Ultrasonographic characteristics of canine renal lymphoma

Focused Ultrasound Examination of Canine and Feline Emergency Urinary Tract Disorders

This article discusses the usefulness of ultrasound examinations in the management of the patient with an emergency urinary tract disorder. It discusses the use of previously described point-of-care ultrasound protocols such as the abdominal focused assessment with sonography for trauma, triage, and tracking protocol in the unstable azotemic patient. Point-of-care ultrasound examination can help direct investigations and expedite the diagnosis of specific causes of azotemia. The limitations of point-of-care ultrasound assessment of the kidneys, ureter, bladder, and urethra are also addressed, emphasizing that point-of-care ultrasound examination should complement and not replace a complete urinary tract ultrasound examination.

A case of canine renal lymphoma of granular lymphocytes with severe polycythemia

BACKGROUND

Renal lymphoma in dogs is rare and has a poor prognosis. Granular lymphocyte morphology is rarely reported in canine renal lymphoma. Mild to moderate polycythemia is reported in a number of canine renal lymphoma cases.

CASE PRESENTATION

A 10-year-old Labrador retriever presented to a university veterinary teaching hospital after a 1-month history of polyuria, polydipsia, and pollakiuria and a 2-week history of abdominal distention, lethargy, and increased respiratory effort. Abdominal ultrasound showed a wedge-shaped to rounded, heterogeneously hypoechoic mass lesion in the left kidney. Cytologic analysis of a percutaneous aspirate of the mass was consistent with lymphoma of granular lymphocytes. Severe polycythemia (hematocrit 0.871) was noted on a complete blood cell count. Clonality analysis identified a clonally rearranged T-cell receptor (TCR) gene and immunohistochemical staining was CD3+, CD79a- and CD11d+, supporting cytotoxic T-cell lymphoma.

CONCLUSIONS

To our knowledge, this is the first report of renal cytotoxic T-cell lymphoma with severe polycythemia in a dog. Severe polycythemia and renal cytotoxic T-cell lymphoma are both rare in dogs; this report adds to the body of knowledge on these conditions.

Can distinction between the renal cortex and outer medulla on ultrasonography predict estimated glomerular filtration rate in canine chronic kidney diseases?

Background

Quantitative evaluation of renal cortical echogenicity (RCE) has been tried and developed in human and veterinary medicine.

Objectives

The objective of this study was to propose a method for evaluating RCE quantitatively and intuitively, and to determine associations between ultrasonographic renal structural distinction and estimated glomerular filtration rate (eGFR) in canine chronic kidney disease (CKD).

Methods

Data were collected on 63 dogs, including 27 with normal kidney function and 36 CKD patients. Symmetric dimethylarginine and creatinine concentrations were measured for calculating eGFR. RCE was evaluated as 3 grades on ultrasonography images according to the distinction between the renal cortex and outer medulla. The RCE grade of each kidney was measured.

Results

There was a significant difference in eGFR between the group normal and CKD (p < 0.001). As mean of RCE grades (the mean values of each right and left kidney's RCE grade) increases, the proportion of group CKD among the patients in each grade increases (p < 0.001). Also, severity of RCE (classified as "high" if any right or left kidney evaluated as RCE grade 3, "low" otherwise) and eGFR is good indicator for predicting group CKD (p < 0.001).

Conclusions

The degree of distinction between the renal cortex and the outer medulla is closely related to renal function including eGFR and the RCE grade defined in this study can be used as a method of objectively evaluating RCE.

Contrast-enhanced computed tomography findings of canine primary renal tumors including renal cell carcinoma, lymphoma, and hemangiosarcoma

In veterinary medicine, abdominal ultrasonography is used to rank the differential diagnosis of renal lesions. However, a conventional sonographic examination may show nonspecific findings. The purpose of this study was to assess the computed tomography (CT) findings of canine renal tumors, including renal cell carcinoma (RCC), lymphoma, and hemangiosarcoma (HSA). In this retrospective study, the following CT parameters were recorded for each dog: 1) extent of renal involvement of tumors, 2) enhancement pattern, 3) number of renal tumors, 4) renal tumor vessel enhancement in the corticomedullary phase, 5) presence of lymphadenopathy and lung metastasis, and 6) attenuation values of the renal tumors on the pre- and post-contrast corticomedullary, nephrographic, and excretory phase images. Fifteen dogs met the inclusion criteria, of which nine had RCCs, four had lymphomas, and two had HSAs. RCCs tended to show heterogeneous enhancement and unilateral renal involvement, and vessel enhancement was detected in the corticomedullary phase in dogs with RCC. Conversely, renal lymphomas showed homogeneous enhancement, bilateral renal involvement, and multiple masses; in these dogs, no vessel enhancement was detected in the corticomedullary phase, and the incidence of lymphadenopathy was low. However, in dogs with lymphadenopathy, the renal lymphoma was associated with regionally severe lymphadenopathy. Finally, renal HSAs tended to show heterogeneous enhancement with a non-enhanced area and unilateral renal involvement; in these dogs, vessel enhancement was detected in the nephrographic phase, with the enhancement expanding around the vessel. These findings had no significant differences. Further studies with a larger sample size are required to examine the association between CT and histopathological findings.

Clinical characteristics and outcome of dogs with presumed primary renal lymphoma

OBJECTIVES

To characterise the presentation, clinicopathologic data and outcome of 29 dogs with presumed primary renal lymphoma.

MATERIALS AND METHODS

Retrospective analysis of medical records of dogs with suspected primary renal lymphoma from 11 institutions.

RESULTS

All dogs were substage b, and lethargy and gastrointestinal signs were common presenting complaints, as were azotaemia (n=25; 86%) and erythrocytosis (n=15; 51%) on biochemical testing. Ultrasonography typically revealed bilateral renal lesions (n=23; 79%), renomegaly (n=22; 76%) and abdominal lymphadenopathy (n=14; 48%). Chemotherapy was the only treatment in 23 dogs, of which 11 responded, all considered partial responses. For all dogs the median progression-free survival and median overall survival times were 10 days (range: 1 to 126) and 12 days (range: 1 to 212), respectively, and for dogs that responded to chemotherapy 41 days (range: 10 to 126) and 47 days (range: 10 to 212), respectively.

CLINICAL SIGNIFICANCE

Primary renal lymphoma in dogs appears to be associated with a poor prognosis and short-lived response to chemotherapy.

Ultrasonographic findings in cats with acute kidney injury: a retrospective study

OBJECTIVES

The aims of the study were to identify the ultrasonographic findings in cats with acute kidney injury (AKI) and to assess whether they had prognostic value.

METHODS

This was a descriptive case series. A search of the computerised records of the Queen Mother Hospital for Animals (Hatfield, UK) was performed for cats presenting with AKI between 2007 and 2016. Patients were excluded if they had historical data consistent with chronic kidney disease. Ultrasound images were reviewed for the presence of six renal ultrasonographic abnormalities: nephromegaly, cortical and medullary echogenicity, pyelectasia, and retroperitoneal and peritoneal fluid. Ultrasonographic findings were assessed individually and cumulatively to give an ultrasound score out of 6. Ultrasonographic findings were assessed for association with oligouria/anuria and survival.

RESULTS

Forty-five cats with AKI fulfilled the inclusion criteria. In total, 6.7% (3/45) of cats had normal renal size and architecture. The most common renal ultrasonographic findings were nephromegaly, pyelectasia and increased renal echogenicity. The presence of retroperitoneal fluid was associated with oligouria/anuria. Total ultrasound score (out of 6) was significantly associated with oligouria/anuria and 6 month survival.

CONCLUSIONS AND RELEVANCE

Ultrasonographic findings are common in cats presenting with AKI. The increasing number of renal ultrasonographic abnormalities and the presence of retroperitoneal fluid alone are associated with oligouria/anuria and a higher ultrasound score may suggest a poorer long-term prognosis.

Urinary Tract Cytology

Cytologic evaluation of the urinary tract can be diagnostically rewarding in cases of renomegaly or when discrete kidney or bladder masses are identified. Cytology can often help to distinguish between cystic, inflammatory, and neoplastic disorders. Various types of cystic and benign urinary tract lesions, diseases associated with urinary tract inflammation, and the cytologic differences between primary and metastatic neoplasms of the kidney and bladder are described. Basic sampling techniques for urinary tract cytology are also discussed.

Predominance of hypoechoic tissue changes in nine dogs with malignant prostatic lymphoma

Neoplasia of the prostate is relatively uncommon in dogs with adenocarcinoma being the most common type. Non-epithelial tumors are rare and only individual cases of malignant lymphoma affecting the prostate have been reported. The purpose of this multi-institutional, retrospective, descriptive study was to characterize the ultrasonographic features of canine prostatic lymphoma. Inclusion criteria were an abdominal ultrasound and cytological/histological diagnosis of malignant prostatic lymphoma. Ultrasonographic features were recorded based on the original ultrasonographic reports and consensus opinion of two readers on the available image sets retrospectively. Nine dogs met the inclusion criteria with a mean age of 6.5 years. Seven dogs were intact and two neutered. Subjective prostatomegaly was noted in all patients however not reproducible by objective measurements. Altered shape with rounded/irregular margins was detected in 78% of the cases. All prostates presented either diffuse (three dogs) or focal/periurethral (four dogs) and/or multifocal areas of hypoechogenicity (three dogs). In one dog, focal and multifocal hypoechoic changes co-occurred. Prostatic mineralization was not present in any of the cases. Ultrasonographic features of infiltrative disease of multiple organs and/or lymphadenopathy was found in all cases. Even though malignant lymphoma is rare in the prostate, it should be included in the list of differentials in patients with hypoechoic lesions/areas, altered shape, lack of mineralization of the prostatic parenchyma and evidence of multiorgan involvement.

Evaluation of the diagnostic utility of cytologic examination of renal fine-needle aspirates from dogs and the use of ultrasonographic features to inform cytologic diagnosis

OBJECTIVE To describe cytologic characteristics of renal fine-needle aspirate (FNA) samples from dogs, evaluate proportions of cytologic specimens deemed adequate for interpretation (diagnostic yield), assess diagnostic utility of cytologic examination for neoplastic and nonneoplastic diseases, and characterize ultrasonographic features of evaluated kidneys to determine whether the imaging characteristics could be used to inform cytologic interpretations. DESIGN Retrospective, observational study. SAMPLE 102 cytologic specimens and 97 ultrasonographic studies from 100 dogs. PROCEDURES Medical records were reviewed to identify dogs that underwent ultrasound-guided renal FNA. Slides were categorized as adequate or inadequate for interpretation; adequate slides were used for retrospective cytologic diagnosis. Sensitivity, specificity, and predictive values of cytologic examination for detection of neoplastic and nonneoplastic conditions were calculated by comparison with histologic or lymphoid cell clonality assay results. Ultrasonographic characteristics of neoplastic and nonneoplastic renal lesions were described. RESULTS 74 of 102 (72%) specimens had slides adequate for interpretation; 26 were included in the diagnostic accuracy analysis. Sensitivity of cytologic examination was 78% and 50% for detection of neoplastic and nonneoplastic conditions, respectively, with specificities of 50% and 77%, respectively; sensitivity for detection of lymphoma was 100%. Ultrasonographic appearance of kidneys with confirmed neoplasia varied; masses were most commonly found in kidneys with carcinoma (5/5), lymphoma (5/7), or other neoplasia (3/4) and absent in kidneys with nonneoplastic conditions (n = 5). CONCLUSIONS AND CLINICAL RELEVANCE Renal FNA specimens were adequate for interpretation at rates comparable with those reported for other organs and were considered clinically useful for diagnosis of neoplasia. Imaging characteristics may potentially aid differentiation between neoplastic and nonneoplastic lesions; however, further investigation is needed.

Uterine B-cell lymphoma in two dogs – a case report

Uterine lymphoma is rare in the dog, in other animal species, and in humans. The lymphoma in the two female dogs presented as a primary tumour of uterine tissue and was classified as diffuse centroblastic B cell lymphoma. Terminally, the uterine lymphoma metastasized to various organs in one of the dogs, despite chemotherapy. This case study describes a very rare form of canine lymphoma and suggests to include lymphoma in the differential diagnoses in bitches with uterine masses.