Cutaneous Botryomycosis in a Campbell’s Russian Dwarf Hamster (Phodopus campbelli)

A 10-month-old male Campbell’s Russian hamster (Phodopus campbelli) presented with a mass on the left forelimb. The mass was surgically excised, and the results of histopathology yielded a diagnosis of cutaneous botryomycosis, with corresponding clusters of large colonies of Gram-positive cocci. The results of the bacteriologic examination revealed Staphylococcus epidermidis. There was no evidence of patient immunosuppression based on diagnostic test results (e.g., hematology, plasma biochemistry panel, and serum electrophoresis). The mass recurred 5 months after resection. Surgical treatment was declined by the owner and an attempt to treat with antimicrobial medication was met with limited success. The animal was euthanized 7 months following the initial presentation. On histopathologic examination, a recurrent cutaneous botryomycosis was identified, associated with hepatic and splenic extramedullary granulopoiesis and hepatic pyogranulomas without granules and identifiable bacteria.     

Oestrogen-induced bone marrow aplasia in a dog with a Sertoli cell tumour

A 10-year-old male Drahthaar dog with unilateral cryptorchidism was examined because of feminisation and myelotoxicity. Radiography and ultrasonography revealed an abdominal mass which was surgically removed. The mass was identified as a Sertoli cell tumour on histological examination. Findings on bone marrow examination were compatible with aplasia due to the oestrogens secreted by the tumoral cells. Treatment with fluids, antibiotics, whole blood transfusions, corticosteroids and lithium carbonate was unsuccessful. Survival time was 22 days after surgery.     

Systemic infection with Geomyces organisms in a dog with lytic bone lesions

CASE DESCRIPTION: A 5-year-old neutered male mixed-breed dog was evaluated by a veterinarian because of a 4-week history of progressive lethargy and poor appetite; the dog was then examined at a referral hospital. CLINICAL FINDINGS: Hyperglobulinemia was identified via serum biochemical analyses performed before and after arrival at the hospital. Lysis of sternebrae 1 and 2 and sternal lymphadenopathy were detected radiographically. Fine-needle aspirates were collected from the affected sternebrae and lymph node for cytologic examination; findings were consistent with pyogranulomatous inflammation associated with fungal infiltrates. Geomyces organisms were identified via microbial culture of sternebral aspirates. TREATMENT AND OUTCOME: Treatment consisted of oral administration of itraconazole. After 6 months, remodeling of the affected sternebrae and resolution of sternebral lysis were evident radiographically. Geomyces organisms and pyogranulomatous infiltrates persisted despite clinical improvement. Treatment with itraconazole was continued for an additional 3 months. CLINICAL RELEVANCE: Infection with Geomyces organisms is typically localized to the skin and nail beds. In the dog of this report, systemic dissemination of Geomyces organisms resulted in lysis of the first 2 sternebrae. Cytologic examination of fine-needle aspirates and microbial culture of samples of the affected sternebrae were important diagnostic tests for successful identification of the organism. Despite 6 months of itraconazole administration and evidence of clinical improvement, fungal organisms persisted in the dog's affected sternebrae. Practitioners should include Geomyces infection among the differential diagnoses for suspected systemic mycosis and should perform cytologic examination and microbial culture of affected tissue throughout treatment of affected dogs.     

Cutaneous actinomycosis and nocardiosis in dogs: 48 cases (1980-1990).

Medical records of 48 dogs with cutaneous actinomycosis or nocardiosis were reviewed. Male, large-breed dogs kept outdoors were overrepresented. The mean age at admission was 3.6 years. Cutaneous swelling (68%), abscesses (65%), draining tracts (48%), fever (36%), and signs of pain (13%) were the most common clinical findings. The cervicofacial area was affected in 48% of the dogs. Abdominal and thoracic wall involvement was less common. Leukocytosis, neutrophilia with left shift, monocytosis, and hyperglobulinemia were common. The diagnosis was confirmed by cytologic examination, bacteriologic culture, or histologic examination. Gram-positive filamentous bacteria were seen in 69% of the fine needle aspirates and in 50% of the biopsy specimens. Actinomyces spp were isolated from cutaneous lesions in 27 (60%) dogs. Nocardia asteroides was isolated from 1 dog. Treatment consisted of surgical debridement, drainage, and administration of antibiotics in 29 dogs (group A) and antibiotics alone in 13 dogs (group B). The infection redeveloped in 10 (42%) group-A dogs and 6 (60%) group-B dogs. Of the 10 group-A dogs with recurrent infection, 6 had resolution after a second surgery and 4 were euthanatized. Of the 6 group-B dogs, 1 had resolution after surgery, 4 were euthanatized or died because of persistent disease, and 1 had an unresolved infection. The combination of surgery and antibiotic treatment appeared to be superior to antibiotic treatment alone in resolving cutaneous Actinomyces and Nocardia infections.     

Nontraumatic rupture of an adrenal gland tumor causing intra-abdominal or retroperitoneal hemorrhage in four dogs

Diagnosis and surgical management of intra-abdominal or retroperitoneal hemorrhage in 4 dogs with rupture of an adrenal gland tumor were determined. All 4 dogs were lethargic and weak with pale mucous membranes on initial examination. Three dogs did not have any history of clinical signs of hyperadrenocorticism or pheochromocytoma prior to examination. In 3 of the dogs, a mass in the area of the adrenal gland was identified with ultrasonography prior to surgery. All dogs developed ventricular premature contractions before or during anesthesia. Three dogs survived adrenalectomy; 1 dog was euthanatized during surgery because of an inability to achieve adequate hemostasis. The remaining 3 dogs all survived more than 5 months after surgery; 1 was euthanatized 9 months after surgery because of rupture of a hepatic mass. On the basis of these results, we suggest that hemodynamic stabilization followed by adrenalectomy is the treatment of choice for dogs with nontraumatic rupture of an adrenal gland tumor and resulting life-threatening hemorrhage.     

A case report of canine protothecosis

A 10-year-old spayed mongrel dog was referred with repeated intercurrent hematochezia and anal bleeding. The dog was vigorous and had a normal appetite, and the fecal test showed no abnormal signs. Despite treatment primarily with sulfasalazine, the condition did not improve and unilateral blindness developed. A Prototheca zopfii infection was identified by further examination with bowel culture on Sabouraud's agar without cyclohexane and antibiotics. Subsequent to a vision loss in the other eye, the dog died showing signs of neurological disorder.     

Pulmonary botryomycosis in a Scottish highland steer.

Pertinent necropsy findings in a 5 1/2-year-old Scottish Highland steer with chronic intractable pneumonia and cough were limited to the pulmonary system. The accessory lobe of the lung was collapsed, scarred, and multifocally adhered to parietal pleura. A polypoid mass almost completely obstructed the lobar bronchus and protruded into the trachea; mucopurulent exudate distended more distal bronchi. Botryomycosis was diagnosed when histologic examination revealed pyogranulomatous pneumonia with eosinophilic granules and "club" formation surrounding colonies of gram-positive cocci. Staphylococcus aureus was cultured from the lung. Botryomycosis is an unusual response to infection with common bacteria and is characterized by pyogranulomatous inflammation with formation of eosinophilic granules surrounding colonies of gram-positive cocci or gram-negative bacilli. Among domestic species, staphylococcal botryomycosis is most common as a wound infection in horses or as mastitis in cows and sows. Pulmonary botryomycosis is rare in horses, humans, and guinea pigs and apparently has not been reported in cattle.     

Septic pericardial effusion associated with pulmonary and pericardial botryomycosis in a dog

The authors report a case of septic pericardial effusion resulting in cardiac tamponade associated with intrathoracic botryomycosis in a dog. Septic pericarditis and a pulmonary mass were diagnosed, and subtotal pericardiectomy and lobectomy of the affected pulmonary areas were carried out. Histopathology of the excised tissue showed changes supportive of botryomycosis--namely a pyogranulomatous inflammation with neutrophils centred around amorphous homogeneous eosinophilic material and club-like bodies containing Gram-positive bacterial cocci present in the centre. The patient recovered well following surgery and antibiotic therapy. To the authors' knowledge, this is the first report of pulmonary botryomycosis in the dog and the first report of this condition presented with pericardial involvement and cardiac tamponade in any species.     

Cervical syringohydromyelia secondary to a brainstem tumor in a dog

An 11-year-old male Pekingese was evaluated because of a history of head tilt. Neurologic examination revealed a right-sided head tilt, ataxia, scoliosis, and proprioceptive deficits. Diagnostic testing included magnetic resonance imaging (MRI) of the head and neck. After IV administration of gadopentetate dimeglumine, an extra-axial, highly contrast-enhanced mass in the brainstem, cerebellar herniation, and syringohydromyelia were detected via MRI. The dog was treated with corticosteroids and radiation therapy of the mass for 4 weeks (total dose, 42.5 Gy). Magnetic resonance imaging was repeated 9 weeks and 6 months after radiation therapy; compared with the initial findings, a reduction in the size of the brainstem mass was observed in both MRI scans. The third MRI scan also revealed a normal cerebellar shape, no evidence of herniation, and resolution of syringohydromyelia in the dog at that time. It is recommended that whenever syringohydromyelia is observed via MRI, a primary cause (cranial or caudal to the affected region) should be sought.     

Cutaneous Serratia marcescens infection in two dogs

We describe two canine cases of cutaneous infection caused by Serratia marcescens. A 2-year-old castrated male mixed dog (Case 1) presented with multiple ulcerations on the dorsal trunk, which were observed 4 days after shampooing. A 4-year-old male wolf shepherd mix dog (Case 2) presented with ulceration and purulent discharge on the nasal bridge. Cytological examination of both cases revealed pyogranulomatous inflammatory cells with rod-like infectious agents identified as S. marcescens in aerobic bacterial culture. Both patients were treated with oral antibiotics and topical chlorhexidine. Case 1 received enrofloxacin 10 mg/kg once daily for 1 week, followed by trimethoprim/sulfamethoxazole 15 mg/kg twice daily for 3 weeks. Case 2 received doxycycline 10 mg/kg twice daily for 4 weeks. No skin lesions were detected 2 weeks after the initial administration. The antibiotics were discontinued after a total 4 weeks of administration, and the skin lesions did not reappear.     

EXTRA-ABDOMINAL CHONDROLIPOMA IN A DOG

A 10-year-old male maltise dog was presented for evaluation of a gradual abdominal enlargement, which had developed over 2 years. (On the radiograph of the abdomen, a significant distention of the abdomen with a large accumulation of fat could be seen.) The mass effect was noticeable because of the rightward displacement of the viscera. There was multifocal amorphous mineralization, mostly in the right abdomen. Computed tomography (CT) identified a 13 x 13 x 10 cm mass, most likely an intra-abdominal lipoma, by which the digestive tract had been displaced in the abdomen. It was only during surgery, however, that the mass was found to be located between the peritoneum and transversus abdominis muscles and the rectus abdominus muscle. It was completely resected. Histopathological examination revealed that the mass was chondrolipoma. The amorphous radiopaque lesion on the images corresponded to cartilaginous tissues with calcification. There has been no recurrence for 10 months. This is the first report of an extra-abdominal chondrolipoma in dogs. Cartilaginous metaplasia of lipoma, located in the abdominal area, should be included in the differential diagnosis for multifocal amorphous mineralization.     

Septic pleuritis and abdominal abscess formation caused by Rhodococcus equi in a foal

A 3-month-old female Arabian horse was evaluated because of fever, respiratory distress, lethargy, and decreased appetite of 5 days' duration. Pleural effusion was diagnosed on the basis of ultrasonographic and radiographic examinations. Cytologic examination of pleural fluid collected via thoracocentesis revealed septic inflammation; bacteriologic culture of a sample of that fluid yielded Rhodococcus equi. A large intra-abdominal mass adjacent to the body wall was identified ultrasonographically. A specimen of the mass was collected via aspiration; the specimen was identified cytologically as purulent exudate that contained large numbers of rod-shaped bacteria, which confirmed abdominal abscess formation. Bacteriologic culture of a sample of the exudate also yielded R. equi. The foal was treated with azithromycin (10 mg/kg [4.5 mg/lb], PO, q 24 h for 5 days then q 48 h) and rifampin (5 mg/kg [2.3 mg/lb], PO, q 12 h) for 8 weeks and metronidazole (15 mg/kg [6.8 mg/lb], PO, q 8 h) for 3 weeks. Clinically, the foal responded to antimicrobial treatment within 2 weeks. At 8 weeks after the initial evaluation, ultrasonographic examination of the foal revealed resolution of the pleural effusion and abdominal abscess. In foals, R. equi infection typically results in pyogranulomatous pneumonia, and pleural effusion is an uncommon clinical sign. The combination of azithromycin and rifampin appears to be an effective treatment for R. equi infection in foals.     

Hypophysitis,Panhypopituitarism, and Hypothalamitis in a Scottish Terrier Dog

A 6‐year old male neutered Scottish Terrier was referred with a 1 week history of progressive lethargy and anorexia. Neurological examination localized a lesion to the forebrain and hormonal testing showed panhypopituitarism. Magnetic resonance imaging (MRI) of the brain revealed a rounded, well‐defined, suprasellar central mass. The mass was slightly hyperintense to the cortical grey matter on T2‐weighted (T2W), hypointense on T1‐weighted (T1W) images and without T2* signal void. There was a central fusiform enhancement of the mass after contrast administration which raised the suspicion of a pituitary neoplasm. Rapid deterioration of the dog prevented further clinical investigations. Histopathologic examination revealed a lymphocytic panhypophysitis of unknown origin suspected autoimmune involving the hypothalamus (hypothalamitis). This is a unique case report of a dog presenting with inflammatory hypophysitis and hypothalamitis of suspected autoimmune origin with detailed clinical, MRI, histology and immunohistochemistry findings.     

Bilateral pyelonephritis and hydroureter associated with metastatic adenocarcinoma in a dog

Metastatic adenocarcinoma, involving the trigone of the urinary bladder, resulted in bilateral pyelonephritis and hydroureter in an aged dog. Salient physical examination and clinicopathologic findings included bacterial urinary tract infection, renal pain response to abdominal palpation, and the observation of WBC casts in urine sediment. A good response to antimicrobial drug administration was observed initially; however, the dog later was euthanatized because of progressive renal disease. Necropsy revealed extensive peritoneal carcinomatosis with metastatic lesions causing occlusion of both ureters. Ostensibly, metastatic carcinoma involving the trigone resulted in urine stasis and enhanced the development of renal infection and hydroureter.     

Dynamic left ventricular outflow tract obstruction secondary to hypovolemia in a German Shepard dog with splenic hemangiosarcoma

Dynamic left ventricular outflow tract obstruction (DLVOTO) is a common condition in cats and humans. In this case report, a dog is described with DLVOTO secondary to severe intra-abdominal hemorrhage caused by a hemangiosarcoma. The dog was a 9-year-old, 35.7-kg, spayed female German Shepard dog that presented with a history of tachypnea and collapse. A Levine II/VI systolic murmur was present at the heart base. Abdominal ultrasonography revealed a splenic mass and a large amount of ascites. Echocardiography showed a reduced left ventricular diameter and an increased aortic velocity caused by systolic anterior motion (SAM) of the mitral valve apparatus. The heart murmur and the SAM were resolved after treatment including a splenectomy and a blood transfusion.     

Ventricular pneumocephalus and septic meningoencephalitis secondary to dorsal rhinotomy and nasal polypectomy in a dog

CASE DESCRIPTION: A 4-year-old sexually intact female French Bulldog was evaluated because of lethargy, anorexia, and chronic rhinitis-sinusitis. The dog had nasal discharge of 18 months' duration; dorsal rhinotomies were performed 3 months and 2 weeks prior to referral. CLINICAL FINDINGS: On initial evaluation, intraventricular pneumocephalus and sinusitis were diagnosed; CSF analysis revealed high total protein concentration and mononuclear pleocytosis. The dog's condition improved with treatment. Two weeks after discharge, it was treated by a local veterinarian because of upper airway obstruction; 3 days later, the dog was referred because of seizures. Computed tomography revealed a large fluid-filled, left lateral ventricle and a soft tissue mass protruding through a cribriform plate defect. The mass was histologically consistent with brain tissue. Findings of clinicopathologic analyses were unremarkable. Results of cytologic examination of a CSF sample were indicative of septic, suppurative inflammation, and bacteriologic culture of CSF yielded Escherichia coli. TREATMENT AND OUTCOME: Amputation of the herniated olfactory bulb and antimicrobial treatment resolved the septic meningoencephalitis, but neurologic deficits recurred 6 weeks later. Definitive correction of the cribriform plate defect with bone and fascial grafts was attempted. Postoperative rotation of the bone graft resulted in cerebral laceration and hemorrhage, and the dog was euthanized. CLINICAL RELEVANCE: Findings suggest that following dorsal rhinotomy and nasal polypectomy surgery, the dog developed herniation of the left olfactory bulb, intra-ventricular pneumocephalus, and septic meningo-encephalitis because of a cribriform plate defect. Care must be taken to prevent rotation of bone grafts used in cribriform defect repair.     

Primary pulmonary osteosarcoma in a dog

An 11-year-old mixed breed dog was referred because of coughing and painful swelling of the distal extremities which had not resolved with antibiotic treatment. A consolidated left cranial lung lobe and hypertrophic osteopathy were identified by radiographs. A unique feature of this report is the marked, rapid reduction in pain and lameness associated with hypertrophic osteopathy after treatment with corticosteroids. Histological examination of an 8 cm diameter, spherical mass found in the excised cranial lung lobe revealed osteosarcoma. No evidence of local or distant metastases was present. The dog survived one year after diagnosis.     

Nodular immunocyte-derived (AL) amyloidosis in the trachea of a dog

A 7-year-old castrated male Miniature Schnauzer was examined because of labored breathing and episodes of respiratory distress that progressed to collapse. On cervical radiographs, a focal soft tissue mass in the caudal cervical portion of the trachea was observed, and during tracheoscopy, a 1 x 1 cm, pedunculated, multinodular, pink, intraluminal mass extending from the dorsal tracheal membrane and obstructing approximately 80% of the tracheal lumen was seen. Tracheal resection and anastomosis was performed to remove the mass, and the dog recovered without complications. On histologic examination, the mass consisted of a large accumulation of homogeneous, faintly fibrillar eosinophilic material admixed with a predominantly plasma cell infiltrate; examination of sections stained with thioflavin T and Congo red stain confirmed that the eosinophilic material was amyloid. A diagnosis of nodular, immunocyte-derived (AL) amyloidosis was made. Seventeen months after surgery, the dog had a relapse of respiratory distress because of an extramedullary plasmacytoma involving the trachea.     

A Review of Disorders of the Gallbladder and Extrahepatic Biliary Tract in the Dog and Cat

Disorders of the gallbladder and extrahepatic biliary tract in the dog and cat can easily be confused with other intra-abdominal disorders. This confusion results because many times the clinical course and signs of biliary tract disease are similar to these other intra-abdominal disorders. This review discusses the normal anatomy and physiology of the gallbladder, bile duct, and bile in the dog and cat and then summarizes the historic, physical examination, clinicopathologic, diagnostic, histologic and therapeutic aspects of all the cases of extrahepatic biliary tract disease reported in the veterinary literature.     

Ectopic cervical thymic carcinoma in a dog

A 10-year-old male German shepherd dog was referred for evaluation of a cranial cervical mass causing progressively worsening respiratory distress. A fine-needle aspirate of the mass was obtained and the cytology results were compatible with a carcinoma. The dog underwent chemotherapy without clinical improvement and was ultimately euthanased because of clinical deterioration. At post-mortem examination, an irregular multi-lobated mass in the cranial cervical region was observed causing ventro-lateral tracheal deviation. Histopathology and immunohistochemistry revealed a mixed population of CD3 lymphocytes and macrophages in an exuberant fibrous stroma, associated with dispersed cytokeratin-positive epithelial cells with marked eosinophilic cytoplasm. Some of the epithelial cells were arranged in concentric clusters that were interpreted as Hassall's corpuscles. Histopathological examination of the thyroid gland revealed several neoplastic emboli composed of epithelial cells similar to those observed in the cervical mass. To the authors' knowledge, this is the first report of an ectopic cervical thymic carcinoma in a dog.