A multinational survey of companion animal veterinary clinicians: How can antimicrobial stewardship guidelines be optimised for the target stakeholder?

Antimicrobial stewardship initiatives are widely regarded as a cornerstone for ameliorating the global health impact of antimicrobial resistance. Within companion animal health, such efforts have largely focused on development and dissemination of antimicrobial stewardship guidelines (ASGs). However, there have been few attempts to understand veterinarian attitudes towards and knowledge of ASGs or to determine how awareness regarding ASGs might best be increased. An online survey regarding ASGs was formulated for veterinarians who treat companion animals. The survey was distributed across 46 European and associated countries between 12 January and 30 June, 2022. In total, 2271 surveys were completed, with 64.9% of respondents (n = 1474) reporting awareness and usage of at least one ASG. Respondents from countries with greater awareness of ASGs tended to report more appropriate use of antimicrobials (Spearman's rank coefficient = 0.6084, P ≤ 0.001), with respondents from countries with country-specific ASGs tending to score highest across both awareness and appropriate use domains. Respondents prioritised guidance around antimicrobial choice (82.0%, n = 1863), duration of treatment (66.0%, n = 1499), and dosage (51.9%, n = 1179) for inclusion in future ASGs, with 78.0% (n = 1776) of respondents preferring ASGs to be integrated into their patient management system. Awareness of ASGs and their use in companion animal veterinary practice appears to be greater than previously reported, with respondents tending to report antimicrobial prescription decision making broadly in line with current clinical recommendations. However, further initiatives aimed at maximising accessibility to ASGs both within countries and individual veterinary practices are recommended.

T-cell lymphoma involving the rectum of a dog

A mediastinal mass was diagnosed in a 7-year-4-month-old neutered female mixed breed dog following a 3-week history of lethargy, hyporexia and pyrexia. Bi-cavitary imaging, needle aspirate cytology and flow cytometry confirmed WHO clinical stage IVb, intermediate to large T-cell lymphoma involving the mediastinum, liver and spleen. The dog initially responded to a multidrug chemotherapy protocol but clinical deterioration occurred 3 months later. The dog presented with anorexia, vomiting and diarrhoea, associated with marked faecal tenesmus and haematochezia, initially believed by the primary care practitioner to be related to chemotherapy toxicity. However, rectal examination revealed multiple sessile and pedunculated masses. Further diagnostic imaging, cytology and flow cytometry confirmed progressive disease, including T-cell lymphoma of the rectum. Histology and immunohistochemistry confirmed an infiltrate of intermediate-sized CD3-positive neoplastic cells that expanded the rectal mucosa. Rectal lymphoma is uncommon in dogs and previous cases have been B cell in origin. In this report we describe the clinical presentation and macro- and microscopic findings of a case of canine T-cell lymphoma involving the rectum.

Serum amyloid A and other clinicopathological variables in cats with intermediate- and large-cell lymphoma

OBJECTIVES

Serum amyloid A (SAA) concentrations are increased in cats with lymphoma vs healthy cats; however, the association between SAA concentrations and prognosis in cats with lymphoma is unclear. The aim of this study was to evaluate if SAA concentrations were different in cats with nasal vs non-nasal lymphoma, if SAA concentrations are prognostic in patients treated with high-dose chemotherapy and if SAA concentrations are correlated with other clinicopathological variables.

METHODS

Cats diagnosed with intermediate- or large-cell lymphoma between 2012 and 2022 with SAA concentration data available were included. Associations between tumour site (nasal vs non-nasal), stage, response to treatment and SAA concentration were evaluated using non-parametric statistics. Associations between SAA concentrations and stage with survival time were evaluated using Cox regression analysis. Patients with nasal tumours and those not receiving high-dose chemotherapy were excluded from the survival analyses.

RESULTS

Thirty-nine cats were included. Median SAA concentrations were significantly higher in non-nasal compared with nasal lymphoma (42 µg/ml [range <0.3-797] vs <0.3 µg/ml [range <0.3-0.9]; P = 0.026). SAA concentrations did not correlate with tumour stage. Median survival time for patients with non-nasal tumour and undergoing chemotherapy was 49 days (range 2-1726). Responders had a better median survival time than non-responders (273 days [range 43-1728] vs 39 days [range 2-169]; P <0.001), whereas SAA concentrations were not associated with survival time. Lower haematocrit at presentation was associated with a reduced median survival time (P = 0.007).

CONCLUSIONS AND RELEVANCE

In the population examined, no correlation between serum concentration of SAA and prognosis in patients with lymphoma was identified, while low haematocrit and lack of response to treatment were both found to be associated with survival time. SAA concentrations were elevated in patients with non-nasal lymphoma vs patients with tumours confined to the nasal cavity.

Rapid in-house method of CSF analysis utilising sedimentation direct from the spinal needle

OBJECTIVES

To establish the utility of a novel in-house method of CSF analysis using sedimentation cytology direct from the spinal needle for the detection of laboratory-defined pleocytosis.

MATERIALS AND METHODS

In dogs and cats undergoing routine CSF analysis for investigation of neurological signs, an additional preparation was made at the patient's side by inverting the spinal needle on a slide and sedimenting for at least 1 hour. Nucleated cellularity and differential counts were assessed and compared with "gold-standard" analysis. Variability of cell counts between observers and within slides using the new method was evaluated to optimise the procedure.

RESULTS

Using a ×50 objective, at least 10 fields and an average of more than five cells per field were considered appropriate guidelines to achieve correct classification of samples (normal or pleocytosis). The new method had high sensitivity (89%) and specificity (100%) for the detection of laboratory-defined pleocytosis. Agreement on the type of pleocytosis was good.

CLINICAL SIGNIFICANCE

Clinically useful information can be obtained from CSF samples in a patient-side setting without additional equipment. This technique may be of benefit if little fluid is available or if logistical constraints limit the availability of rapid specialist results.

Non-laxative CT colonography with barium-based faecal tagging: is additional phosphate enema beneficial and well tolerated?

OBJECTIVE

The purpose of this study was to investigate the efficacy and tolerance of an additional phosphate enema prior to non-laxative CT colonography (CTC).

METHODS

71 patients (mean age 80 years, 28 male, 43 female) underwent non-laxative CTC following 4 oral doses of diluted 2% w/w barium sulphate. Patients were invited to self-administer a phosphate enema 2 h before CTC. An experienced observer graded the volume of retained stool (1 (nil) to 4 (>75% bowel circumference coated)), retained fluid ((1 (nil) to 4 (>50% circumference obscured)), retained stool tagging quality (1 (untagged) to 5 (≥75% to 100%) tagged) and confidence a polyp ≥6 mm could be excluded (yes/no) for each of six colonic segments. Tolerance of the enema was assessed via questionnaire. Data were analysed between those using and not using the enema by Mann-Whitney and Fisher's exact test. 18/71 patients declined the enema.

RESULTS

There was no reduction in residual stool volume with enema use compared with non-use either overall (mean score 2.6 vs 2.7, p = 0.76) or in the left colon (mean 2.3 vs 2.4, p = 0.47). Overall tagging quality was no different (mean score 4.4 vs 4.3, p = 0.43). There was significantly more retained left colonic fluid post enema (mean score 1.9 vs 1.1, p<0.0001), and diagnostic confidence in excluding polyps was significantly reduced (exclusion not possible in 35% segments vs 21% without enema, p = 0.006). Of 53 patients, 30 (56%) found the enema straightforward to use, but 4 (8%) found it unpleasant.

CONCLUSION

Phosphate enema use prior to non-laxative CTC leads to greater retained fluid, reducing diagnostic confidence, and is not recommended.

A comparison of techniques to optimize measurement of voltage changes in electrical impedance tomography by minimizing phase shift errors

In electrical impedance tomography, errors due to stray capacitance may be reduced by optimization of the reference phase of the demodulator. Two possible methods, maximization of the demodulator output and minimization of reciprocity error have been assessed, applied to each electrode combination individually, or to all combinations as a whole. Using an EIT system with a single impedance measuring circuit and multiplexer to address the 16 electrodes, the methods were tested on resistor-capacitor networks, saline-filled tanks and humans during variation of the saline concentration of a constant fluid volume in the stomach. Optimization of each channel individually gave less error, particularly on humans, and maximization of the output of the demodulator was more robust. This method is, therefore, recommended to optimize systems and reduce systematic errors with similar EIT systems.

Dose reduction in evacuation proctography

The goal of this study was to reduce the patient radiation dose from evacuation proctography. Ninety-eight consecutive adult patients referred for proctography to investigate difficult rectal evacuation were studied using a digital imaging system with either a standard digital program for barium examinations, a reduced dose digital program (both with and without additional copper filtration), or Video fluoroscopy. Dose-area products were recorded for each examination and the groups were compared. All four protocols produced technically acceptable examinations. The low-dose program with copper filtration (median dose 382 cGy cm2) and Video fluoroscopy (median dose 705 cGy cm2) were associated with significantly less dose than other groups (p < 0.0001). Patient dose during evacuation proctography can be reduced significantly without compromising the diagnostic quality of the examination. A digital program with added copper filtration conveyed the lowest dose.

Cisapride or metoclopramide to accelerate small bowel transit during barium follow-through examination?

BACKGROUND

Metoclopramide is commonly used to accelerate small bowel transit during barium follow-through (BaFT) examinations, but its action is unpredictable. Cisapride, commonly used to treat gastroesophageal reflux disease, also accelerates small bowel transit and may be a viable alternative. The two were compared in a prospective, randomized, blind study.

METHODS

Patients attending for BaFT were randomized to receive either 10 mg cisapride or 20 mg metoclopramide orally 1 h before the barium suspension. BaFT was performed by using a standard technique, and small bowel transit and study quality were compared. Patients also noted any side effects experienced.

RESULTS

Of 45 patients recruited, 27 received cisapride and 18 metoclopramide. Median transit time for the cisapride group was 30 min (range = 10-130 min) versus 67.5 min (range = 30-290 min) for the metoclopramide group (p = 0.019). Study quality was comparable. However, nine patients (33%) receiving cisapride experienced nausea versus only one subject (6%) receiving metoclopramide (p = 0.034).

CONCLUSIONS

This study suggests that cisapride is a more effective prokinetic agent than metoclopramide, but this benefit is offset by a higher incidence of side effects.

A semi-automated method for 5'-ectonucleotidase measurement in lymphocytes

We describe a simple, non-radioactive, semi-automated method for measuring lymphocyte ecto-5'-nucleotidase activity in isolated cell homogenates. The method which uses inosine 5'-monophosphate (IMP) as a substrate was optimized and requires a total of 4 x 10(6) lymphocytes. The reference range obtained (38.7-180.0 nmol/h per mg protein; means = 106.6) agrees with other isotopic methods which use 14C-IMP. The simplicity, sensitivity (lower limit 10, upper limit 400 nmol/h per mL) and precision (at 114 nmol/h per mL, interday 4.2% s.d., n = 20; intraday 5.8%, n = 10) makes this method suitable for routine clinical laboratory use.

Lymphocyte ectoenzyme activity compared in healthy persons and patients seropositive to or at high risk of HIV infection

We measured two ectoenzymes, ecto-5'-nucleotidase (NT) and dipeptidyl peptidase IV (DP) in the peripheral blood lymphocytes of various groups of HIV-infected patients because of the previous implied relationship of these enzymes to immune function. NT expressed as mean nmol/h per mg protein (+/- s.d.) was significantly depressed in the HIV-seropositive asymptomatic (42 +/- 32; P less than 0.01) and AIDS groups (14 +/- 7; P less than 0.002) when compared with a healthy HIV-seronegative male population (83 +/- 27). The NT activities in asymptomatic HIV-seropositive and HIV-seronegative high risk groups (53 +/- 30) were not significantly different from one another but both groups had significantly higher enzyme activities than the AIDS group (P = 0.01 and less than 0.002, respectively). The seronegative high risk and normal healthy group had similar NT activities. DP activities expressed as mean nmol/h per mg protein (+/- s.d.) in both seropositive asymptomatic (0.188 +/- 0.038) and high risk seronegative (0.180 +/- 0.05) groups had higher enzyme activities than the healthy seronegative (0.117 +/- 0.015; P = 0.02 and 0.05, respectively) and AIDS group (0.096 +/- 0.036; P = 0.002 and 0.02, respectively). The healthy seronegative group had DP activities not significantly different to the AIDS groups. Similarly the high risk seronegative and healthy seropositive group had similar DP activities. These results taken together indicate that measurement of both DP and NT should be evaluated prospectively as a monitor of the clinical progression of HIV infection.

Nonpenetrating traumatic rupture of the tricuspid valve. Formation of ventricular septal aneurysm and subsequent septal necrosis: recognition by two-dimensional Doppler echocardiography

A 26-year old man was admitted with blunt trauma to the chest following a high-speed deceleration injury. A two-dimensional Doppler echocardiogram demonstrated traumatic rupture of the tricuspid valve and a hematoma in the basilar portion of the interventricular septum. Serial two-dimensional Doppler echocardiographic analyses demonstrated evolutionary formation of a septal aneurysm and subsequent rupture with formation of a ventricular septal defect. The usefulness of the two-dimensional Doppler echocardiogram as a screening tool for cardiac contusion is discussed.

Characterization of myocardial infarcts in the rat

In 42 male Sprague-Dawley rats, the distribution of coronary arteries, the geometry of myocardial infarcts (MIs) and the involvement of the left ventricular papillary and trabecular muscles, after left coronary occlusion, were investigated. The septal branch was found to be responsible for the blood supply to the septum and, thus, occlusion of the left coronary artery, which spares the septal branch, results in an infarct that does not include the interventricular wall. Myocardial infarct size was measured by planimetry of histologic sections of serial slices of the left ventricle. There was no difference between the average percent of subepicardial (43% +/- 1%) and subendocardial (44% +/- 3%) infarction when the whole left ventricle was considered. Analysis of individual slices had shown that the infarcts comprised a greater percentage of left ventricular circumference at the apex than at the base in both layers of the myocardium. Toward the apex, more subendocardium was infarcted than subepicardium. The papillary and trabecular muscles are minimally involved in 75% of infarcts.