Consensus Guidelines for Immunosuppressive Treatment of Dogs with Glomerular Disease Absent a Pathologic Diagnosis

Abstract

Background: In certain situations, veterinarians must decide whether or not to recommend immunosuppressive therapy for dogs with suspect glomerular disease in the absence of renal biopsy-derived evidence that active immune mechanisms are contributing to glomerular injury. The purpose of this report is to provide guidelines for the use of immunosuppressive drugs under these conditions. Animals: Animals were not used in this study. Methods: Recommendations were developed by a formal consensus method.Results: Four recommendations were developed and accepted at a high level of consensus (median 92.5% agreement). Renal biopsy should not be performed when contraindications are present or when results will not alter treatment or outcome. Immunosuppressive drugs should not be given when the source of proteinuria is unknown, they are otherwise contraindicated, or a familial nephropathy or amyloidosis is likely. However, they should be considered when dogs are already being given standard therapy and the serum creatinine is >3.0 mg/dL, azotemia is progressive, or hypoalbuminemia is severe. Thorough client communication regarding pros and cons of such treatment as well as close and careful patient monitoring is required.Conclusion and Clinical Importance: These recommendations can help guide the decision about renal biopsy in patients with proteinuria as well as the use of immunosuppressive drugs in those patients where the decision was made not to perform renal biopsy.

ACVIM consensus update on Lyme borreliosis in dogs and cats

“…No experimental model for Lyme nephritis is available, and it is difficult to study treatment protocols. Recommendations are based on antimicrobial treatment and standard diagnostic and treatment protocols for ICGN and PLN, as recommended by the IRIS Canine Glomerulonephritis Study Group . Proteinuria concurrent with seropositivity for an infectious agent with the potential to incite glomerular disease does not necessarily document a cause and effect relationship, even if clinical signs (eg, lameness) are seen.…”

“…Proteinuria concurrent with seropositivity for an infectious agent with the potential to incite glomerular disease does not necessarily document a cause and effect relationship, even if clinical signs (eg, lameness) are seen. Only < 30% of dogs with Lyme nephritis have a history of past or concurrent Lyme arthritis . Proteinuria is an uncommon finding, seen in <2% of Bb‐seropositive dogs .…”

“…For dogs with more severe, persistent, or progressive glomerular disease, or complications such as vomiting, dehydration, edema, effusions, or worsening azotemia, additional recommendations include antiemetics, crystalloids or colloids, aldosterone antagonist diuretics, phosphate binders, and treatments for chronic kidney disease as needed . In addition, immunosuppressive agents are indicated if there is biopsy‐confirmed evidence of an active immune‐mediated pathogenesis (eg, electron‐dense deposits by transmission electron microscopy, unequivocal immunofluorescent staining in the glomeruli), or even without biopsy confirmation in nonresponders or those with rapid progression, severe azotemia (serum creatinine concentration > 5 mg/dL) or severe hypoalbuminemia (serum albumin concentration < 2.0 g/dL) …”

“…For ICGN with profound proteinuria, hypoalbuminemia, nephrotic syndrome, or rapidly progressive azotemia, single drug or combination treatment consisting of rapidly acting immunosuppressive agents (Table ) is recommended in addition to antimicrobials and standard PLN treatments and diets . Immunosuppressive treatment is not without risk, especially in cases with concurrent diabetes mellitus, pancreatitis, active or latent bacterial or fungal infections, uncontrolled hypertension, hepatic dysfunction, or bone marrow suppression.…”

“…No experimental model to study its pathogenesis, treatment, and prevention in over‐represented (retriever) breeds has been developed, and no validated staining techniques are available to prove that glomerular immune‐complexes are Lyme‐specific in kidney biopsy specimens from living dogs. Despite these limitations, strategies for empirical management of Lyme nephritis are given, as recently offered by the International Renal Interest Society (IRIS) Glomerular Disease Study Group …”