Case Report: Toxigenic Corynebacterium ulcerans Diphtheria-Like Infection in a Horse in the United Kingdom.

Corynebacterium ulcerans (C. ulcerans) may cause diphtheria in humans and can be carried by a wide range of animal species including dairy cows and, more recently, dogs and cats that have been increasingly involved in zoonotic trasmission. We isolated and characterized, by WGS, a toxigenic C. ulcerans strain from a diseased horse in the United Kingdom showing clinical signs of respiratory diphtheria comparable to those seen in people. Our results indicate a role for horses as reservoirs for zoonotic C. ulcerans.

Ultrasonographic guidance for perineural injections of the cervical spinal nerves in horses.

OBJECTIVE: To evaluate the accuracy of ultrasonographic guidance for injection near the ventral rami of the cervical spinal nerves (VRCSN). STUDY DESIGN: Ex vivo study. SAMPLE POPULATION: Ten cadavers (n = 40 injections). METHODS: Left and right VRCSN at C4/5 and C5/6 were infiltrated at the intervertebral foramen (IVF) under ultrasonographic guidance. A vertically orientated 3.5-MHz curvilinear probe was used to identify the craniocaudal midpoint of the articular process joint (APJ). The probe was moved ventrally until the IVF was identified. An 18-gauge 15-cm-long spinal needle was aimed immediately below the ventral margin of the cranial articular process, where 1 mL of latex was injected. Cadavers were dissected, and the location of the latex was recorded relative to the ventral ramus, the spinal cord, and the vertebral artery. RESULTS: Direct infiltration of the ventral ramus occurred in 73% (29/40) of injections; 15% (6/40) of injections were < 0.5 cm from the ventral ramus, and 13% (5/40) of injections were > 0.5 cm (maximum 1.5 cm). Latex was located at a mean of 2.4 cm (range, 0.8-4) from the spinal cord and 0.9 cm (range, 0-1.5) from the vertebral artery. CONCLUSION: Ultrasonographic guidance of perineural injections of the caudal VRCSN was repeatable and accurate, with 88% of injections located within 0.5 cm of the ventral ramus. Iatrogenic damage was limited to one penetration into the vertebral artery. CLINICAL SIGNIFICANCE: Ultrasonographic guidance of perineural injections of the caudal VRCSN may be considered by operators experienced in cervical APJ scanning in horses with suspected cervical spinal nerve compression.

Can blood serum amyloid A concentrations in horses differentiate synovial sepsis from extrasynovial inflammation and determine response to treatment?

BACKGROUND: Serum amyloid A (SAA) concentrations in blood and synovial fluid of horses with synovial sepsis have diagnostic value. Studies suggest serial blood SAA measurements could act as a prognostic indicator. This study evaluated the use of serial blood SAA concentrations for monitoring of horses with synovial sepsis. METHODS: A prospective clinical trial was performed of horses referred to a single hospital with synovial sepsis that survived (n=17), synovial sepsis that were euthanised (n=5), non-septic intrasynovial pathologies (n=14) or extensive extrasynovial lacerations (n=5). SAA concentrations were determined on admission and every 24 hours thereafter. The area under the concentration-time curve from 0 to 144 hours of each group was compared by Kruskal-Wallis and post hoc Dunn's tests (P<0.05). RESULTS: Significant difference in mean blood concentration of SAA was found between synovial sepsis that survived and non-septic pathologies in the first 48 hours, as well as between non-septic intrasynovial pathologies and non-responsive sepsis requiring euthanasia. No difference was found between extensive extrasynovial lacerations and any septic group. CONCLUSIONS: While serial blood SAA is useful for monitoring clinical response of intrasynovial septic pathologies, interpretation should consider other clinical findings since blood SAA is not a specific marker for synovial sepsis.

Ex vivo comparison of barbed sutures for pelvic flexure enterotomy in horses.

OBJECTIVE: To evaluate two different barbed sutures for closure of pelvic flexure enterotomies and compare results achieved with two previously described closure techniques. STUDY DESIGN: Ex vivo. SAMPLE POPULATION: Twenty-four fresh cadaver adult equine large colons. METHODS: Cadavers were randomly assigned to four closure groups (n = 6 each group): single-layer absorbable suture, double-layer absorbable suture, single-layer unidirectional barbed suture, or single-layer bidirectional barbed suture. Construction time, luminal reduction (percentage), bursting pressure, and method of failure were measured. Cost, leakage, exposed suture, and general appearance were recorded. Comparisons were performed with one-way analysis of variance and post hoc Bonferroni test (P < .05). RESULTS: Double-layer absorbable closure had the highest bursting pressure (mean = 178.5 mm Hg, SD = 9.79, P < .001) but took more time (P = .001) compared with all other groups. The construction time of both barbed suture closures did not differ from the single-layer closure (P > .06). Bursting strengths of both unidirectional (mean = 91.6 mm Hg, SD = 5.57) and bidirectional (mean = 87.5 mm Hg, SD = 8.69) barbed sutures were lower (P > .006 for both) than those of both single- (mean = 117.6 mm Hg, SD = 11.69) and double-layer (mean = 178.5 mm Hg, SD = 9.79) closures. Unidirectional barbed suture closure had a reduction in lumen diameter (P = .004) compared with bidirectional and single-layer closures. CONCLUSION: Enterotomy closures with the two different barbed suture patterns were comparable in bursting strength and construction time. However, the barbed suture patterns had lower bursting strength compared with traditional single- and double-layer closures. Unidirectional barbed suture closure also reduced lumen diameter. CLINICAL SIGNIFICANCE: Closure of a large colon enterotomy with barbed suture patterns may be less secure than single- and double-layer suture closure.