The intestinal microbiome in dogs and cats with diarrhoea as detected by a faecal polymerase chain reaction-based panel in Perth, Western Australia.

This study reports the prevalence of potential faecal pathogens in the microbiome detected in a cohort of cats and dogs with diarrhoea in Perth, Western Australia. Records from a commercial diagnostic laboratory using faecal PCR testing between July 2014 and August 2015 were reviewed.Of 289 feline faecal samples reviewed, Salmonella spp. (1.7%), Campylobacter spp. (47.6%), Clostridium perfringens (81.3%), Giardia spp. (11.1%), Toxoplasma gondii (1.2%), Tritrichomonas foetus (4.8%), panleukopenia virus (6.5%) and coronavirus (39.5%) were detected. In dogs, Salmonella spp. (5.4%), Campylobacter spp. (36.3%), C. perfringens (85.4%), Giardia spp. (6.2%), parvovirus (9.4%), coronavirus (4.7%) and distemper virus (1.5%) were detected.

Prevalence of bacteriuria in dogs without clinical signs of urinary tract infection presenting for elective surgical procedures.

OBJECTIVES: To determine the frequency of bacteriuria in dogs presenting for elective surgery, to compare the frequency of bacteriuria in dogs presenting for orthopaedic (non-neurological) procedures to that of dogs presenting for soft tissue procedures and to measure the agreement of microscopic visualisation of bacteria in urine sediment with the occurrence of bacterial growth on culture. METHODS: Prospective cohort study of 140 client-owned dogs. Urine was collected via prepubic cystocentesis prior to or immediately after induction of anaesthesia. Urine was submitted for quantitative bacteriological culture and urinalysis. The dogs' age, sex, weight and breed were recorded, as well as the surgical procedure performed. RESULTS: In total, 80 orthopaedic and 60 soft tissue surgical cases were included in the study; 3 dogs (2.1%) returned bacterial growth on culture (positive urine culture) and 19 (13.6%) recorded urine sediment with pyuria and/or bacteriuria on urinalysis (positive urinalysis). All dogs with positive urine culture were female and two of them underwent orthopaedic procedures. Each bitch had growth of Escherichia coli >10(5) CFU/mL. The agreement between positive urinalysis and positive urine culture was poor (κ = 0.15). CONCLUSIONS: The prevalence of bacteriuria in dogs without clinical signs of urinary tract infection in this population was low (2.1%). An at-risk population could not be identified because of the small number of positive outcomes. A positive urinalysis showed poor agreement with urine culture results and therefore the decision to treat without performing a urine culture is not advised.

Etoposide as a virocidal anticytomegalovirus therapy: intravitreal toxicology and pharmacology in rabbits.

BACKGROUND: Although Cytomegalovirus (CMV) retinitis is now a common intraocular infection, current therapy is only virostatic so ongoing treatment is required. Etoposide was found to be virocidal for CMV in laboratory experiments and it might prove to be beneficial clinically. We investigated the toxicity and intraocular concentration of etoposide (VP16) and its new analogue etoposide-phosphate (VP16P) following intravitreal injections in rabbit eyes. METHODS: First a sequential dose-response was assessed with flash electroretinogram for both eyes of light- and dark-adapted rabbits (n = 7; one rabbit for each dose) over a range of light intensities before and after intravitreal injection of VP16 or VP16P to one eye; the other eye was injected with normal saline as a control. A multidose study was then performed on four rabbits. A non-toxic dose of VP16P (50 or 75 g) was injected into the vitreous of one eye on four occasions 1 week apart. A photopic electroretinogram was performed before the first injection and 6 weeks after the last injection. All the eyes from the electroretinogram studies were fixed in formalin, placed in paraffin, then stained with haematoxylin and eosin and examined under a light microscope. To determine the time-course of the intraocular concentrations of VP16P a sequential pharmacokinetic study was performed using a further 12 rabbits. Each rabbit was injected with 50 g VP16P to one eye and 75 g VP16P to the other eye. Three of these rabbits were killed at 1, 3, 6 and 9 h after injection. Samples of vitreous were assayed for both VP16 and VP16P using HPLC. An in vitro dose response assay was performed using third-passage bovine retinal pigment epithelial (RPE) cells cultured in Dulbecco's modified Eagles medium with fetal calf serum. The effect of a log-dose increment of VP16P on the RPE cell proliferation was assessed using tritiated thymidine incorporation. RESULTS: The electroretinogram studies suggested that VP16 was toxic even with the 10 g dose. For VP16P a toxic effect was noted following injection of a single dose greater than 100 g. Multiple injections of 50 or 75 g VP16P did not produce a toxic response. Histological examination demonstrated significant abnormality only with the 500 g dose of VP16 or VP16P. VP16P was rapidly metabolized to VP16 in the eye, producing concentrations of 2.0 g/mL or more for up to 9 h following a 75-microg dose. This suggests that the electroretinogram findings following VP16 injections were confounded by a toxic effect of the ethanol solvent (which is absent from the VP16P preparation). VP16P was quite potent, the ID50 was about 0.1 g/mL for bovine RPE cells in the in vitro assay. DISCUSSION: These results indicate that multiple 75-gVP16P intravitreal injections were not toxic to the rabbit eye and provide a therapeutic intraocular concentration for up to 9 h after the injection.

Effect of high glucose on permeability of retinal capillary endothelium in vitro.

PURPOSE: To study the effect of high glucose on the permeability of bovine retinal capillary endothelial cell (BRCEC) monolayers. METHODS: The paracellular permeability of second-passage BRCEC cultured on millipore filters in two chamber transwell inserts was assayed by measuring the peak trans-monolayer electrical resistance and percent equilibration of 14C-inulin 48 hours after it had been added to the luminal chamber. RESULTS: High glucose increased the paracellular permeability of BRCEC monolayers independently of its hypertonic action (5 mM glucose: 154.2 +/- 21.2 and 19.5 +/- 2.4; 30 mM glucose: 134.2 +/- 5.1 [P = 0.01] and 23.5 +/- 2.1 [P = 0.01]; 5 mM glucose + 25 mM mannitol: 168.7 +/- 13.7 ohm.cm2 [P = 0.04] and 19.3% +/- 1.2% 48-hour equilibration of inulin [P = 0.008]). In a separate series of experiments, the authors were unable to show that either aminoguanidine or ponalrestat prevented the effect of high glucose on permeability (30 mM glucose 95.1 +/- 16.7 and 45.4 +/- 5.6; 5 mM glucose: 122.9 +/- 14.2 [P = 0.02] and 36.6 +/- 5.6 [P = 0.001]; 30 mM glucose + aminoguanidine 87.9 +/- 17.5 [P = 0.04] and 75.3 +/- 14.9 [P = 0.6]; 30 mM glucose + ponalrestat 79.9 +/- 12.7 ohm.cm2 [P = 0.1] and 48.2 +/- 2.5% 48-hour equilibration of inulin [P = 0.15]). Ponalrestat did not abrogate the effect of high glucose despite its ability to reduce a high glucose-induced increase in BRCEC intracellular sorbitol levels. CONCLUSIONS: The data are consistent with a role for increased paracellular permeability in breakdown of the blood-retinal barrier in diabetic retinopathy, which appears to be independent of both nonenzymatic glycosylation and the polyol pathway.