Search Results

Abstract

Objective—To characterize interstitial lung diseases (ILDs) and evaluate use of keyhole lung biopsy for diagnosis of ILDs in dogs and cats.

Design—Retrospective study.

Animals—11 dogs and 2 cats.

Procedure—Medical records of dogs and cats undergoing keyhole lung biopsy to confirm ILDs were reviewed. Signalment, clinical signs, results of thoracic radiography and other respiratory diagnostic tests, postoperative complications, and patient outcome were analyzed.

Results—Clinical respiratory signs included cough, tachypnea, exercise intolerance, and hemoptysis. Thoracic radiographic abnormalities included interstitial, alveolar, and bronchointerstitial patterns and multiple discrete pulmonary nodules. Lung biopsy and histologic examination revealed interstitial pulmonary fibrosis, bronchiolitis obliterans with organizing pneumonia, or unclassified lesions. Outcome after biopsy included no response to treatment, euthanasia, partial or complete remission while receiving medication, and cure.

Conclusions and Clinical Relevance—Recognition and classification of ILDs in dogs and cats are likely to be important in guiding appropriate treatment and providing accurate prognostic information. Ancillary respiratory diagnostic tests are beneficial in ruling out infectious and neoplastic disorders that may mimic ILDs; however, their present use in the diagnosis of ILDs is limited. Results suggest that keyhole lung biopsy is an effective means for obtaining a specimen for histologic diagnosis in dogs and cats with ILDs. ( J Am Vet Med Assoc 2002;221:1453–1459)

Abstract

Objective—To determine clinical signs, radiographic and histologic abnormalities, and concurrent diseases in cats with endogenous lipid pneumonia (EnLP) and to determine the pathologic importance of EnLP in cats.

Design—Retrospective study.

Animals—24 cats.

Procedure—Medical records of cats in which EnLP was confirmed by histologic examination of necropsy specimens were reviewed. Information collected from the medical records included signalment, body weight, clinical signs, and results of clinicopathologic tests. Thoracic radiographs were reviewed by a radiologist; histologic specimens were reviewed by a pathologist.

Results—All cats had nonspecific clinical abnormalities, such as lethargy, anorexia, or weight loss; 16 had signs of respiratory tract disease. All cats had concurrent systemic diseases, and clinicopathologic abnormalities were reflective of these conditions. Nonspecific abnormalities were detected on thoracic radiographs from 9 of 11 cats. Most cats had macroscopic, multifocal, subpleural lesions; inflammatory infiltrates, cholesterol clefts, and multinucleated giant cells were common. Ten cats had an underlying obstructive pulmonary disease that was the likely cause of EnLP. Lesions of EnLP were not considered to be severe enough or extensive enough to be the cause of death in any of these cats.

Conclusion and Clinical Relevance—EnLP is an uncommon respiratory tract disorder of cats with no pathognomonic clinical, laboratory, or radiographic findings. Although EnLP was not the cause of death in any of these cats, results of the present study do suggest that EnLP may be a marker for potentially severe underlying obstructive pulmonary disease. (J Am Vet Med Assoc 2000;216:1437–1440)

Abstract

Objective—To investigate the effects of preexisting FeLV infection or FeLV and feline immunodeficiency (FIV) coinfection on the pathogenicity of the small variant of Haemobartonella felis (Hfsm, California variant) in cats.

Animals—20 FeLV infected, 5 FeLV-FIV coinfected, and 19 retrovirus-free cats.

Procedure—A client-owned cat, coinfected with FeLV and Hfsm, was the source for Hfsm. Inoculum 1 (FeLV free) was obtained by passage of source Hfsm through 4 FeLV-resistant cats. Inoculum 2 was obtained by further passage of Hfsm (inoculum 1) through 2 specific pathogenfree cats.

Results—A mild-to-moderate anemia started 21 days after inoculation, with its nadir occurring at 35 to 42 days after inoculation. Infection with Hfsm induced greater decrease in hemoglobin concentration in FeLV infected cats, compared with retrovirus free cats. Reticulocytosis, macrocytosis, and polychromasia of erythrocytes developed in anemic cats regardless of retrovirus infection status. Mean neutrophil counts decreased during the hemolytic episode. For most cats, the anemia was transient. Four FeLV infected cats, 1 of which was also FIV infected, developed fatal FeLV-associated myeloproliferative diseases. Of the surviving cats, 8 died over the next 24 months from other FeLV-related diseases. Hemolysis did not recur after the initial episode. Inoculum 1 induced more severe anemia than inoculum 2.

Conclusions and Clinical Relevance—Our results support the clinical observation that cats coinfected with FeLV and H felis develop more severe anemia than cats infected with H felis alone. Infection with Hfsm may induce myeloproliferative disease in FeLV infected cats. The small variant of H felis may lose pathogenicity by passage through FeLV-free cats. (Am J Vet Res 2002;63:1172–1178)

Abstract

Objective—To determine clinicopathologic and radiographic features and etiologic agents in cats that died as a result of infectious pneumonia.

Design—Retrospective study.

Animals—39 cats.

Procedure—Medical records of cats in which infectious pneumonia was confirmed by histologic examination of necropsy specimens were reviewed. Signalment, clinical signs, and results of a CBC, viral serologic tests, and thoracic radiography were evaluated. Infectious agents were classified as bacterial, viral, fungal, protozoal, or parasitic. Histologic features (severity, duration, anatomic location, and distribution) were analyzed.

Results—Clinical signs referable to the respiratory tract were not detected in 14 of 39 (36%) cats, and results of a CBC (4/18 cats) and radiography (3/13) were unremarkable. Sixteen of 39 (41%) cats lacked clinical signs of systemic illness. Etiologic agents identified included bacteria (n = 21), viruses (11), fungi (6), protozoa (2), and parasites (1). Cats with clinical signs related to the respiratory tract (19/24 [79%] cats) were more likely to have severe histologic changes than cats without signs related to the respiratory system (6/14). Twenty-nine of 38 (76%) cats had histologic evidence of systemic disease, whereas the remaining cats had lesions limited to the respiratory tract.

Conclusions and Clinical Relevance—Infectious pneumonia is uncommon in cats. Cats with infectious pneumonia may lack clinical signs and have unremarkable results for a CBC and thoracic radiography, yet frequently have systemic infections. Therefore, clinicians should maintain an index of suspicion for pneumonia and evaluate the respiratory tract when infection is detected in other organ systems. (J Am Vet Med Assoc 2003;223:1142–1150)

Abstract

Objective—To determine cytologic and microbiologic findings in bronchoalveolar lavage (BAL) fluid and SpO ₂ values obtained during BAL in healthy rabbits.

Animals—9 rabbits.

Procedures—Bronchoscopic BAL of left and right caudal lobar bronchi (LB2 and RB4) was performed with 3 mL of sterile saline (0.9% NaCl) solution; SpO ₂ was measured before, during, and after BAL. Percentage fluid recovered, total leukocyte counts, and differential cell counts were determined. Aerobic and anaerobic bacterial, mycoplasmal, and fungal cultures were performed from combined LB2 and RB4 samples.

Results—Mean ± SD percentage fluid volumes recovered from LB2 and RB4 were 53 ± 13% and 63 ± 13%, respectively. Mean ± SD total leukocyte counts from LB2 and RB4 were 422 ± 199 cells/μL and 378 ± 97 cells/μL, respectively. Macrophages were most frequently identified. There were no significant differences in volumes retrieved, total leukocyte counts, or differential cell percentages between LB2 and RB4. Microbial culture results were negative for 3 rabbits and positive for mixed aerobic and anaerobic bacterial growth in 6 and 2 rabbits, respectively. The SpO ₂ was ≥ 95% in 7 of 9 rabbits after anesthetic induction, < 95% in 5 of 6 rabbits 1 minute after BAL, and ≥ 95% in 5 of 9 rabbits and > 90% in 4 of 9 rabbits 3 minutes after BAL.

Conclusions and Clinical Relevance—Bronchoscopic BAL with 3 mL of saline solution provided adequate fluid recovery for microbiologic and cytologic examination from the caudal lung lobes. Transient low SpO ₂ was detected immediately after BAL.

Abstract

Objective—To describe pharmacokinetics of multidose oral administration of tacrolimus in healthy cats and evaluate the efficacy of tacrolimus in the prevention of allograft rejection in cats with renal transplants.

Animals—6 healthy research cats.

Procedure—Cats received tacrolimus (0.375 mg/kg, PO, q 12 h) for 14 days. Blood tacrolimus concentrations were measured by a high performance liquid chromatography-mass spectrometry assay. Each cat received an immunogenically mismatched renal allograft and native kidney nephrectomy. Tacrolimus dosage was modified to maintain a target blood concentration of 5 to 10 ng/mL. Cats were euthanatized if plasma creatinine concentration exceeded 7 mg/dL, body weight loss exceeded 20%, or on day 50 after surgery. Kaplan-Meier survival curves were plotted for 6 cats treated with tacrolimus and for 8 cats with renal transplants that did not receive immunosuppressive treatment.

Results—Mean (± SD) values of elimination half-life, time to maximum concentration, maximum blood concentration, and area under the concentration versus time curve from the last dose of tacrolimus to 12 hours later were 20.5 ± 9.8 hours, 0.77 ± 0.37 hours, 27.5 ± 31.8 ng/mL, and 161 ± 168 hours × ng/mL, respectively. Tacrolimus treated cats survived longer (median, 44 days; range, 24 to 52 days) than untreated cats (median, 23 days; range, 8 to 34 days). On histologic evaluation, 3 cats had evidence of acute-active rejection, 1 cat had necrotizing vasculitis, and 2 cats euthanatized at study termination had normal appearing allografts.

Conclusions and Clinical Relevance—Tacrolimus may be an effective immunosuppressive agent for renal transplantation in cats. (Am J Vet Res 2003;64:926–934)

Abstract

Objective—To develop a computer-assisted image analysis procedure for quantitation of neovascularization in formalin-fixed paraffin-embedded specimens of thyroid gland tissue from dogs with and without thyroid gland neoplasia.

Sample Population—47 thyroid gland carcinomas, 8 thyroid gland adenomas, and 8 specimens of thyroid tissue from dogs without thyroid gland abnormalities (normal).

Procedure—Serial tissue sections were prepared and stained with antibodies against human CD31 or factor VIII-related antigen (factor VIII-rag). The areas of highest vascularity were identified in CD31- stained sections, and corresponding areas were then identified in factor VIII-rag-stained sections. Image analysis was used to calculate the total vascular density in each section, and neovascularization, expressed as a percentage, was determined as the absolute value of the total vascular density derived from factor VIII-rag-stained sections minus the vascular density derived from CD31-stained sections.

Results—Mean vascular density of thyroid gland carcinomas derived from CD31-stained sections was significantly greater than density derived from factor VIII-rag-stained sections. This incremental difference was presumed to represent degree of neovascularization. However, significant differences were not detected between vascular densities derived from CD31 and factor VIII-rag-stained sections for either normal thyroid gland tissue or thyroid gland adenomas. No significant correlations were found between vascular density in thyroid gland carcinomas and survival time following surgery.

Conclusion and Clinical Relevance—A computerassisted image analysis method was developed for quantifying neovascularization in thyroid gland tumors of dogs. This method may allow identification of dogs with tumors that are most likely to respond to treatment with novel antiangiogenesis agents. (Am J Vet Res 2002;63:363–369)

Abstract

Objective—To determine the incidence of bovine papillomavirus (BPV) type 1 or 2 in sarcoids and other samples of cutaneous tissues collected from horses in the western United States.

Animals—55 horses with sarcoids and 12 horses without sarcoids.

Procedure—Tissue samples (tumor and normal skin from horses with sarcoids and normal skin, papillomas, and nonsarcoid cutaneous neoplasms from horses without sarcoids) were collected. Tissue samples were analyzed for BPV-1 or -2 DNA, using a polymerase chain reaction (PCR) and restriction fragment length polymorphism. The PCR products from 7 sarcoid- affected horses were sequenced to evaluate percentage homology with expected sequences for BPV-1 or -2.

Results—Most (94/96, 98%) sarcoids contained BPV DNA. Sixty-two percent of the tumors examined had restriction enzyme patterns consistent with BPV-2. Thirty-one of 49 (63%) samples of normal skin obtained from horses with sarcoids contained BPV DNA. All samples subsequently sequenced had 100% homology with the expected sequences for the specific viral type. All tissues from healthy horses, nonsarcoid neoplasms, and papillomas were negative for BPV DNA.

Conclusions and Clinical Relevance—Bovine papillomaviral DNA was detected in essentially all sarcoids examined. There appears to be regional variation in the prevalence of viral types in these tumors. The fact that we detected viral DNA in normal skin samples from horses with sarcoids suggests the possibility of a latent viral phase. Viral latency may be 1 explanation for the high rate of recurrence following surgical excision of sarcoids. (Am J Vet Res 2001;62:741–744)

Abstract

Objective—To assess the influence of tumor cell proliferation and sex-hormone receptors on the efficacy of megavoltage irradiation for dogs with incompletely resected meningiomas.

Design—Longitudinal clinical trial.

Animals—20 dogs with incompletely resected intracranial meningiomas.

Procedure—Dogs were treated with 48 Gy of radiation administered 3 times per week on an alternateday schedule of 4 Gy/fraction for 4 weeks, using bilateral parallel-opposed fields.

Results—Tumor proliferative fraction measured by immunohistochemical detection of proliferating cell nuclear antigen (PFPCNA index) ranged from 10 to 42% (median, 24%). Progesterone receptor immunoreactivity was detected in 70% of tumors. Estrogen receptor immunoreactivity was not detected. An inverse correlation was found between detection of progesterone receptors and the PFPCNA index. The overall 2-year progression-free survival (PFS) rate was 68%. The only prognostic factor that significantly affected PFS rate was the PFPCNA index. The 2-year PFS was 42% for tumors with a high PFPCNA index (value ≥ 24%) and 91% for tumors with a low PFPCNA index (value < 24%). Tumors with a high PFPCNA index were 9.1 times as likely to recur as were tumors with a low PFPCNA index.

Conclusions and Clinical Relevance—This study confirms the value of irradiation for dogs with incompletely resected meningiomas. Prognostic value of the PFPCNA index suggests that duration of treatment and interval from surgery to start of irradiation may affect outcome. Loss of progesterone receptors in some tumors may be responsible for an increase in PFPCNA index and may indirectly affect prognosis after radiation therapy. (J Am Vet Med Assoc 2000;216: 701–707)

Abstract

Objective—To determine whether histopathologic changes are detectable in grossly normal medial menisci from dogs with rupture of the cranial cruciate ligament (CCL).

Design—Case series.

Sample Population—40 medial menisci from dogs with rupture of the CCL and 20 medial menisci from control dogs without stifle joint disease.

Procedure—Data evaluated included age, duration of clinical signs, and whether rupture of the CCL was complete or incomplete. Three groups (n = 20/group) were also compared on the basis of 5 histologic criteria; group-1 menisci appeared grossly normal and were obtained from dogs with naturally occurring rupture of the CCL, group-2 menisci were grossly abnormal and were also obtained from dogs with naturally occurring CCL ruptures, and group-3 menisci were collected at postmortem from dogs without stifle joint disease that were of similar age and weight as dogs in groups 1 and 2.

Results—Group-2 menisci were significantly different from group-1 and -3 menisci in all histologic criteria. Group-1 menisci were significantly different from control menisci in only 1 of the 5 histologic criteria (cartilage differentiation). Dogs that were ≥ 3 years old had significantly more surface cellularity than did dogs that were < 3 years old. A significant difference was not detected between groups 1 and 2 with regard to completeness of rupture.

Conclusions and Clinical Relevance—Histologic changes in meniscal cartilage correlate with gross appearance of the cartilage at time of surgery for rupture of the CCL. On the basis of minimal histologic changes, routine removal of grossly normal menisci does not appear to be warranted. (J Am Vet Med Assoc 2001;218:1281–1284)