Tag Archives: Lactulose

Portosystemic Shunts

1. What is a portosystemic shunt? A portosystemic shunt is an abnormal vessel that connects the portal vein to a systemic vein. The most common locations for portosystemic shunts are a patent ductus venosus or a connection between the portal vein and caudal vena cava or azygous vein. Single extraheptic shunts are most common in… Read More »

Perineal Hernia

Perineal hernias have been clinically recognized in the dog for more than 100 years and are most common in older, intact male dogs. They are rarely seen in cats or female dogs. Four types of perineal hernias have been described, but the most common type is the caudoventral perineal hernia, which occurs between the levator… Read More »

Rectal or Anal Stricture

Rectal or anal strictures cause narrowing of the lumen due to scar tissue that forms as a result of rectal inflammation, rectal trauma (from injury or surgery), or proliferative neoplastic disease in the rectum. The clinical picture (e. g., constipation, dyschezia, and, ultimately, vomiting or anorexia) is indistinguishable from that presented by extraluminal narrowing of… Read More »


Constipation; Cause The etiopathogenesis of idiopathic megacolon is still incompletely understood. Several reviews have emphasized the importance of considering an extensive list of differential diagnoses (e. g., neuromuscular, mechanical, inflammatory, metabolic and endocrine, pharmacologic, environmental, and behavioral causes) for the obstipated cat (Box Differential Diagnosis of Constipation in the Cat). A review of published cases… Read More »

Small Intestine: Special Tests

In cases of malabsorption, intestinal biopsy is usually necessary to obtain a definitive diagnosis. However, exocrine pancreatic insufficiency should be ruled out before biopsy, because signs of malabsorption are nonspecific. It is also well recognized that biopsies from up to 50% of patients are considered normal by light microscopy. Therefore, usually before biopsy, a number… Read More »

Inflammatory Bowel Disease

Inflammatory bowel disease is a collective term that describes a group of disorders characterized by persistent or recurrent gastrointestinal signs and histologic evidence of intestinal inflammation on biopsy material. The disease bears little resemblance to inflammatory bowel disease (Crohn’s disease and ulcerative colitis) of humans, and indiscriminate use of the term “IBD” is no more… Read More »