Herdan C L, Acke E, Dicken M, Archer R M, Forsyth S F, Gee E K, Pauwels F E T
Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston, New Zealand.
N Z Vet J. 2012 Sep;60(5):297-304. doi: 10.1080/00480169.2011.651702. Epub 2012 Apr 16.
Three Thoroughbred horses, a 6-week-old filly (Case 1), a 15-year-old broodmare (Case 2) and a yearling filly (Case 3), sustained synovial sepsis secondary to trauma.
Case 1 presented with a heel bulb laceration communicating with the distal interphalangeal joint. Arthroscopic lavage was performed and treatment commenced using systemic and local broad spectrum antimicrobial drugs. A pure growth of multi-drug-resistant (MDR) Enterococcus gallinarum was cultured from samples of synovium and joint fluid. Antimicrobial treatment was changed according to the susceptibility results. Response to treatment was poor and despite repeat arthroscopic lavage and intra-osseous regional perfusion of antimicrobials the filly was subject to euthanasia 24 days after the initial injury. Post-mortem examination confirmed septic synovitis, cartilage degeneration and osteomyelitis. Case 2 sustained a full thickness wound to the carpus which was sharply debrided and closed. The wound dehisced with effusion within the tendon sheath. Drainage was established and treatment included systemic broad spectrum antimicrobials, topical lavage with povodine-iodine and manuka honey infusion. A mixed infection including MDR Enterococcus faecalis was cultured from the synovial fluid. Antebrachiocarpal joint effusion developed 21 days after initial injury and joint sepsis was confirmed. Arthroscopic lavage and tendon sheath debridement were performed, followed by treatment with systemic and local antimicrobials. The mare improved and was discharged. Three months later lameness recurred and corticosteroids were administered intra-articularly. The mare became non-weight bearing lame and was subject to euthanasia. Post-mortem examination confirmed joint sepsis of the antebrachiocarpal and intercarpal joint. Case 3 presented with a complete articular open fracture of the tibial crest. Under general anaesthesia the fracture was stabilised and the wounds debrided and closed. Systemic broad-spectrum antimicrobials were administered. Six days later the wound dehisced and a bone fragment was removed. Three weeks post-surgery the wound deteriorated with a purulent discharge. Culture of the discharge revealed a mixed bacterial infection, including a MDR Enterococcus faecalis. Femoropatellar joint involvement was confirmed, and treatment included joint lavage, local and systemic antibiosis, and manuka honey instilled into the wound. The filly initially improved, and then deteriorated such that euthanasia was performed.
All three cases had synovial sepsis with MDR Enterococcus spp.
Increased awareness of MDR pathogens in equine wound infections is essential. Prompt diagnostic testing, appropriate therapy, infection control strategies and on-going monitoring and management are vital to limit the clinical impact of these organisms.
三匹纯种马，一匹6周龄的小母马（病例1）、一匹15岁的母马（病例2）和一匹一岁的小母马（病例3），继发于创伤后发生滑膜败血症。
病例1表现为足跟球部撕裂伤并与远侧指间关节相通。进行了关节镜灌洗，并开始使用全身和局部广谱抗菌药物治疗。从滑膜和关节液样本中培养出多药耐药（MDR）鹑鸡肠球菌的纯培养物。根据药敏结果更改抗菌治疗。治疗反应不佳，尽管重复进行关节镜灌洗和抗菌药物的骨内区域灌注，这匹小母马在初次受伤后24天实施了安乐死。尸检证实为化脓性滑膜炎、软骨退变和骨髓炎。病例2腕关节出现全层伤口，进行了锐性清创并缝合。伤口裂开，腱鞘内有积液。建立了引流，治疗包括全身广谱抗菌药物、聚维酮碘局部灌洗和麦卢卡蜂蜜灌注。从滑液中培养出包括MDR粪肠球菌在内的混合感染。初次受伤21天后出现前臂腕关节积液，确诊为关节败血症。进行了关节镜灌洗和腱鞘清创，随后用全身和局部抗菌药物治疗。这匹母马病情好转并出院。三个月后跛行复发，关节内注射了皮质类固醇。这匹母马出现非负重性跛行并实施了安乐死。尸检证实为前臂腕关节和腕间关节的关节败血症。病例3表现为胫骨嵴完全关节开放性骨折。在全身麻醉下对骨折进行了固定，对伤口进行了清创和缝合。给予全身广谱抗菌药物。六天后伤口裂开，取出一块骨碎片。手术后三周伤口恶化并伴有脓性分泌物。分泌物培养显示为混合细菌感染，包括MDR粪肠球菌。确诊为股髌关节受累，治疗包括关节灌洗、局部和全身抗感染，以及向伤口内滴注麦卢卡蜂蜜。这匹小母马最初病情好转，随后恶化，最终实施了安乐死。
所有三个病例均为伴有MDR肠球菌属的滑膜败血症。
提高对马伤口感染中MDR病原体的认识至关重要。及时的诊断检测、适当的治疗、感染控制策略以及持续的监测和管理对于限制这些病原体的临床影响至关重要。
