Neodymium:yttrium-aluminum-garnet laser-assisted excision of progressive ethmoid hematomas in horses: 20 cases (1986-1996)

OBJECTIVE: To describe a technique of contact neodymium:yttrium-aluminum-garnet (Nd:YAG) laser-assisted excision of progressive ethmoid hematoma (PEH) in horses, to determine the recurrence rate of clinical signs of PEH in horses with follow-up time of a minimum of 12 months, and to compare this result with reported results achieved by using conventional techniques. DESIGN: Retrospective study. ANIMALS: 21 horses with 26 PEH. PROCEDURE: Medical records of all horses with PEH treated by Nd:YAG laser excision from December 1986 through August 1996 were analyzed. Twenty-one horses underwent unilateral (18 surgeries) or bilateral (14) frontonasal bone flap with excision of the mass, using an Nd:YAG laser. One horse with bilateral PEH underwent a unilateral bone flap twice, 1 year apart. RESULTS: 1 horse died. Four of 20 horses with followup times of 12 months or longer had recurrence of PEH. The PEH recurrence rate was 20% (5/25 PEH). Three of 6 horses with bilateral lesions had recurrence of PEH. Recurrence rate for horses that had bilateral PEH (3/6 horses) was greater than for horses with unilateral PEH (1/14 horses). CLINICAL IMPLICATIONS: Treatment of PEH by Nd:YAG laser excision through a frontonasal bone flap results in a recurrence rate comparable with that reported for conventional techniques. Horses with bilateral lesions are more likely to have a recurrence of PEH.     

Marginal excision of low-grade spindle cell sarcoma of canine extremities: 35 dogs (1996-2006)

Objective— To evaluate recurrence rate and disease-free interval (DFI) of dogs with low-grade soft tissue spindle cell sarcoma of the extremities treated by marginal excision.
Study Design— Retrospective study.
Animals— Dogs (n=35) with soft tissue low-grade spindle cell sarcoma.
Methods— Medical records were reviewed and dogs that had marginal surgical resection of low-grade soft tissue spindle cell sarcoma at or distal to elbow and stifle were included.
Results— Histopathologic margins were dirty (12 dogs), clean but close (12), and clean (11). Follow-up after surgery occurred from 210 to 2202 days (minimum, 180 days). Local recurrence and metastatic rates were 10.8% and 0%, respectively. Median DFI and survival time were not reached, because <50% of dogs died of disease-related events. Mean DFI and mean survival time were 697.8 days (95% CI: 559.7–836 days) and 703.5 days (95% CI: 566.6–840.5 days), respectively. There were no significant differences among survival functions stratified by histologic margins.
Conclusion— Marginal surgical excision without adjuvant treatment of low-grade soft tissue spindle cell sarcoma of the extremities results in a low local recurrence rate.
Clinical Relevance— Low-grade spindle cell sarcomas located at or distal to the elbow and stifle joints can be excised without need for wide or radical surgery.     

Feline vaccine-associated fibrosarcoma: an ultrastructural study of 20 tumors (1996-1999)

Twenty feline vaccine-associated sarcomas were examined by transmission electron microscopy. Tumors contained pleomorphic spindle cells, histiocytoid cells, and giant cells. Most tumors contained myofibroblasts, which had morphologic features similar to those of fibroblasts. These cells were further distinguished by subplasmalemmal dense plaques and thin cytoplasmic actin myofilaments organized as elongated bundles concentrated at irregular intervals forming characteristic dense bodies. Intracellular crystalline particulate material was found in 5 of the 20 tumors. Energy dispersive X-ray spectroscopy was used to identify the crystalline material within one tumor as aluminum-based. One tumor from a feline leukemia virus-infected cat contained budding and immature retroviral particles.     

Osteogenic sarcoma and cisplatin chemotherapy in dogs: 16 cases (1986-1989).

Sixteen dogs, given adjuvant cisplatin chemotherapy after amputation for osteogenic sarcoma of the appendicular skeleton, had a median survival time of 413 days. Ten dogs (62%) were alive 1 year after amputation. Dogs were given cisplatin at a dosage of 50 mg/m2 of body surface every 4 weeks for a total of 6 cisplatin treatments, or until metastatic disease was detected. Cisplatin chemotherapy was well-tolerated by most dogs, with only 1 dog developing serious gastrointestinal toxicosis, requiring hospitalization. Results of this study support other investigators' findings that when a cisplatin chemotherapy-based protocol is administered, survival times after amputation can be prolonged for dogs with osteogenic sarcoma.     

Breeding soundness of beef bulls after circumcision: 33 cases (1980-1986)

Case records of 33 beef bulls that had preputial prolapses and underwent circumcisions were reviewed. Data retrieved included age, breed, duration of preoperative medical treatment, complications of surgery, length of time from surgery to first breeding, ability of bull to copulate, duration of active breeding, and complications resulting in breeding unsoundness. The mean age of all bulls was 3.5 years (1 to 7 years). Breeds represented included Santa Gertrudis (n = 13), Beefmaster (n = 8), Brangus (n = 7), Brahman (n = 4), and Angus (n = 1). The mean duration of medical treatment before surgery for all bulls was 16.4 days (2 to 38 days). There was no statistically significant difference between the mean duration of medical treatment before surgery between bulls that became breeding sound (16 days), compared with those that were breeding unsound (19 days). However, bulls requiring more than 14 days of medical treatment before surgery were approximately 3 times (relative risk, 2.8) more likely to develop postoperative complications than those bulls requiring 14 days of treatment or less. Eleven bulls (33%) developed one or more postoperative complications. The complications resolved in 4 bulls, but 7 were never able to breed. Of these 7 bulls, 4 had problems directly related to the circumcision, 2 had extensive fibrosis of the prepuce already present at surgery, and 1 was discharged from the hospital with no apparent complications but was never able to breed. Twenty-five of the 33 bulls (76%) were breeding sound for 1 or more years after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of medical and surgical treatment for impaction of the small colon in horses: 84 cases (1986-1996)

OBJECTIVE: To characterize clinical findings and compare effects of treatment and outcome for horses treated medically or surgically for impaction of the small colon. DESIGN: Retrospective study. ANIMALS: 84 horses with impaction of the small colon. PROCEDURE: Medical records were reviewed for history, physical examination findings, laboratory values, treatment, response to treatment, complications, out-come, and necropsy findings. RESULTS: 47 horses were treated medically and 37 horses were treated surgically. Significant differences between groups were not identified for duration of clinical signs, physical examination findings, or laboratory values. Horses treated surgically were hospitalized longer than horses treated medically. Complications recorded during hospitalization included diarrhea, jugular thrombophlebitis, recurrent colic, fever, and laminitis. Salmonella organisms were isolated from 20 horses. Horses treated surgically were more likely to have signs of moderate abdominal pain, gross abdominal distention, and positive results for culture of Salmonella spp than horses treated medically. Follow-up information was available for 27 horses treated medically and 23 horses treated surgically. Twenty-four (72%) and 21 (75%) of the horses, respectively, survived and were being used for their intended purpose at least 1 year after treatment. CLINICAL IMPLICATIONS: Colitis may be a predisposing factor for impaction of the small colon in horses. Prognosis for horses treated surgically or medically is fair.     

Pericarditis in horses: six cases (1982-1986)

Records of 6 horses with pericarditis were reviewed. Septic pericarditis was suspected in all horses, based on historic and clinical findings. In horses 1, 2, and 4, cytologic examination of the pericardial effusion revealed acute inflammation with severe neutrophil degeneration. In horses 3 and 5, cytologic examination of pericardial fluid revealed subacute inflammation with degenerated neutrophils, and in horse 6, chronic active inflammation, with well preserved neutrophils. In horses 1 and 3, bacteria were identified on cytologic examination of pericardial fluid. Results of microbiologic cultures of pericardial fluid were positive in horse 3. All horses were treated with broad-spectrum antibiotics. An indwelling pericardial catheter was used to lavage and directly administer antibiotics into the pericardial sac. Horses 1, 4, 5, and 6 survived, horse 2 died of unrelated causes, and horse 3 was euthanatized at the owner's request. Surviving horses returned to athletic performance.     

Blastomycosis in cats: five cases (1979-1986)

Medical records of 5 cats with blastomycosis examined at the University of Tennessee Veterinary Teaching Hospital from 1979 to 1986 were reviewed. Clinical signs of blastomycosis varies depending on the organ(s) affected, but respiratory tract disease was most common, followed by CNS signs and ocular problems. A definitive diagnosis was made by identification of characteristic fungal organisms in biopsy or necropsy specimens. Two cats treated with amphotericin B did not respond to treatment and died or were euthanatized. The lungs, brain, eyes, and lymph nodes commonly were affected, but one cat had only cutaneous and regional lymph node involvement. The respiratory tract appeared to be a common primary site of infection, with dissemination to other organ systems. The typical host response was a pyogranulomatous cellular infiltrate with numerous fungal organisms evident.     

Cholelithiasis in horses: ten cases (1982-1986)

Ten horses with clinical signs consistent with cholelithiasis were evaluated. Fever, icterus, mild intermittent colic, and weight loss were reported. Clinical laboratory abnormalities included leukocytosis, hyper-proteinemia, and hyperfibrinogenemia. Gamma glutamyltransferase and liver isoenzyme of lactate dehydrogenase activities also were high. Choleliths were observed via ultrasonography of the liver in 5 of the 8 horses evaluated, and increased echogenicity of the hepatic parenchyma and dilated bile ducts were observed in all horses. Seven horses were treated medically, 5 of which died or were euthanatized. Three horses were treated surgically, of which only 1 survived. Cholelith composition varied, but cholesterol, calcium bilirubinate, and mixed bile pigments were most commonly observed.     

Pyelonephritis in cows: 15 cases (1982-1986)

Medical records of 15 adult cows with a final diagnosis of pyelonephritis were evaluated retrospectively. Only 3 cows had obvious clinical signs that indicated urinary tract disease. Physical examination, including rectal and vaginal examinations, and urine chemical reagent strip screening detected abnormalities in all 15 cows and allowed subsequent confirmation by culture results of urine samples obtained using a catheter. Bacteriologic cultures of urine revealed Corynebacterium renale infection in 6 cows and Escherichia coli infection in 9 cows. Long-term treatment with antimicrobial drugs resulted in recovery in 9 of 11 treated cows. Of these, 4 of 4 cows with C renale infection and 5 of 7 cows with E coli infection recovered; the remaining 2 cows with E coli infection died.     

Keratomas in horses: seven cases (1975-1986)

The diagnosis of keratoma in 7 horses and their treatment and outcome were evaluated. Horses were 2 to 20 years old, of various breeds, and were intact or castrated males. All were lame, and 6 horses had had previous injuries of the affected hoof that had not responded to prior treatments. Only 1 hoof was affected in each horse. Keratomas were beneath the hoof wall (6 horses) or sole (1 horse). Radiographically, a circular or semicircular defect with a discrete margin was present in the distal portion of the third phalanx in 3 horses. Grossly, keratomas were firm solitary masses (1.5 to 5 cm diameter); gray, tan, or yellow; and oval or conical. Keratomas were excised from beneath the hoof wall by removing a section of hoof wall (5 horses) or by undermining the wall beginning at its junction with the sole (1 horse). A keratoma beneath the sole in 1 horse was excised by excavating the sole to the level of the palmar surface of the third phalanx. Keratoma was verified microscopically by the presence of characteristic rings of squamous epithelial cells with abundant keratin. Purulent exudate and inflammatory infiltrate often were present concurrently, reflecting an associated localized infection. Aftercare included daily application of an antiseptic iodine solution and foot bandages, and shoeing with a treatment plate several weeks after surgery. Hoof and sole defects healed completely between 6 months and 1 year. By 1 year after surgery, 6 horses were sound, and keratoma had not recurred.     

Risk of adverse effects in pneumonic foals treated with erythromycin versus other antibiotics: 143 cases (1986-1996)

OBJECTIVE: To determine whether foals with pneumonia that were treated with erythromycin, alone or in combination with rifampin or gentamicin, had a higher risk of developing adverse effects, compared with foals treated with trimethoprim-sulfamethoxazole (TMS), penicillin G procaine (PGP), or a combination of TMS and PGP (control foals). DESIGN: Retrospective study. ANIMALS: 143 foals < 240 days old. PROCEDURE: Information on age, sex, breed, primary drug treatment, total days of treatment with the primary drug, and whether the foal developed diarrhea, hyperthermia, or respiratory distress was obtained from the medical records. Relative risk (RR) and attributable risk (AR) were calculated to compare risk of adverse reactions between foals treated with erythromycin and control foals. RESULTS: Only 3 (4.3%) control foals developed diarrhea; none developed hyperthermia or respiratory distress. Foals treated with erythromycin had an 8-fold risk (RR, 8.3) of developing diarrhea, compared with control foals, and increased risks of hyperthermia (AR, 25%) and respiratory distress (AR, 15%). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that use of erythromycin to treat foals with pneumonia was associated with an increased risk of diarrhea, hyperthermia, and respiratory distress, compared with use of TMS or PGP.     

Pancreatic abscess in dogs: six cases (1978-1986)

Pancreatic abscess was diagnosed by exploratory celiotomy in 6 dogs. The most common clinical signs included acute onset of lethargy (n = 5), anorexia (n = 6), vomiting (n = 5), and diarrhea (n = 2). Physical examination revealed pain response to abdominal palpation (n = 5), depression (n = 5), icterus (n = 3), fever (n = 3), and cranial abdominal mass (n = 2). Consistent preoperative clinicopathologic abnormalities included leukocytosis with left shift, observance of toxic neutrophils on the blood smear, hyperlipasemia, hyperamylasemia, hyperbilirubinemia, and increased serum alkaline phosphatase activity. In 5 of 6 dogs, abdominal radiography revealed increased soft tissue density in the cranial portion of the abdomen. Ultrasonography performed on 4 dogs confirmed pancreatic mass. In all dogs, exploratory celiotomy revealed a cavitary pancreatic mass that contained sterile, mucopurulent material. Histopathologic diagnoses included acute necrotizing or chronic-active pancreatitis and steatitis. Two dogs were euthanatized at the time of diagnosis, and the remaining 4 were treated by use of pancreatic debridement(s), open abdominal drainage, and intensive administration of fluids and antibiotics. One dog was euthanatized 4 days after surgery, because of progressive pancreatic abscessation. Three dogs recovered and were discharged.     

Disseminated histoplasmosis in dogs: 12 cases (1981-1986)

Diarrhea, intestinal blood loss, anemia, and lethargy were predominant clinical findings in 12 dogs with disseminated histoplasmosis. Young dogs were affected most commonly, with 6 dogs being 1 to 3 years old. A diagnosis of disseminated histoplasmosis was established on the basis of histologic or cytologic detection of Histoplasma organisms in intestinal or rectal mucosa in 7 dogs, in circulating leukocytes in 5 dogs, in bone marrow in 3 dogs, and in multiple tissues at necropsy in 1 dog (4 dogs had Histoplasma organisms detected in greater than 1 site). Anemia was detected in 10 dogs (PCV less than 20% in 3 dogs), and the anemia was inadequately regenerative or nonregenerative in 7. Hypoalbuminemia was detected in 9 dogs, and serum albumin concentrations were low (less than 1.0 g/dl) in 4 of the 9 dogs. Of 5 dogs treated with ketoconazole, 2 were in remission for greater than or equal to 1 year. Corticosteroid therapy may have exacerbated the disease in 4 dogs. Histoplasma infection of multiple organs was detected in 5 necropsied dogs.     

Idiopathic gonitis in heifers: 34 cases (1976-1986)

Acute suppurative arthritis of the stifle joint was diagnosed in 34 Holstein heifers between 1976 and 1986. Only 1 stifle joint was affected in each heifer; however, 1 heifer also had involvement of the contralateral radiocarpal joint. In each heifer, there was marked lameness and synovitis characterized by an effusion with high synovial fluid nucleated cell counts and total protein concentration. Seventy-four percent (25/34) of the heifers had radiographic evidence of an osteolytic lesion involving the lateral tibial plateau. Bacteriologic cultures of synovial fluid, synovial membrane, and bone yielded no growth. Eighteen of 23 (78%) affected heifers for which follow-up data was obtained became productive herd members after treatment.     

Disseminated histoplasmosis in cats: 12 cases (1981-1986)

Anemia, weight loss, lethargy, fever, anorexia, and interstitial lung disease were the predominant clinical findings in 12 cats with disseminated histoplasmosis. Some cats were examined because of dysfunction or lesions of bone, eyes, or skin. In most cases, the clinical signs were observed by the owner for 4 weeks or less before seeking veterinary care. Young cats were most commonly affected, with 7 of the 12 cats less than or equal to 1 year old. Identification of Histoplasma organisms in bone marrow aspirates was used to confirm the diagnosis of histoplasmosis in 11 of the 12 cats. Histoplasma infection of multiple organs was found at necropsy. In this study, disseminated histoplasmosis had a higher prevalence in cats than in dogs at the same veterinary medical teaching hospital. Feline disseminated histoplasmosis was not associated with FeLV infection. Treatment was attempted in 7 of the 12 cats.     

Cryptosporidiosis in neonatal calves: 277 cases (1986-1987)

From January 1986 through December 1987, 277 cases of cryptosporidiosis in calves were diagnosed by the South Dakota State University Diagnostic Laboratory. Cryptosporidium sp was the only pathogen identified in 142 (51.3%) of the calves. Concurrent infections with rotavirus, coronavirus, Escherichia coli, Salmonella sp, bovine viral diarrhea virus, or other pathogens were identified in the remaining 135 calves. After elimination of cases involving autolyzed specimens or calves with chronic diarrhea, records of 11 calves with acute, severe cryptosporidiosis were identified in which Cryptosporidium sp was the only pathogen.     

Canine intracranial primary neoplasia: 173 cases (1986-2003)

This study investigates the clinical and pathologic findings associated with 173 primary brain tumors in our hospital population of dogs that presented between the years 1986 and 2002. Of the 173 primary brain tumors, 78 (45%) were meningiomas, 29 (17%) were astrocytomas, 25 (14%) were oligodendrogliomas, 12 (7%) were choroid plexus tumors, and 7 (4%) were primary central nervous system lymphomas. Smaller numbers of glioblastomas (n = 5), primitive neuroectodermal tumors (n = 5), histiocytic sarcomas (n = 5), vascular hamartomas (n = 4), and unclassified gliomas (n = 3) were identified. One dog had both a meningioma and an astrocytoma. Most tumors were located within the telencephalon, and seizures were the most common clinical presenting complaint. Of 168 tumors for which a location in the brain was recorded at postmortem examination, 79 were found to involve more than 1 brain division. Other neoplasms unrelated to the primary brain tumor were identified on postmortem examination in 39 dogs (23%). Intrathoracic and intraabdominal neoplasms were present at necropsy in 13 and 24 cases, respectively. Based on the results of this study, thoracic radiographs and abdominal ultrasonography may be indicated to look for extracranial neoplasia prior to advanced imaging of the brain or intracranial surgery.