26 research outputs found
Twenty two cases of canine neural angiostronglyosis in eastern Australia (2002-2005) and a review of the literature
Cases of canine neural angiostrongylosis (NA) with cerebrospinal fluid (CSF) evaluations in the peer-reviewed literature were tabulated. All cases were from Australia. A retrospective cohort of 59 dogs was contrasted with a series of 22 new cases where NA was diagnosed by the presence of both eosinophilic pleocytosis and anti-Angiostrongylus cantonensis immunloglobulins (IgG) in CSF, determined by ELISA or Western blot. Both cohorts were drawn from south east Queensland and Sydney. The retrospective cohort comprised mostly pups presented for hind limb weakness with hyperaesthesia, a mixture of upper motor neurone (UMN) and lower motor neurone (LMN) signs in the hind limbs and urinary incontinence. Signs were attributed to larval migration through peripheral nerves, nerve roots, spinal cord and brain associated with an ascending eosinophilic meningo-encephomyelitis. The contemporary cohort consisted of a mixture of pups, young adult and mature dogs, with a wider range of signs including (i) paraparesis/proprioceptive ataxia (ii) lumbar and tail base hyperaesthesia, (iii) multi-focal central nervous system dysfunction, or (iv) focal disease with neck pain, cranial neuropathy and altered mentation. Cases were seen throughout the year, most between April and July (inclusive). There was a preponderance of large breeds. Often littermates, or multiple animals from the same kennel, were affected simultaneously or sequentially. A presumptive diagnosis was based on consistent signs, proximity to rats, ingestion/chewing of slugs or snails and eosinophilic pleocytosis. NA was diagnosed by demonstrating anti-A. cantonensis IgG in CSF. Detecting anti-A. cantonensis IgG in serum was unhelpful because many normal dogs (20/21 lb dogs; 8/22 of a hospital population) had such antibodies, often at substantial titres. Most NA cases in the contemporary series (19/22) and many pups (16/38) in the retrospective cohort were managed successfully using high doses of prednisolone and opioids. Treatment often included antibiotics administered in case protozoan encephalomyelitis or translocated bacterial meningitis was present. Supportive measures included bladder care and physiotherapy. Several dogs were left with permanent neural deficits. Dogs are an important sentinel species for NA. Human cases and numerous cases in tawny frogmouths were reported from the same regions as affected dogs over the study period
Progression of anemia and its relationship with renal function, blood pressure, and erythropoietin in rats with chronic kidney disease
Background: In chronic kidney disease (CKD), anemia and hypertension are significant co-morbidities that contribute to cardiovascular and renal disease progression. Objective: The purpose of the study was to identify correlations between changes in hematologic variables against markers of renal function, blood pressure, and erythropoietin (EPO) in a naturally occurring hypertensive model of CKD, the Lewis polycystic kidney (LPK) rat. Methods: Complete blood count, systolic blood pressure, urea and creatinine concentration, urinary protein to creatinine ratio, and plasma EPO concentration were determined in control Lewis (n = 51) and LPK rats (n = 56) aged 6-24 weeks. Renal EPO gene expression and RBC osmotic fragility were also documented. Hematopoiesis in spleen and bone marrow were assessed. Results: Lewis polycystic kidney rats had increasing urea and creatinine concentrations, concurrent with the development of a nonregenerative normocytic/normochromic anemia and hypertension, with a significant negative correlation between both HGB and HCT with urea concentration and blood pressure (P < .01). HCT was also significantly negatively correlated with creatinine concentration (P = .014). WBC was significantly negatively correlated with urea (P < .01). Plasma EPO concentration was increased and renal EPO mRNA expression was significantly upregulated in LPK animals. The former was significantly positively correlated with blood pressure and platelet count (P < .05). RBC osmotic fragility was normal in LPK rats and there was no evidence for increased RBC elimination or extramedullary hematopoiesis. Conclusions: Marked anemia in the LPK CKD rodent model in the presence of elevated EPO suggests inefficient erythropoiesis that is correlated with plasma urea concentration and blood pressure.13 page(s
Assessments of feline plasma biochemistry reference intervals for three in-house analysers and a commercial laboratory analyser.
For each species, the manufacturers of in-house analysers (and commercial laboratories) provide standard reference intervals (RIs) that do not account for any differences such as geographical population differences and do not overtly state the potential for variation between results obtained from serum or plasma. Additionally, biases have been demonstrated for in-house analysers which result in different RIs for each different type of analyser. The objective of this study was to calculate RIs (with 90% confidence intervals [CIs]) for 13 biochemistry analytes when tested on three commonly used in-house veterinary analysers, as well as a commercial laboratory analyser. The calculated RIs were then compared with those provided by the in-house analyser manufacturers and the commercial laboratory. Plasma samples were collected from 53 clinically normal cats. After centrifugation, plasma was divided into four aliquots; one aliquot was sent to the commercial laboratory and the remaining three were tested using the in-house biochemistry analysers. The distribution of results was used to choose the appropriate statistical technique for each analyte from each analyser to calculate RIs. Provided reference limits were deemed appropriate if they fell within the 90% CIs of the calculated reference limits. Transference validation was performed on provided and calculated RIs. Twenty-nine of a possible 102 provided reference limits (28%) were within the calculated 90% CIs. To ensure proper interpretation of laboratory results, practitioners should determine RIs for their practice populations and/or use reference change values when assessing their patients’ clinical chemistry results
Comparisons of results between three in-house biochemistry analysers and a commercial laboratory analyser for feline plasma using multiple quality specifications
In-house plasma biochemistry analysis is commonplace in veterinary practice but there are few studies assessing the results from such instruments. Method comparison in human clinical pathology uses results from both precision and bias studies to determine whether results fall within a margin of “acceptable” or “allowable” total error. This study aimed to assess the clinical acceptability of plasma biochemistry results determined by in-house analyzers compared to a commercial laboratory analyzer. Clinical acceptability of analytes from in-house biochemistry analyzers was assessed by determining the percentage of results from feline plasma samples within coverage ranges determined from (a) biological variation, (b) those published by the American Society for Veterinary Clinical Pathology (ASVCP), as well as (c) calculated total error and (d) expanded measurement uncertainty. Calculated total error and expanded measurement uncertainty ranges were calculated from prior quality control material analyses. Between 80 to 87 % of results fell within minimal quality standards determined from biological variation. Approximately 90 % of results fell within “acceptable total error” ranges published by ASVCP. Overall, in-house analyzers provide acceptable results, with few clinical decisions affected by results determined from any of the three in-house analyzers compared to the commercial laboratory results. Keywords: Acceptable total error, Biochemistry analyzer, Biological variation, Clinical chemistry, Diagnostic test evaluation, Method compariso
Bias in feline plasma biochemistry results between three in-house analysers and a commercial laboratory analyser: results should not be directly compared
In-house analysers are commonplace in small animal practices but cannot be calibrated by the operator; therefore, any bias in the generated plasma analyte values cannot be corrected. Guidelines such as grading of renal disease and published reference intervals (RIs) in veterinary textbooks assume plasma biochemistry values generated by different analysers are equivalent. This study evaluated the degree of bias, as well as if bias was constant or proportional, for feline plasma biochemical analytes assessed by three in-house biochemistry analysers compared with a commercial laboratory analyser. Blood samples were collected on 101 occasions from 94 cats and, after centrifugation, plasma was divided into four aliquots. One aliquot was sent to the commercial laboratory and the remaining three were tested using the in-house biochemistry analysers. Results from each analyser were compared with the commercial laboratory results by difference plots and analyses, and by comparing percentages of results within provided RIs. Substantial bias was evident relative to the results of the commercial analyser for at least half of the analytes tested for each machine. In most cases, bias was proportional, meaning that the difference between the methods varied with the concentration of the analyte. The results demonstrate that values obtained from these analysers should not be directly compared and that RIs are not transferable between these analysers. Potential effects of bias on clinical decision-making may be overcome by use of appropriately generated RIs, or reference change values which, for most biochemistry analytes, are more appropriate than subject-based RIs
Needing a drink: Rainfall and temperature drive the use of free water by a threatened arboreal folivore.
Arboreal folivores are particularly vulnerable to the impacts of extreme climate change-driven heatwaves and droughts as they rely on leaf moisture to maintain hydration. During these increasingly frequent and intense weather events, leaf water content may not be enough to meet their moisture requirements, potentially leading to large-scale mortality due to dehydration. Water supplementation could be critical for the conservation of these animals. We tested artificial water stations for a threatened arboreal folivore, the koala (Phascolarctos cinereus), as a potential mitigation measure during hot and dry weather in New South Wales, Australia. We provided ground and tree drinkers to koalas and investigated changes in use with season, environmental conditions and foliar moisture. Our study provides first evidence of the regular use of free water by koalas. Koalas used supplemented water extensively throughout the year, even during cooler months. Time spent drinking varied with season and depended on days since last rain and temperature. The more days without rain, the more time koalas spent drinking. When temperature was high, visits to water stations were more frequent, indicating that in hot weather koalas need regular access to free water. Our results suggest that future changes in rainfall regimes and temperature in Australia have the potential to critically affect koala populations. Our conclusions can be applied to many other arboreal folivorous mammals worldwide which rely on leaves for their nutritional and water requirements. Artificial water stations may facilitate the resilience of vulnerable arboreal folivores during heat and drought events and may help mitigate the effects of climate change
Repeatability of results from three in-house biochemistry analysers and a commercial laboratory analyser used in small animal practice
The repeatability (precision) of clinical pathology results is vital for confidence in the measured values. Comparison to biological variation is an accepted standard for instrument/method performance in human clinical pathology. This study aims to assess precision of biochemistry results from three in-house analyzers and one commercial laboratory analyzer in relation to biological variation and to compare precision between the in-house analyzers and the commercial laboratory analyzer. Two commercially available quality control materials (QCMs) were repeatedly tested on the same and different days. Coefficients of variation were calculated and assessed in relation to published biological variation data for cats and dogs. In-house analyzer results were compared to results from the commercial laboratory. Seven of 13 analytes assessed met desirable quality precision standards for one QCM and minimum quality standards for the other QCM on all analyzers for both cats and dogs. For more than half of all determinations across all in-house analyzers, precision was as good as or better than the commercial laboratory analyzer. The precision of results from the analyzers assessed for most of the analytes tested is generally high, so large differences between repeated results from the same patient are probably due to biological changes rather than analyzer variation. Keywords: Biochemistry analyzer Biological variation Clinical chemistry Diagnostic test evaluation Precision Repeatability Small animal Veterinar
Biological variation and reference change values of feline plasma biochemistry analytes.
This is the first report concerning biological variation and reference change values of feline plasma biochemistry components in the peer-reviewed literature. Biological variation refers to inherent physiological variation of analytes. The ratio of individual biological variation to group biological variation is referred to as an analyte's index of individuality. This index determines the suitability of an analyte to be assessed in relation to population- or subject-based reference intervals. A subject-based reference interval is referred to as a reference change value or critical difference, and is calculated from individual biological variation. Fourteen cats were sampled for plasma biochemistry analysis once weekly for 6 weeks. Samples were stored and then tested at the same time. Results were assessed in duplicate and coefficients of variation for each analyte were isolated to distinguish variation within each subject, between all subjects and by the analyser. From these results, an index of individuality and reference change values were determined for each analyte. Five plasma biochemistry analytes (alkaline phosphatase, alanine aminotransferase, cholesterol, creatinine and globulin) had high individuality and, therefore, subject-based reference intervals are more appropriate; only one analyte (sodium) had low individuality, indicating that population-based reference intervals are appropriate. Most analytes had intermediate individuality so population-based reference intervals should be assessed in relation to subject-based reference intervals. The results of this study demonstrate high individuality for most analytes and, therefore, that population-based reference intervals are of limited utility for most biochemical analytes in cats
Aldosterone and progesterone-secreting adrenocortical adenocarcinoma in a cat with a concurrent meningioma
Case summary A 12-year-old, male neutered domestic shorthair cat was referred for investigation of suspected hyperaldosteronism due to persistent hypokalaemia, hindlimb ataxia, weakness of 1 month’s duration and a left adrenal mass that was detected on abdominal ultrasound. Neurological examination findings at referral were suggestive of a concurrent left forebrain lesion. Hyperaldosteronism and concurrent hyperprogesteronism were confirmed on endocrine testing. On computed tomography (CT) of the abdomen and thorax there was no evidence of local vascular invasion by the adrenal mass or of metastatic disease. CT and magnetic resonance imaging featured a large, focal rim-enhancing extra-axial left forebrain lesion consistent with a meningioma. Surgical excision of the forebrain mass was followed by adrenalectomy 2 weeks later. The tumours were classified on histopathology as a psammomatous meningioma and an adrenocortical adenocarcinoma, respectively. Immunohistochemical staining of the meningioma confirmed the presence of progesterone receptors. The cat remains well 2 years later. Relevance and novel information In humans, elevated serum progesterone levels have been associated with rapid growth of meningiomas due to the presence of progesterone receptors on the tumour. This is the first report of a cat with a progesterone and aldosterone-secreting adrenocortical adenocarcinoma and a concurrent meningioma. Clinicians should be aware of the potential effect of elevated progesterone on meningiomas in cats