Pet Talk: Linear Foreign Bodies in Dogs and Cats | Characteristics

Pets have the annoying tendency to eat things they shouldn’t eat, and we’re not talking about food. Toys, socks, stones and other materials end up in the stomachs of animals. But when the foreign body is a string, the consequences are particularly serious. Animals like to play with things, and the game often involves chewing. Chewing leads to accidental swallowing, and from there disaster can ensue. Animals of all ages will play with toys, but it is usually younger people who have problems with foreign objects. Common items that are swallowed include corn on the cob, balls, socks and underwear, stones, jewelry, toys, leashes and collars, plastic bags, pieces of shoes, coins. coins, sewing needles and hooks. Often times, these objects will pass out on the other end within a day or two, although it is possible for a small object to shake the stomach without passing for weeks. If the object does not pass and causes an obstruction or partial obstruction, surgery will be necessary to remove it. Prompt diagnosis allows rapid elimination of the foreign body before the intestine is seriously damaged. In more advanced situations, damaged sections of the intestine must be removed and in the worst case, the intestines open up and spread bacteria and digested food throughout the abdomen. The latter possibility is associated with a very high mortality rate and should be avoided at all costs. As if that were not enough, there is an especially serious foreign body situation when the object is a chain or similar linear structure. Common linear foreign objects can include string, thread, or garlands during this Christmas season.

Imagine a drawstring bag. Tie a knot in one end of the cord so that it cannot move and pull on the other end. The fabric goes up along the channel of the twine. If the twine has been pulled hard enough and the knot still does not move, the twine will actually tear through the twine channel. This is what happens in the linear foreign body scenario. The foreign body is lodged somewhere in the gastrointestinal tract and will not move. The string, however, hangs forward in the gastrointestinal tract like a drawstring. The intestine tries to move it forward, but as the foreign body is lodged, the intestine eventually pushes the string up like the cord channel on the pants or like an accordion. This type of folding in on itself is called plication and is the hallmark of the linear foreign body. If the linear foreign body is not removed, it can lead to life-threatening peritonitis.

Linear foreign body is particularly difficult to diagnose. The threads are too small to be seen on x-rays. Often the only clue is evidence of plication on the x-ray or ultrasound, and even then the pattern is unlikely to be definitive. The decision to go for surgery will likely have to be made based on the patient’s condition and the information from the imaging.

Linear foreign body surgery is generally considered to be a higher mortality situation than simpler foreign body surgery. The major concern of all vets is that the linear foreign body has not damaged the intestines or cut them to allow secondary peritonitis. Don’t let your dogs and cats play with yarn, string, ribbons or garlands this Christmas time.

Dr Karsten Fostvedt is a veterinarian at the St. Francis Pet Clinic in Ketchum.