JAAHA 57.1 Abstracts

RETROSPECTIVE STUDIES

Combination of Prednisolone and Azathioprine for Steroid-Responsive Meningitis-Arteritis Treatment in Dogs

Lucile Giraud, Maud Girod, Laurent Cauzinille

Treatment with high corticosteroid dosages for steroid-responsive meningitis-arteritis (SRMA) is correlated with severe adverse effects and worse quality of life. In order to improve immunosuppression and decrease dosage and duration of glucocorticoid treatment, a second immunosuppressive drug is commonly used in most of the immune-mediated diseases. The objective of this retrospective study was to evaluate the efficacy, tolerability, and occurrence of relapse for the combination of prednisolone and azathioprine. All dogs received azathioprine 2 mg/kg q 24 hr for 1 mo and then 2 mg/kg every other day for 2 mo; prednisolone was started at an immunosuppressive dosage and tapered off gradually during a mean of 3 mo. Twenty-six dogs met inclusion criteria. Twenty-one dogs (81%) were in clinical remission with no relapse observed within the 2 yr follow-up period. Treatment was well tolerated in all dogs and side effects were most of the time mild and self-limiting. The relapse rate (19%) was lower than most published rates. A prednisolone and azathioprine combination appeared to be effective for primary treatment of dogs with SRMA and allows a quicker tapering in prednisolone dosage, a decrease in long-term side effects of steroids, a shorter duration of treatment, and a low relapse rate. Read the full article

RETROSPECTIVE STUDIES

Gastric Physaloptera Infection in 27 Dogs (1997–2019)

Leah Soderman, Kenneth R. Harkin

Infection with the stomach worm Physaloptera spp. in dogs can cause chronic vomiting, although the diagnosis is often difficult owing to a low worm burden, single-sex infections, a failure to produce ova, or ova that are of greater density than solutions routinely used for qualitative fecal flotation. A retrospective evaluation was performed of 27 dogs that had gastric Physaloptera spp. infection confirmed endoscopically. In 23 of 27 dogs (85.2%), chronic vomiting was the chief complaint, and Physaloptera was an incidental finding in 3 dogs with esophageal or gastric foreign bodies. The worm burden was low (1–3 worms) in 21 dogs (77.8%), but 2 dogs were infected with large numbers (>50 worms). Prior therapy with routine doses of anthelmintics was ineffective in eight dogs prior to endoscopy. A higher dose and longer duration of fenbendazole in combination with pyrantel pamoate is recommended for treatment of suspected or confirmed infections. Reinfection is common in some dogs and should not be viewed as treatment failure. Read the full article

RETROSPECTIVE STUDIES

Approach to the Diagnosis of Hepatocutaneous Syndrome in Dogs: A Retrospective Study and Literature Review

Karah Burns DeMarle, Cynthia R. L. Webster, Dominique Penninck, Lluis FerrerKarah Burns DeMarle, Cynthia R. L. Webster, Dominique Penninck, Lluis Ferrer

Superficial necrolytic dermatitis (SND) is a rare and often fatal disease in dogs that has been associated with pancreatic neuroendocrine neoplasia (SND/EN) and hepatocutaneous syndrome (SND/HCS). Although various combinations of diagnostics have been used to differentiate these two causes of SND, there are currently no data on which combination would enable the most timely and noninvasive way to diagnose HCS. Medical records were reviewed retrospectively (2004–2018) for dogs with SND/HCS (n = 24) and SND/EN (n = 1). These data were compared with cases found by review of the literature of dogs with SND/HCS (n = 105) and SND/EN (n = 13). The most consistent findings with SND were dermatological lesions affecting paw pads or mucocutaneous junctions (143/143, 100%) and marked plasma hypoaminoacidemia (58/58, 100%). On ultrasound, a honeycomb liver was seen in 62/63 (98%) dogs with SND/HCS but none with SND/EN. Six out of 23 (26%) dogs in the retrospective study with SND/HCS had marked keratinocyte apoptosis, a finding that was associated with diabetes mellitus. This study suggests that in dogs with characteristic skin lesions, an amino acid profile permits a noninvasive diagnosis of SND. An abdominal ultrasound can then assist in the differentiation of SND/HCS and SND/EN. Read the full article

CASE SERIES

Dorsal Atlantoaxial Ligament Hypertrophy as a Cause for Clinical Signs in Dogs with Dens Abnormalities

Ana Cloquell, Rocio Orlandi, Fernando Vázquez, Isidro Mateo

The objective of this study is to suggest clinical and subclinical atlantoaxial (AA) instability as a cause for dorsal AA ligament hypertrophy responsible for clinical signs in dogs with dens abnormalities. Clinical information from five dogs with malformed dens and dorsal spinal cord compression at the AA junction was collected. All dogs had neck pain, associated with tetraparesis in three cases. Radiological examination revealed hypoplastic dens in two dogs and a defect in its ossification in the other three. Stress views were able to demonstrate obvious AA instability only in two cases, but it was suspected in the other owing to response to surgical fixation of the joint and the presence of a dorsal compressive band, which was considered an enlarged dorsal AA ligament. Surgical and histopathological examination of compressive tissue confirmed hypertrophy of the ligament. Long-term prognosis in the four operated cases, either by dorsal decompression and ventral fixation or by ventral fixation alone, was excellent. A malformed dens can cause subclinical instability, unnoted in dynamic studies. As instability may lead to hypertrophy of joint ligaments, soft tissue changes (specifically dorsal AA ligament hypertrophy) points out this instability and the need for joint fixation if surgical management is required. Read the full article

CASE REPORTS

Use of a Bipolar Vessel-Sealing Device for Splenic Parenchymal Resection in Three Dogs and One Cat

Heather Siemon

Based on splenic abnormalities noted during surgery, four client-owned animals (three dogs, one cat) undergoing exploratory laparotomy were identified as candidates for partial splenectomy. In three cases, small mass lesions of the spleen were identified on elective exploratory laparotomy. In one case, the patient was referred for emergency surgery for diaphragmatic hernia with entrapment of stomach and spleen. The discovery of avulsion of a significant portion of the splenic mesentery led to the decision to perform partial splenectomy in this case. All animals included in the study underwent partial splenectomy by one of two board-certified veterinary surgeons at a multispecialty hospital between 2014 and 2018. The same type of bipolar vessel-sealing device was used in each surgery, and three of four partial splenectomy cases recovered uneventfully. One patient went into cardiopulmonary arrest hours after surgery and died; however, this is not suspected to be due to the described partial splenectomy technique. The bipolar vessel-sealing device is suitable for use in resection of the splenic parenchyma in some canine and feline patients. This technique is designed to decrease surgical time, provide effective hemostasis, and preserve the important functions of the spleen that are lost when total splenectomy is undertaken. Read the full article

CASE REPORTS

Long-Term Outcome After Surgical Resection of a Spinal Choroid Plexus Tumor in a Dog

Yuya Saitoh, Takeshi Aikawa, Yuta Miyazaki, Masaaki Nishimura

A 6 yr old castrated male Clumber spaniel was referred for evaluation of acute paraplegia. MRI of the thoracolumbar spine demonstrated an intradural-extramedullary mass lesion at the level of T12 and extradural spinal cord compression at L1-L2. A hemilaminectomy was performed to achieve gross total resection of the mass lesion and removal of extruded disc material. A diagnosis of spinal choroid plexus tumor (CPT) and intervertebral disc extrusion was made. At 4 mo postoperatively, MRI demonstrated a mass lesion at the right lateral aperture of the fourth ventricle. Spinal drop metastasis from a primary intracranial CPT was suspected. The dog was ambulating independently and neurologically normal at that time. At 17 mo postoperatively, a third MRI was performed owing to decreased postural reactions in both hind limbs and vision loss in the right eye, and it demonstrated an increase in size of the intracranial mass lesion. These two additional MRI studies of the entire central nervous system showed no other metastatic lesions nor any evidence of local recurrence. At 25 mo postoperatively, the dog died at home. This is the first case report of surgical intervention and antemortem histopathological diagnosis of a spinal CPT in a dog. Read the full article

CASE REPORTS

First Documented Cases of Canine Neuroangiostrongyliasis Due to Angiostrongylus cantonensis in Hawaii

Jenee Odani, Erika Sox, Will Coleman, Rajesh Jha, Richard Malik

Two young dogs domiciled in Honolulu, Hawaii, were presented in November and December 2018 (respectively) for spinal hyperesthesia, hindlimb weakness, and proprioceptive ataxia. Both dogs had neurologic findings referable to spinal cord disease. Both dogs had a combination of lower motor neuron signs (reduced muscle mass, decreased withdrawal reflexes, low tail carriage) and long tract signs (conscious proprioceptive deficits, crossed extensor response, increased myotatic reflexes). Peripheral eosinophilia was present in the second case, but hematology and serum biochemistries were otherwise unremarkable. Plain radiographs and computed tomography scans ± contrast were unremarkable. Cerebrospinal fluid (CSF) from both patients demonstrated eosinophilic pleocytosis, and real-time polymerase chain reaction testing demonstrated Angiostrongylus cantonensis deoxyribonucleic acid in CSF, confirming a diagnosis of neuroangiostrongyliasis. Treatment included glucocorticoid therapy, ± anthelmintic (fenbendazole). Both dogs made a complete recovery. These are the first confirmed cases of autochthonous neuroangiostrongyliasis in canine patients in the United States and the first dogs anywhere to be diagnosed definitively with A. cantonensis infection based on real-time polymerase chain reaction testing of CSF. A clinician examining a patient with severe spinal hyperesthesia and a combination of upper and lower motor signs should consider A. cantonensis as a differential, especially in endemic areas. Read the full article

CASE REPORTS

Acute Hepatopathy in a Dog Secondary to Hypothyroidism-Induced Atherosclerotic Infarction and Necrosis

Timothy Andrew Bolton

A 7 yr old male beagle was examined because of lethargy, anorexia, and cranial abdominal discomfort. Significant clinicopathologic abnormalities included severe liver enzyme elevations and hypercholesterolemia. Abdominal imaging identified vascular compromise of the left lateral liver lobe and a gallbladder mucocele. Following liver lobectomy and cholecystectomy, the dog’s clinical signs resolved, and liver enzymes substantially improved. Diffuse hepatocellular infarction and necrosis secondary to multifocal atherosclerosis was present on histopathology of the liver. Hypothyroidism was subsequently diagnosed. Restoration of euthyroidism with oral levothyroxine therapy resolved the remaining liver enzyme elevations and hypercholesterolemia. To the author’s knowledge, this is the first case report of hypothyroidism resulting in a clinically apparent and resolvable acute hepatopathy due to atherosclerosis. Clinicians should include atherosclerosis as a differential diagnosis for dogs with an acute hepatopathy and investigate dogs for hypothyroidism if atherosclerosis is diagnosed on liver biopsy. Read the full article