Diagnostic findings in sinonasal aspergillosis in dogs in the United Kingdom: 475 cases (2011-2021).

OBJECTIVES: To describe the diagnostic tests used and their comparative performance in dogs diagnosed with sinonasal aspergillosis in the United Kingdom. A secondary objective was to describe the signalment, clinical findings and common clinicopathologic abnormalities in sinonasal aspergillosis. MATERIALS AND METHODS: A multi-centre retrospective survey was performed involving 23 referral centres in the United Kingdom to identify dogs diagnosed with sinonasal aspergillosis from January 2011 to December 2021. Dogs were included if fungal plaques were seen during rhinoscopy or if ancillary testing (via histopathology, culture, cytology, serology or PCR) was positive and other differential diagnoses were excluded. RESULTS: A total of 662 cases were entered into the database across the 23 referral centres. Four hundred and seventy-five cases met the study inclusion criteria. Of these, 419 dogs had fungal plaques and compatible clinical signs. Fungal plaques were not seen in 56 dogs with turbinate destruction that had compatible clinical signs and a positive ancillary test result. Ancillary diagnostics were performed in 312 of 419 (74%) dogs with observed fungal plaques permitting calculation of sensitivity of cytology as 67%, fungal culture 59%, histopathology 47% and PCR 71%. CLINICAL SIGNIFICANCE: The sensitivities of ancillary diagnostics in this study were lower than previously reported challenging the clinical utility of such tests in sinonasal aspergillosis. Treatment and management decisions should be based on a combination of diagnostics including imaging findings, visual inspection, and ancillary testing, rather than ancillary tests alone.

Diagnostic imaging findings in a referral population of dogs diagnosed with immune-mediated haemolytic anaemia: 50 cases (2015-2018).

OBJECTIVES: To describe and characterise changes documented on thoracic and abdominal imaging of dogs with confirmed immune-mediated haemolytic anaemia. MATERIALS AND METHODS: Medical records from a referral hospital were searched from 2015 to 2018 for all dogs diagnosed with immune-mediated haemolytic anaemia that underwent thoracic and abdominal imaging by radiography, ultrasound or computed tomography. RESULTS: Fifty dogs were included. Thoracic imaging revealed abnormalities in 10 dogs (20%) of which lymphadenopathy and cardiomegaly were documented in four dogs (8%) each, and pleural effusion and pleural thickening in one dog (2%) each. Abdominal imaging revealed abnormalities in 43 dogs (86%), in which hepatomegaly and peritoneal effusion were documented in 20 (40%) and 19 dogs (38%), gallbladder wall thickening and sludge in 16 (32%) and 14 dogs (28%) and splenic nodules and splenomegaly in 13 (26%) and seven dogs (14%), respectively. Hepatic and splenic abnormalities were further investigated via fine needle aspirates in 18 dogs and revealed extramedullary haematopoiesis in 12 hepatic (66.7%) and 14 splenic (77.8%) fine needle aspirate samples. Cholecystocentesis was performed in nine dogs with gallbladder abnormalities and revealed bactibilia in three samples (33.3%). CLINICAL SIGNIFICANCE: In this population of dogs with immune-mediated haemolytic anaemia, thoracic imaging abnormalities were uncommon. Hepatomegaly, peritoneal effusion and gallbladder wall thickening were the most common abdominal imaging findings with bactibilia confirmed in one third of collected bile samples. Hepatosplenomegaly and abdominal lymphadenopathy were not associated with neoplasia in any of the dogs included in this study.

Evaluation of snake envenomation-induced renal dysfunction in dogs using early urinary biomarkers of nephrotoxicity.

Renal dysfunction in dogs envenomed by poisonous snakes is currently detected using traditional serum and urinary biomarkers such as creatinine and proteinuria. However, these markers lack sensitivity at the early stages of renal dysfunction and their diagnostic accuracy is affected by pre-analytical factors commonly occurring in these dogs, such as haemolysis and haemoglobinuria. Early detection of renal dysfunction would allow for the identification of dogs requiring intensive treatment and monitoring and may help inform prognosis. The aim of this study was to evaluate the performance of several novel urinary biomarkers of glomerular dysfunction, namely, urinary albumin (uAlb), immunoglobulin G (uIgG) and C-reactive protein (uCRP) and of proximal tubular dysfunction (urinary retinol binding protein (uRBP)) compared to traditional end points in dogs with renal damage caused by snake envenomation. Biomarker results were compared between 19 dogs bitten by snakes producing either neurotoxins or cytotoxins and 10 clinically healthy controls. uAlb, uIgG, and uRBP were significantly increased in snake-envenomed dogs at presentation compared to controls, whereas only uIgG and uCRP were significantly elevated 24h post-envenomation. The urinary protein:creatinine ratio was also increased in envenomed dogs compared to controls, but because of the presence of haematuria and haemoglobinuria, differentiation between pre-renal and renal proteinuria was not possible. The results showed that these novel urinary biomarkers may assist in better detecting renal dysfunction in dogs envenomed by poisonous snakes at the acute disease stage compared to traditional laboratory endpoints.

Backbone dynamics of oxidized and reduced D. vulgaris flavodoxin in solution.

Recombinant Desulfovibrio vulgaris flavodoxin was produced in Escherichia coli. A complete backbone NMR assignment for the two-electron reduced protein revealed significant changes of chemical shift values compared to the oxidized protein, in particular for the flavine mononucleotide (FMN)-binding site. A comparison of homo- and heteronuclear NOESY spectra for the two redox states led to the assumption that reduction is not accompanied by significant changes of the global fold of the protein. The backbone dynamics of both the oxidized and reduced forms of D. vulgaris flavodoxin were investigated using two-dimensional 15N-1H correlation NMR spectroscopy. T1, T2 and NOE data are obtained for 95% of the backbone amide groups in both redox states. These values were analysed in terms of the 'model-free' approach introduced by Lipari and Szabo [(1982) J. Am. Chem. Soc., 104, 4546-4559, 4559-4570]. A comparison of the two redox states indicates that in the reduced species significantly more flexibility occurs in the two loop regions enclosing FMN. Also, a higher amplitude of local motion could be found for the N(3)H group of FMN bound to the reduced protein compared to the oxidized state.