In a 10-year retrospective study, we evaluated the clinicopathologic features and renal immunofluorescence patterns of
glomerulonephritis in 41 dogs. On the basis of results of histologic examinations, the dogs were segregated into 3 groups, including membranous (n = 12), mesangioproliferative (n = 15), or
membranoproliferative glomerulonephritis (n = 14). No significant differences existed among groups in regard to age or duration of illness. Most dogs had been ill for one month or longer. The proportion of dogs with
azotemia,
anemia, and
hyperphosphatemia were not different among the disease groups. Proportion of dogs with
hypoalbuminemia and the severity of
hypoalbuminemia were not different among groups. Highest urine
protein losses and 24-hour urine
protein/
creatinine ratios developed in dogs with
membranous glomerulonephritis. Although
hypoalbuminemia and
hypercholesterolemia were common (49%), the formation of
edema or
ascites was not (15%) and, therefore, few dogs had all of the classic features of the
nephrotic syndrome. Few dogs suffered thromboembolic complications.
Antinuclear antibody titers developed in 11 dogs, the highest titers developing in dogs with
polyarthritis and systemic lupus erythematosis.
Cellulose acetate electrophoresis detected alpha 2 and beta 1
globulin spikes in most dogs (87%). Results of renal immunofluorescence testing were positive in 36 dogs, using polyvalent
antisera for
immunoglobulins (Ig)G,
IgA,
IgM, and/or
antisera for
complement factor C3. When monovalent
antisera for
IgG,
IgA, and
IgM, and
fibrinogen were used, immunofluorescence was not observed as often. The major fluorescent pattern was discrete multifocal segmental granular glomerular fluorescence, consistent with
immune-complex deposition. Two dogs had linear glomerular staining patterns; however,
antibodies directed against normal glomerular basement membrane were not found via elution studies. A high prevalence of
glucocorticoid excess (treatment with
glucocorticoids and spontaneous
hyperadrenocorticism) (34%), chronic inflammatory
skin disease (27%),
neoplasia (17%),
polyarthritis (12%), and systemic lupus erythematosis (7%) were observed as clinical problems concurrent with
glomerulonephritis. In 5 dogs, treatment of
glomerulonephritis with
prednisolone (0.5 to 1.1 mg/kg) did not result in beneficial effects and in fact appeared to be detrimental, leading to
azotemia and worsening
proteinuria and physical condition in some of the dogs.(ABSTRACT TRUNCATED AT 400 WORDS)