Introduction
Foreign bodies of all types can be found in the intestines. While some may pass through posing no problems, others can cause acute obstruction. This is quite common in dogs, but rare in other species. Foreign bodies in other species such as ruminants tend to lodge in the oesophagus or in one of the ruminant stomachs. In horses, enteroliths can be seen in animals greater than 4 years of age and these can act as foreign bodies causing intestinal obstruction. Enteroliths are stones consisting of magnesium ammonium phosphate around a central nidus (often a metallic foreign body), they typically lodge at the pelvic flexure or the transverse colon. Smooth, round objects, such as golf balls, lodge especially near the pylorus or lower down. Occasionally in cattle (piece of rope or piece of tarpaulin) produces a tangled mass in rumen which causes pressure necrosis and eventually perforation. Foreign bodies can also be chronic, remaining for long periods of time without causing disturbance.
Clinical Signs
Obstruction at pylorus produces repeated vomiting. Obstruction lower down gives less dramatic effect. Vague signs of vomiting, weight loss and reluctance to eat may be present. In cats with linear foreign bodies wrapped around the tongue, then excess salivation, bleeding and reluctance to eat may also occur.
Diagnosis
Foreign bodies may not show up well radiographically (unless radio-opaque) for several days. The foreign bodies may also be objects that are semi solid or soft e.g. string, plastic bags or material (particularly in puppies). The intestines may appear knotted and 'puckered' in appearance. This is especially seen in cats which swallow string and the peristaltic movements cause it to pass through the intestine, yet it is attached to the tongue. This can cause the intestine to tear and may lead to severe peritonitis. This can also be seen in Horses which have ingested baler twine.
Treatment
Surgical removal may be neccesary if the foreign body cannot pass of its own accord. If the foreign body is in the large intestine then opening the intestines is not recommended due to bacteria infecting the abdominal cavity. If the object is able to pass through the small intestine then it should be able to pass through the large intestine.
If peritonitis has occured then abdominal lavage and intravenous and intra-abdominal antobiotics will be required as well as fluid therapy.
References
Blood, D.C. and Studdert, V. P. (1999) Saunders Comprehensive Veterinary Dictionary (2nd Edition) Elsevier Science
Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition) W.B. Saunders Company
Fossum, T. W. et. al. (2007) Small Animal Surgery (Third Edition) Mosby Elsevier
Merck & Co (2008) The Merck Veterinary Manual (Eighth Edition) Merial
Radostits, O.M, Arundel, J.H, and Gay, C.C. (2000) Veterinary Medicine: a textbook of the diseases of cattle, sheep, pigs, goats and horses Elsevier Health Sciences
Sturgess, K. (2003) Notes on Feline Internal Medicine Blackwell Publishing