Chronic iron overload causing haemochromatosis and hepatopathy in 21 horses and one donkey.

The research paper details a study that investigates cases of chronic iron overload in 21 unrelated horses and one donkey, leading to haemochromatosis and liver disease. Source of the iron overload was found to be high iron content in drinking water.

Objective and Methodology

• The objective of the case series was to investigate instances of chronic iron overload causing haemochromatosis and hepatopathy in 21 unrelated horses and one donkey.
• The research used animals that were presenting with clinical signs of chronic liver disease and were then diagnosed with iron overload and haemochromatosis.
• The diagnoses were made based on histopathological evaluations of liver tissue and/or evidence of transferrin saturation levels being above 80% in their blood, and the confirmation of excess dietary intake of iron.

Findings and Results

• This study included a total of 22 equids, 21 horses and one donkey.
• All tested animals had transferrin saturation levels above 80% and 21 out of 22 had increased level of gamma-glutamyltransferase, an enzyme that indicates liver disease.
• Ultrasonography performed on six horses revealed rounded liver margins in five of them and increased echogenicity in four.
• When examining the liver tissues of 12 animals histologically, they revealed inflammation of the liver, fibrosis (scarring), and haemosiderin (iron) accumulation in macrophages and hepatocytes (liver cells).
• In post-mortem examinations, all seven animals revealed haemosiderin accumulation in other organs as well.
• All the animals had been exposed to high iron content in drinking water for at least nine years before being diagnosed with haemochromatosis.
• Regarding the survival rate, 13 of the 22 animals were still alive by 1 January 2018, ranging from 17 to 79 months post their initial diagnosis.

Conclusions

• For 10 out of the 22 cases, liver tissue histology was not available for assessment.
• The research concluded that chronic iron overload can indeed lead to haemochromatosis and hepatopathy in equids.
• The development of these symptoms is slow and their clinical signs are nonspecific, making it a stealthy and dangerous condition.
• The conclusion also emphasises the importance of avoiding long-term excessive iron intake in equids (horses).
• For animals drinking from natural water sources, it is important to regularly test the water for its iron content to prevent such chronic conditions.