Renal Pathology Consultation Service

Posted by: Cathy Brown, VMD, PhD, DACVP and Scott A. Brown, VMD, PhD, DACVIM

Kidney disease is a leading cause of illness and death in dogs and cats. Treatment of acute and chronic kidney disease is most effective when the disease is recognized early in its course and when treatment is instituted with knowledge of the underlying disease process. To aid in the diagnosis and treatment of kidney disease, the Athens Veterinary Diagnostic Laboratory is now offering renal diagnostic and treatment expertise through its newly established Renal Pathology Consultation Service. The service is provided under the direction of Dr. Cathy Brown, a board certified veterinary pathologist, who is an internationally recognized expert in renal pathology. She is a member of the World Small Animal Veterinary Association’s Renal Standardization group. She has authored or co-authored multiple book chapters on evaluation of the renal biopsy and numerous publications characterizing renal disease. Dr. Scott Brown, a board certified small animal internist, is also a member of the Renal Pathology Consultation Service. He was the founding chairman of the International Renal Interest Society (IRIS) and led the establishment of the IRIS kidney disease staging system.

The primary focus of the Renal Pathology Consultation Service will be to provide detailed pathologic and consultative service to veterinarians submitting renal biopsies. In addition to providing disease diagnosis and prognostic information by a pathologist specializing in kidney diseases, the pathology results will be reviewed by a veterinary clinical nephrologist. Clinical information, including clinical history, treatments, clinical pathology data (including urine protein/creatinine ratio) will be reviewed in the context of the pathologic findings to render a clinical assessment and suggest further diagnostic and treatment options.

Renal biopsy is most useful in dogs and cats with persistent proteinuria (with or without azotemia) or in animals with acute renal disease that is not responding as expected or in which an etiologic diagnosis may be needed. Biopsies from animals with advanced chronic kidney disease (IRIS Stages III and IV), particularly those with irregular scarred kidneys, are generally not useful as the renal damage is irreversible and the information obtained is unlikely to change treatment strategies. Renal biopsies submitted to the Renal Pathology Consultation Service will be evaluated by a veterinary nephropathologist via light microscopy using a battery of stains. Biopsies from animals with protein-losing nephropathy will also be examined via electron microscopy (EM) to evaluate ultrastructural morphology,

Biopsies (wedge or needle biopsies) for light microscopy should be submitted in 10% formalin. Care should be taken when handling needle biopsies to limit crush artifact. If protein-losing glomerular disease has been identified, an additional cortical biopsy should be minced, using a scalpel blade, into 1 mm squares and submitted in EM fixative (glutaraldehyde). Vials of EM fixative are available from the diagnostic laboratory, and should be obtained prior to the biopsy procedure.

Our goal is to increase the quality of our diagnostic service and case management for animals with kidney disease. If you have questions about our new Renal Pathology Consultation Service, please contact Dr. Cathy Brown at 706.542.5568.