Nodular dermatofibrosis and cystic renal disease in three mixed-breed dogs and a Boxer dog

Three mixed-breed dogs and a Boxer dog with nodular dermatofibrosis are described. The three mixed breed dogs had concurrent renal epithelial cysts ( n  = 2) or renal cystadenomas ( n  = 1); these lesions were visualized antemortem on ultrasonographic examination. One of these dogs was a 7-year-old Labrador Retriever-Gordon Setter mixed breed which survived 5 years after diagnosis, and was euthanized for unrelated causes. The Boxer dog had renal cystic adenomatous hyperplasia and renal cystadenocarcinomas which were not visualized on ultrasonographic examination but were diagnosed at necropsy.     

Hereditary multifocal renal cystadeno-carcinomas and nodular dermatofibrosis in 51 German sheoherd does

The clinical findings In German shepherd dogs with hereditary multifocal renal cystadenocarcinomas and nodular dermatofibrosis are presented. Between 1978 and 1996, 51 cases were examined. Eight cases were detected after being offered a clinical examination because the disease was present in a parent. The remaining 43 dogs were diagnosed after an unsolicited visit to a clinic because of a specific problem. Skin lesions were the main reason (37 per cent) the owners presented their dog for examination. The mean age at diagnosis of renal cystadenocarcinomas and nodular dermatofibrosis was 8-2 years. The male-to-female ratio was 1-1, while the corresponding figure for a reference population was 1–25. Enlarged and abnormally shaped kidneys were palpated In 60 per cent of the dogs and were detected by radiography in 86 per cent of cases. The renal lesions, including metastases, were the main reason for euthanasia and death. The mean age at death was 9-3 years, and the mean age at the first detection of nodular dermatofibrosis was 6-4 years.     

MAGNETIC RESONANCE IMAGING AND COMPUTED TOMOGRAPHY CHARACTERISTICS OF INTRACRANIAL INTRA-ARACHNOID CYSTS IN 6 DOGS

Magnetic resonance imaging (MRI) and computed tomographic imaging (CT) characteristics of intracranial intra-arachnoid cysts in six dogs are described.Of the six dogs, three were less than one year of age and 4 were males. Five of the six dogs weighed less than 11 kg. Five cysts were located in the quadrigeminal cistern.On CT images, the intracranial intra-arachnoid cysts had sharply defined margins, contained fluid isodense to CSf and did not enhance following IV administration of contrast. On MRI images, the intracranial intra-arachnoid cysts were extra-axial, contained fluid isointense with CSF and did not enhance following IV contrast. While spinal arachnoid cysts of dogs have been reported in the literature, other than the six dogs contained in this report, intracranial intra-arachnoid cysts have not to our knowledge been described in animals. These six dogs have a similar age, sex, arachnoid cysts.     

Polycystic kidney disease in bull terriers: an autosomal dominant inherited disorder

The prevalence, mode of inheritance and urinalysis findings in Bull Terriers with polycystic kidney disease were assessed by screening 150 clinically normal dogs. The disorder was diagnosed in 39 dogs on the basis of renal ultrasound results and family history of the disease. In equivocal cases confirmation required gross and histopathological renal examination. Necropsy was performed on nine affected dogs and the kidneys from another five affected animals were also examined. Renal cysts were usually bilateral, occurred in cortex and medulla and varied from less than 1 mm to over 2.5 cm in diameter. Cysts were lined by epithelial cells of nephron origin. Abnormal urine sediment and proteinuria were common in affected dogs. The disease appears to be inherited in a highly penetrant autosomal dominant manner.     

Bilateral multiple cystic kidney disease and renal cortical abscess in a Boerboel

Cystic renal disease is rare in dogs and although infected renal cysts have been reported in humans, no report could be found in dogs. A 58 kg, 5-year-old, castrated, male Boerboel presented with weight loss, pyrexia, lethargy and vomiting, 20 months after an incident of haematuria was reported. The initial ultrasonographic diagnosis was bilateral multiple renal cysts of unknown aetiology. The cysts had significantly increased in size over the 20-month period and some contained echogenic specks which could be related to infection, normal cellular debris or haemorrhage. In both kidneys the renal contours were distorted (the left more than the right). The abnormal shape of the left kidney was largely due to multiple cysts and a large crescent-shaped septate mass on the cranial pole of the kidney. Aspirates of the septate mass were performed (left kidney) and the cytology and culture were indicative of an abscess. It is suggested that the previous incident of haematuria provided a portal of entry for bacteria into the cysts resulting in renal cortical abscess formation.     

Generalized nodular dermatofibrosis in the absence of renal neoplasia in an Australian Cattle Dog

A 13-year-old, spayed, female Australian Cattle Dog had at least a 10-year history of numerous subcutaneous nodules for which fine-needle aspiration and cytologic evaluation were nondiagnostic. Abdominal ultrasound 3.5 months before necropsy detected a small left kidney but no cysts or neoplasms. At gross necropsy, innumerable, firm, round to oval, white, 0.25 to 2 cm masses were detected throughout the subcutaneous tissues of the axial and appendicular skeleton, epimysium of numerous muscles, and parietal peritoneum of the lateral abdominal body wall. The left kidney was approximately half the size of the right, and there was severe bilateral renal medullary (papillary) necrosis. Histologically, the subcutaneous nodules were well-demarcated masses of mature, hypocellular collagen that were consistent with previous reports of nodular dermatofibrosis and renal cystadenomas or cystadenocarcinomas. In addition to diffuse acute medullary necrosis, both kidneys were affected by severe chronic lymphoplasmacytic interstitial nephritis. This is the first known report of nodular dermatofibrosis in a dog without renal cysts, cystadenoma, or cystadenocarcinoma.     

Ultrasound-assisted drainage and alcoholization of hepatic and renal cysts: 22 cases

Twenty-two dogs and cats with symptomatic renal or hepatic cysts that had undergone ultrasound-assisted drainage and alcoholization were retrospectively evaluated. Common presenting complaints were anorexia, reluctance to move, and vomiting. Abdominal pain was observed in all cases. Systemic hypertension was identified in four dogs and four cats with renal cysts. Cyst drainage and alcoholization were achieved without complications in 19 animals, and all clinical signs resolved after the procedure. In three cases, transient bleeding was observed during alcoholization, and the procedure was interrupted. Blood pressure normalized in the four dogs with renal cysts, but it remained elevated in the four cats.     

Cervical Myelopathy Associated with Extradural Synovial Cysts in 4 Dogs

Three Mastiffs and 1 Great Dane were presented to the University of Wisconsin Veterinary Medical Teaching Hospital for cervical myelopathy based on history and neurologic examination. All dogs were males and had progressive ataxia and tetraparesis. Degenerative arthritis of the articular facet joints was noted on survey spinal radiographs. Myelography disclosed lateral axial compression of the cervical spinal cord medial to the articular facets. Extradural compressive cystic structures adjacent to articular facets were identified on magnetic resonance imaging (1 dog). High protein concentration was the most important finding on cerebrospinal fluid analysis. Dorsal laminectomies were performed in all dogs for spinal cord decompression and cyst removal. Findings on cytologic examination of the cystic fluid were consistent with synovial fluid, and histopathologic results supported the diagnosis of synovial cysts. All dogs are ambulatory and 3 are asymptomatic after surgery with a follow-up time ranging from 1 to 8 months. This is the 1st report of extradural synovial cysts in dogs, and synovial cysts should be a differential diagnosis for young giant breed dogs with cervical myelopathy.     

Comparison of excretory urographic contrast effects of dimeric and monomeric non-ionic iodinated contrast media in dogs

In excretory urography, the osmolarity of contrast media has rarely been treated as important in veterinary medicine. In this study, the contrast effect of two contrast media (monomeric iohexol and dimeric iodixanol) in the renal cortex and aorta were compared using computed tomography (CT). Five beagle dogs were used and the study employed a cross-over method for each contrast media. The results showed that there was no difference between the media in the aorta, but iodixanol showed higher CT value and a longer contrast effect than iohexol in the renal cortex, in spite of having the same iodine dosage. It is believed that iodixanol, with its low osmolarity, is diluted less by osmotic diuresis than monomeric iohexol. It is important to consider the osmolarity of the contrast media when evaluating the contrast effect, and it is essential to use the same contrast media for each examination, or the renal excretory speed will be under/overestimated.     

Ultrasonography of the parathyroid glands in dogs--a review

The purpose of the study was to give an overview over the usefulness of ultrasonographic examination of parathyroid glands in dogs. By means of a 10 MHz high-resolution linear transducer it was possible to visualize parathyroid glands in healthy dogs. There was a positive correlation between body weight and size of the parathyroid glands, additionally the likelihood to detect 4 glands increased with an increase in body weight. Dogs with chronic renal failure had significantly larger parathyroid glands than healthy dogs and dogs with acute renal failure. In dogs with hypercalcemia of malignancy either none or parathyroids which were small in relation to body weight were detected. In contrast visualisation of parathyroid masses in dogs with primary hyperparathyroidism was easy due to their increased size and anechoic appearance. In dogs with severe azotemia the ultrasonographic examination of the parathyroid glands is helpful to differentiate between acute and chronic renal failure, in dogs with hypercalcemia to differentiate between hypercalcemia of malignancy and hypercalcemia due to primary hyperparathyroidism.     

Renal dysplasia in boxers and Finnish harriers

Puppies from two litters of dogs were found to have severe polyuria and polydipsia. Four of the dogs were investigated by means of clinical examination, haematological and biochemical analysis, and urinalysis. A modified water deprivation response test was also performed in two of the dogs. Renal changes on postmortem examination in three of the dogs were found to be consistent with renal dysplasia. A possible explanation for the finding of hyposthenuria and the extreme polyuria and polydipsia in association with renal dysplasia may be lack of response to antidiuretic hormone owing to anomalous maturation of the renal tubules. Six other puppies from the two litters of dogs did not show any clinical signs of polyuria and polydipsia, although postmortem examination in one of them also revealed renal dysplasia. The clinical features of renal dysplasia may therefore vary greatly between individuals.     

Ultrasound-guided percutaneous drainage as the primary treatment for prostatic abscesses and cysts in dogs

Thirteen dogs with prostatic abscesses and cysts were treated using percutaneous ultrasound-guided drainage. Eight dogs were diagnosed with prostatic abscesses and five with cysts on the basis of cytopathological examination and bacterial culture of the prostatic fluid. Antibiotic therapy, based on culture and sensitivity results, was administered for a minimum of 4 weeks. Intact dogs were castrated after initial drainage. Repeat ultrasonography of the prostate was performed every 1 to 6 weeks, and any residual cavitary lesions were drained and fluid analysis repeated. The median number of drainage procedures required to completely resolve the lesions was two (range, one to four). No complications were observed after drainage, and clinical signs resolved in all dogs. None of the dogs developed clinical signs of recurrent abscesses or cysts in the follow-up period (median, 36 months; range, 10 to 50 months). Ultrasound-guided, percutaneous drainage of prostatic abscesses and cysts appears to be a useful alternative to surgical treatment in select dogs.     

Assessment of glomerular filtration rate with dynamic computed tomography in normal Beagle dogs

The objective of our study was to determine individual and global glomerular filtration rates (GFRs) using dynamic renal computed tomography (CT) in Beagle dogs. Twenty-four healthy Beagle dogs were included in the experiment. Anesthesia was induced in all dogs by using propofol and isoflurane prior to CT examination. A single slice of the kidney was sequentially scanned after a bolus intravenous injection of contrast material (iohexol, 1 mL/kg, 300 mgI/mL). Time attenuation curves were created and contrast clearance per unit volume was calculated using a Patlak plot analysis. The CT-GFR was then determined based on the conversion of contrast clearance per unit volume to contrast clearance per body weight. At the renal hilum, CT-GFR values per unit renal volume (mL/min/mL) of the right and left kidneys were 0.69 ± 0.04 and 0.57 ± 0.05, respectively. No significant differences were found between the weight-adjusted CT-GFRs in either kidney at the same renal hilum (p = 0.747). The average global GFR was 4.21 ± 0.25 mL/min/kg and the whole kidney GFR was 33.43 ± 9.20 mL/min. CT-GFR techniques could be a practical way to separately measure GFR in each kidney for clinical and research purposes.     

Nasal dermoid sinus cysts in the dog

OBJECTIVE: To describe the clinical and morphologic characteristics of nasal dermoid sinus cysts in the dog. STUDY DESIGN: Retrospective clinical study. ANIMALS: Six client-owned dogs. METHODS: Medical records (1995 to 1999) of 6 dogs that had a discharging sinus in the midline of the nose removed surgically were reviewed for signalment, physical examination, surgical and histopathologic findings, and outcome. RESULTS: Three golden retrievers, 1 springer spaniel, 1 cocker spaniel, and 1 Brittany spaniel with a history of intermittent discharge from a small opening in the midline on the bridge of the nose at the junction between the nasal planum and the skin were identified. The condition was unresponsive to antibiotic therapy, and previous surgical excision had been unsuccessful in 3 dogs. None of the dogs had any other congenital defects, and all dogs responded to complete surgical excision of the tract and cyst. On histopathologic examination of excised tissue, there were adnexal structures along a tract lined with stratified squamous epithelium, consistent with a developmental abnormality of ectodermal tissue. CONCLUSIONS: The lesions were diagnosed as nasal dermoid sinus cysts, similar to the congenital condition described in humans. Nasal dermoid sinus cysts are rare developmental defects related to abnormal development of the pre-nasal space and may extend into the cranial vault causing cerebral abscesses or recurrent meningitis. Complete surgical excision has a good prognosis. CLINICAL RELEVANCE: This is a new condition that should be added to the surgical differential diagnosis for a discharging sinus over the external nares in dogs.     

COMPUTED TOMOGRAPHY OF CANINE ELBOW JOINTS AFFECTED BY PRIMARY AND CONCOMITANT FLEXOR ENTHESOPATHY

Flexor enthesopathy is an important differential diagnosis for elbow lameness in dogs. The disorder can be a primary cause of elbow lameness or concomitant with other elbow pathology. Since treatment differs for primary and concomitant forms of flexor enthesopathy, a noninvasive method for distinguishing between them is needed. In the current prospective study, computed tomographic (CT) examination was performed before and after IV injection of contrast in 17 dogs with primary flexor enthesopathy, 24 dogs with concomitant flexor enthesopathy, 13 dogs with elbow dysplasia, and seven normal dogs. Dogs were assigned to groups based on results of clinical examination and at least three other imaging modalities. Computed tomographic lesions consistent with flexor enthesopathy were found in all clinically affected joints with primary flexor enthesopathy and in 29 of the 30 clinically affected joints with concomitant flexor enthesopathy. Those lesions were not found in sound elbows or joints affected by elbow dysplasia. Flexor lesions detected in dogs with primary flexor enthesopathy were not significantly different from those detected in dogs with the concomitant form. Findings indicated that CT can be applied to detect flexor enthesopathy, but a distinction between the primary and concomitant forms was not always possible. Authors recommend the use of multiple diagnostic techniques for treatment planning in affected dogs.     

Intrapericardial Cysts in the Dog

Intrapericardial cysts were identified as the cause of impaired cardiac filling in six young dogs. Pneumo-pericardiography and two-dimensional echocardiography showed the cysts in 2 of 2 dogs and in 4 of 4 dogs, respectively. One dog, which was also infected with heartworms, died before surgical excision of the cyst could be performed. In the remaining dogs, surgical excision of the cysts and subtotal pericar-diectomy was successfully accomplished. Histologic examination of the excised tissue from one dog suggested that it was a pericardial coelomic cyst. The gross and histologic characteristics of the cysts removed from the other five dogs resembled those of acquired cystic hematomas. The etiopathogenesis of these cysts was uncertain, but all cysts were connected to a fatty pedicle of tissue. In one dog, a stalk of tissue was observed to enter the pericardium through a small peritoneopericardial diaphragmatic hernia. In four dogs, the stalk of tissue was adhered to the apex of the parietal pericardium. These observations suggested that intrapericardial cysts, in some dogs, develop in association with, and possibly as a result of, congenital herniation and entrapment of omentum or a portion of the falciform ligament into the pericardial sac. (Journal of Veterinary Internal Medicine 1993; 7:364–369. Copyright © 1993 by the American College of Veterinary Internal Medicine.)     

Retrospective analysis of spinal arachnoid cysts in 14 dogs

Spinal cord dysfunction secondary to spinal arachnoid cysts (SACs) has been reported previously in dogs. This retrospective study reviews the clinical signs, radiographic findings, and outcome after surgical resection of SACs in 14 dogs. Plain vertebral column radiographs and myelography were done in all dogs. Computed tomography (CT) was done in 7 dogs and magnetic resonance (MR) imaging in 3 dogs. Affected dogs were between 1 and 12 years of age, and 8 of 14 were Rottweilers. Abnormalities detected on neurological examination depended on the location of the SAC. Five dogs had bilobed or multiple SACs. SACs were located in the cervical vertebral column in 11 dogs and in the thoracic vertebral column in 4 dogs. All dogs had dorsally or dorsolaterally located SACs. Two dogs also had additional ventrally located SACs. Spinal cord compression secondary to intervertebral disc extrusion or protrusion was demonstrated at the site of the SACs in 2 dogs. Surgical resection of the SACs was completed in all dogs. Eleven dogs were available for follow-up. Five weeks postoperatively, 7 dogs improved in neurological function, with some residual ataxia and paresis in 6 of these dogs. Neurological function had deteriorated in 4 dogs. It was concluded from this study that Rottweilers have a higher incidence of SACs than other breeds of dog. Furthermore, bilobed or multiple SACs can occur commonly, and myelography effectively localized SACs in dogs. Surgical resection of SACs resulted in improvement in neurological function in the majority of treated dogs.     

Spinal arachnoid cyst in four dogs: diagnosis, surgical treatment and follow-up results

Spinal arachnoid cysts were diagnosed in four dogs; two schipperkes and two rottweilers. Myelography showed the cysts to be localised either at the second to third caudal vertebrae or between the eighth and tenth thoracic vertebrae. The cysts were drop-shaped with a dorsal midline localisation, intradural in the arachnoid space, and with a cranial opening. Surgical treatment was performed by one of two techniques; durotomy with drainage or durectomy with resection. As the pathological examination in one case revealed a lining of hyperplastic pia-arachnoid meningothelial cells in the cyst, it was assumed that the cyst originates from a developmental disturbance during formation of the arachnoid membrane. Follow-up studies were carried out from 10 months to four years postoperatively and revealed that there were no further problems in three out of four of the dogs during this period.     

INTRACRANIAL RING ENHANCING LESIONS IN DOGS: A CORRELATIVE CT SCANNING AND NEUROPATHOLOGIC STUDY

This retrospective analysis of 15 dogs with postcontrast ring enhancing brain lesions, each detected by a single Computed Tomography [CT] examination, searched for any association between their CT appearance and the pathologic diagnosis. In a subgroup of these dogs [n = 7] necropsied within 2 days of the last CT scan, we evaluated whether there was any anatomic correlation between the ring zone and the histopathologic features of the lesions. Our study consisted of eight dogs with primary brain tumors [3 meningiomas, 3 astrocytomas, 1 mixed glioma, 1 oligodendroglioma], 4 with metastatic brain tumors [2 fibrosarcomas, 1 mammary carcinoma, 1 melanoma] and 3 with non-neoplastic brain lesions [2 intraparenchymal hemorrhages, 1 pyogranulomatous meningoencephalitis]. The overall size and shape of the contrast enhancing CT lesions, as well as the thickness, surface texture and degree of enhancement of the ring were subjectively evaluated. No association was found between the CT lesion characteristics and the pathologic diagnosis. In the sub-group of dogs euthanatized within 2 days of the CT examination, distinct histologic features which anatomically correlated with the zone of ring enhancement were found in 3 of 7 lesions. The findings of this study are consistent with those of ring-enhancing lesions in people, and indicates that CT ring enhancement is a non-specific phenomenon which can occur in a variety of neoplastic and non-neoplastic lesions in the dog.