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Glomerular Disease
Shelly L. Vaden, DVM, PhD, DACVIM (SAIM)

College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA

Etiology/Pathophysiology glomerular disease have undergone renal damage second-
ary to a disorder occurring elsewhere in the body. A NIN
Glomerular disease is a leading cause of renal disease in disorder may not be obvious at first presentation because
dogs but appears to be less common in cats. Accordingly, it is either resolved or occult. Because occult NIN disor-
most of the content of this chapter is in reference to dogs. ders may become overt months after initial presentation
Historically, glomerular diseases have been classified for proteinuria, continued observation and scrutiny of the
as being either primary or secondary. Primary glomeru- dog and cat with glomerular disease are necessary.
lar diseases arise in the kidney and secondary diseases Familial glomerulopathies have been reported in sev-
occur when the glomeruli are injured as part of a sys- eral breeds of dogs and can cross most of the before
temic disorder. Secondary glomerular injury is generally mentioned categories (Table 121.1).
the result of damage that is either sustained following Hereditary nephritis is the result of defective collagen
immune complex deposition (e.g., membranous glomer- synthesis and has been reported in bull terriers, English
ulonephritis, membranoproliferative glomerulonephri- cocker spaniels, Dalmatians, Samoyed, and mixed breed
tis, proliferative glomerulonephritis) or due to systemic dogs. An inherited podocytopathy is the cause of familial
factors affecting the glomeruli (e.g., amyloidosis, focal protein‐losing nephropathy of soft‐coated wheaten terriers.
segmental glomerulosclerosis, minimal change disease). Shar‐peis develop familial renal amyloidosis following epi-
Recently, an alternative approach to classification has sodes of recurrent fever and swollen joints. The etiopatho-
been suggested in veterinary medicine where, on the basis genesis of many of the remaining disorders is unknown.
of renal biopsy evaluation, three broad categories of dis-
ease are used: amyloidosis, immune complex‐mediated
glomerulonephritis (ICGN), and non‐ICGN. This system Signalment
should greatly facilitate the clinical management of dogs
and cats with glomerular disease by separating out those Glomerular diseases can develop at any age but may be
that might benefit the most from a thorough search for a more common in middle‐aged to older dogs. The
systemic disorder and therapy with immunosuppressive reported average from 876 dogs in six different studies
drugs. In a study of renal biopsies from 501 dogs with glo- was 7.4 years of age. In general, male and female dogs are
merular disease, 48% had ICGN and 15% had amyloido- nearly equally represented among dogs with glomerular
sis, leaving 37% with a variety of non‐ICGN. disease. The average age and gender predilection seen
Because of the strong association between glomerular with specific glomerular diseases will vary somewhat
injury and immune complex deposition or systemic from the overall averages.
inflammation, glomerular diseases are often linked to sys- Any breed can be affected by glomerular disease.
temic disease processes – specifically neoplastic, infec- However, Labrador retrievers, golden retrievers, and
tious, or noninfectious inflammatory (NIN) disorders. Yorkshire terriers may be predisposed based on reported
Published studies have suggested that approximately 50% higher incidence of glomerular disease in these breeds;
of dogs with glomerular disease have an identifiable NIN. however, it is also possible that this increased representation
The categorization of biopsies from the previously men- reflects the popularity of these breeds. Amyloidosis may be
tioned 501 dogs suggests that as many as 63% of dogs with overrepresented in Chinese shar‐peis and English bulldogs.

Clinical Small Animal Internal Medicine Volume II, First Edition. Edited by David S. Bruyette.
© 2020 John Wiley & Sons, Inc. Published 2020 by John Wiley & Sons, Inc.
Companion website: www.wiley.com/go/bruyette/clinical