Predicting Outcome in dogs with Primary Immune‐Mediated Hemolytic Anemia: Results of a Multicenter Case Registry

Abstract

BackgroundOutcome prediction in dogs with immune‐mediated hemolytic anemia (IMHA) is challenging and few prognostic indicators have been consistently identified.ObjectivesAn online case registry was initiated to: prospectively survey canine IMHA presentation and management in the British Isles; evaluate 2 previously reported illness severity scores, Canine Hemolytic Anemia Score (CHAOS) and Tokyo and to identify independent prognostic markers.AnimalsData from 276 dogs with primary IMHA across 10 referral centers were collected between 2008 and 2012.MethodsOutcome prediction by previously reported illness‐severity scores was tested using univariate logistic regression. Independent predictors of death in hospital or by 30‐days after admission were identified using multivariable logistic regression.ResultsPurebreds represented 89.1% dogs (n = 246). Immunosuppressive medications were administered to 88.4% dogs (n = 244), 76.1% (n = 210) received antithrombotics and 74.3% (n = 205) received packed red blood cells. Seventy‐four per cent of dogs (n = 205) were discharged from hospital and 67.7% (n = 187) were alive 30‐days after admission. Two dogs were lost to follow‐up at 30‐days. In univariate analyses CHAOS was associated with death in hospital and death within 30‐days. Tokyo score was not associated with either outcome measure. A model containing SIRS‐classification, ASA classification, ALT, bilirubin, urea and creatinine predicting outcome at discharge was accurate in 82% of cases. ASA classification, bilirubin, urea and creatinine were independently associated with death in hospital or by 30‐days.Conclusions and clinical importanceMarkers of kidney function, bilirubin concentration and ASA classification are independently associated with outcome in dogs with IMHA. Validation of this score in an unrelated population is now warranted.

ACVIM consensus statement on the treatment of immune‐mediated hemolytic anemia in dogs

“…Administration of cyclosporine to dogs with IMHA is reported in numerous studies . In 1 retrospective cohort study, the use of cyclosporine (in combination with other drugs) did not change the relative risk of death compared to all other treatment protocols that excluded the drug, although this study was limited by incomplete description of the treatment regimens (Figure ) .…”

“…Among the latter models, increased serum bilirubin concentration (or clinical icterus) and increased serum urea or BUN concentration were identified as independent predictors of mortality in 2 studies of different patient populations . Both prognostic factors subsequently were identified by a further study of dogs with IMHA in the United Kingdom . We suggest therefore that evaluation of serum bilirubin and urea concentrations may be of greatest utility in predicting outcome for dogs with IMHA (published values shown in Table ), although several other factors have been identified as single predictors …”

Fractional excretion of electrolytes in volume‐responsive and intrinsic acute kidney injury in dogs: Diagnostic and prognostic implications

“…These data are preliminary and partially in line with the available literature on AKI in dogs . In addition, the prognostic role of hyperbilirubinemia, metabolic acidosis, and hypocalcemia has been suggested previously in critically ill dogs in different clinical settings, particularly during sepsis . For these reasons, in our cohort, their prognostic role might have been influenced by factors other than renal damage, as well as by AKI etiology (eg, leptospirosis, sepsis), and requires further assessment.…”

Neutrophil Extracellular Traps in Plasma from Dogs with Immune‐mediated Hemolytic Anemia

“…Immune‐mediated hemolytic anemia is a devastating disease associated with high mortality, and the marked inflammatory nature of IMHA may be an important contributor to mortality. Dogs with IMHA often have a marked leukemoid response, and may develop systemic inflammatory response syndrome along with its devastating sequelae .…”