The bright and friendly Mini Schnauzer is, without a doubt, our number one client. Unfortunately, these lovely dogs are prone to a number of diseases, for which nutrition is a key part of management. Diabetes mellitus and calcium oxalate urolithiasis (stones) are two good examples. Mini Schnauzers can also be at increased risk for pancreatitis, and sometimes this is due to hyperlipidaemia, which is an increased concentration of lipids (triglycerides, cholesterol or both) in the blood.
Hyperlipidaemia can be either primary, or secondary to other diseases. In dogs, secondary hyperlipidaemia is the most common form, and it can be a result of endocrine disorders (such as hypothyroidism or diabetes), very high fat diets, cholestasis, severe obesity, or the use of particular drugs (phenobarbital, glucocorticoids etc). Primary hyperlipidaemia is much less common, however, it can occur frequently within certain breeds. Hypertriglyceridaemia of Mini Schnauzers is the most common form of primary hyperlipidaemia, but other breeds can also be affected. In 2015, Xenoulis and Steiner published a review paper titled 'Canine hyperlipidaemia'; which provides a good overview of this condition, including its causes, diagnosis, and treatment.
Less frequently discussed is the association between hyperlipidaemia and proteinuria in Mini Schnauzers. In 2016, Furrow et al. published this paper: 'Proteinuria and lipoprotein lipase activity in Miniature Schnauzer dogs with and without hypertriglyceridemia'. The authors note in their introduction that hyperlipidaemia, including both hypertriglyceridaemia and hypercholesterolaemia, can cause kidney injury in humans and rats, a concept termed ‘lipid nephrotoxicity’. Hence, the aim of their study was to determine the relationship between hypertriglyceridaemia and proteinuria in Mini Schnauzers.
What the authors found was that proteinuria was present in 60% of dogs with hypertriglyceridaemia, and absent from all dogs without hypertriglyceridaemia. Proteinuric dogs were not azotaemic or hypoalbuminaemic. They concluded that proteinuria frequently occurs with hypertriglyceridaemia in Mini Schnauzers, and speculated that it could be due to lipid-induced glomerular injury. They did comment that, at that stage, it was difficult to determine which abnormality was primary – the hyperlipidaemia, or the proteinuria.
In 2017, Furrow et al. published a second paper, further investigating the potential cause of proteinuria in hyperlipidaemic Mini Schnauzers. They examined renal tissue from 27
proteinuric Miniature Schnauzers, which revealed that 20 dogs had ultrastructural evidence of osmophilic globules consistent with lipid in glomerular tufts. Seven of these dogs had lipid thromboemboli in glomerular capillary loops that distorted their shape and compressed circulating erythrocytes.
This research highlights the need to be vigilant with respect to the diagnosis of hyperlipidaemia in Mini Schnauzers, so that appropriate management can be instituted prior to the development of proteinuria and renal damage. Regular monitoring of fasted (12 hours) serum triglycerides is advisable, and if elevated, appropriate therapy (including a very low fat diet) can be promptly commenced.
If you have a Mini Schnauzer and you are concerned about your dog's diet, email us: info@vngpets.com
Read the Xenoulis and Steiner review here: https://www.ncbi.nlm.nih.gov/pubmed/26456868
Read the Furrow et al. (2016) paper here: https://www.ncbi.nlm.nih.gov/pubmed/27256031
Read the Furrow et al. (2017) paper here: https://www.ncbi.nlm.nih.gov/pubmed/28005494
Disclaimer: This content is not intended to be a substitute for the professional recommendations of your pet's veterinarian. Always seek the advice of your veterinarian with any questions you may have regarding the medical condition of your pet. If you think your pet has a medical emergency, please call or visit your veterinarian or your local veterinary emergency hospital immediately.