Description of the Use of Plasma Exchange in Dogs With Cutaneous and Renal Glomerular Vasculopathy

Abstract

Cutaneous and renal glomerular vasculopathy (CRGV) is a rare disease affecting dogs, with a recent apparent increase in prevalence since 2012 in the UK. This disease is characterized by a vasculopathy affecting small vessels of the kidney and skin, leading to thrombotic microangiopathy. The underlying etiology remains unknown although clinicopathological and histological findings resemble features of certain forms of thrombotic microangiopathy in people, for which plasma exchange (PEX) is considered an important component of therapy. The objective of the present study is to describe the use of PEX as adjunctive treatment in dogs diagnosed with CRGV. A retrospective review of dogs diagnosed with CRGV between 2014 and 2016 treated with PEX was performed. Clinical records were reviewed and data relating to signalment, diagnostic tests and management strategies were summarized. Information and complications relating to PEX were recorded. Six dogs were diagnosed with CRGV (n = 2 ante-mortem, n = 4 post-mortem) and underwent PEX as part of their therapy. All dogs had cutaneous lesions and were azotemic with oliguria or anuria. All dogs underwent at least one PEX cycle; one dog had a single cycle PEX, three dogs two cycles PEX, and two dogs had one cycle PEX and one cycle of prolonged intermittent renal replacement treatment. Complications seen during PEX therapy included hypothermia (n = 4), tachycardia (n = 2), hypotension (n = 2), and hypocalcemia (n = 6). Two dogs survived to discharge, the remaining four dogs were euthanized. The positive outcome in two dogs treated with PEX despite the reported high mortality rate once acute kidney injury with oliguria/anuria occurs does not confirm success of this treatment. However, survival in two dogs that were initially oligoanuric highlights that further consideration and evaluation of PEX for this patient group is warranted for this specific disease. Additional studies are urgently needed to identify the underlying etiology of CRGV before more targeted therapies can be developed. Based on our findings, further evaluation of the role of PEX in this specific disease are warranted.

Hypertension, retinopathy, and acute kidney injury in dogs: A prospective study

“…Oliguria was defined as a urine output less than 1 mL/kg/hr for >6 hours 2 . Fluid overload (FO) was diagnosed by the attending clinicians who determined this based on a daily dog assessment including monitoring for acute weight gain, serous nasal discharge, chemosis, subcutaneous edema or detection of cavitatory fluid with ultrasonography 14 . Proteinuria was defined as UPCR >0.5 with an inactive sediment 15 .…”

Membrane‐based therapeutic plasma exchange in dogs: Prescription, anticoagulation, and metabolic response

“…Although most treatments are initially inspired by human protocols, extrapolation to dogs and cats with their diseases and their specific pathophysiological, cardiovascular, and metabolic responses has limitations. Small animal protocols therefore need to be established based on species‐specific data, but few cases have been published, reporting its use in toxicoses, hyperviscosity syndromes, immune‐mediated diseases, and microangiopathy …”

Extracorporeal therapies in veterinary medicine: what is currently performed in the UK?

“…A phenotypically similar set of diseases (thrombotic microangiopathies) are often treated with TPE in people, and thus we offer TPE in select cases of CRGV (Case study 2). There has been a published description of the use of TPE in these patients (Skulberg and others 2018), but research into the underpinning pathophysiology, and thus ideal clinical management, is ongoing. Although the use of TPE for CRGV holds potential, it cannot be considered a cure at this stage.…”