract abnormalities was diagnosed in a 6-month-old Brittany spaniel that was presented with calcinosis cutis. This case report highlights the importance of skin as an indicator of systemic disease. The aetiopathogenesis of the four main types of tissue calcification is defined and discussed with an emphasis on metastatic calcinosis.
[show abstract][hide abstract] ABSTRACT: Straelensiosis is a newly described acariasis resulting from the pathogenic action of a parasitic larva of the family Leewenhoekiidae, Straelensia cynotis, which becomes temporarily encysted in the hair follicles. Several epidemiological aspects of this condition remain unknown. No cases of transmission to humans have been reported. Foxes and other small mammals are the usual hosts for these larvae; dogs are accidental hosts who suffer from a violent reaction with cysts at the fixation point. Cases are regularly reported in the South West and the South East of France, especially in hunting dogs and terriers. The cutaneous symptoms are a sudden, violent and very painful skin eruption with numerous crusted and bloody erythematous papules, on the dorsal line of the body and the lateral side of the members. These larvae can be revealed by deep incisive scraping of the papules. The histopathological examination of skin biopsies is also a means of diagnosis. The encystment of these larvae is temporary, on average 5 months after the initial infestation. Few acaricidal treatments are effective; only amitraze in a solution at 0.05 à 0.1%, excluding AMM, applied every 5 days for one month, may prove to be effective but improvement is very slow with a reduction in the number of nodules in 1 to 3 months. The prevention of this condition seems difficult.
Pratique Medicale Et Chirurgicale De L Animal De Compagnie - PRAT MED CHIR ANIM CIE. 01/2011; 46(1):3-8.
[show abstract][hide abstract] ABSTRACT: The authors make recommendations for the optimal use of topical glucocorticoids in routine practice based on their experience in canine dermatology and evidence from the literature. The rationale behind the use of topical glucocorticoids is reminded, as are the main factors to consider in the selection of the appropriate product from current therapeutic armamentarium, taking into account notably the anti-inflammatory power and side effects of glucocorticoid compounds, their percutenous penetration and absorption, as well as available veterinary presentations. The specific circumstances and instructions for use of topical glucocorticoids are developed in each of their main indications (atopic dermatitis, flea allergy dermatitis, pyotraumatic dermatitis, contact dermatitis, auto-immune dermatitis, perianal fistulas), as are reminded the limits to their use and potential side effects, underlining the need for proper education of the owner and good therapeutic monitoring of the patient.English VersionEnglish VersionEnglish Version
Pratique Medicale Et Chirurgicale De L Animal De Compagnie - PRAT MED CHIR ANIM CIE. 01/2011; 46.
[show abstract][hide abstract] ABSTRACT: In humans and dogs, atopic dermatitis (AD) is associated with immediate and late-phase hypersensitivity reactions directed against environmental allergens. Misoprostol, a prostaglandin E1 analogue, has recently proved useful in selectively inhibiting the allergen-induced late-phase reaction (LPR) in atopic humans. Our objectives were to determine whether misoprostol monotherapy might be effective in decreasing pruritus and clinical signs in dogs with uncomplicated AD. Of 20 dogs entered, 18, receiving misoprostol (6 μg/kg three times daily) as sole treatment for 30 days, completed the study. Posttreatment lesional and pruritus scores were significantly lower than pretreatment values (P < 0.0001). A reduction of more than 50% in the lesional and pruritus scores was observed in 61% and 56% of the dogs, respectively. Adverse effects consisted of mild intermittent vomiting and diarrhea. The present study suggests that LPR inhibitors may be effective in canine AD. These results need to be confirmed in future blinded, placebocontrolled clinical trials.
[show abstract][hide abstract] ABSTRACT: We described epidemiological, clinical, histopathological and ultrastructural features of ichthyosis in the golden retriever breed in a prospective study. We also investigated the mode of transmission of this disease.
We examined 150 golden retrievers, 73 of which were affected by ichthyosis (35 males and 38 females). We carried out detailed clinical and histopathological examinations for 40 affected dogs. Transmission electron microscopy was performed for two of them. We used pedigree analysis with the Cyrillic software to determine the mode of transmission.
Dermatological signs included a mild to moderate or severe generalised scaling with initially small to large whitish scales and progressively blackish scales. The ventral glabrous skin was hyperpigmented and rough, similar to sandpaper. Histopathological features were characterised by moderate to severe laminated or compact orthokeratotic epidermal hyperkeratosis without significant involvement of the stratum granulosum. Ultrastructural findings revealed laminated or compact keratin layers and numerous persistent corneodesmosomes within the stratum corneum. Analysis of the pedigree suggested an autosomal recessive inheritance.
The histopathological and ultrastructural characteristics strongly suggest that golden retriever ichthyosis is a retention ichthyosis, caused by absence of corneodesmosomal degradation, transmitted through an autosomal recessive mode.
Journal of Small Animal Practice 06/2009; 50(5):227-35. · 1.18 Impact Factor
[show abstract][hide abstract] ABSTRACT: OBJECTIVES: We described epidemiological, clinical, histopathological and ultrastructural features of ichthyosis in the golden retriever breed in a prospective study. We also investigated the mode of transmission of this disease. MATERIALS AND METHODS: We examined 150 golden retrievers, 73 of which were affected by ichthyosis (35 males and 38 females). We carried out detailed clinical and histopathological examinations for 40 affected dogs. Transmission electron microscopy was performed for two of them. We used pedigree analysis with the Cyrillic software to determine the mode of transmission. RESULTS: Dermatological signs included a mild to moderate or severe generalised scaling with initially small to large whitish scales and progressively blackish scales. The ventral glabrous skin was hyperpigmented and rough, similar to sandpaper. Histopathological features were characterised by moderate to severe laminated or compact orthokeratotic epidermal hyperkeratosis without significant involvement of the stratum granulosum. Ultrastructural findings revealed laminated or compact keratin layers and numerous persistent corneodesmosomes within the stratum corneum. Analysis of the pedigree suggested an autosomal recessive inheritance. CONCLUSION: The histopathological and ultrastructural characteristics strongly suggest that golden retriever ichthyosis is a retention ichthyosis, caused by absence of corneodesmosomal degradation, transmitted through an autosomal recessive mode.
Journal of Small Animal Practice 01/2009; 50(5):227-235. · 1.18 Impact Factor
[show abstract][hide abstract] ABSTRACT: Gene transfer represents the unique therapeutic issue for a number of inherited skin disorders including junctional epidermolysis bullosa (JEB), an untreatable genodermatose caused by mutations in the adhesion ligand laminin 5 (alpha3beta3gamma2) that is secreted in the extracellular matrix by the epidermal basal keratinocytes. Because gene therapy protocols require validation in animal models, we have phenotypically reverted by oncoretroviral transfer of the curative gene the keratinocytes isolated from dogs with a spontaneous form of JEB associated with a genetic mutation in the alpha3 chain of laminin 5. We show that the transduced dog JEB keratinocytes: (1) display a sustained secretion of laminin 5 in the extracellular matrix; (2) recover the adhesion, proliferation, and clonogenic capacity of wild-type keratinocytes; (3) generate fully differentiated stratified epithelia that after grafting on immunocompromised mice produce phenotypically normal skin and sustain permanent expression of the transgene. We validate an animal model that appears particularly suitable to demonstrate feasibility, efficacy, and safety of genetic therapeutic strategies for cutaneous disorders before undertaking human clinical trials.
Biochemical and Biophysical Research Communications 02/2006; 339(3):769-78. · 2.41 Impact Factor
[show abstract][hide abstract] ABSTRACT: Cutaneous lesions associated with internal diseases have become well-known in dogs, even if the circumstances in which they appear are not always known. They have a various clinic diversity which is related to the numerous internal diseases. Their knowledge is important since these cutaneous lesions appear in numerous differential diagnoses; some of them occur before the symptoms of the underlying disease. Finally, some constitute cutaneous paraneoplastic syndromes. The following diseases are considered: nodular dermatofibrosis, migratory necrolytic erythema, dermatomyositis, calcinosis cutis, cutaneous amyloidosis, cutaneous xanthomas, self-mutilation foot syndrome and syringohydromyelia syndrome.
[show abstract][hide abstract] ABSTRACT: Junctional epidermolysis bullosa (JEB) is a genodermatosis suitable for gene therapy because conventional treatments are ineffective. Here, we elucidate the genetic basis of mild JEB in a breed of dogs that display all the clinical traits observed in JEB patients. The condition is associated with reduced expression of laminin 5 caused by a homozygous insertion (4818+207ins6.5 kb) of repetitive satellite DNA within intron 35 of the gene (lama3) for the laminin alpha3 chain. The intronic mutation interferes with maturation of the alpha3 pre-messenger RNA resulting in the coexpression of a transcript with a 227 nucleotide insertion and a wild-type mRNA that encodes scant amounts of the alpha3 polypeptide. Our results show that the amino acid sequence and structure of the canine and human alpha3 chain are highly conserved and that the reduced expression of laminin 5 affects the adhesion and clonogenic potential of the JEB keratinocytes. These JEB dogs provide the opportunity to perform gene delivery in a naturally occurring genodermatosis and to evaluate host tolerance to recombinant laminin 5.
Journal of Investigative Dermatology 04/2005; 124(3):530-5. · 6.19 Impact Factor
[show abstract][hide abstract] ABSTRACT: Feline demodicosis is rarely reported compared to canine demodicosis. The objective of this report was to describe a retrospective study of 12 cases of feline demodicosis. Neither sex nor breed predisposition were observed. The age of diagnosis was between 5 months and 13 years. Demodex cati was identified in nine cases and Demodex gatoi in three cases. Cutaneous lesions were localized in 10 cases, generalized in two cases, and present on the face (8 cases), neck (5), shoulders (1), trunk (2) and limbs (1). Pruritus was mild in four cats and moderate in two cats. Dermatological lesions were characterized by alopecia (10 cases), erythema (7), scaling (4), erosions (4), ulcers (2), crusts (2), comedones (2), seborrhea oleosa (2), papules (1), pustules (1) and hyperpigmentation (1). Ceruminous otitis was noted in two cats. Pyoderma was noted in four cases. An underlying disease was identified in eight cats: FeLV infection (two cats), FIV infection (two cats), FeLV/FIV infections (one cat), diabetes mellitus (one cat), iatrogenic Cushing's syndrome (one cat), and diabetes mellitus associated with iatrogenic Cushing's syndrome (one cat). In two cats, an infestation by Demodex cati was identified at lesional sites of multicentric squamous cell carcinoma in situ. Different drugs were used in nine cases: crotamiton (two cases), amitraz (six cases), milbemycin oxime (one case). Therapeutic results were variable and related to the underlying disease.Funding: Self-funded.
[show abstract][hide abstract] ABSTRACT: Hereditary junctional epidermolysis bullosa (JEB) is a rare mechanobullous disease associated with defective expression of the hemidesmosome/anchoring filament proteins laminin-5, collagen XVII and integrin α6β4. The condition is characterized by extensive blistering of the skin caused by splitting of the lamina lucida of the basement membrane (BM) in the squamous epithelia and by extracutaneous manifestations. Congenital JEB has been sporadically reported in cattle, but the BM protein associated with the genetic defect has not been identified. We report a case of spontaneous JEB in a 2-week-old female Charolais calf. Clinical lesions observed at birth were acral, auricular and oral erosions and ulcers, and onychomadesis of the four feet. General signs included anorexia, apathy, emaciation and marked cutaneous pain that justified rapid euthanasia. Histopathological examination revealed a dermo-epidermal separation of the BM zone without keratinocyte cytolysis. Antigen immunomapping of frozen skin sections using antibodies to the major components of the human cutaneous BM revealed an intralamina lucida cleavage of the skin, which confirmed the diagnosis of JEB. In skin samples from the affected calf and wild type controls, the immunoreactivity of laminin-5 and collagen XVII was comparable, while expression of integrin α6β4 was strongly reduced in the proband. These are the first results identifying itgα6 and itgβ4 as the candidate genes affecting cattle in JEB. They also suggest that altered expression of integrin α6β4 in ruminants is not associated with pyloric atresia – a complication always observed in humans suffering from altered synthesis of integrin α6β4.Funding: Self-funded.
[show abstract][hide abstract] ABSTRACT: This report describes the use of cyclosporin in two cats with feline urticaria pigmentosa. A 20-month-old Sphinx female and a 6-month-old neutered Devon Rex male were referred with multiple erythematous macules and papules on the face, trunk and limbs. Some papules became progressively darker. Pruritus was severe in both cases. Histopathological examination of lesional biopsies showed a moderate to marked perivascular to diffuse infiltrate in the superficial and deep dermis. This infiltrate was comprised mainly of a homogeneous population of well-differentiated mast cells. The cats were treated with cyclosporin at 7.5 mg/kg orally once daily 2 h before meals. Within 4 weeks, there was on average 75% reduction in the initial lesions and pruritus. The treatment was discontinued for another 4 weeks. Cutaneous lesions were stabilized. Pruritus was mild. Thereafter, cyclosporin was continued on an alternate day regimen for 4 weeks and then every 3 days for another month. No adverse effects were noted. Cyclosporin was effective in the treatment of feline urticaria pigmentosa.Funding: Self-funded.
[show abstract][hide abstract] ABSTRACT: A 5-month-old female Brittany spaniel was presented with peracute crusting dermatitis. The dog had been treated with cephalexin for cystitis 6 weeks earlier. Systemic signs included hyperthermia, anorexia and dehydration. Dermatological signs were characterized by crusted and exudative lesions over the face, trunk and limbs. These lesions were very painful. Clipping revealed arciform and annular patterns. The periphery of these target lesions remained indurated and ulcerated. Histopathological features of lesional skin biopsies revealed a hydropic interface dermatitis with prominent single-cell apoptosis of keratinocytes at all levels of the epidermis and satellitosis of lymphocytes. Similar lesions were observed within the infundibular region of hair follicle outer root sheath epithelium. PCR tests (parvovirus, herpesvirus) performed from lesional biopsies were negative. Clinical and histopathological cutaneous lesions were compatible with erythema multiforme. Drug implication criteria showed the possible role of cephalexin. Symptomatic treatment (cleansing, antiseptic bathing, rehydration, antibiotics, morphine patch) was prescribed. Twenty-four hours later, the skin was particularly painful. A pustular dermatitis was observed over the entire body. These pustules were large and contained a yellowish material. Cytology revealed nondegenerative neutrophils and acidophilic acantholytic keratinocytes. Histopathological findings included subcorneal pustules containing nondegenerative neutrophils, acantholytic keratinocytes and few eosinophils. Clinical and histopathological cutaneous lesions were compatible with pemphigus foliaceus. Prednisolone (1 mg/kg twice daily, orally), antiseptic bathings and antibiotics (marbofloxacin) were prescribed for 3 weeks. Clinical improvement was then observed. The dose of prednisolone was tapered to an alternate-day regimen over 2 months. Cutaneous lesions completely disappeared. No relapse was observed for 4 years. The clinical succession, erythema multiforme and then pemphigus foliaceus associated with a cutaneous adverse drug reaction, is the main interest of this case.Funding: Self-funded.
[show abstract][hide abstract] ABSTRACT: Nodular dermatofibrosis is a genetic syndrome associated with multiple collagenous nevi and renal cystadenomas or cystadenocarcinomas in the German shepherd dog. We describe a retrospective series of 11 cases of nodular dermatofibrosis in this breed. The age of diagnosis varied from 7 to 12 years. Males were overrepresented (10 cases). The chief complaint was the presence of nodules (five cases), nodules associated with poor condition (four cases) and poor condition (two cases). Lesions were present on the head (11 cases) and limbs (nine cases). In one case, nodules were observed in the oral cavity. Cutaneous lesions were characterized as multiple cutaneous or subcutaneous nodules. The nodules were firm and sometimes depilated, hyperpigmented or ulcerated. General condition was affected in six cases: anorexia (four of six), emaciation (four of six), polyuria-polydipsia (three of six) and dehydration (three of six). Histopathological examination of nodules revealed areas of collagenous hyperplasia. Echography performed in seven cases demonstrated cystic and polylobulous structures in the kidneys. Four cases of cystadenomas and five cases of cystadenocarcinomas were confirmed by the histopathological examination of surgical or necropsy specimens from the kidneys. Euthanasia was considered either when the diagnosis was made (four of 11) or in the course of the following month (two of 11). In three cases, it was decided to remove the most damaged kidney. Two dogs survived for 9 months and another one survived over 1 year. In two cases, no surgery was performed and the dogs are still alive 12 months later.Funding: Self-funded.