Diabetic ketoacidosis (DKA) is a critical state in which the blood becomes too acidic for normal physiological cell functions to operate due to abnormal metabolism. This most commonly occurs due to prolonged unregulated diabetes mellitus. Let’s start with discussing diabetes, and working our way up to DKA.
Understanding Diabetes in Dogs
Diabetes mellitus is the abnormally high accumulation of sugar (glucose) in the bloodstream due to the body’s inability to bring it into the cells. This is most often insulin dependent in dogs, similar to Type I Diabetes in people.
Insulin is a hormone that officiates the transportation of sugar molecules from the circulating blood into the cells. Normally the pancreas produces insulin, but in diabetics, the production is minimal to absent. The cause is often unknown, but may be secondary to genetic disturbances, pancreatic cell damage (from viral infections or possibly recurrent and chronic pancreatitis), or chronic steroid exposure.
Excessive steroid exposure can either be due to iatrogenic causes, meaning the animal is receiving too many steroids from an outside source (pills, injections, or topicals [exogenous]), or secondary to another endocrine disease called Cushing’s Disease or Hyperadrenocorticism, where the adrenal glands produce too many endogenous steroids. Also obesity is a predisposing factor.
The problem is, even though there is plenty of sugar in the blood, if there is not enough insulin to transport it into the cells, the cells think they are starving. When this happens, the cells start turning on their backup systems to get energy to maintain normal cell functions. That means they start breaking down fat and proteins, which are less efficient than carbohydrates. One of the byproducts of protein breakdown is ketones.
Diabetes with Ketones in Dogs
Ketones by themselves are not harmful. The issue is that, when they build up in the bloodstream, it makes the blood acidic. Cell functions only operate within a specific pH range, so when the blood becomes too acidic, the normal pathways start shutting down, leading to a sick patient. This is what is known as Diabetic Ketoacidosis.
Dogs can sometimes compensate for a while with diabetes. It’s usually a second or concurrent illness that pushes them over the edge and leads to DKA.
Clinical signs that are consistent with diabetes include drinking and urinating a lot, weight loss, and possibly recurrent urinary tract infections. If the blood sugar gets high enough, the central nervous system can be affected and seizures are possible. Clinical signs of a DKA patient are those of uncomplicated diabetes and may also include dehydration, lethargy, decreased appetite, vomiting and diarrhea, heavy breathing, and even shock.
Diagnosing diabetes is fairly easy. The definitive diagnosis is made with a blood sugar level over 300 ug/dL in conjunction with the presence of sugar in the urine. A full blood work panel should be run for completeness to avoid missing any secondary and complicating factors. Detecting DKA is a little more complicated since the acid-base level needs to be measured via a test called blood gasses. Also the presence of ketones in the urine is often found, but absence does not rule out DKA.
Dog Diabetic Ketoacidosis Treatment
Diabetes is not a curable disease, but it can be managed. Very rarely in dogs does it go into remission. Mainstays of diabetic management include insulin therapy (most often requires owners to give injections at home twice a day), special diets, consistent schedule and diet, and weight loss.
It is very important to be cautious with insulin as too much could cause the blood sugar to be too low (hypoglycemia), which can be detrimental.
It is good practice to have the pet observed at the clinic when starting insulin, and have their blood sugar checked throughout the day to make sure it does not go too low. The pet will then be sent home after the owners are taught how to give the insulin injections, and rechecked in a week or two.
Additionally, it is important to treat any underlying cause, avoid medications that can lead to insulin resistance (steroids, cyclosporine, and progestins) when possible, and spay intact females, as spikes in hormones may affect blood sugar levels (Behrend, et al. 2018)
DKA patients are typically more critical and require hospitalization for at least a couple days. This involves IV fluids for stabilization, correction of electrolyte and acid-base imbalances, and treatment of any secondary or underlying diseases. Once rehydrated, insulin therapy can be initiated to return the blood sugar back to normal. Care must be taken not to drop it too quickly, because a sudden and drastic drop in blood sugar can cause the brain to swell.
Consistency is key when managing a diabetic. This includes diet type, amount (including treats) and timing. Any change can offset the balance and potentially put the dog back in crisis. Most of the time, insulin therapy will be for life. It is imperative that the dose given is the one that was recommended by the veterinarian. Any alterations in dosing needs to be carefully monitored and should only be done at the direction of the veterinarian.
At home monitoring can be accomplished with urine dipsticks or blood sugar sticks with a veterinary approved glucometer. Luckily, dogs do not need to be as strictly regulated as humans do. The goals of therapy are to control the clinical signs and avoid hypoglycemia.
It is important to know what to expect as managing this disease can be frustrating, time consuming, and expensive. However when properly regulated, the pet can enjoy a good quality of life.
Behrend, Ellen VMD, PhD, DACVIM, Holford, Amy VMD, DACVIM, Lathan, Patty VMD, DACVIM, Rucinsky, Renee DVM, DABVP, and Schulman, Rhonda DVM, DACVIM. 2018 AAHA Diabetes Management Guidelines for Dogs and Cats. https://www.aaha.org/ guidelines/diabetes_guidelines/default.aspx
About the Author
Dr. Eric Weiner is a small animal veterinarian practicing in Orlando, Florida. He is a third generation veterinarian as both his father and grandfather are vets. Although he grew up following both of them around and wanted to be a veterinarian himself, he took a bit of a detour and attended Hofstra University originally as a music major.
Eventually realizing his true passion still lays within Veterinary Medicine, he switch majors and graduated in 2010 with a BA in biology and dual minors in biochemistry and music. Dr. Weiner attended Virginia-Maryland Regional College of Veterinary Medicine and graduated in 2015, concentrating in mixed animal medicine and surgery.
During his clinical year, his favorite rotation was which ever he was currently on. He especially enjoyed spending time at the Penn Vet Working Dog Center, where he worked closely with search and rescue dogs, diabetic alert dogs, and even cancer detection dogs.
When Dr. Weiner is not working with animals, he enjoys riding his motorcycle and playing baseball. He is married to his high school sweetheart and they are enjoying their brand new baby girl. In addition, they live with their therapy dog Murphy, and two cats, Stella and Luna.