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An Urban Experience
F. Gaschen1
1Louisiana State University, Baton Rouge, LA USA
Constipation is characterized by infrequent or difficult evacuation of feces. Obstipation is the result of recurrent, intractable constipation. Constipation and obstipation may culminate in the syndrome of megacolon. Constipation is a relatively frequent problem in cats while obstipation and megacolon are less common
Primary constipation is due to abnormal colonic
motility. Neuromuscular dysfunction may occur in animals with lumbosacral disease or in cats with idiopathic megacolon. Dehydration, hypokalemia, and hypocalcemia may all negatively impact colonic motility. Inactivity and obesity may also be a cause of prolonged large bowel transit time. Furthermore, use of opiates and anticholinergics may also lead to constipation.
Secondary constipation is more common and is associated with processes that impair the transit and evacuation of colonic content, such as mechanical obstruction of the colon or rectum. Obstructions can be intraluminal (e.g. fecal impaction, FB, stricture), intramural (neoplasia), or extramural (e.g. narrowing of the pelvic canal, space-occupying lesions impinging on the descending colon or rectum).
consisting of CBC, biochemistry panel, and urinalysis should be obtained in all cats presented for constipation to rule out metabolic causes and underlying chronic diseases such as chronic kidney disease. Abdominal radiographs help characterize the severity of colonic impaction and identify predisposing factors such as intraluminal radiopaque foreign material, intraluminal or extraluminal mass lesions, pelvic fractures, and spinal cord abnormalities. Extraluminal mass lesions may be further evaluated by abdominal ultrasonography and guided biopsy, whereas intraluminal mass lesions are best evaluated by endoscopy.
Diseases of the anorectum such as anal sacculitis
may cause painful defecation. Pseudocoprostasis or constipation can be caused by matted hair around
the anus, which occasionally occurs in long haired cats. Importantly, some cat owners may not be able to differentiate stranguria and dyschezia, and lower urinary tract diseases should always be ruled out.
All identified underlying problems should be treated. If the cause of the obstruction can be addressed in a timely manner, colonic function may be preserved. However, prolonged obstruction is ultimately associated with loss of colonic contractility.
The different methods for treatment of idiopathic, nonobstructive constipation include administration of oral laxatives, enemas (Table 1) and prokinetic agents such as cisapride (0.1-0.5 mg/kg PO q8-12h).
Table 1:
In cats with chronic recurrent idiopathic constipation, a stepwise approach has proven useful. Mild to moderate constipation (e.g. first occurrence, recurrence after a long interval with normal defecation) is best treated
with an initial enema followed by treatment with laxatives. Maintaining these cats on a psyllium-enriched diet or continuing daily administration of laxatives is recommended. Addition of prokinetics is necessary
Typical clinical signs include reduced, absent, or painful defecation, and may be progressive. Other clinical signs associated with a primary underlying disease might be present. The onset of distal bowel signs may be insidious and animals may be presented late when the problem is severe. Dyschezia may be observed. Chronic constipation/obstipation may have systemic repercussions such as anorexia, lethargy, weight loss, and vomiting.
A detailed physical examination is required. This may reveal varying degrees of dehydration, weight loss, and abdominal pain. Rectal palpation (performed under sedation) is challenging in cats, but might reveal pelvic canal abnormalities, a stricture, etc.
A thorough screening of animals presented with recurrent constipation is recommended to identify obstructions and underlying diseases and assess the systemic repercussions of the problem. A minimal database

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