Enter your email address above to receive an alert every time a new issue is published.
Lack of associations between ultrasonographic appearance of parenchymal lesions of the canine liver and histological diagnosis.
Warren-Smith, C. M. R., Andrew, S., Mantis, P. and Lamb, C. R. (2012), Journal of Small Animal Practice, 53: 168–173.
Hepatic lesions are often observed during ultrasonographic examination of the liver. These lesions can sometimes be benign and incidental, and in other cases evidence of serious pathology. This study retrospectively reviewed the records of 371 dogs that had had abdominal ultrasonography and abnormal liver histopathology discovered on biopsy or post mortem examination. The most common histopathological diagnosis was hepatitis, with 77 cases, followed by 47 cases of nodular hyperplasia, 45 cases of vacuolar change, and 32 cases of fibrosis. Other lesions included primary hepatic carcinoma, lymphoma, metastatic neoplasia, necrosis, lipidosis and haemangiosarcoma. Ultrasonographically, multifocal and diffuse lesions were most commonly observed. 63% of livers with haemangiosarcoma had multifocal lesions, and 71% of cases with steroid hepatopathy had diffuse lesions. Other findings included hyperechoic lesions which were common in steroid hepatopathy and lipidosis, heterogeneous lesions which were common in haemangiosarcoma, hepatomegaly which was common in steroid hepatopathy, and peritoneal fluid which was common in haemangiosarcoma. Target lesions when seen were associated with malignancy in 67% of cases. There was a marked variability in the ultrasonographic appearance of lesions with all the histopathological diagnoses, and no statistically significant associations between ultrasonographic appearance and histopathological diagnosis were noted.
This paper confirms the need for histopathological analysis of liver disease to ascertain the significance of ultrasonographic findings and achieve a diagnosis.
Dietary hyperthyroidism in dogs.
Köhler, B., Stengel, C. and Neiger-Casas, R. (2012), Journal of Small Animal Practice, 53: 182–184.
Raw food diets for dogs have a vociferous following, with various claims for their benefits, while others warn of potential risks. This paper studied thyroxine levels in dogs that were fed raw food diets. All dogs between 2006 and 2011 that presented to the authors with an elevated plasma thyroxine concentration and a history of feeding raw food were included in the study. Thyroxine, and in some cases thyroid stimulating hormone (TSH) were measured before and after diet changes. Twelve dogs were included in the study, with thyroxine levels ranging from 156 to 390 nmol/l (reference range 19-52nmol/l). TSH levels were low in the 6 dogs in which it was measured. Six dogs were noted to show signs typical of hyperthyroidism such as weight loss, aggression tachycardia and restlessness. Six dogs were asymptomatic. Following diet changes, eight dogs were re-examined, and it was found that the thyroxine concentration normalised and clinical signs resolved. The authors recommended that where increased plasma thyroxine is discovered, with or without associated clinical signs, a thorough dietary history should be obtained.
Dietary hyperthyroidism may be found in dogs that are on a raw meat diet or fed fresh or dried gullets.
Early Reherniation of Disk Material in Eleven Dogs with Surgically Treated Thoracolumbar Intervertebral Disk Extrusion.
Hettlich, B. F., Kerwin, S. C. and Levine, J. M. (2012), Veterinary Surgery, 41: 215–220.
Hemilaminectomy is often performed to treat dogs with acute thoracolumbar disc extrusion. In some cases, reherniation occurs. This retrospective case series reports 11 chondrodystrophic dogs with acute neurological decline within one week of surgical decompression of a thoraco-lumbar disc extrusion. All the dogs included in the study had a deterioration of on average 2 neurologic grades, 2-7 days after the initial hemilaminectomy. Extradural spinal cord compression was documented using computed tomography or myelography, suggestive of extruded disc material at the previous hemilaminectomy site. 10 dogs had a second surgical decompression and all improved neurologically. One dog did not undergo a second decompression, and remained deep pain negative at the follow up 6 months later.
Reherniation can occur at the site of previous hemilaminectomy, and an acute deterioration in neurologic function should lead to further investigation. Repeat surgery can lead to recovery.
Radiotherapy-induced myelosuppression in dogs: 103 cases (2002–2006).
Clermont, T., LeBlanc, A. K., Adams, W. H., LeBlanc, C. J. and Bartges, J. W. (2012), Veterinary and Comparative Oncology, 10: 24–32.
Radiotherapy has an important role in the treatment of various solid tumours. Large doses of radiation are delivered over several weeks. This paper studied 103 cases receiving 60Cobalt teletherapy for cancer. Haematological blood tests were performed, before, halfway through and at the end of treatment. Significant decreases in haematocrit, total white blood cell count, neutrophils, eosinophils, monocytes, lymphocytes and platelets were observed, but the values remained within laboratory reference ranges.
Haematological monitoring is probably not required during radiotherapy, but the changes noted in this paper may have significance where chemotherapy and radiotherapy are used together.
Bisphosphonates significantly increase the activity of doxorubicin or vincristine against canine malignant histiocytosis cells.
Hafeman, S. D., Varland, D. and Dow, S. W. (2012), Veterinary and Comparative Oncology, 10: 44–56.
Bisphosphonates are being increasingly used in veterinary medicine and oncology for example for treatment of hypercalcaemia. This in vitro study investigated the use of bisphosphonates as an adjunct to chemotherapy in the treatment of canine malignant histiocytosis, an aggressive neoplasm of macrophages and dendritic cells with a poor prognosis because of its tendency to widespread metastasis and poor sensitivity to chemotherapy. Malignant histiocytosis cell lines were treated with 6 chemotherapy and 5 bisphosphonate drugs. Clodronate and vincristine were found to elicit synergistic killing and an increase in cell cycle arrest. Zoledronate with doxorubicin also increased cell killing, and zoledronate increased the uptake of doxorubicin by malignant histiocytosis cells. The authors conclude that certain bisphosphonate drugs may increase the effectiveness of chemotherapy in the treatment of malignant histiocytosis in dogs.
This study suggests that further investigation of the usefulness of combining bisphosphonates with chemotherapy for the treatment of malignant histiocytosis is warranted.
Association of Postprandial Serum Triglyceride Concentration and Serum Canine Pancreatic Lipase Immunoreactivity in Overweight and Obese Dogs.
Verkest, K., Fleeman, L., Morton, J., Groen, S., Suchodolski, J., Steiner, J. and Rand, J. (2012), Journal of Veterinary Internal Medicine, 26: 46–53.
Hypertriglyceridaemia in dogs is suspected to increase the risk of developing pancreatitis. This study aimed to find if there was an association between postprandial serum triglyceride concentration and serum canine pancreatic lipase immunoreactivity (cPLI), a marker for pancreatic inflammation. Thirty five healthy client-owned dogs, of which 25 were overweight and 10 were obese, were included in the study. Serum triglyceride levels were measured before a meal and hourly for 12 hours after a meal. Fasting cPLI and canine trypsin-like immunoreactivity (cTLI) levels were measured. Three dogs had a fasting serum cPLI of 400ug/l or more, a concentration usually associated with evidence of pancreatic inflammation. The odds of high cPLI concentrations were 16.7 times higher in dogs that had peak postprandial triglyceride concentrations of 442mg/dl or more, compared to other dogs. Fasting triglyceride concentrations were not associated with cPLI concentrations. Over a four year follow up period, one of the dogs with a low fasting and peak postprandial triglyceride concentration developed clinical pancreatic disease, but none of the dogs with high triglyceride concentrations developed pancreatitis.
This study found that overweight and obese dogs with high peak postprandial serum triglyceride levels after a normal meal were more likely to have high serum cPLI concentrations, but this did not necessarily mean they would develop clinically important pancreatic disease.
Idiopathic Immune-Mediated Thrombocytopenia and Recent Vaccination in Dogs.
Huang, A., Moore, G. and Scott-Moncrieff, J. (2012), Journal of Veterinary Internal Medicine, 26: 142–148.
Vaccination has been implicated in causing various diseases in humans and animals, in the popular press and on the internet. One commonly cited potential consequence of vaccination in dogs is immune-mediated thrombocytopenia (ITP). This association has been demonstrated in children, but not in dogs. This retrospective case control study looked at 48 client-owned dogs with a presumed diagnosis of ITP and 96 age-matched controls with non-immune mediated disease. The median age at presentation for ITP was 7 years, with a range of 2 to 15 years. No breed association was noted. The number of dogs that were vaccinated within 42 days of the diagnosis of ITP was not statistically different than the number of dogs vaccinated within 42 days in the control group.
This study did not find evidence of a link between vaccination and ITP. However, a weak link cannot be ruled out because of the small population size.
Air sampling in the breathing zone of neonatal foals for prediction of subclinical Rhodococcus equi infection.
C. Chicken, G. Muscatello, J. Freestone, G.A. Anderson, G.F.Browning and J.R.Gilkerson Equine Veterinary Journal, 44, Issue 2: 127–250
Pneumonia caused by Rhodococcus equi is difficult to diagnose at the early stages leading to high morbidity and expensive and lengthy courses of antimicrobials. This study investigates whether air samples can be used to detect early rhodococcal pneumonia. Air samples from 53 foals of 2-10 days of age, and again from the same foals at 1-2 months. The samples were cultured and virulent R.equi isolates identified. Thoracic ultrasonography was used to definitively diagnose the presence or absence of Rhodococcal pneumonia at 1-2 months, whether or not clinical signs were present. Virulent R. equi was isolated from 19% of neonatal foals, and 45% of 1-2 month old foals, however there was no significant association between R .equi detection in air samples and ultrasonographic detection of R. equi abscesses. The majority of foals with R. equi abscesses detected ultrasonographically showed no clinical signs. The study also looked at haematological parameters of clinically infected foals and found those with rhodococcal pneumonia were more likely to have a leukocytosis than clinically normal foals. This study is interesting as the results contrast with previous studies that showed both infected foals and farms to have higher concentrations of R. equi in collected air samples.
Air sampling is not a specific method for early diagnosis of rhodococcal pneumonia in foals.
European outbreaks of atypical myopathy in grazing horses (2006-2009): Determination of indicators for risk and prognostic factors.
van Galen G, Saegarman C, Marcillaud Pitel C, Patarin F, Amory H, Baily J.D, Cassart D, Gerber V, Hahn C, Harris P, Keen J.A, Kirschvink N, Lefere L, McGorum B, Muller J.M.V, Picavet M.T.J.E, Piercy R.J, Roscher K, Serteyn D, Unger L, van der Kolk J.H, van Loon G, Verwilghen D, Westermann C.M and Votion D.M Equine Veterinary Journal
This large scale European study aims to improve diagnosis and treatment of atypical myopathy (AM) through recognition of risk factors and factors affecting prognosis. This study differs from previous studies by the inclusion of cases with similar signs, which were unlikely to have AM in order to assist in defining AM cases and to provide prognostic indicators. 600 cases were allocated to AM cases (n=354) and non AM cases (n=69), with the remainder not being included due to insufficient data. The clinical signs strongly associated with the AM group compared to the non AM group were pigmenturia, normothermia, congested mucous membranes and increased serum CK activity, the latter being variable in early cases. Positive prognostic indicators (survival rate 26%) for AM cases were cases which remained standing, normothermia, normal mucous membranes and defecation. Poor prognostic indicators included recumbency, sweating, anorexia, dyspnea, tachypnea, tachycardia. The only treatment that had a significant effect on survival was the administration of vitamins and antioxidants. This study has allowed preventative measures to be advised, these include: stabling/limited grazing during high risk periods (autumn/spring), removal of dead leaves and wood, use of flat pasture without trees and provision of supplementary food during high risk periods.
Cases with similar clinical signs to AM can be considered more likely to have AM if they have pigmenturia, normothermia, congested mucous membranes and increased serum CK activity. Those which remain standing, with normal mucous membranes and pass faeces are more likely to survive and the provision of a vitamin and antioxidant supplement is associated with survival.