Subcutaneous panniculitis-like T-cell lymphoma: Morphological, immunophenotypical and clonality assessment in six cats.

BACKGROUND: Primary cutaneous lymphoma represents 0.2%-3% of all feline lymphomas, with nonepitheliotropic lymphomas being the most common. In humans and dogs, subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a primary nonepitheliotropic lymphoma with a T-cell phenotype developing in the subcutis and often mimicking inflammation. OBJECTIVE: The aim of this report is to describe pathological, phenotypical and clonal features of SPTCL in cats. ANIMALS: Six cats with SPTCL were included in this study. MATERIALS AND METHODS: Skin biopsies were formalin-fixed, routinely processed and stained. Histological and immunohistochemical investigation for anti-CD18, CD204, CD79a, CD20, CD3, FeLVp27and FeLVgp70 and clonality assessment were performed. RESULTS: Four male and two female domestic shorthair cats, mean age 11.2 years, developed SPTCL in the abdominal (three), inguinal (two) and thoracic (one) regions. Variably pleomorphic neoplastic lymphoid cells were present in the panniculus in percentages, expanding the septa (six of six) and extending into fat lobules in one of six cats. Tumours were associated with elevated numbers of neutrophils (five of six), lesser macrophages (six of six) and variable necrosis (six of six). Neoplastic cells expressed CD3+ (six of six), with clonal T-cell receptor rearrangement detected in five of six cats. CONCLUSIONS AND CLINICAL RELEVANCE: This is the first description of SPTCL in cats. Lesions can be confused with panniculitis, leading to delay in diagnosis and therapy. Awareness of this neoplastic disease is relevant to avoid misdiagnoses and to gain greater knowledge about the disease in cats.

Common superficial and deep cutaneous bacterial infections in domestic animals: A review.

The skin covers the external surface of animals, and it is constantly exposed to and inhabited by different microorganisms, including bacteria. Alterations in the skin barrier allow commensal and/or pathogenic bacteria to proliferate and penetrate deep into the lower layers of the skin. Being the first barrier to the external environment, the skin is prone to injuries, allowing the penetration of microorganisms that may lead to severe deep infections. Companion animals, especially dogs, are prone to bacterial infections, often secondary to allergic dermatitis. When environmental conditions are unfavorable, horses, cattle, sheep, and goats can develop superficial infections, such as those caused by Dermatophilus congolensis. Deep inflammation is commonly caused by Mycobacterium spp., which results in granulomatous to pyogranulomatous dermatitis and panniculitis. Likewise, bacteria such as Nocardia spp. and Actinomyces spp. can cause deep pyogranulomatous inflammation. Bacteria that lead to deep necrotizing lesions (eg, necrotizing fasciitis/flesh-eating bacteria) can be severe and even result in death. This review includes an overview of the most common cutaneous bacterial infections of domestic animals, highlighting the main features and histologic morphology of the bacteria, cutaneous structures involved, and the type of inflammatory infiltrates.

Resolution of feline Mycobacterium panniculitis despite protracted treatment with methylprednisolone acetate.

Saprophytic or non-tuberculous mycobacteria are ubiquitous in the environment. They can cause opportunistic infections when the skin is broken and typically manifest with draining sinus tracts or cutaneous nodules. This report details the first confirmed Mycobacterium smegmatis panniculitis in a cat in South Africa. Despite repeated treatment with methylprednisolone acetate for six months prior to diagnosis, the cat made an uneventful recovery once switched to doxycycline and marbofloxacin.

Palisading granulomatous dermatitis and panniculitis (palisading granuloma) of dogs.

Palisading granulomatous dermatitis and panniculitis is recognized in various cutaneous inflammatory lesions secondary to presumed collagen damage. Cutaneous nodules with a palisading arrangement of histiocytes surrounding foci of collagen degeneration have been clinically termed palisading granuloma in dogs. Study aims were to characterize the cellular infiltrate of canine palisading granuloma and document salient clinical features. Inclusion criteria were met for 36 dogs and encompassed nodular dermal and subcutaneous histiocyte-predominant cellular infiltrates targeting and enveloping collagen fibers/necrotic foci with palisading configurations. Infectious causes were ruled out via standard histochemical stains and/or clinical data. Medical records were reviewed for signalment, clinical features, treatment, outcome, and comorbidities. Immunohistochemistry (IBA1, CD204, E-cadherin) and Masson's trichrome stain were used to assess histiocytic populations and dermal collagen, respectively. The histiocytes had moderate or strong immunolabeling for IBA1 and CD204 in 36/36 dogs (100%) and mild positive immunolabeling for E-cadherin in 3/36 dogs (8%). Alteration of collagen was graded as moderate or strong in 32/36 dogs (89%) and mild in 3/36 dogs (8%). Large breeds predominated with 30/36 dogs (83%) being ≥23 kg. Focal nodules were identified in 31/36 dogs (86%). The head/face were involved in 19/36 dogs (53%) and the extremities in 18/36 dogs (50%). Lesions from the 5/36 dogs (14%) with multiple nodules contained prominent eosinophilic infiltrates. Following excision, there was no evidence of recurrence. In conclusion, palisading granulomas are a distinct, non-neoplastic, histiocyte-predominant inflammatory condition in dogs associated with altered dermal collagen and favorable prognosis.

Mycobacterium setense isolated from a cat with atypical mycobacterial panniculitis.

Atypical mycobacterial panniculitis was diagnosed in a cat. Mycobacterium setense was identified as causative agent by 16 S rRNA gene sequence analysis. This a gram-positive rod-shaped acid-fast bacterium belonging to Mycobacterium fortuitum group was never reported before in diseased animals. Resistance to doxycycline and clarithromycin was detected. During treatment with pradofloxacin, additional resistance to fluoroquinolones developed which was due to a mutation in the gyrase gene gyrA (S90W exchange). Despite of antimicrobial treatment for 33 months the patient did not fully recover. Species identification and susceptibility testing for choosing adequate antimicrobial treatment is recommended in cases of feline mycobacterial panniculitis.

Pyogranulomatous panniculitis in a domestic cat associated with Pseudomonas luteola infection.

Pseudomonas luteola, a pathogen causing disease in humans, has in animals been reported only in rainbow trout and ferrets. This case report describes pyogranulomatous panniculitis in a cat associated with P. luteola infection. Organisms were seen histologically and identified with PCR and sequencing. Lesions resolved after treatment with marbofloxacin.

Pseudomonas luteola, un pathogène de l'homme, a été décrit chez l'animal seulement chez le furet et la truite arc en ciel. Ce cas clinique décrit une panniculite pyogranulomateuse chez un chat associée à une infection à P. luteola. Les organismes ont été vus à l'examen histopathologique et identifiés par PCR et séquençage. Les lésions se sont résolues après un traitement à la marbofloxacine.

Pseudomonas luteola, un patógeno que causa una enfermedad en los seres humanos, se ha reportado en animales solo en truchas arco iris y hurones. Este caso clínico describe una paniculitis piogranulomatosa en un gato asociada con una infección por P. luteola. Los organismos se observaron histológicamente y se identificaron mediante PCR y secuenciación. Las lesiones se resolvieron después del tratamiento con marbofloxacina.

Pseudomonas luteola é um patógeno causador de doença em humanos e, em animais, há relatos de sua ocorrência apenas em furões e trutas arco-íris. Este relato descreve um caso de paniculite piogranulomatosa em um gato associada à infecção por P. luteola. Os microrganismos foram observados histologicamente e identificados por PCR e sequenciamento. As lesões foram resolvidas após tratamento com marbofloxacino.

Nodular panniculitis in a cat with high alpha tocopherol concentration in serum.

A 5-year-old male neutered domestic shorthair cat suffered from recurrent solitary nodules in different subcutaneous body regions. Nodules were surgically removed and each time histopathological diagnosis was fat necrosis and fibrosing to pyogranulomatous panniculitis. After the second surgery the alpha (α)-tocopherol concentration in serum of the cat was examined and the result (21 mg/L) exceeded the upper limit of the reference interval (3-11 mg/L). Vitamin E amount in diet fed solely in the past was checked as studies have shown that vitamin E amounts in food significantly influence vitamin E concentrations in serum. For comparative purposes, α-tocopherol concentrations were determined in sera of healthy control cats. Additionally, vitamin E amount in wet food from different manufacturers was analysed using gas chromatography coupled to mass spectrometry (GC-MS). The results showed that the diet did not have higher vitamin E amounts compared to other diets. All control cats had similar high serum α-tocopherol concentrations. We conclude that panniculitis can occur despite high serum α-tocopherol concentrations in cats. Further studies are needed to redefine reference values of α-tocopherol in serum of cats.

Sterile traumatic panniculitis in a captive Brent goose.

A captive, adult female Brent goose (Branta bernicla) with a history of severe feather picking by its mate, was presented with 0.5-2.5 cm skin nodules on the head and neck. Histologic examination revealed a well-delineated dermal mass that surrounded an intact feather follicle and was composed of lakes of proteinaceous fluid and fibrin with scattered foamy macrophages and multinucleate giant cells. No bacteria or fungi were identified with histology, microbial culture, or PCR. Sterile panniculitis is an infrequent finding in animals and traumatic panniculitis is rarely sterile.

Mycobacterium porcinum causing panniculitis in the cat.

A 4-year-old domestic shorthair cat was presented with a 7-month history of nodules and draining fistulous tracts of the ventral abdomen. Histopathological examination of affected tissue revealed acid-fast bacilli stained by the Ziehl-Neelsen procedure. Deep tissue culture confirmed infection with a rapidly growing mycobacterium, and gene sequencing characterized the organism as Mycobacterium porcinum. Treatment with pradofloxacin and doxycycline resulted in clinical resolution of the lesions. On continued antibiotic therapy 7 months later, there was no local recurrence nor were there clinical signs associated with distant spread of the infection. This is the first clinical description of a feline infection with this organism. Key clinical message: This is the first clinical description of mycobacterial panniculitis in a cat due to genetically characterized Mycobacterium porcinum. This case report highlights a disease entity that can present a diagnostic and therapeutic challenge to clinicians.

Panniculite chez un chat causée par Mycobacterium porcinum . Un chat domestique à poil court âgé de 4 ans fut présenté avec une histoire d'une durée de 7 mois de nodules et de trajets fistulaires drainants à l'abdomen ventral. Un examen histopathologique des tissus affectés a révélé la présence de bacilles alcoolo-acidorésistants par coloration de Ziehl-Neelsen. Une culture des tissus profonds confirma l'infection par des mycobactéries à croissance rapide, et le séquençage génétique caractérisa l'organisme comme étant Mycobacterium porcinum. Un traitement avec de la pradofloxacine et de la doxycycline permit une résolution clinique des lésions. Sept mois plus tard, à la suite d'une antibiothérapie continue, il n'y avait aucune récurrence locale ni de signe clinique associé avec une dissémination de l'infection. Ceci est la première description clinique d'une infection féline associée à ce microorganisme.Message clinique important :Ceci est la première description clinique d'une panniculite à mycobactérie chez un chat associée à Mycobacterium porcinum caractérisé génétiquement. Ce rapport de cas met en évidence une maladie qui peut représenter un défi diagnostique et de traitement pour les cliniciens.(Traduit par Dr Serge Messier).

Sterile Pyogranulomatous Dermatitis and Panniculitis.

Canine sterile pyogranulomatous dermatitis and panniculitis is an infrequently described syndrome. No autoantigen, or exogenous antigen, inflammatory stimulus has been identified. This syndrome is characterized by pyogranulomatous nodules, plaques, and ulcers of variable extent and severity. Prodromal and concurrent nonspecific clinical and hematologic signs of inflammation may occur. This waxing and waning condition is typically responsive to systemic immunomodulation. Lifelong therapy may be required to prevent relapse. Differential diagnoses include bacterial and fungal nodular dermatoses, neoplasia, and cutaneous reactive histiocytosis. Diagnosis is achieved via diagnostic exclusion of infectious causes and supportive histopathology findings.

Detection of anti-neutrophil cytoplasmic antibodies in dogs with immune-mediated inflammatory diseases.

Anti-neutrophil cytoplasmic antibody (ANCA) is a type of autoantibody against neutrophil cytoplasm. In veterinary medicine, few studies have reported the detection of ANCA in dogs, and most of these studies were performed in dogs with inflammatory bowel disease (IBD). The aim of this study was to evaluate whether ANCA is detected in dogs with immune-mediated inflammatory diseases (IMIDs) other than IBD. Serum samples were collected before treatment initiation from 40 client-owned dogs with various diseases and 22 healthy beagle dogs; the dogs were classified into two groups: IMID group (n = 16) and control group (n = 46). ANCA was detected using the indirect fluorescent antibody test. Of the 16 dogs in the IMID group, 13 (81.3%) tested positive for ANCA. In contrast, of the 46 dogs in the control group, 13 (28.03%) tested positive for ANCA. Moreover, a significant association between ANCA positivity and IMIDs was identified in the IMID group than in the control group (P = 0.0003). In the control group, however, dogs with bacterial infection showed a relatively high rate of ANCA positivity. Therefore, ANCA positivity was observed in dogs with both IMIDs and bacterial infection. This suggested that ANCA positivity is associated with diseases accompanied by neutrophil activation and infiltration.

Subcutaneous Panniculitis-Like T-cell Lymphoma in Dogs: Morphologic and Immunohistochemical Classification.

Canine nonepitheliotropic cutaneous T-cell lymphomas (NECTCL) are poorly characterized. In humans, a number of distinct subtypes of NECTCL have been recognized, including subcutaneous panniculitis-like T-cell lymphoma (SPTCL). Five dogs with subcutaneous T-cell lymphomas histologically similar to SPTCL in humans are herein described. The mean age was 8.5 years (5.5 to 12 years). No breed or sex predilection was identified in this small cohort. Two dogs presented with an acute onset of multiple skin masses and 3 dogs had solitary masses with subsequent development of multiple smaller masses within 0.5 to 2 months post-diagnosis without treatment. Locations, when specified, included shoulder, neck, and ventral abdomen. Two dogs were euthanized following diagnosis and one dog treated with chemotherapy (CCNU) survived 7 months post-diagnosis. Histologically, all cases were characterized by proliferations of either small to intermediate or large sized, CD3-positive T cells that infiltrated the subcutis in a lace-like pattern and frequently rimmed adipocytes. No epitheliotropism was observed, neoplastic cells were often karyorrhectic, and there were regions of extensive necrosis. Heavy infiltrates of histiocytes with prominent phagocytosis masked the lymphoid neoplastic cell population in some sections. A clonal T-cell receptor gamma gene rearrangement was found in 4 of the 5 cases. While SPTCLs typically have a less aggressive clinical course in humans, their biological behavior in dogs remains to be determined. In summary, SPTCL may represent a distinct entity in dogs and needs to be accurately diagnosed to better determine clinical behavior.

Analysis of Bacterial and Fungal Nucleic Acid in Canine Sterile Granulomatous and Pyogranulomatous Dermatitis and Panniculitis.

Next generation sequencing (NGS) studies are revealing a diverse microbiota on the skin of dogs. The skin microbiota of canine sterile granulomatous and pyogranulomatous dermatitis (SGPD) has yet to be investigated using NGS techniques. NGS targeting the 16S rRNA and ITS-1 region of bacterial and fungal DNA, respectively, were used to investigate if bacterial and fungal DNA were associated with skin lesions in cases of canine SGPD. The study included 20 formalin-fixed paraffin-embedded (FFPE) skin samples and 12 fresh samples from SGPD-affected dogs, and 10 FFPE and 10 fresh samples from healthy dogs. DNA was extracted from deep dermis and panniculus, and microbial DNA was amplified using primers targeting the bacterial 16S rRNA V1-V3 and fungal ITS-1 regions. The amplified DNA was utilized for NGS on an Illumina MiSeq instrument. The sequences were processed using QIIME. No differences in fungal or bacterial alpha diversity were observed between the SGPD and control samples. Beta diversity analysis demonstrated differences in the bacterial communities between SGPD and control, but not in the fungal communities. Compared to controls, the family Erysipelotrichaceae and genus Staphylococcus were significantly more abundant in the SGPD FFPE samples, and genus Corynebacterium were more abundant in fresh samples. The bacteria found to be more abundant in SGPD are common inhabitants of skin surfaces, and likely secondary contaminants in SGPD cases. This study provides additional evidence that SGPD lesions are likely sterile.

Sterile nodular panniculitis with lung and lymph node involvement in a Siberian tiger (Panthera tigris altica).

A 2- to 4-year-old uncastrated male Siberian tiger (Panthera tigris altica) bred in a local wild animal park presented with generalized clinical signs including abdominal pain, fever, lethargy, and anorexia, along with subcutaneous nodules along the trunk. The patient subsequently died of chronic, progressive dyspnea despite 45 days of antibiotic treatment. At necropsy, mesenteric fat inflammation and multiple subcutaneous, peritoneal, and intraabdominal nodules were observed. The lungs demonstrated congestion and heavy coagulation, and necrotic foci were observed on the cut surface. Histopathologically, the nodules were identified as granulomatous fatty tissue with numerous lymphocytes, infiltration with lipid-laden macrophages, and fibrosis. These changes were also noted in the lung. The etiology of this condition remains undetermined.

Drug-induced panniculitis due to deworming in a dog ­ case report / Paniculite farmacodérmica decorrente de vermifugação em um cão - relato de caso

Outpatient clinics, clinics, and veterinary hospitals in the state of São Paulo and other Brazilian states commonly prescribe broad-spectrum vermicidal agents. The prescriptions are not based on coproparasitological examination results and drugs, including those used for the elimination of enteric parasites, are not innocuous and can potentially cause health hazards. Therefore, we report a clinical case of drug-induced panniculitis caused by deworming and show the actual occurrence of endoparasites in canine and feline outpatients at HOVET-USP.(AU)

É prática corrente em ambulatórios, consultórios, clínicas e hospitais veterinários paulistas, por não dizer brasileiros, a prescrição de ativos com ação vermicida, no senso lato, sem o embasamento do, hoje até prosaico, exame coproparasitológico. É sabido há muito que todo e qualquer fármaco não é inócuo e pode potencialmente acarretar agravos à saúde, e dentre estes incluem-se os ativos destinados à erradicação de parasitos entéricos. Decidiu-se assim por se relatar um caso clínico de paniculite farmacodérmica decorrente de vermifugação, bem como situar a real ocorrência de endoparasitas em pacientes, caninos e felinos, trazidos para atendimento ambulatorial no HOVET-USP.(AU)

Predictive Blood Chemistry Parameters for Pansteatitis-Affected Mozambique Tilapia (Oreochromis mossambicus).

One of the largest river systems in South Africa, the Olifants River, has experienced significant changes in water quality due to anthropogenic activities. Since 2005, there have been various "outbreaks" of the inflammatory disease pansteatitis in several vertebrate species. Large-scale pansteatitis-related mortality events have decimated the crocodile population at Lake Loskop and decreased the population at Kruger National Park. Most pansteatitis-related diagnoses within the region are conducted post-mortem by either gross pathology or histology. The application of a non-lethal approach to assess the prevalence and pervasiveness of pansteatitis in the Olifants River region would be of great importance for the development of a management plan for this disease. In this study, several plasma-based biomarkers accurately classified pansteatitis in Mozambique tilapia (Oreochromis mossambicus) collected from Lake Loskop using a commercially available benchtop blood chemistry analyzer combined with data interpretation via artificial neural network analysis. According to the model, four blood chemistry parameters (calcium, sodium, total protein and albumin), in combination with total length, diagnose pansteatitis to a predictive accuracy of 92 percent. In addition, several morphometric traits (total length, age, weight) were also associated with pansteatitis. On-going research will focus on further evaluating the use of blood chemistry to classify pansteatitis across different species, trophic levels, and within different sites along the Olifants River.

Canine sterile nodular panniculitis: a retrospective study of 39 dogs.

BACKGROUND: Canine sterile nodular panniculitis (SNP) is an inflammatory disease of the panniculus that is typically managed with immunomodulatory or immunosuppressive treatments. It has been reported to be a cutaneous marker of an underlying systemic disease. HYPOTHESIS/OBJECTIVES: To assess the presence or absence of concurrent systemic diseases associated with canine SNP and to document breed predispositions. ANIMALS: Thirty nine dogs presented to a veterinary teaching hospital from 1990 to 2012 which met inclusion criteria. METHODS: Inclusion in this retrospective study required a diagnosis of SNP via histopathological analysis and negative special stains for infectious organisms. Breed distributions of affected dogs were compared to all other dogs examined at this hospital during the study period. Correlations between the histological pattern of panniculitis and the histological presence of dermatitis, clinical presentation of lesions, dog breed and therapeutic outcomes were assessed. RESULTS: Australian shepherd dogs, Brittany spaniels, Dalmatians, Pomeranians and Chihuahuas were significantly over-represented, but correlations between inflammatory patterns of panniculitis and other histological and clinical factors were not identified. Based on the information available in medical records, 32 dogs (82.1%) had no concurrent systemic diseases identified. Four dogs had concurrent polyarthritis, which may be related to SNP through unknown mechanisms. CONCLUSIONS/CLINICAL IMPORTANCE: This study identified several novel breed predilections for SNP; it failed to find any clear correlations with associated systemic diseases other than polyarthritis. The histological inflammatory pattern of SNP does not predict therapeutic outcome.

Pyogranulomatous panniculitis in ferrets (Mustela putorius furo) with intralesional demonstration of Pseudomonas luteola.

One ferret (Mustela putorius furo) from Finland and two ferrets from Austria, aged 1-4.5 years and of both genders, were presented with pyogranulomatous subcutaneous inflammation affecting the inguinal, preputial and femoral regions, respectively. Histologically, microorganisms were detected within the lesions. The organisms had a capsule that stained positively by the periodic acid-Schiff reaction. Pseudomonas spp. were cultured from the lesions in two cases. In the third case, electron microscopy revealed a prokaryotic organism surrounded by an electron lucent matrix. 16S rRNA gene sequencing showed highest sequence homology to Pseudomonas luteola in all three cases. In combination with recent reports of pleuropneumonia in ferrets due to P. luteola infection, these cases might indicate a predisposition of ferrets for infection by these bacteria.