Necrotising fasciitis associated with Escherichia coli in a dog

CASE HISTORY: Lameness and limb pain associated with a laceration in the inner thigh of a Border Collie dog progressed over 4 days to extensive necrosis of the full-thickness of skin and subcutaneous (S/C) tissue. A successful outcome was achieved using surgical debridement and intensive supportive care, followed by limited local closure, axial pattern flap development, and free skin grafting. CLINICAL FINDINGS: Clinical findings included severe pain, depression, pyrexia and hypoalbuminaemia, and full-thickness loss of skin from the caudal thigh to the hock. Histopathologically, debrided tissue showed extensive necrosis of the dermis, adipose and muscle tissues, and the presence of numerous Gram-negative rods. Escherichia coli was cultured from deep tissue samples. DIAGNOSIS: Necrotising fasciitis (NF) associated with E. coli infection. CLINICAL RELEVANCE: NF associated with E. coli has not been previously reported in dogs. The importance of early diagnosis and surgical debridement is noted and the relevant medical literature is reviewed.     

Necrotising fasciitis associated with Escherichia coli in a dog

CASE HISTORY: Lameness and limb pain associated with a laceration in the inner thigh of a Border Collie dog progressed over 4 days to extensive necrosis of the full-thickness of skin and subcutaneous (S/C) tissue. A successful outcome was achieved using surgical debridement and intensive supportive care, followed by limited local closure, axial pattern flap development, and free skin grafting.

CLINICAL FINDINGS: Clinical findings included severe pain, depression, pyrexia and hypoalbuminaemia, and full-thickness loss of skin from the caudal thigh to the hock. Histopathologically, debrided tissue showed extensive necrosis of the dermis, adipose and muscle tissues, and the presence of numerous Gram-negative rods. Escherichia coli was cultured from deep tissue samples.

DIAGNOSIS: Necrotising fasciitis (NF) associated with E. coli infection.

CLINICAL RELEVANCE: NF associated with E. coli has not been previously reported in dogs. The importance of early diagnosis and surgical debridement is noted and the relevant medical literature is reviewed.     

Fournier's gangrene in a cat

Objective – To describe the clinical course of a cat diagnosed with Fournier's gangrene.
Case Summary – A 2-year-old castrated male cat was presented to an emergency hospital for evaluation of acute onset of lethargy, mucoid anal discharge, and fever. During hospitalization, with provision of supportive care, an area of necrotizing fasciitis around the prepuce and anus developed and surgical debridement was performed. Severe sepsis developed secondary to the necrotizing fasciitis and the cat was eventually euthanized.
New Information Provided – The purpose of this report is to document the first case of Fournier's gangrene in a cat that presented for mucoid anal discharge, lethargy, and mild ataxia, and to alert emergency clinicians to this disease process. Early detection of the disease with prompt, aggressive supportive care and surgical debridement is necessary for successful treatment.     

Successful treatment of necrotizing fasciitis in the hind limb of a great dane

A 5-month-old, intact female Great Dane was presented for an acute onset of rapidly progressive lameness, severe pain, and diffuse swelling of the right hind limb. Ultrasound evaluation revealed echogenic fluid pockets extending along fascial planes of the right hind limb, from the proximal femur to the hock. Necrotic soft tissues were debrided, and closed-suction drains were placed. No foreign material was identified at surgery. Fluid culture identified a beta-hemolytic Streptococcus sp., and affected fascial histopathology was consistent with necrotizing fasciitis. Postoperatively, the puppy was managed with intravenous broad-spectrum antibiotics, local infusions of amikacin, and daily physical rehabilitation. Oral pentoxifylline was administered to treat bronchopneumonia and streptococcal toxic shock syndrome that developed secondary to necrotizing fasciitis. To our knowledge, this is the first report of a successfully managed case of beta-hemolytic, streptococcal, necrotizing fasciitis successfully managed after a single surgical debridement in combination with systemic broad-spectrum antibiotics, local amikacin infusion, active closed-suction drainage, daily cytology, massage, and passive range-of-motion exercises to maintain limb function.     

Necrotizing fasciitis: a review

Necrotizing fasciitis is a rapidly spreading, bacterial, soft-tissue infection reported in both humans and dogs. A review of the pathophysiology, clinical findings, diagnosis, and treatment of necrotizing fasciitis is presented, with the goal of familiarizing veterinarians with this uncommon but potentially fatal condition. A case report highlighting the fulminant course of this disease is also included.     

Splenocaval Shunting for Alleviation of Portal Hypertension in a Dog: A Case Report

Objective —To describe the construction and use of a splenocaval shunt to prevent portal hypertension in a dog with iatrogenic rupture and subsequent complete occlusion of an intrahepatic portosystemic shunt (IPSS).
Study Design —Case report describing a single, client-owned animal.
Results —During dissection, the back wall of an IPSS was torn. Complete shunt occlusion was required to control the hemorrhage. This resulted in the development of life-threatening portal hypertension. Emergency splenocaval shunt construction reduced the portal pressure from 47 to 20 cm H₂0. The dog experienced minimal postoperative complications. A second surgical procedure was performed a month later to completely ligate the splenocaval shunt.
Conclusions —A splenocaval shunt can be used to divert blood from the portal to the systemic circulation to control portal hypertension. In this dog, it resulted in a successful outcome with few complications.
Clinical Relevance —The splenocaval shunt could be constructed before the dissection of a difficult IPSS if problems arise as occurred in the dog described in this report. Complete IPSS occlusion can be performed without development of portal hypertension.     

Staphylococcus pseudintermedius necrotizing fasciitis in a dog

Staphylococcus pseudintermedius was implicated as the cause of rapidly progressive and fatal necrotizing fasciitis in a dog. The isolate was methicillin-susceptible and did not contain genes encoding the Panton-Valentine leukocidin. While Streptococcus canis is typically considered to be the main cause of necrotizing fasciitis in dogs, staphylococci should also be considered.     

Surgical treatment of lumbosacral foraminal stenosis using a lateral approach in twenty dogs with degenerative lumbosacral stenosis

Objectives— To describe clinical signs, magnetic resonance imaging (MRI) and surgical findings using a lateral approach to the lumbosacral intervertebral foramen and to evaluate clinical outcomes in dogs with or without concurrent dorsal decompression and annulectomy.
Study Design— Retrospective study.
Animals— Dogs (n=20) with degenerative lumbosacral stenosis (DLSS).
Methods— Medical records (2002–2006) of dogs that had lumbosacral lateral foraminotomy alone or in combination with dorsal decompression were reviewed. Degree of dysfunction was assessed separately for each pelvic limb; dogs with unilateral signs were included in group A, those with bilateral signs in group B. Retrieved data were: signalment, history, neurologic status on admission, 3 days, 6 weeks, and 6 months postoperatively, duration of clinical signs, results of MRI, surgical site(s), intraoperative findings, and outcome.
Results— Based on the clinical and MRI findings unilateral foraminotomy was performed in 8 dogs, bilateral foraminotomy in 1 dog, unilateral foraminotomy with concurrent dorsal decompression in 7 dogs, and bilateral foraminotomy with concomitant dorsal decompression in 4 dogs. Surgery confirmed the presence of foraminal stenosis in all dogs, with osteophyte formation and soft tissue proliferations being the most common lesions. Outcome was good to excellent in 19 dogs and poor in 1 dog. Mean follow-up was 15.2 months (range, 6–42 months).
Conclusion— Lateral foraminotomy addresses compressive lesions within exit and middle zones of the lumbosacral foramen.
Clinical Relevance— Successful surgical management of DLSS is dependent on recognition and correction of each of the compressive lesions within the lumbosacral junction.     

Generalized nodular dermatofibrosis and renal cystadenocarcinomas in a German shepherd dog

Generalized, nodular dermatofibrosis with coexisting bilateral renal cystadenocarcinomas was diagnosed in a 6-year-old male German Shepherd Dog. Approximately 3 years earlier, the dog had been examined because of lameness attributable to 2 nodular growths between the third and fourth digits of the right front limb. Biopsy revealed dense collagenous dermal fibrosis, often in a nodular arrangement. As the disease progressed, attempts to alleviate the discomfort and lameness caused by the nodular growths were performed by surgical excision. During this period, other nodular growths that developed apparently did not bother the dog. Because of the long and protracted clinical progression of the disease and poor prognosis for successful treatment, the dog was euthanatized. At necropsy, multiple multicentric nodules were found in the skin and subcutis, with most located on the limbs. The nodules were well-circumscribed and hard. Epithelial ulceration and inflammation were confined to nodules on the feet. Small foci of collagenous proliferation were found along fascial planes. In addition, cystic neoplasms were in both kidneys. The microscopic diagnosis was generalized nodular dermatofibrosis, with bilateral renal cystadenocarcinomas.     

Intestinal Entrapment and Strangulation Caused by Rupture of the Duodenocolic Ligament in Four Dogs

Objective — The purpose of this study was to describe four dogs with intestinal entrapment and strangulation caused by a rupture of the duodenocolic ligament.
Study Design — This case series documents historical findings, physical examination findings, diagnostic workup, surgical intervention, and outcome of four dogs confirmed at surgery with duodenocolic ligament rupture.
Results — Three of four dogs were German shepherds, and two of three German shepherds were intact males. The history, clinical signs, and physical examination findings were not specific for intestinal entrapment. The clinical signs in three of four dogs included chronic vomiting, diarrhea, anorexia, and lethargy. In the remaining dog, the clinical signs were vomiting and peracute collapse. This dog rapidly deteriorated over a few hours because of strangulation of the entrapped intestines. In two of four dogs, abdominal radiographs showed a distended colon displaced to the right side of the abdominal cavity. Surgery involved transection of the remaining ventral remnant of the duodenocolic ligament and replacing the colon into its normal anatomic position. The three dogs with chronic clinical signs were either still alive, or were euthanatized for unrelated problems. The dog with strangulation of the entrapped intestines was euthanatized at the time of surgery.
Conclusions and Clinical Relevance — Duodenocolic ligament rupture with secondary bowel entrapment can occur in dogs. The prognosis for these animals is favorable provided there is no vascular compromise of the entrapped bowel segments. The peracute history, progression of the disease process, and outcome of the fourth dog in this study indicate that surgery should be performed as an emergency procedure.     

Cervical Spinal Locking Plate in Combination with Cortical Ring Allograft for a One Level Fusion in Dogs with Cervical Spondylotic Myelopathy

Objective— To evaluate use of a surgical technique commonly used in humans for treatment of cervical spondylotic myelopathy (CSM) in dogs.
Design— Prospective case series.
Animals— Dogs with CSM (n=10).
Methods— Dogs weighing >30 kg that had CSM at 1 vertebral articulation were eligible for inclusion. Dogs had vertebral column distraction/fusion performed using a cortical ring allograft, cancellous autograft, and a spinal locking plate. Dogs were evaluated temporally by repeat neurological examinations and by client perception of postsurgical outcome, determined by telephone interview.
Results— Nine dogs survived the immediate postoperative period. Seven of 8 dogs had moderate to complete improvement without recurrence (mean follow-up, 2.48 years). The most common postsurgical complications were screw loosening (n=4) and plate shifting (2), neither of which required surgical revision. One dog had pseudoarthrosis that may have negatively impacted outcome.
Conclusion— Treatment of single level CSM in dogs with ring allograft and a spinal locking plate system may lead to successful outcomes. The major problems encountered with included cost of the implants and adjusting the system designed for humans to fit the vertebral column of a dog.
Clinical Relevance— For dogs with CSM at a single level, the use of a spinal locking plate in combination with a cortical ring allograft can be an effective surgical treatment. Costs of the implants as well as anatomic differences in dogs make this type of surgery less appealing.     

A technique for resection of invasive tumors involving the trigone area of the bladder in dogs: preliminary results in two dogs

Objective— To describe a surgical technique for resection of the entire bladder neck, including the trigone and proximal urethra in dogs with invasive tumors causing life-threatening urinary tract obstruction.
Study Design— Clinical case reports.
Animals— Dogs (n=2) with bladder tumors.
Methods— Circumferential excision of the bladder neck and proximal urethra with preservation of the neurovascular pedicles was performed to remove a rhabdomyosarcoma (dog 1) and a transitional cell carcinoma (dog 2) involving the trigone and bladder neck that were causing urinary tract obstruction. Reconstruction of the bladder and proximal urethra included bilateral ureteroneocystostomy. Adjuvant chemotherapy was administered postoperatively to both dogs.
Results— Postoperatively, dogs 1 and 2 were continent after 7 and 17 days, respectively, and regained normal urinary function after resolution of a transient pollakiuria. Dog 1 had no evidence of local or regional recurrence; however, a large solitary pulmonary metastatic lesion was diagnosed 8 months later. The dog was euthanatized despite a lack of clinical signs. Dog 2 had at least 1 metastatic lesion in the abdominal wall 6 months later and was euthanatized at 580 days because of renal failure.
Conclusion— En-bloc removal of the bladder neck and proximal urethra with preservation of the dorsal vascular and nervous pedicles, although a technically challenging procedure, can be performed without associated urinary incontinence or bladder wall necrosis.
Clinical Relevance— In dogs with invasive bladder tumors causing life-threatening urinary tract obstruction, resection of the bladder neck and proximal urethra should be considered as a promising surgical alternative to urinary diversion.     

Pericardial effusion and cardiac tamponade caused by intrapericardial granulation tissue in a dog

Objective – To describe and report successful surgical management of pericardial effusion and cardiac tamponade in a dog caused by intrapericardial granulation tissue.
Case Summary – An 8-month-old, intact male, Greater Swiss Mountain Dog was referred for cardiac evaluation following 2 weeks of progressive lethargy, abdominal distention, and difficulty breathing. On the day of presentation, the dog had an episode of acute collapse. A 14-cm multilocular pericardial cystic lesion causing collapse of the right atrial free wall and resulting in pericardial tamponade was observed on echocardiogram. After the dog subsequently experienced two acute episodes of pericardial effusion, a subtotal pericardectomy was performed and clinical signs resolved. The histopathologic diagnosis of the mass was inflammation and granulation tissue, likely caused by a resolving hematoma or abscess.
New or Unique Information Provided – This is the first report of intrapericardial granulation tissue as the cause of pericardial effusion and cardiac tamponade.     

Relatedness of Streptococcus canis from canine streptococcal toxic shock syndrome and necrotizing fasciitis.

The emergence of streptococcal toxic shock syndrome (STSS) and necrotizing fasciitis (NF) in dogs caused by Streptococcus canis has been reported by our laboratory. Since clonal expansion is thought to be partially responsible for the spread of invasive strains of Streptococcus pyogenes in humans, the relatedness of 15 isolates of S. canis from canine STSS and/or NF was examined using pulsed field gel electrophoresis and biotyping; production of proteases and of a CAMP-like reaction were also examined. Only 2 of the 15 STSS and/or NF isolates were clonally related, suggesting that the emergence of canine STSS/NF is not the result of clonal expansion of one or more highly virulent strains of S. canis. All of the isolates produced proteases and demonstrated a CAMP-like reaction, which appear to be additional characteristics of S. canis.     

Longitudinal bone transport for treatment of primary bone tumors in dogs: technique description and outcome in 9 dogs

OBJECTIVE: To describe a surgical technique for bone transport osteogenesis (BTO) limb salvage and report outcome in 9 dogs with primary bone tumors. ANIMALS: Nine dogs with spontaneously occurring primary bone tumors. RESULTS: BTO surgery was performed as a primary means of limb salvage in 7 dogs and as a salvage procedure after catastrophic allograft infection and failure in 2 dogs. Mean defect size was 9.5 cm with a mean of 123 days distraction until docking. Mean time from surgery to fixator removal was 205 days. Minimum follow-up was 9 months. There were 2 histologically confirmed local recurrences where although limb function was excellent, eventually resulted in limb amputation. Limb function was good to excellent in all but 2 dogs; 1 was chronically non-weight bearing before BTO surgery because of complications associated with an allograft limb salvage that had been performed previously on the same limb. The cause of lameness in the other dog was undetermined. CONCLUSIONS: BTO limb salvage can be successful in dogs with primary bone tumors. Whereas allograft limb salvage may be simpler from an initial management perspective, BTO has some unique advantages when compared with the allograft technique. CLINICAL RELEVANCE:BTO has an emerging role in limb salvage surgery for dogs with primary bone tumors. BTO provides excellent long-term outcomes in some dogs with primary bone tumors and will likely become increasingly more attractive as technique modifications allow the duration of the treatment to be shortened.     

Characteristics and outcomes in surgical management of severe acute pancreatitis: 37 dogs (2001–2007)

Objective – Describe clinical characteristics and outcomes associated with canine patients undergoing surgical intervention for treatment of acute pancreatitis.
Design – Retrospective outcome study from 2001 to 2007.
Animals – Thirty-seven dogs.
Interventions – None.
Measurements and Main Results – The following data were collected for dogs who underwent surgical intervention in the course of treatment for severe acute pancreatitis: preoperative clinicopathologic and physical data, ultrasonographic findings, surgical procedure detail, histopathologic findings, and transfusion requirements. The survival rate was 80.8% in dogs with extrahepatic biliary obstruction, 64.3% in dogs undergoing necrosectomy, and 40.6% with pancreatic abscess. Overall survival was 63.6%. Surgical complications included intraoperative and postoperative hemorrhage in 12 dogs, postoperative development of diabetes mellitus in 3 dogs, exocrine pancreatic insufficiency in 1 dog, and bacterial peritonitis in 2 dogs.
Conclusion – Surgical intervention and aggressive postoperative care may be pursued in select dogs with severe acute pancreatitis. In dogs with extrahepatic biliary obstruction secondary to acute pancreatitis, surgical intervention may be associated with a good prognosis whereas dogs with pancreatic abscess formation may have a more guarded prognosis.     

Intraoperative radiation for limb sparing of the distal aspect of the radius without transcarpal plating in five dogs

Objectives— To evaluate intraoperative irradiation (IORT) as a method of limb spare with preservation of the radiocarpal joint.
Study Design— Prospective case series.
Animals— Dogs (n=5) with stage II sarcoma of the distal aspect of the radius.
Methods— A bone segment containing the tumor was isolated surgically, treated by IORT, reimplanted, and secured by internal fixation. In 1 dog, the postradiation tumor bed was curetted and filled with bone cement. Dogs were administered alternating adriamycin and carboplatin starting 2 weeks after IORT and monitored at regular intervals.
Results— Four dogs had osteosarcoma and 1 had undifferentiated sarcoma. Implant failure (n=3), deep tissue infection (3), and pathologic fracture (3) resulted in amputation (3) or pancarpal plating (2). The dog with undifferentiated sarcoma was euthanatized because of suspected tumor recurrence 4 months postoperatively. Osteotomy healing was documented by radiography (1), histopathology (2), or by direct observation (2).
Conclusions— A technique for limb-sparing surgery of the distal portion of the radius in dogs using IORT had advantages include healing of the autograft and a source for a perfectly fitting autograft but did not appear to offer any advantage with respect to infection rate. Long-term preservation of the radiocarpal joint was not successful.
Clinical Relevance— It was not possible to preserve the function of the radiocarpal joint and so this technique cannot be recommended currently. Further study is needed to evaluate whether or not IORT can be considered in combination with pancarpal plating and possibly curettage and cementation of the tumor to prevent subchondral bone collapse.     

Babesiosis Caused by a Large Babesia Species in 7 Immunocompromised Dogs

Background: A large unnamed Babesia species was detected in a dog with lymphoma. It was unknown if this was an underrecognized pathogen.
Objective: Report the historical and clinicopathologic findings in 7 dogs with babesiosis caused by a large unnamed Babesia species characterize the 18S ribosomal ribonucleic acid (rRNA) genes.
Animals: Seven immunocompromised dogs from which the Babesia was isolated.
Methods: Retrospective case review. Cases were identified by a diagnostic laboratory, the attending clinicians were contacted and the medical records were reviewed. The Babesia sp. 18S rRNA genes were amplified and sequenced.
Results: Six of 7 dogs had been splenectomized; the remaining dog was receiving oncolytic drugs. Lethargy, anorexia, fever, and pigmenturia were reported in 6/7, 6/7, 4/7, and 3/7 dogs. Laboratory findings included mild anemia (7/7) and severe thrombocytopenia (6/7). Polymerase chain reaction (PCR) assays used to detect Babesia sensu stricto species were all positive, but specific PCR assays for Babesia canis and Babesia gibsoni were negative in all dogs. The 18S rRNA gene sequences were determined to be identical to a large unnamed Babesia sp. previously isolated. Cross-reactive antibodies against other Babesia spp. were not always detectable. Five dogs were treated with imidocarb dipropionate and 1 dog with atovaquone/azithromycin; some favorable responses were noted. The remaining dog was untreated and remained a clinically stable carrier.
Conclusions and Clinical Importance: Dogs with pigmenturia, anemia, and thrombocytopenia should be tested for Babesia sp. by PCR. Serology is not sufficient for diagnosis of this Babesia sp. Asplenia, chemotherapy, or both might represent risk factors for persistent infection, illness, or both.     

Suspected lily-of-the-valley (Convallaria majalis) toxicosis in a dog

Objective: To describe successful treatment of third-degree atrioventricular (AV) block using temporary noninvasive transthoracic pacing and placement of a permanent transvenous pacemaker in a case of suspected lily-of-the-valley ( Convallaria majalis ) intoxication in a dog.
Case summary: A 2-year-old neutered male Beagle weighing 17.8 kg was presented to the emergency service for treatment of bradycardia, vomiting, and lethargy. An electrocardiogram revealed third-degree AV block that was nonresponsive to atropine. Ten hours after admission, the dog became obtunded. Treatment initially consisted of temporary noninvasive transthoracic pacing and eventually placement of a permanent transvenous pacemaker. The initial history did not suggest that the dog had access to any known cardiotoxins. However, C. majalis , which contains cardiac glycosides, was identified within the dog's environment and the dog's serum did contain digoxin or an immunologically cross-reactive compound.
New or unique information provided: This is the first reported successful management of C. majalis toxicosis in a dog. Temporary noninvasive transthoracic pacing was used in the management of this case as a safe and effective bridge to permanent pacemaker implantation.