Lundehund Intestinal Syndrome
Lundehund Intestinal Syndrome is a combination of stomach and intestinal diseases: (Intestinal Lymphangiectasia, Lymphocytic-Plasmacytic Inflammatory Bowel Disease and Gastritis, Protein Losing Enteropathy and Small Intestine Bacterial Overgrowth) leading to malabsorption and protein loss/deficiency.
It can eventually lead to lymphoma, or cancer of the intestines or stomach, sometimes with consequent perforation.
- low serum protein, especially albumin (sometimes that is the only sign)
- weight loss, especially loss of muscle mass
- loss of appetite
- lethargy, weakness
- swollen abdomen (looks pregnant) and/or swollen legs
- Onset: any age, dogs from 6 months to 10 years have gotten it.
At this point, the cause is totally unknown. Certainly there is a genetic predisposition to the disease, and then something sets it off. Intestinal infections (viral, parasitic, and bacterial) have been implicated. Periods of stress (boarding, estrus, pregnancy, dog shows) seem to bring on episodes. The Lymphangiectasia component can be either a congenital blockage of lymph vessels or an adult blockage of the lymphatics by inflammatory cells. The IBD component is likely a hypersensitivity/allergy to protein antigens (either from food or bacteria) that are in or pass through their GI tract. In IBD the normal protective mechanisms of the intestines are reduced, allowing increasing leakage in the intestinal wall so that the intestines are exposed to substances they would not normally see.
Course of the disease
Lundehunds may either be born with intestines that already have lymph blockage or they may have normal intestines in which inflammatory cells build up in the linings. Regardless of the cause, the lymphatic vessels (which normally absorb proteins from food) clog up and ooze protein/lymph back into the intestines. Some dogs get the clogged up lymph vessels (lymphangiectasia) worse than others and lose protein quickly with no signs of diarrhea. Other dogs get the inflammatory build-up worse and are more prone to diarrhea first. Either way, the dog is not able to absorb nutrients and protein from its food, plus it is also losing protein from its body into the gut.
Many dogs get an intestinal bacterial overgrowth and those bad bacteria use up vitamin B12 (Cobalamin) in the intestine. A B12 deficiency causes even more damage to the intestines, produces malabsorption and worse diarrhea. This malabsorption can cause even more weight loss. The loss of protein occurs insidiously, sometimes with no symptoms, until the weight loss is so obvious it can’t be ignored. Weight loss (especially loss of muscle mass) will progress to a severe level as the process continues.
Some dogs will improve on their own, or with treatment, and the disease will appear to go away. But actually it is only in remission. Later on, especially after periods of stress and change in the dog's life, it will usually reappear. Repeated bouts can occur, but can usually be controlled with medication. Eventually, the disease process can become so advanced that the walls are permanently clogged with cells or the intestinal villi (absorption areas in the gut) become permanently damaged. Then the body can no longer digest enough food and the dog progressively loses weight. Once they have lost enough protein, the abdomen swells up with fluid accumulation (recall photos of malnourished children with big stomachs?) and/or the fluid will accumulate in the limbs, usually the hind legs. Sometimes the fluid may also build up inside the chest, causing breathing problems.
Death can occur due to dehydration, extreme anemia & malnutrition, abdominal/chest fluid build-up, or they will throw a blood clot to the brain or other vital organ. Like IBD in cats, the cell build-up can lead to lymphoma, or intestinal cancer or stomach carcinoma. In three cases that I know of, this has caused a perforation of the intestine or stomach, leading to acute death.
Current treatment uses special food, (high protein, low fat and/or hypoallergenic foods), and drugs to reduce the cell build-up in the intestines, improve the lymphatic flow and eliminate the bad intestinal bacteria. The most common treatments are prednisone, metronidazole, cimetidine, FOS, Forti-flora, B12 injections. Treatment varies with each individual dog.
I have an article with extensive information that I can share with your veterinarian if that person is willing to contact me.
Most Lundies will get numerous attacks througth their life. Bouts of the disease can be controlled with medication. In the first half of their life, when a Lundie has an attack the prognosis is fair to good. The illness can go into remission for various periods of time, and the dog can live for many years. As the dog gets older, more damage occurs in the intestines and the prognosis decreases with age. However it is dangerous to make generalizations when dealing with the outlook of a disease; any dog can get a fatal attack anytime in its life.
However, we are learning more and more about the illness as time goes on; this makes treatment more effective. Medical researchers, as well as practitioners treating Lundehunds, learn something new about it every year.
Incidence in the Lundehund Breed
At present is unknown. It is difficult to gather firm figures. The disease can appear at any age and some dogs get such a mild case that no one really ever diagnoses it. Certainly Lundehunds get this disease incredibly more often than other breeds, and most will have an attack sometime in their life. Researchers have 'guestimated' the incidence as low as 40% and as high as 100%.
Intermittent research is being done on treatment and diagnosis in the United States. However, progress is slow as this disease has multiple and variable manifestations, so is not simple to pin down. And the Lundehund's small population of owners make it a poor economic gamble for commercial research. Each year, bit by bit, more information is gathered by academic research on this disease process, in other breeds as well as Lundehunds.
Have serum protein levels done very often, at least twice a year on a healthy dog and once every 2-3 months on a dog who has had an attack or is older than six. Have fecal tests done every 6-12 months, for fecal alpha protein, parasites and giardia. Protein levels in the blood can drop low weeks or months before the dog starts acting ill, so catch it early.
Contact the GI Lab at Texas A & M to participate in any on-going research they may be doing for Lundehunds. There will usually be one or two projects on-going at any one time, when they can get funding. Donations to the GI Lab are always welcome for the research, whether you need a tax write-off or not. (See link on Contacts page.)
REMEMBER: regular check-ups and catching an attack early prolong the life of your Lundehund and are less costly than going to ER. A perfectly healthy acting dog on the outside can have intestines getting sick on the inside---so practice preventive medicine.
Susan Torgerson, D.V.M.