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390 Glomerulonephritis

Glomerulonephritis Client Education
Sheet
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• Chronic kidney disease (CKD)
BASIC INFORMATION
produced, resulting in secondary immune
• Systemic hypertension provide the antigen to which antibody is
Definition • Hyperlipidemia complex formation.
Glomerulonephritis (GN) is a common kidney • Thromboembolic disease, including pulmo- • Glomerular immune complexes initiate
disorder characterized by proteinuria due to nary thromboembolism an inflammatory cascade that damages
immune complex deposition in the glomeruli • Sideroblastic anemia the glomerulus, neutralizes glomerular
and resultant inflammation. The condition Clinical Presentation endothelial electrical charge, and causes
is often idiopathic, but it can result from vasoconstriction and decreased glomerular
inflammatory, infectious, or neoplastic disease DISEASE FORMS/SUBTYPES filtration. The glomerulus responds to these
processes. Morphologic classification: histopathologic insults with cellular proliferation.
(correlates to therapy and prognosis not as well • Albumin and similarly sized proteins are lost
Epidemiology developed as in human nephrology) in urine and may result in hypoalbuminemia
SPECIES, AGE, SEX • Membranoproliferative GN: common and the nephrotic syndrome. Eventually,
Dogs > cats, with no sex predisposition; any ○ Type I: mesangiocapillary GN associated tubular function is lost as well, resulting in
age, but most are middle-aged or older with infectious disease; most common type azotemia and uremia.
○ Type II: dense deposit disease
GENETICS, BREED PREDISPOSITION • Proliferative GN: rare DIAGNOSIS
Membranoproliferative GN:
• Bernese mountain dogs HISTORY, CHIEF COMPLAINT Diagnostic Overview
• Labrador retrievers, golden retrievers, and Clinical signs may be absent. When signs The diagnosis is suspected based on the identifi-
Shetland sheepdogs with positive Borrelia are present, they may be due to uremia (p. cation of proteinuria, an elevated urine protein/
titers 169), nephrotic syndrome (p. 691), or to the creatinine (UPC) ratio, and characteristic blood
• Brittany spaniel (complement deficiency) underlying disease responsible for GN: and imaging findings. Confirmation requires
Proliferative and sclerosing GN: • Vomiting (uremia or underlying disease) renal biopsy.
• Soft-coated Wheaten terrier • Lethargy (uremia or underlying disease)
• Anorexia (uremia or underlying disease) Differential Diagnosis
RISK FACTORS • Weight loss (uremia, proteinuria, or underly- Proteinuria:
• Chronic bacterial infections (e.g., pyoderma, ing disease) • Preglomerular (e.g., Bence Jones proteinuria,
endocarditis, pyelonephritis, borreliosis, • Peripheral edema (hypoalbuminemia) exercise, hemolysis, fever, seizure)
mycoplasmal polyarthritis) • Pendulous abdomen/ascites (hypoalbuminemia) • Renal (glomerular causes of proteinuria
• Fungal infection (e.g., coccidioidomycosis) • Polyuria/polydipsia (CKD) typically result in greater proteinuria than
• Parasitic (e.g., heartworm disease) • Halitosis (uremia) nonglomerular causes)
• Rickettsial disease (e.g., ehrlichiosis) • Dyspnea/panting (pulmonary thromboem- ○ GN
• Protozoal infection (e.g., babesiosis, hepa- bolism, ascites) ○ Amyloidosis
tozoonosis, leishmaniasis) • Blindness (systemic hypertension) ○ Glomerulosclerosis, including CKD
• Viral disease (e.g., feline immunodefi- • Signs associated with underlying infectious, ○ Familial glomerulonephropathy
ciency virus, feline leukemia virus, canine inflammatory, or neoplastic disease ○ Tubular
adenovirus) ○ Interstitial nephritis
• Neoplasia (e.g., mastocytosis, lymphoma, PHYSICAL EXAM FINDINGS • Postglomerular (e.g., urinary tract infection,
systemic histiocytosis) Clinical findings may be absent or may include neoplasia, urolithiasis)
• Immune-mediated disease (e.g., polyarthritis, • Poor body condition
systemic lupus erythematosus) • Dehydration Initial Database
• Chronic inflammatory disease (e.g., • Poor haircoat • Retinal exam: tortuous retinal vessels,
inflammatory bowel disease, pancreatitis, • Signs associated with hypoalbuminemia retinal hemorrhages (acute or chronic), or
cholangiohepatitis, thyroiditis) ○ Peripheral edema retinal detachments can result from systemic
• Glucocorticoid excess ○ Ascites (pure transudate) hypertension.
• Trimethoprim-sulfadiazine therapy ○ Pleural effusion (rare) • Blood pressure: systemic hypertension
• Congenital C3 (complement) deficiency • Signs associated with uremia (repeatable systolic readings > 180 mm Hg
• Genetic predisposition ○ Oral ulceration in calm environment) is common (pp. 501
See further discussion on p. 1226. ○ Halitosis (uremia) and 1065).
• Pallor (due to anemia or poor perfusion if • CBC: often unremarkable; nonregenerative
CONTAGION AND ZOONOSIS severe illness) anemia (of chronic disease or due to CKD),
Some causes of secondary GN are zoonotic • Lipid corneal deposits leukocytosis (if inflammatory disease is
(e.g., leptospirosis, leishmaniasis). • Retinal hemorrhage/detachment (systemic present)
hypertension) • Serum biochemical profile
GEOGRAPHY AND SEASONALITY • Kidneys may be normal sized or small. ○ Hypoalbuminemia with normal or
Several causes of secondary GN have specific • Other findings related to underlying increased globulin level
geographic distributions (e.g., borreliosis in disease ○ Hypercholesterolemia
northeastern and north central United States). ○ Hypocalcemia (relative, due to hypoalbu-
Etiology and Pathophysiology minemia)
ASSOCIATED DISORDERS • Immune complexes form or are trapped in ○ Azotemia, hyperphosphatemia, hyperamy-
• Protein-losing nephropathy glomeruli. Although GN is often a primary lasemia, metabolic acidosis (in advanced
• Nephrotic syndrome process (idiopathic), many diseases can disease)

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