Canine sterile nodular panniculitis: a retrospective study of 14 cases.

BACKGROUND: Sterile nodular panniculitis (SNP) is an uncommon inflammatory condition of subcutaneous fat that can be idiopathic, but has also been associated with underlying conditions such as pancreatic disease or systemic lupus erythematosus (SLE). The pathogenesis and clinical course of the condition are not well understood. OBJECTIVES: To retrospectively review cases of SNP associated with systemic signs, concurrent disease, or both and characterize the clinical, laboratory, imaging, and histopathologic findings, treatment, and response to treatment. ANIMALS: Fourteen dogs with histologically confirmed SNP diagnosed between 1996 and 2008. METHODS: Retrospective study. RESULTS: Skin lesions were ulcerated or draining nodules in 9 dogs and nonulcerative subcutaneous nodules in 5. Most dogs had systemic signs, such as fever, inappetence, lethargy, and multiple lesions. Common clinicopathologic findings included neutrophilia with or without left shift, increased alkaline phosphatase activity, mild hypoglycemia, hypoalbuminemia, and proteinuria. Concurrent diseases included pancreatic disease, SLE, rheumatoid arthritis, polyarthritis, lymphoplasmacytic colitis, and hepatic disease. Dogs responded to immunosuppressive doses of corticosteroids when administered. Prognosis for recovery was related to the underlying disease process. CONCLUSIONS AND CLINICAL IMPORTANCE: SNP is not a single disease. Rather, it is a cutaneous marker of systemic disease in many cases. After thorough evaluation for concurrent disease and infectious causes, immunosuppressive treatment is often effective.

Effects of silymarin on gossypol toxicosis in divergent lines of chickens.

Gossypol, a pigment of cotton, is a hepatic toxin for chickens. Thus, despite its high protein content, inclusion of cottonseed meal in poultry diets is problematic. Silymarin, an extract from milk thistle, has hepatoprotective qualities and could potentially serve as a feed additive to offset the toxicity of gossypol. The objective of this study was to determine if silymarin could counteract gossypol toxicosis. Cockerels (n = 144) from lines divergently selected for humoral immunity were used. Three individuals from each line were randomly assigned to a cage and fed a corn-soybean meal (control) diet for 14 d. Six cages per line were then randomly assigned 1 of 4 dietary treatments (1,000 mg/kg of gossypol, 1,000 mg/kg of silymarin, 1,000 mg/kg of both gossypol and silymarin, or a control diet). Body weight and feed intake data were collected for 21 d, with chickens bled weekly to collect plasma and determine hematocrits. Chickens were then killed, and livers were collected for subsequent histology and enzymatic activity analyses. Endpoints measured weekly were analyzed with repeated measures and regression methodologies. Plasma and liver enzyme activities, and histological measures, were analyzed using ANOVA. No significant interactions between diets and lines were observed. Chickens assigned to the gossypol and gossypol-silymarin diets stopped gaining weight at d 14 (P < 0.001) and lost weight by d 21 (P < 0.001). Gamma glutamyltransferase was also elevated in these chickens at d 14; activities increased further by d 21 (P < 0.001). Histological examination of liver slices indicated substantial lipidosis (P < 0.001). Furthermore, quinone reductase activity was higher in gossypol- and gossypol-silymarin-treated chickens than in control and silymarin-treated chickens (P < 0.001). Silymarin did not alleviate any clinical effects of gossypol toxicosis.

Idiopathic eosinophilic masses of the gastrointestinal tract in dogs.

BACKGROUND: Eosinophilic inflammation of the gastrointestinal tract of dogs occurs in numerous disorders, typically resulting in diffuse intestinal thickening. Rarely, eosinophilic masses have been reported. OBJECTIVE: Describe a series of dogs with 1 or more idiopathic eosinophilic gastrointestinal masses (IEGM) to better characterize the clinical features, treatment, and prognosis. ANIMALS: Seven dogs with 1 or more gastrointestinal masses composed primarily of eosinophilic infiltrates for which no underlying cause was found. METHODS: Retrospective case series. RESULTS: Rottweilers and purebred, large breed dogs predominated. Dogs were middle-aged and typically had chronic signs of upper or lower gastrointestinal disease. Decreased appetite, vomiting, and evidence of gastrointestinal hemorrhage were present in the majority of cases. An abdominal or rectal mass was frequently noted on physical examination. Common laboratory abnormalities included peripheral eosinophilia, mature neutrophilia, hypoproteinemia, and hypocholesterolemia. The masses were histologically composed of moderate to severe eosinophilic infiltrates, which were often transmural and accompanied by fibrosis. All dogs treated with surgery alone died of complications of their disease. Treatment with corticosteroids and ivermectin improved clinical signs, caused resolution of eosinophilic infiltrates, and prolonged survival in most dogs treated medically. CONCLUSIONS AND CLINICAL IMPORTANCE: These findings suggest that the prognosis for dogs with IEGM may be good when recognized and managed appropriately. When surgery is performed, medical treatment should also be added.

A histopathologic study of the effects of gossypol on the female rat.

The purpose of this study was to examine the tissues of female rats treated with gossypol acetic acid for morphologic evidence of an underlying mechanism of infertility. The number of estrous cycles, and body and adrenal weights were also compared. The number of estrous cycles decreased in rats treated with 60 mg/kg gossypol acetic acid for 30 days. Body weights were also reduced in rats treated with 40 mg or 60 mg/kg per day for 30 days when compared to controls. However, no significant differences were found in any group when comparing adrenal weights, adrenal weight/body weight ratios or adrenal histology. The body weight loss was related, at least in part, to diarrhea and dehydration in eight of the treated animals. It is interesting that though the gossypol-treated rats had reduced numbers of estrous cycles, no histopathologic changes were found in their ovaries, uterus or vagina.

Pulp remains viable following vital amputation of the mesio-buccal root of the maxillary fourth premolar in dogs.

Vital amputation of the mesio-buccal root of the maxillary fourth premolar (P4) was performed bilaterally in 8 dogs. Histopathologic evaluation of the tooth structure revealed normal pulp in the remaining mesio-buccal, mesio-palatal, and distal roots and crown during a mean follow-up period of 3.5 +/- 1.9 months. Amputation site healing was characterized by a reparative dentin bridge produced by odontoid cells. Tunnel defects were observed in 13 of 16 (81%) dentin bridges. It is concluded that the pulp of a tri-rooted, periodontal disease-free tooth remains viable during a 6-month period following vital root amputation. These results point to the intriguing possibility that this may also occur in humans, however, this needs to be directly tested in man.

Suspected citrus pulp toxicosis in dairy cattle.

Thirteen lactating dairy cows from a herd of 650 died over a 6-week period. Most animals were down in milk production at 1 milking and were found dead at the next milking. Two cows had elevated heart rate and enlarged mandibular lymph nodes. Two others had azotemia, elevated heart rate, hyperglycemia, and weight loss. Necropsy of 10 cows revealed hemorrhages on the intestinal serosa and epicardium, lymphadenopathy, interstitial nephritis, small intestinal hemorrhage, and interstitial pneumonia. Histopathology showed lymphocytic to lymphogranulomatous inflammation in the heart, spleen, kidney, lymph nodes, liver, lung, pancreas, and adrenal gland. Phlebitis was present in 2 livers. The lesions resembled those of hairy vetch toxicosis, but no vetch was being fed. Similar lesions have been reported with the feeding of citrus pulp. Citrus pulp was being fed to the lactating cows and had been added to the diet 6 weeks before the first death. The syndrome resolved with elimination of citrus pulp from the diet.

Malignant melanoma in a budgerigar (Melopsittacus undulatus).

A 3-year-old male budgerigar was presented for weakness. A 0.5-cm mass was located in the left patagium. Histologically, the mass was diagnosed as a malignant melanoma, previously unreported in budgerigars.

Tyzzer's disease in a neonatal cockatiel.

A 4-day-old cockatiel that died suddenly had a pale, mottled liver at necropsy. Extensive necrosis and numerous bacilli were present microscopically in the liver. The organism was identified as Bacillus piliformis, the causative agent of Tyzzer's disease, by special staining and electron microscopy. This is the first report of Tyzzer's disease in an avian species.

Neuronal-visceral GM1 gangliosidosis in Portuguese water dogs.

Three female siblings in a litter of seven Portuguese Water dogs (PWDs) showed clinical signs of ataxia and/or lameness at 5 months of age. Signs of cerebellar dysfunction (intention tremors, ataxia, widebased stance, dysmetria, and/or nystagmus) and mild limb weakness developed rapidly. Results of hemograms (three dogs), blood chemistry profiles (two dogs), urinalyses (two dogs), electroencephalograms (two dogs), and radiographs of the limbs or pelvis (three dogs), vertebrae (two dogs), and skull (one dog) were unremarkable except for an absolute lymphocytosis in one dog. Routine cerebrospinal fluid (CSF) analyses were normal in all three dogs. However, the CSF creatine kinase concentration was elevated in the one dog in which it was measured. Mucopolysacchariduria was present in all three dogs. Due to the rapid progression of clinical signs and a poor prognosis, all three dogs were euthanatized between 6 and 7 months of age. Histopathologic and electron microscopic studies showed neuronal cytoplasmic inclusions, vacuolated hepatocytes, and vacuolated renal tubular epithelial cells, compatible with the diagnosis of a storage disease. Beta-galactosidase activities in leukocytes, serum, and brain homogenates were reduced when compared with that in normal dogs and the stored product was identified as GM1 ganglioside, confirming GM1 gangliosidosis.

Endoscopic diagnosis of chronic hypertrophic pyloric gastropathy in dogs.

The endoscopic appearance of chronic hypertrophic pyloric gastropathy (CHPG) in five dogs is described. Several patterns of enlarged mucosal folds that surrounded and obstructed the pyloric canal were observed. Initially, endoscopically obtained biopsy samples of mucosa were judged to be histologically normal. Diagnosis of CHPG was confirmed and relief of pyloric obstruction accomplished at exploratory laparotomy (in four dogs). Retrospective evaluation of pyloric tissue samples, obtained during endoscopy, identified subtle histological characteristics of CHPG. Gastric and duodenal neoplasia or antral polyps can mimic the endoscopic appearance of CHPG but can be differentiated based on their endoscopic and histological appearance. These cases show that endoscopic examination is a valuable procedure for the diagnosis of CHPG in dogs that chronically vomit.

Twenty-four hour urinary protein loss in healthy cats and the urinary protein-creatinine ratio as an estimate.

Urinary protein loss was determined in 12 healthy cats. Voided urine was collected and protein quantitated by the Coomassie blue method. Mean protein loss for all cats was 12.65 mg/kg/24 h (5.45 SD). Protein loss for male cats (n = 6) was 16.62 mg/kg/24 h (3.3 SD), which was significantly different (P less than 0.01) from 8.69 mg/kg/24 h (4.09 SD) for females (n = 6). A single urine protein-creatinine ratio correlated well with the total urinary protein loss in mg/kg/24 h. The correlation coefficient for the protein-creatinine ratio in voided urine (UPCV) vs 24-hour urinary protein (UP-24) loss was 0.968, and that for the protein-creatinine ratio in urine obtained by cystocentesis (UPCC) vs UP-24 was 0.945. The regression equations were UPCV = 0.02145 + 0.02338 x UP-24 (mg/kg), and UPCC = 0.02667 + 0.02133 x UP-24 (mg/kg). Using the mean value plus 3 SD of urinary protein loss from the healthy cats in this study, a healthy cat would be expected to have a urinary protein loss of less than 29 mg/kg/24 h. A protein-creatinine ratio from a single urine sample provides an accurate estimate of urinary protein loss in healthy cats.

Prevention of cisplatin-induced nephrotoxicosis in dogs, using hypertonic saline solution as the vehicle of administration.

We determined whether administration of cisplatin in hypertonic saline solution would prevent significant decrease in renal function, as measured by exogenous creatinine clearance, in healthy dogs. A single dose of cisplatin (70 mg/m2 of body surface) was mixed in 3% saline solution and was infused IV (6.5 ml/kg of body weight) over a 20-minute period to 6 healthy dogs. Exogenous creatinine clearance was determined prior to treatment of dogs with cisplatin and again on days 3 and 21 after administration of cisplatin. All 6 dogs vomited at least once within 12 hours of treatment with cisplatin; however, clinically important changes in appetite, body weight, or hydration status were not apparent during the 21-day study. Although mean values for exogenous creatinine clearance decreased from baseline on days 3 and 21, changes were not significantly different. Renal histologic lesions included mild, chronic, lymphoplasmacytic interstitial nephritis in 5 dogs, and presumably, were unrelated to treatment with cisplatin. Mild renal tubular atrophy (n = 2) and tubular necrosis (n = 1) may have developed secondary to treatment with cisplatin. Results of this study indicated that administration of a single dose of cisplatin in 3% saline solution to healthy dogs was not associated with significant decrease in glomerular filtration rate. This is a convenient protocol for administering cisplatin; however, additional study is required before it can be recommended for clinical patients, especially those with preexisting renal disease or those receiving multiple doses of cisplatin.

Evaluation of the caudoventral portion of the mandible as a donor site for corticocancellous bone for periodontal surgery in dogs.

Corticocancellous bone graft was obtained from the caudoventral portion of the mandible of 8 dogs. The recipient site was an alveolar jugal and alveolar defect from vital root amputation of the mesiobuccal root of the maxillary fourth premolar. Anatomic observations of 20 canine cadavers indicated that guidelines for harvesting bone from the caudoventral portion of the mandible of dogs were the mesial aspect of the masseteric fossa, the distal aspect of the roots of the first mandibular molar, and the ventral aspect of the mandibular canal. The mean weight of corticocancellous bone harvested was 0.4 +/- 0.1 g. Harvested corticocancellous bone was adequate to fill recipient sites measuring a mean volume of 105.0 +/- 28.5 mm3. Histologic evaluation of the recipient site revealed progressive osseous integration of the bone-graft site during a mean follow-up period of 3.5 +/- 1.9 months. There was normal bone healing of the donor site without adverse effects on the mandibular molars or neurovascular structures of the mandibular canal. Vital amputation sites receiving silver amalgam had evidence of plasmacytic/lymphocytic inflammation associated with residual silver amalgam in the bone-graft area. The caudoventral portion of the mandible may be used as a donor site for autogenous corticocancellous bone in periodontal surgery of dogs.

Periodontal healing of canine experimental grade-III furcation defects treated with autologous fibrinogen and absorbable barrier membrane.

OBJECTIVE: To determine the effects of autologous fibrinogen (AF) and absorbable barrier membrane (ABM) on periodontal healing of canine experimental grade-III furcation defects. ANIMALS: 18 conditioned, laboratory-source, adult Beagles. PROCEDURE: Defects were developed bilaterally at the second and fourth premolars and maintained for 12 weeks. Defects were treated with AF, ABM, AF and ABM, or debridement. Digital subtraction radiography, histologic evaluation, and histomorphometric analysis of defect healing was done at 1, 3, and 6 months after treatment to determine percentage increases in bone volume, height, area, and length of periodontal regeneration along the perimeter of the defect. RESULTS: Comparison of defects at post-treatment intervals indicated significantly greater healing of debridement and AF-treated defects, compared with ABM-treated defects at 3 months; however, by 6 months, there were no significant differences in defect healing for all histomorphometric variables. Defects treated with ABM were associated with significantly less root ankylosis than other treatments. Defects treated with debridement had significantly greater increases in bone volume at 6 months after treatment, compared with groups treated with ABM. There was a significant correlation between regenerated bone area, bone volume, and periodontal regeneration for all treatments at 3 and 6 months after treatment. CONCLUSION AND CLINICAL RELEVANCE: Use of AF and ABM did not enhance the amount of periodontal healing, compared with debridement only. The ABM-treated defects were essentially devoid of root ankylosis. Grade-III furcation defects may respond equally well to conservative periodontal surgery or guided tissue regenerative techniques. The prevention of root ankylosis is a substantial benefit favoring this latter method of treatment.

Effect of left hepatic vein ligation on hepatic circulation, function, and microanatomy in dogs.

Eighteen healthy dogs were allotted to 3 groups (n = 6 dogs each). All dogs were evaluated at the beginning of the study by complete physical examination; total and differential WBC counts; serum biochemical analysis (alanine transaminase and alkaline phosphatase activities and bilirubin and albumin concentrations); sulfobromophthalein excretion, ammonia tolerance, and glucagon response testing; portal and intraparenchymal pressure determinations; operative mesenteric portography; and histologic assessment of hepatic biopsy specimens. The left hepatic vein was ligated completely in dogs of groups 1 and 2. Group-3 (control) dogs had a ligature placed loosely around the left hepatic vein. Dogs of groups 1 and 3 were reevaluated 24 hours after surgery by use of the aforementioned hematologic and biochemical tests. Group-1 dogs were reevaluated by use of portal and intraparenchymal pressure determinations, jejunal vein portography, and complete necropsy at 48 hours after surgery. At 4 weeks after surgery, dogs of groups 2 and 3 were reevaluated by use of all aforementioned tests. Results indicated transient hepatic congestion, which resolved by the fourth postoperative week. Longstanding effect on hepatic structure, circulation, or function was not found. We concluded that left hepatic vein ligation in clinically normal dogs does not cause severe or permanent liver damage.

Investigation of glomerular lesions in dogs with acute experimentally induced Ehrlichia canis infection.

Six male Beagles were inoculated with Ehrlichia canis. Transient proteinuria was confirmed during the acute phase of infection by serial determination of urinary protein-to-creatinine ratio. Peak urine protein loss, consisting principally of albumin, was observed 2.5 to 3.5 weeks after inoculation. Renal biopsy specimens were obtained before inoculation, during peak proteinuria, and 10 weeks after inoculation when proteinuria had resolved. Renal tissue was evaluated by use of light, immunofluorescent, and electron microscopy to correlate specific glomerular lesions with development of proteinuria. Histologic examination revealed perivenular and interstitial infiltrates of lymphocytes and plasma cells localized principally to the renal cortex. Glomerular lesions were minimal to absent. Immunofluorescent staining revealed moderate to marked deposition of anti-canine IgG and IgM in the glomerular tufts and mesangium. Depositions of anti-canine complement factor C3 were not observed. Immunofluorescent staining persisted 10 weeks after inoculation, despite resolution of proteinuria, and probably represented passive trapping of immunoglobulins. Ultrastructural examination revealed fusion of podocyte processes that coincided with development of proteinuria. Electron-dense deposits or changes in the basement membrane were not observed. Morphometric measurements of average podocyte process length and percentage of coverage of basement membrane by podocyte processes were used to quantify the degree of process fusion. Both measurements increased significantly (P < 0.05) during peak proteinuria, and returned to preinoculation values when proteinuria had resolved 10 weeks after E canis inoculation. These findings indicated possible minimal-change glomerulopathy, rather than immune-complex glomerulonephritis, during acute E canis infection and could explain transient proteinuria without histologic evidence of glomerular disease.

Effects of a prostaglandin E1 analogue, misoprostol, on renal function in dogs receiving nephrotoxic doses of gentamicin.

OBJECTIVE: To determine whether the prostaglandin E1 analogue, misoprostol, could preserve renal function in dogs receiving nephrotoxic doses of gentamicin. ANIMALS: 12 (6/group) healthy sexually intact male dogs. PROCEDURE: All dogs were given high doses of gentamicin (10 mg/kg of body weight, i.v., q 8 h, for 8 consecutive days). Six dogs (treatment group) received misoprostol (3 microgram/kg, p.o., q 8 h for the duration of the study) and 6 dogs (control group) received vehicle (1 capsule, p.o., q 8 h). Renal function was assessed before treatment (day 0) and on days 3, 6, 9, and 11 after initiation of treatment by measurement of serum biochemical variables, urine specific gravity, and exogenous creatinine clearance. Serum electrolyte and protein concentrations and presence of proteinuria, glycosuria, and cylindruria were also determined. At the end of the study, renal histopathologic changed were evaluated. RESULTS: Dogs receiving misoprostol had significant reduction in exogenous creatinine clearance with time, compared with dogs receiving vehicle (P = 0.0264). Dogs receiving misoprostol tended to develop more severe azotemia, hyperphosphatemia, and renal histopathologic changes; however, results were not significantly different between groups. CONCLUSION: Misoprostol (3 microgram/kg, p.o., q 8 h) did not preserve renal function and may have exacerbated gentamicin-induced nephrotoxicosis in this group of dogs. CLINICAL RELEVANCE: Supplementation of vasodilatory prostanoids may exacerbate renal dysfunction in dogs receiving high doses of gentamicin.

Primary spinal cord lymphosarcoma in a dog.

Primary lymphosarcoma of the spinal cord has been infrequently reported. This tumor was classified as intramedullary, the least common type of spinal cord tumor. The dog had rapid onset of paresis and paralysis, with no sign of spinal pain.

Metastatic extramedullary plasmacytoma of the colon and rectum in a dog.

Stage-3 extramedullary plasmacytoma of the large intestine was diagnosed in an 8-year-old Labrador Retriever. Three primary tumors were located in the colon and rectum, with metastasis to local lymph nodes and the spleen. The disease was associated with a monoclonal serum protein spike identified as IgG. Treatment consisted of surgical excision followed by chemotherapy, using melphalan and prednisone. The dog remained free from clinical signs of disease and adverse effects of the chemotherapy at 9 months. Findings in this dog indicated that extramedullary plasmacytoma may be an aggressive disease, associated with spread to distant sites and monoclonal gammopathy.

Evaluation of three fixation techniques for repair of mandibular fractures in dogs.

Bilateral midbody hemimandibular osteotomies were performed between premolars 3 and 4 in 18 adult dogs. Hemimandibles were repaired by use of monocortically applied bone plates (n = 6), an interdental fixator composed of an Erich arch bar and acrylic (n = 6), or a type I external skeletal fixator (n = 6). At the immediate postoperative evaluation, hemimandibles stabilized with interdental fixators had an osteotomy gap distance (mean +/- SEM, 1.6 +/- 0.2 mm) that was significantly (P < 0.05) greater than for hemimandibles stabilized with external skeletal fixators (1.2 +/- 0.3 mm). Osteotomy gap distance of hemimandibles stabilized with external skeletal fixators (1.5 +/- 0.2 mm) was significantly (P < 0.05) greater at weeks 4 (1.1 +/- 0.2 mm) and 8 (0.8 +/- 0.3 mm) after surgery than the osteotomy gap distance of hemimandibles stabilized by application of bone plates. By week 16, significant differences in osteotomy gap distance were not detected between groups. Immediately after surgery, mandibular alignment measurements were not significantly different for dogs with bone plates (0.3 +/- 0.1 mm), interdental fixators (0.3 +/- 0.1 mm), and external skeletal fixators (0.9 +/- 0.5 mm). Mandibular alignment scores were not significantly different between treatment groups during the remaining postoperative period. Occlusal measurements were not significantly different between evaluations performed before surgery and 16 weeks after surgery, regardless of treatment group. Radiographic evidence of healing in hemimandibles stabilized with external skeletal fixators was significantly (P < 0.05) less at 4 and 8 weeks, compared with hemimandibles stabilized with bone plates and interdental fixators; however, radiographic evidence of bone healing was not significantly different between fixation groups at 16 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)