Characteristics and outcome of 73 dogs with iron EDTA molluscicide ingestion in Melbourne, Australia (2013-2019).

Introduction: The objective of this study was to describe the clinical features, treatments and outcomes of dogs with iron ethylenediaminetetraacetate (EDTA) molluscicide ingestion. We aimed to identify potential predictors of serum iron concentration >54 μmol/L; a cut-off recommended for initiating treatment of human iron toxicosis.

Methods: Medical records across four veterinary hospitals (2013-2019) for dogs with known or suspected iron EDTA molluscicide ingestion were reviewed for signalment, clinical signs, clinicopathological data, treatment regimens and outcomes. Clinical signs of dogs with serum iron concentrations either below or above a cut-off of 54 μmol/L were compared using Fisher's exact test. Association between serum iron and urine discolouration was tested using logistic regression.

Results: Seventy-three dogs were included. The most frequent characteristic was abnormal faeces (n = 47, 64%) as determined by rectal examination, with more dogs that had serum iron >54 μmol/L showing this clinical sign (24/35), compared to dogs with serum iron <54 μmol/L (4/13) (P = 0.025). Clinicopathologic abnormalities included increased base excess (n = 20/49, 20%), hyperglycaemia (n = 13/57, 23%) and hyperlactataemia (n = 12/57, 21%). Fifty-four dogs received deferoxamine chelation (74%), during which 25/42 (60%) dogs had discoloured urine despite all dogs having subsequent iron concentrations <54 μmol/L. Admission serum iron concentration was associated with urine discolouration during hospitalisation (odds ratio 1.046, 95% confidence interval 1.008-1.107, P = 0.011). Sixty-nine dogs (95%) survived to discharge, with 10 dogs (14%) transferred to another veterinarian.

Conclusions: Iron EDTA molluscicide ingestion caused predominantly gastrointestinal clinical signs, and abnormal faeces, as well as urine discolouration during chelation therapy, which may indicate an elevation of serum iron concentration on presentation. Outcome was excellent.