Lipase

What is lipase and what role does it play in digestion?

Lipase is one of several enzymes that are responsible for the digestion of fats. Fats consist of long chains of fatty acids that are bound to glycerol. Lipase breaks down these bonds and releases free fatty acids and glycerol. These can then be absorbed by the intestine and used by the body as a source of energy or as building materials for cells and hormones.

Lipase is mainly produced in the pancreas, a small organ located behind the stomach. The pancreas has two important functions: It produces digestive enzymes such as lipase, amylase and trypsin, which are passed into the intestine, and it produces hormones such as insulin and glucagon, which regulate blood sugar levels.

In addition to the pancreas, lipase is also produced in smaller quantities in the liver, intestine and fatty tissue. Lipase activity in the blood is measured by a special test called the TLI test (trypsin-like immunoreactivity). The normal TLI value in dogs is between 5 and 45 μg/l. A value above 45 μg/l is considered elevated and may indicate a disorder of fat metabolism or damage to the pancreas.

What symptoms can occur with an elevated lipase?

Elevated lipase can cause various symptoms, depending on the underlying cause. The most common symptoms are

• Diarrhea
• vomiting
• weight loss
• Loss of appetite
• abdominal pain
• fever
• jaundice
• dehydration

However, these symptoms are not specific to elevated lipase, but can also occur with other conditions. It is therefore important to have your dog examined by a vet if you notice such signs.

What are possible causes of elevated lipase?

There are several factors that can lead to elevated lipase. The most common are:

• Inflammation of the pancreas (pancreatitis). This is a serious condition caused by an overproduction or premature activation of digestive enzymes in the pancreas. The enzymes then attack the body's own tissue and cause swelling, pain and tissue damage. The causes of pancreatitis can be many and varied, such as a poor diet, medication, infections, injuries or genetic predispositions.
• Blockage of the bile duct (cholestasis). The bile duct is a channel that transports bile from the liver to the intestine. Bile is a fluid that helps with the digestion of fat. If the bile duct is blocked, for example by a stone or tumor, bile builds up in the liver and can lead to inflammation or infection. This in turn can increase lipase levels, as the liver also produces lipase.
• A liver disease (hepatopathy). The liver is an important organ that has many metabolic functions. It detoxifies the blood, stores sugar, forms proteins and hormones and produces bile. If the liver is damaged, for example due to poisoning, an infection, a tumor or a fatty liver, it can no longer perform its tasks and there is an increase in various enzymes in the blood, including lipase.
• Kidney disease (nephropathy). The kidneys are responsible for excreting waste products and excess water from the blood. If kidney function is impaired, for example due to inflammation, an infection, a stone or a tumor, waste products can no longer be excreted sufficiently and accumulate in the blood. This can lead to an increase in various enzymes in the blood, including lipase.

How is elevated lipase diagnosed and treated?

To diagnose elevated lipase, your vet will need to take a blood sample from your dog and have it analyzed in the laboratory. The TLI test measures the lipase activity in the blood and gives an indication of a possible disease of the pancreas or other organs. However, the TLI test is not always conclusive, as it can also be influenced by other factors such as stress or medication. For this reason, the TLI test should always be carried out in combination with other examinations such as an ultrasound scan or an X-ray of the abdomen in order to find the exact cause of the elevated lipase.

The treatment of an elevated lipase depends on the underlying cause. As a rule, treatment consists of the following measures:

• A bland diet for the dog. This should be low in fat, easily digestible and balanced. The food ration should be divided into several small portions so as not to overload the gastrointestinal tract. Your vet can recommend a suitable diet food or give you tips on how to prepare a light diet for your dog yourself.
• Adequate fluid intake for the dog. Since elevated lipase is often accompanied by diarrhea and vomiting, your dog can quickly become dehydrated. It is therefore important that he always has fresh water available and, if necessary, also receives an infusion to balance his fluid and electrolyte levels.
• Drug treatment for the dog. Depending on the cause and severity of the condition, your vet may prescribe various medications to alleviate the symptoms or inhibit the inflammation. These may include painkillers, antibiotics, anticonvulsants or hormones, for example.
• Surgical treatment for the dog. In some cases, surgery may be necessary to remove the cause of the elevated lipase. This may be the case, for example, if a gallstone or tumor is blocking the bile duct or if part of the pancreas needs to be removed.