Preliminary clinical observations on the use of piroxicam in the management of rectal tubulopapillary polyps

Rectal tubulopapillary polyps were diagnosed in eight dogs following proctoscopy and mucosal pinch biopsy. Histological examination of the pinch biopsies revealed evidence of malignant transformation in three of the cases. The remaining cases were diagnosed as benign polyps. Inflammatory changes were observed in four cases. Seven dogs were treated with piroxicam suppositories and one with oral piroxicam. All dogs were re-examined after four to six weeks of piroxicam therapy and the extent of haematochezia, tenesmus and faecal mucus production was reduced in all cases. The owners of seven of the dogs considered the improvement in clinical signs to be good or excellent. Cases with and without evidence of inflammation responded equally well. This finding supports the hypothesis that piroxicam has an antineoplastic effect due to apoptosis and alteration in the cell cycle. Medical management with piroxicam may provide a non-invasive treatment option for dogs with rectal polyp formation in which surgical treatment is likely to be associated with complications such as incontinence, infection and wound breakdown, or where the owner declines such treatment.     

Peritoneal fluid values from healthy foals

Peritoneal fluid was analysed from 17 foals, aged 13 to 134 days with a mean age of 68 days. Cytologically, the peritoneal fluid was characterised by a mean total cell count of 0.45 x 10(9)/litre (range 0.06 to 1.42 x 10(9)/litre), rare eosinophils, rare cytophagia and variable percentages of neutrophils and mononuclear cells. These data indicate that peritoneal fluid nucleated cell counts over 1.50 x 10(9)/litre in the foal should be interpreted as elevated. Biochemical evaluation revealed a mean biuret protein level of 12 g/litre, mean refractive index protein level of 16 g/litre and urea nitrogen concentration of 1.96 mmol/litre. There was no correlation between the foals' white blood cell and peritoneal fluid nucleated cell counts. Results of this study indicate that adult horse reference values for evaluation of peritoneal fluid are of questionable validity for foals. Diagnostically, the most important observation was that maximum peritoneal fluid nucleated cell counts in healthy foals were much lower than reported maximal reference values for adult horses (1.5 x 10(9)/litre versus 5.0 x 10(9)/litre or 10.0 x 10(9)/litre).     

Extreme neutrophilic leucocytosis and intrathoracic mass in a Fox Terrier

Extract

An 8-year-old female Fox Terrier was presented for acute anorexia and depression. A haemogram revealed extreme neutrophilic leucocytosis (136×10⁹/L neutrophils). By Day 4, the neutrophilia was more marked (214×10⁹/L segmented; 23×10⁹/L band). Imaging revealed a cranial mediastinal mass, pleural effusion and small pneumothorax. Needle aspiration of the mass showed cells resembling malignant histiocytes against a background of mature neutrophils. On Day 7, the mass was surgically removed. Histologically, it revealed a malignancy suggestive of histiocytic sarcoma intensely infiltrated with neutrophils. Immunocyto-chemical investigations are pending. Post-operatively, the dog's appetite and demeanour improved but breathing was laboured, and neutrophilia persisted (300×10⁹/L on Day 14). The dog was humanely killed on Day 14; post mortem examination revealed no distant metastases. This dog's illness is strongly reminiscent of a rare human condition, inflammatory malignant fibrous his-tiocytoma with leukaemoid reaction (IMFH-LR). In IMFH-LR, neoplastic cells produce cytokines that attract neutrophils to the tumour. Other cytokines stimulate the bone marrow to produce extreme neutrophilia. Although paraneoplastic neutrophilia has previously been described in dogs, this is an extreme example and the condition has not previously been associated with histiocytic or intrathoracic malignancies.     

Enzyme activities, protein content and cellular variables in the pulmonary epithelial lining fluid in selected healthy pigs

Reference values of cellular and non-cellular components in the bronchoalveolar lavage fluid (BALF) were established from the BALF specimens obtained from 52 healthy pigs. Using urea as an endogenous marker of dilution, the reference values in the epithelial lining fluid (ELF) were calculated: total cell count 2.71 x 10(9) - 56.49 x 10(9) litre(-1) ELF, alveolar macrophages 2.02 x 10(9) - 49.91 x 10(9) litre(-1) ELF, lymphocytes 0.10 x 10(9) - 4.74 x 10(9) litre(-1) ELF, polymorphonuclear neutrophils 0.01 x 10(9) - 3.48 x 10(9) litre(-1) ELF, protein 0.10 - 13.13 g litre(-1) ELF, lactate dehydrogenase 127-1843 Units litre(-1) ELF, and alkaline phosphatase 86-994 Units litre(-1) ELF. The problems of quantification of BALF components are discussed and a standardized lavage protocol in swine is described, which is essential for the interpretation of diagnostic findings and for the comparison of different BALF specimens.     

Chronic Idiopathic Neutropenia in a Cat

Persistent neutropenia (0-0.6 X 10(9) neutrophils/l) was documented during a 10-month period in a 4-year-old spayed female domestic shorthair cat that was presented for anorexia and depression. Salient abnormalities detected on physical examination were fever (40.3 degrees C), dehydration, and gingivitis. The cat was neutropenic (0.5 X 10(9) neutrophils/l) and enzyme-linked immunosorbent assay (ELISA) test for feline leukemia virus was negative. A bone marrow aspirate showed decreased numbers of mature granulocytic cells. In vitro bone marrow cultures for colony-forming units-granulocyte/macrophage (CFU-GM) were performed comparing bone marrow from the patient with that of a normal cat. The patient had fewer CFU-GM than the control. The number of CFU-GM increased when bone marrow mononuclear cells were cultured in the presence of 10(-5) and 10(-6) mol/l of hydrocortisone, but the cat did not respond to oral prednisolone therapy. The pathogenesis of the neutropenia in this cat remains obscure, but resembles the chronic idiopathic neutropenia syndrome of man.     

Transitional cell carcinoma of the urinary bladder in a 12‐year‐old Belgian Warmblood gelding

A 12‐year‐old Belgian Warmblood gelding was examined for haematuria and dysuria of 24 h duration. Cystoscopy revealed an intraluminal multinodular soft tissue mass originating from the dorsal bladder neck. Histopathological examination of biopsies identified transitional cell carcinoma. The bladder mass was surgically debulked via a temporary perineal urethrotomy. The horse commenced treatment with oral piroxicam. Follow‐up examination 18 months post operatively revealed no evidence of tumour recurrence. Neoplasia of the equine bladder is uncommon and this case describes the successful short‐term outcome of treatment of a transitional cell carcinoma by surgical debulking and oral piroxicam.     

Cytologic diagnosis of generalized cutaneous sporotrichosis in a hunting hound

A 1-year-old male Foxhound/Walker Hound mix was presented to the small animal internal medicine service at Louisiana State University School of Veterinary Medicine with a 6-week history of progressive, multifocal, ulcerative and draining, well-circumscribed lesions in a generalized distribution. Prior to referral, a presumptive diagnosis was made of sterile pyogranulomatous disease; immunosuppressive therapy was instituted but resulted in clinical deterioration. At presentation, the dog had marked neutropenia (1100 neutrophils/microL), and a mild toxic left shift (400 bands/microL). Cytologic findings in the exudates from a draining skin lesion included high numbers of markedly degenerate neutrophils (about 95% of nucleated cells) as well as low numbers of macrophages, small mature lymphocytes, and eosinophils. Low numbers of intracellular (within neutrophils and macrophages) and extracellular, pleomorphic, cigar-to-ovoid shaped organisms ( approximately 3x9 microm) consistent with Sporothrix were observed. Histopathologic examination of a skin biopsy showed marked, chronic, active, ulcerative, pyogranulomatous dermatitis and panniculitis, with intralesional yeast consistent with Sporothrix sp. The etiologic agent was confirmed as Sporothrix schenckii by macerated tissue fungal culture. The patient was treated with itraconazole, enrofloxacin, and clindamycin, with clinical resolution occurring over a 3-month period. This case is a rare example of the cytologic diagnosis of Sporothrix schenckii in a canine patient. Diagnosis of canine sporotrichosis is often challenging and usually requires tissue culture, as infected dogs typically harbor very few organisms. The patient's prior immunosuppressive therapy likely contributed to higher numbers of organisms in exudates from the cutaneous lesions, facilitating cytologic diagnosis.     

Internal abdominal abscesses in the horse: a study of 25 cases

internal abdominal abscesses in 25 horses, including 8 horses that died or were euthanatized, were found to be caused by Streptococcus equi, Streptococcus zooepidemicus, or Corynebacterium pseudotuberculosis. Breed or sex predilection was not found. Although horses of all ages were affected, those under 5 years of age were more commonly affected. Nearly all of the horses had a history of respiratory catarrh or lymphadenitis. Horses with internal abdominal abscesses also had intermittent, prolonged colic or chronic weight loss. Most horses had increased rectal temperature, increased heart and respiratory rates, and varying degrees of anorexia. Chronic depression anemia, increased plasma fibrinogen concentration, increased total plasma protein with hypergammaglobulinemia, and hypoalbuminemia were prominent clinicopathologic findings. Results of rectal examination or surgical exploration often revealed an abdominal mass. Peritoneal fluid from 14 horses was examined, and the protein content was greater than 2.5 g/dl, with increased numbers of neutrophils. Culture results were negative in all 14 cases, although bacteria were seen intracellularly in 5 cases. Long-term (2- to 6-month) antimicrobial therapy with procaine penicillin G resulted in clinical resolution in most of these animals.     

Neurological,imaging and pathological features of a meningeal inflammatory pseudotumour in a Maltese terrier

A five-year eight-month-old Maltese terrier was presented with a 3-week history of progressive paraparesis and pelvic limb ataxia. Neurological examination was consistent with a lesion involving the T3-L3 spinal cord segments. Myelogram and magnetic resonance imaging revealed a spherical, intradural-extramedullary mass lesion at T13/L1. A dorsal laminectomy, durotomy and debulking of the mass were performed. Histopathologic examination revealed a highly cellular tissue, most likely of mesenchymal origin, infiltrated by many lymphocytes, macrophages and neutrophils. The pathological diagnosis of an inflammatory pseudotumour was made. Postsurgical analgesia was achieved with opioids and 2 mg/kg carprofen twice daily for 5 days. When the histopathological diagnosis was made, a tapering course of 1 mg/kg prednisolone twice daily was prescribed, with dose reduction by approximately 50% every 4 to 6 weeks over a 4-month period. Magnetic resonance imaging was repeated at 22, 32 and 85 weeks postsurgery; no signs of regrowth could be detected and the patient recovered with residual mild paraparesis. Inflammatory pseudotumour has not been documented previously at this site in dogs and, although rare, should be considered in the differential diagnosis of a focal mass lesion affecting the spinal cord. Surgical debulking and immunomodulatory therapy can be curative.     

Acquired amegakaryocytic thrombocytopenia--four cases and a literature review

Acquired amegakaryocytic thrombocytopenla was diagnosed in four dogs. Initial platelet counts in all four dogs were less than 50,000 x 10(9)/litre and initial bone marrow examinations revealed megakaryocytic hypoplasia with minimal changes in the erythroid and myeloid cell lines. Two dogs had evidence of idiopathic immune-mediated disease and two dogs had evidence of associated infectious disease. One dog had a positive antibody titre to Borrella burgdorferi, and one dog had positive titres to both Ehrlichia canis and B. burgdorferi. Treatment consisted of prednisone and cyclophosphamide for the dogs with presumptive immune-mediated disease, and prednisone and tetracycline for the dogs with positive antibody titres to the Infectious organisms. Both dogs with evidence of associated infectious disease responded to treatment. A postmortem examination did not reveal the underlying aetiology in the two dogs with presumptive idiopathic immune-mediated disease.     

Oil Red O-positive lipid in peritoneal fluid from a horse with a rectal tear

A 4-year-old Quarter Horse mare was presented to the Texas A&M University Veterinary Medical Teaching Hospital for evaluation of a rectal tear. On initial evaluation, rectal palpation and colonoscopy revealed a grade IIIb rectal tear. Analysis of peritoneal fluid revealed a modified transudate. Preliminary supportive care included fluid therapy and mineral oil administration via nasogastric tube. Approximately 48 hours after presentation, a second abdominocentesis was performed, and cytologic examination of the fluid revealed a marked suppurative exudate. Round clear nonrefractile material observed within neutrophils and macrophages and in the background stained bright pink to red with Oil Red O, confirming the material as lipid, likely from leakage of mineral oil through the rectal tear. The condition of the mare deteriorated and euthanasia was elected due to the poor prognosis. At necropsy, gross and histologic findings included peritoneal effusion and a full-thickness rectal tear with transmural necrotizing pyogranulomatous colitis and fibrinous peritonitis. To the authors' knowledge, this is the first reported case of Oil Red O-positive lipid vacuoles in the peritoneal fluid of a horse from presumed leakage of mineral oil through a transmural rectal perforation. The frequency of this occurrence in horses is unknown, but it is important for cytopathologists to be familiar with the appearance and significance of lipid-type droplets in phagocytic cells in cytologic fluid analysis specimens.     

Treatment and therapeutic monitoring of canine hypothyroidism

Thirty-one dogs with spontaneous hypothyroidism were treated with thyroid hormone replacement therapy (THRT) and monitored for approximately three months. Good clinical and laboratory control was ultimately achieved in all cases with a mean L-thyroxine (T4) dose of 0.026 mg/kg administered once daily. There was a significant increase and decrease in circulating total T4 and canine thyroid stimulating hormone (cTSH) concentrations, respectively, after starting THRT. After commencing treatment, 11 cases subsequently required an increase and three cases required a decrease in dose to achieve optimal clinical control. Median (semi interquartile range [SIR]) circulating six-hour post-pill total T4 (53.6 [27.91 nmol/litre) and cTSH (0.03 [0] microg/litre) concentrations were significantly increased and decreased, respectively, in treated dogs that did not require a dose change; corresponding values in treated dogs in which an increase in dose was required were 29.3 (12.7) nmol/litre and 0.15 (0.62) microg/litre, respectively. However, circulating cTSH measurement was of limited value in assessing therapeutic control because, although increased values were associated with inadequate therapy, reference range cTSH values were common in inadequately treated dogs. Lethargy and mental demeanour were typically the first clinical signs to improve, with significant bodyweight reduction occurring within two weeks of commencing THRT. Routine clinicopathological monitoring was of value in confirming a general metabolic response to THRT, but was of limited value in accurately monitoring cases or tailoring therapy in individual cases.     

Colonic adenocarcinoma with osseous metaplasia in a horse

Rectal palpation of a 30-year-old mixed-breed mare with chronic weight loss and intermittent, refractory abdominal pain revealed a mass in the right caudoventral portion of the abdomen. Hematologic and serum biochemical findings were normal except for slight mature neutrophilia and mildly high alkaline phosphatase activity and total bilirubin concentration. Cytologic examination of a specimen obtained by abdominocentesis revealed equal numbers of nondegenerative neutrophils and macrophages, but no evidence of neoplastic cells. The mare continued to have signs of abdominal discomfort and was euthanatized. Necropsy revealed a large mass at the junction of the right dorsal colon and transverse colon, and several smaller masses in the liver. Histologic characteristics of the small-colon mass were consistent with colonic adenocarcinoma with osseous metaplasia.     

Septic arthritis in 15 standardbred racehorses after intra-articular injection.

Case histories, results of synovial fluid analyses, treatment regimens and outcome are described for 15 adult Standardbred horses with confirmed post-injection septic arthritis. Joint sepsis followed injection of corticosteroids, hyaluronic acid, polysulphated glycosaminoglycan, or local anaesthetic. The median interval from injection to appearance of clinical signs was 2.5 days, and median interval from injection to referral was 9 days. The median initial synovial leucocyte count on admission was 57 x 10(9)/litre, but there was a wide range of values (18-258 x 10(9)/litre). The median synovial neutrophil percentage was 95% (77-99%). All bacterial isolates were Gram-positive cocci, 86% of which were staphylococci. All treated horses (12/15) initially received broad-spectrum parenteral antibiotic therapy, and the articulations of all horses except one were lavaged, either with non-surgical through-and-through techniques only (N = 3), or surgically with arthrotomy (N = 1) or arthroscopy (N = 7). The owners of all treated horses were contacted and racing records were consulted. Eleven of 12 horses returned to racing. Outcome was judged as either satisfactory (3/12) if the horse had returned to racing levels similar to or better than before treatment, or unsatisfactory (9/12) if the horse had poorer performance or could not return to racing. The 3 horses with satisfactory follow-up had been treated with arthroscopy and post-surgical closed suction drainage. The results of bacterial cultures suggest that the initial antimicrobial agents used should be effective against penicillin-resistant staphylococci.     

Stereotactic radiation treatment of a pituitary mass in a rabbit

A 9-year-old female spayed Holland Lop rabbit (Oryctolagus cuniculus) presented with abnormal eyelid positioning on the right eye of 2 week duration. A full neurological examination revealed ptosis, enopthalmia, decreased palpebral reflex of the right eye. A pre and post contrast CT-study confirmed a large heterogeneously contrast-enhancing and partially peripherally mineralized parasellar pituitary mass. Stereotactic radiation was performed delivering 3 fractions of 8 Gy every other day (total dose 24 Gy) using volumetric-modulated arc therapy for the pituitary mass. A progressive decrease in size of the pituitary mass was observed on two follow-up CT-studies at six- and eighteen-months post-radiotherapy. The adrenal panels performed during follow-up visits suggested increased adrenal activity post-radiotherapy. No adverse effects of radiation therapy were noted at home or subsequent veterinary visits. CT imaging was a reliable modality for diagnosing and monitoringthe pituitary mass. Treatment with stereotactic radiotherapy resulted in a marked reduction in the pituitary mass volume with a long survival time and without adverse effects. Radiation therapy should be considered a treatment option in rabbits with pituitary tumors and the protocol used in this case could be used as a reference for future cases.     

Hepatocellular carcinoma with secondary abscessation in a cat

A 16-year-old castrated male domestic shorthair cat was presented for investigation of weight loss, lethargy, inappetence and polydypsia. On serum biochemical analysis there was evidence of severe hepatocellular damage and cholestasis. Abdominal ultrasonographic examination revealed an irregular lesion of mixed echogenicity in a left hepatic lobe. It was compromised of a hypoechoic periphery surrounding an anechoic central area containing highly echogenic densities with distal acoustic shadowing suggestive of gas formation. On necropsy, the only gross abnormality was a solitary 5 cm x 3 cm x 3 cm multilobulated mass in the left lateral hepatic lobe, containing foul-smelling purulent fluid within a thick fibrous wall. Cytological examination of the fluid revealed numerous degenerate neutrophils and large numbers of Gram-positive spore-forming rods. The histopathological diagnosis was hepatocellular carcinoma with secondary abscessation. The bacterial morphology was consistent with Clostridia sp. Both hepatocellular carcinoma and focal hepatic abscessation are rare in cats. Hepatic abscesses should be included in the differential diagnosis of cats with non-specific signs, even in the absence of biochemical evidence of a hepatopathy.     

Tertiary hypothyroidism in a dog

: A nine-year-old male entire Labrador was diagnosed with pituitary dependent hyperadrenocorticism. Following seven months of successful mitotane therapy, the dog presented with marked weight gain, seborrhoea and alopecia. Routine clinicopathological analyses revealed marked hypercholesterolaemia. Serum total and free thyroxine (T4) concentrations were below their respective reference ranges. Serum thyroid stimulating hormone (cTSH) concentration was within reference range. TSH and thyrotropin releasing hormone (TRH) response tests revealed adequate stimulation of total T4 in both, and cTSH in the latter test. Magnetic resonance imaging revealed a mass arising from the pituitary fossa, with suprasellar extension. A diagnosis of tertiary hypothyroidism was made. Following four weeks of levothyroxine therapy, circulating cholesterol concentration had declined, weight loss had ensued and dermatological abnormalities had improved. Euthanasia was performed four months later due to the development of neurological signs. A highly infiltrative pituitary adenoma, with effacement of the overlying hypothalamus was identified on post mortem examination. Tertiary hypothyroidism has not been previously reported in dogs.     

CSF from a puppy with a cerebral vascular hamartoma

A 9-week-old puppy with refractory seizures and a dome-shaped head presented to the Mississippi State College of Veterinary Medicine Specialty Center for suspected hydrocephalus. Computerized tomography (CT) findings included transtentorial herniation and an intra-axial mass with dystrophic mineralization. Cerebrospinal fluid analysis revealed an increased nucleated cell count of 1100/μl (RI < 5/μl), erythrocyte count of 2.2 × 10⁶/μl, and markedly increased microprotein of 1939 mg/dl (RI < 30 mg/dl). On cytologic examination of the CSF, numerous erythrophagocytic, and hemosiderin-laden macrophages were observed, which indicated chronic active hemorrhage. Many neutrophils, macrophages, and lymphocytes that contained numerous intracytoplasmic, pleomorphic, bright yellow crystals were observed. Considering the ongoing hemorrhage, the crystals were presumed to be hematoidin. A biopsy with histopathology was performed on the intra-axial mass, and the results were consistent with a vascular hamartoma. We speculate that the formation of these crystals was related to the ongoing hemorrhage associated with the vascular hamartoma. Identification of these crystals may be useful to aid in the identification of chronic hemorrhage associated with vascular malformations or lesions within the central nervous system.     

Piroxicam Therapy in 34 Dogs With Transitional Cell Carcinoma of the Urinary Bladder

Thirty-four dogs with histopathologically confirmed, measurable, nonresectable transitional cell carcinoma of the urinary bladder were treated with piroxicam (0.3 mg/kg PO sid) and were evaluated for tumor response and drug toxicity. Dogs were evaluated at the Purdue University Veterinary Teaching Hospital by means of physical examination, thoracic and abdominal radiography, cystography, complete blood count, serum biochemistry profile, and urinalysis. In selected cases, prostaglandin E₂ (PGE₂) concentrations in plasma and in supernatants of stimulated monocytes, and natural killer cell activity were quantified, Dogs were evaluated before therapy and at 28 and 56 days after initiation of therapy. Dogs with stable disease or remission at 56 days remained on the study and were evaluated at 1 to 2 month intervals. Tumor responses were 2 complete remissions, 4 partial remissions, 18 stable diseases. and 10 progressive diseases. The median survival of all dogs was 181 days (range, 28 to 720+ days), with 2 dogs still alive. Piroxicam toxicity consisted of gastrointestinal irritation in 6 dogs and renal papillary necrosis (detected at necropsy) in 2 dogs. Monocyte production of PGE₂ appeared to decrease with therapy in dogs whose tumors were decreasing in size, and increased in dogs with tumor progression. A consistent pattern in natural killer cell activity was not observed. In vitro cytotoxicity assays against 4 canine tumor cell lines revealed no direct antitumor effects of piroxicam. In summary, antitumor activity, which was not likely the result of a direct cytotoxic effect, was observed in dogs with transitional cell carcinoma of the bladder treated with piroxicam.     

Salmonella Brandenburg — emergence of a variant strain on a sheep farm in the South Island of New Zealand

AIM: To compare the rectal and I/V administration of tramadol in dogs, to assess both its pharmacokinetic properties and absolute bioavailability.

METHODS: After rectal administration via suppositories and I/V injection of tramadol (4 mg/kg), the concentration of tramadol and its main metabolites, O-desmethyl-tramadol (M1), N-desmethyl-tramadol (M2) and N,O-didesmethyl-tramadol (M5), were determined in plasma, using high-performance liquid chromatography (HPLC). A balanced cross-over study was used, involving six male Beagle dogs.

RESULTS: Plasma concentrations after rectal and I/V administration were fitted on the basis of mono- and bi-compartmental models, respectively. Following rectal administration tramadol was detected from 5 minutes up to 10 hours, in lesser amounts than M5 and M2, while M1 was detected in negligible amounts. Following I/V administration tramadol was detected up to 10 hours, M2 and M5 were detected at similar concentrations, and M1 was present at low concentrations. The area under the curve (AUC) of the three metabolites did not differ significantly after either route of administration of tramadol. The absolute bioavailability of tramadol via rectal administration was 10 (SD 4)%.

CONCLUSIONS: After rectal administration of tramadol suppositories, absorption of the active ingredient was rapid, but its metabolism quickly transformed the parent drug to high levels of M2 and M5.

CLINICAL RELEVANCE: In the dog, rectal pharmaceutical formulation of tramadol would have a different pharmacokinetic behaviour than in humans.