Elimination disorders are the most common behavioral problem seen in cats. Without the correct diagnosis, urination and/or defecation may continue for the life
of the cat and many cats, in this situation, are euthanized each year.
The first step in finding the cause of inappropriate elimination is to determine whether the act is behavioral or medical in origin. Common medical problems causing urination outside of the litter box include conditions causing irritation to the urinary tract such as urinary tract infections (UTI's), bladder stones, bladder tumors or bladder inflammation. Any metabolic condition that causes the cat to produce more urine can lead to urination outside the litter box. Common metabolic conditions include kidney failure, diabetes mellitus and hyperthyroidism. There are many less common conditions that can also lead to increased urine production.
Defecation (feces) outside of the litter box may also be due to a medical condition such as constipation or diarrhea. Sometimes problems with the urinary tract prompt passing stool outside the litter box and sometimes problems with the stool can lead to urinating outside the litter box. Arthritis can also prevent access to the litter box and prevent normal elimination habits.
Screening for medical problems is typically the first step in diagnosing inappropriate elimination disorders. A physical exam along with blood, urine and fecal (stool) tests, are done to determine if there is a medical cause to the house soiling. In some cases radiographs (x-rays) may be indicated.
If the physical exam and diagnostic tests are normal then we consider behavioral causes of inappropriate elimination. It is important to differentiate between urine marking, and inappropriate elimination. Marking rarely involves stool. When marking, typically the cat urinates small amounts from a standing or crouching position on vertical surfaces, such as furniture, walls or drapery. With inappropriate urination, cats tend to void their bladder completely in a crouched position on horizontal surfaces and may be seen scratching afterward.
The most important factor in solving behavioral inappropriate elimination is the litter box. As a general rule, there should be one more litter box than there are cats in the household, i.e. if there is one cat there should be two litter boxes. The cat should be comfortable with the location, size, type, and cleanliness of the litter box. Also the cat should be comfortable with the type of litter. Often a smorgasbord of litter boxes and litter types are needed to determine the cat's preferences. Manipulation of the home environment and sometimes medication are needed for a successful outcome.
Often there can be many factors that contribute to elimination outside of the litter box, and your veterinarian can help to identify contributing factors and create a plan to restore normal litter box behavior. Some studies have shown that up to 33% of cats eliminate inappropriately at some time in their lives. First eliminating medical causes, then addressing behavioral causes is an appropriate process for solving this problem and restoring a happy home environment for everyone.