Light microscopic observations of the ruminal papillae of cattle on diets with divergent forage to cereal ratios.

High levels of supplementation with cereal increases production rates in cattle but can increase incidence of disease, ranging from mild indigestion to acute ruminal acidosis and death. Therefore, there is motivation to determine biological markers which can be used to identify whether animals have been, or are being fed, sufficient or excessive cereals. This study aimed to describe light microscopic findings from animals being fed diverse dietary cereal proportions and to test the performance of a novel rumen epithelial scoring system. Rumen wall tissue samples were obtained from the abattoir from 195 cattle from 11 Scottish farms and processed for histological examination. Light microscopic examination was used to characterise ruminal epithelial response to dietary challenge. Secondary objectives included describing the distribution of immune-related cells in bovine ruminal epithelium and assessing the use of a modified Elastin Martius Scarlet Blue stain (EMSB) for histological examination of the rumen epithelium. Cells staining positive for cluster of differentiation 3 were distributed mainly in the lower layers of the stratum basale and were found in higher densities in animals offered lower cereal proportion diets. Cells staining positive for major histocompatibility complex class 2 (MHCII) were most common in perivascular locations and in the junction between the lower stratum basale and the propria-submucosa. The density of MHCII positive staining cells was higher in animals on lower cereal diets. The level of supplementation with cereal was also associated with the thickness of the stratum corneum (SCT) and stratum granulosum (SGT), the integrity of the stratum corneum and sloughing of cornified cells. There were no advantages in using EMSB stain over haematoxylin and eosin (H&E) in this scoring system. We concluded that a scoring system that included only SCT, SGT and a measure of the loss of appearance of intercellular space allowed differentiation of groups of animals according to the level of cereal supplementation.

Pericardial myxoid liposarcoma in a common eland (Taurotragus oryx).

A pericardial myxoid liposarcoma was diagnosed in a common eland (Taurotragus oryx) based on gross, microscopical and immunohistochemical findings. The pericardial and epicardial tissues were soft and uniformly thickened. Microscopically, the neoplastic mass consisted of stellate cells embedded in a myxoid matrix. These cells contained cytoplasmic vacuoles stained by oil red O. Immunohistochemical analysis showed the neoplastic cells to express vimentin and S-100.

Prevalence and breed distribution of chronic pancreatitis at post-mortem examination in first-opinion dogs.

OBJECTIVES: To assess the prevalence of canine chronic pancreatitis in first-opinion practice and identify breed associations or other risk factors. METHODS: Three sections of pancreas were taken from 200 unselected canine post-mortem examinations from first-opinion practices. Sections were graded for inflammation, fibrosis and other lesions. Prevalence and relative risks of chronic pancreatitis and other pancreatic diseases were calculated. RESULTS: The prevalence of chronic pancreatitis was 34 per cent omitting the autolysed cases. Cavalier King Charles spaniels, collies and boxers had increased relative risks of chronic pancreatitis; cocker spaniels had an increased relative risks of acute and chronic pancreatitis combined. Fifty-seven per cent of cases of chronic pancreatitis were classified histologically as moderate or marked. Forty-one per cent of cases involved all three sections. Dogs with chronic pancreatitis were more commonly female and overweight, but neither factor increased the relative risk of chronic pancreatitis. There were breed differences in histological appearances and 24.5 per cent of cases were too autolysed to interpret with an increased relative risk of autolysis in a number of large breeds. CLINICAL SIGNIFICANCE: Chronic pancreatitis is a common, under-estimated disease in the first-opinion dog population with distinctive breed risks and histological appearances.

Osteodystrophia fibrosa in two guinea pigs.

Two adult guinea pigs were examined because they were lethargic and reluctant to walk. Additionally, I guinea pig had otitis media, and the other had dental malocclusion. Both guinea pigs had been fed a commercially available diet of cereals and pellets enriched with vitamin C and formulated for this species. Radiographically, the guinea pigs had coarse trabecular bone patterns, skeletal deformations, pathologic fractures, and polyarthritic degenerative joint disease. A double cortical line was also evident on several long bones, the pelvis, and the vertebrae. A diagnosis of osteopenia was confirmed by use of dual-energy x-ray absorptiometry. Analysis of a food sample fed to 1 guinea pig revealed calcium and phosphorus contents of 0.524 and 0.425%, respectively (Ca:P ratio, 1.23:1). Microscopic examination of bone tissue from both guinea pigs revealed severe fibrous osteodystrophy. Nutritional secondary hyperparathyroidism caused by calcium-phosphorus imbalance was considered to be the underlying cause of osteodystrophia fibrosa in both guinea pigs.

Serum alpha-tocopherol concentrations in German shepherd dogs with chronic degenerative radiculomyelopathy.

The concentration of serum alpha-tocopherol was measured in German shepherd dogs with chronic degenerative radiculomyopathy, and in German shepherd dogs and dogs of other breeds unaffected by the condition. The mean concentration was significantly higher in German shepherd dogs with the condition than in other breeds of dog unaffected by it, but it was not significantly higher than in unaffected German shepherd dogs. Estimates of components of variance indicated that the concentration varied more widely in individual affected dogs than in unaffected dogs, irrespective of breed. These results suggest that chronic degenerative radiculomyopathy in German shepherd dogs is unlikely to be due to uncomplicated vitamin E deficiency.

Primary T-cell lymphoma of the central nervous system in a dog.

Primary T-cell lymphoma is a rare form of CNS neoplasia. Diagnosis may be aided by use of cytologic examination of CSF. Primary CNS T-cell lymphoma should be considered in a patient with multiple cranial nerve abnormalities, even if results of imaging studies are considered normal.

Central nervous system pathology in 25 dogs with chronic degenerative radiculomyelopathy.

The neuropathology of 20 German shepherd dogs and five German shepherd dog crosses with chronic degenerative radiculomyelopathy were analysed by conventional techniques, immunocytochemistry and electron microscopy. There were previously unrecognised changes in brain nuclei. In the spinal cord, both motor and sensory tracts were involved, principally in their more distal regions. Wallerian degeneration affected the corticorubrospinal pathways in the lateral columns and the ventral funiculi, predominantly in the caudal thoracic and lumbar segments, although more cranial involvement was also observed. The dorsal columns were affected in the caudal lumbar region and the cervical fasciculus gracilis. The regional distribution was variable between cases. Within the brain, abnormalities, including chromatolysis, gliosis and neuronal loss were observed in the red nucleus, lateral vestibular nucleus and, occasionally, in the dentate nucleus. The changes in brain nuclei were compared with those found in dogs at various times after a focal spinal injury. The neuronal changes in the brain may be related to the primary site of damage, and possible aetiological mechanisms are discussed.

Bromfenac (Duract)-associated hepatic failure requiring liver transplantation.

Bromfenac sodium (Duract) is a phenylacetic acid-derived nonsteroidal anti-inflammatory agent introduced in the United States in 1997 and withdrawn in 1998. We describe the first case of fulminant hepatic failure associated with this agent treated successfully with liver transplantation. Similarities to hepatotoxicity with related agents is discussed.

Focused microbiologic surveillance by specific hospital unit: practical application and clinical utility.

Focused microbiologic surveillance by specific hospital intensive care units (ICUs) revealed important differences in the occurrence of pathogens among units and at different times. Moreover, there were striking differences between the antibiogram summaries from certain ICUs and those from the hospital as a whole. Accordingly, an ongoing focused microbiologic surveillance was conducted for hospital ICUs to define unit-specific problems more clearly. To apply these data practically, results of focused surveillance were given to the ICU medical directors. The directors were able to institute unit-specific modifications of antimicrobial usage based upon the prevalent pathogens and their susceptibility patterns within each unit. After 1 year of this approach, the susceptibility patterns of Pseudomonas aeruginosa to imipenem and other antipseudomonal beta-lactam agents were improved in a number of ICUs that had previously noted resistance problems of several years' duration. Susceptibility of P aeruginosa was markedly improved in the medical ICU. The susceptibility patterns of Enterobacter cloacae were less affected, if at all. A review of antimicrobial use revealed that the use of most antipseudomonal agents in the medical ICU had decreased by approximately 50% or more. It is concluded that modification of antimicrobial use in ICUs based on focused microbiologic surveillance is a promising way to detect and minimize problems with resistance.

Focused microbiologic surveillance by specific hospital unit as a sensitive means of defining antimicrobial resistance problems.

An annual summary of susceptibility patterns for the predominant clinical isolates from hospitalized patients can be of considerable assistance in selecting antimicrobial agents for sepsis of unclear etiology, as well as for guiding empiric therapy for other serious infections. Yearly summaries of the susceptibility patterns of the predominant clinical isolates from all patients hospitalized at Vanderbilt University Hospital (VUH) from July 1987 through June 1991 revealed only minor differences over time in susceptibility patterns. However, the clinical impression of physicians treating patients in various intensive care units (ICUs) was that there were serious resistance problems in some units. To better define the prevalence of clinical isolates and their susceptibility patterns for patients within ICUs at VUH, we utilized a "focused microbiologic surveillance" technique that addressed each unit separately. Both the predominant clinical isolates and their susceptibility patterns were determined and compared with those from the hospital as a whole. Because susceptibility patterns of clinical isolates by site of infection within these units were considered important, we also reviewed the summaries of susceptibility patterns for blood, sputum, and urine isolates from patients in ICUs and compared these with the summaries from each ICU and from the hospital. No major resistance problems were identified on a hospital-wide basis. In contrast, focused microbiologic surveillance by specific hospital ICU revealed important differences in the prevalence of pathogens among units and at different times. In 1987, Pseudomonas aeruginosa was the single most common Gram-negative organism isolated in the neonatal unit, while Acinetobacter spp. were rarely isolated. By 1991, this trend was completely reversed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adverse drug reaction surveillance and risk management.

ADR programs are most successful when developed from a multidisciplinary approach. Physicians and other health care workers should be encouraged to report and evaluate ADRs to potentially decrease risks involved in an ADR case. Management of ADRs should include prompt feedback of individual patient and grouped data for educational and risk management purposes. Risk managers should play a significant role in all aspects of an ADR surveillance program.

Use of a database computer program to identify trends in reporting of adverse drug reactions.

A computerized system for concurrent monitoring and reporting of adverse drug reactions (ADRs) in a university hospital is described. The program, which began in 1988, was developed in collaboration with the hospital's pharmacy and therapeutics committee and quality assurance committee. Quality assurance nurses review patients' charts every three days during hospitalization; if an ADR is detected, the nurse completes an ADR report form. A computer database is used to sort and store 15 data elements taken from each ADR form. Individual pharmacists and hospital review committees evaluate the recorded ADRs. The database can present the data for analysis by different variables such as patient age, clinical service, and implicated drugs. Retrieval of such data permits easier evaluation of trends in ADR reports and identification of reactions that should be reported to FDA. Educational programs for staff members can be targeted to address problems occurring within the institution. During the first nine months of the program 340 ADRs were reported; 15 reports were submitted to FDA, and serious problems were reviewed at medical grand rounds. A bimonthly newsletter that reviews recently reported ADRs was begun. The monitoring program has facilitated rapid detection and evaluation of ADRs.