GI Dz's

• Fecal tests


  • Direct smear
  • Fecal float
  • Fecal float with centrifugation
  • Fecal sedimentation
• Lab work is not always performed for simple diarrhea or gastritis cases, but useful for sick patients to look for underlying diseases
• Abdominal Radiographs


  Used to diagnose GI foreign bodies, GDV, masses, perforations and constipation
• Abdominal Ultrasound


  Very useful for imaging the abdominal organs. Can be used to diagnose cancer, IBD, intussusception, pancreatitis, hepatic lipidosis, lymphangiectasia
• Ultrasound-guided biopsy


  Can be performed for lesions
• Exploratory laparotomy


  Surgical explore of the abdomen, useful for diagnosing and treating obstructions, taking full-thickness biopsies of the GI tract or ancillary organs, and visualizing all the organs
• Endoscopy


  Minimally invasive procedure performed under general anesthesia, used to visualize the mucosal lining of the GI tract, collect partial-thickness biopsies, and remove small foreign objects
• Disease specific tests


  • Spec cPL (canine pancreas-specific lipase)
  • Spec fPL (feline pancreas-specific lipase)
  • Trypsin-Like immunoreactivity (TLI)
  • Folate and Cobalamin/Vitamin B12
  • Giardia antigen test
  • Feline or Canine diarrhea PCR panels
  • Bile acids
• MRI (magnetic resonance imaging)


  Gives highly detailed images of the soft tissue organs and vasculature, performed at specialty hospitals or imaging centers
• Esophagitis


  Inflammation of the esophagus, can happen for a variety of reasons including swallowing an irritating substance, vomiting, or damage to the lower esophagus leading to reflux
• Gastroesophageal Reflux (GERD)


  Dysfunction of the lower esophageal sphincter leading to reflux of gastric components and further damage to the esophagus
• Some medications (like doxycycline) will damage the esophagus if they dissolve in the esophagus instead of the stomach
• Megaesophagus


  Dilated and flaccid esophagus, where food cannot be propelled into the stomach as the walls no longer contract normally, resulting in food sitting in the esophagus or being regurgitated
• Acute Gastritis


  Inflammation or irritation of the stomach lining, often caused by ingesting irritating substances
• Gastric Ulceration

  Most commonly caused by administration of non-steroidal anti-inflammatory medications (NSAIDs), can also be caused by stress, renal disease, liver disease, toxins, mast cell tumors and Addison's Diseases
• Gastric Dilation with Volvulus


  Life-threatening condition where the stomach fills with gas +/- ingesta and twists, severely reducing venous return to the heart and cutting off circulation to the stomach/spleen
• Gastric Neoplasia


  Gastric adenocarcinoma is the most common malignant neoplasia in dogs, and gastric lymphoma is the most common feline gastric tumor
• Gastric/Intestinal Obstruction


  Caused by animals eating inappropriate objects, can be partial or complete, and often requires surgery to remove the foreign object
• Hemorrhagic gastroenteritis


  Life-threatening condition in canines leading to hypovolemic shock, with severely inflamed intestines and bloody diarrhea and vomit
• Common fecal parasites


  • Coccidia
  • Roundworms
  • Whipworms
  • Hookworms
  • Giardia
• Viral diarrhea


  Caused by viruses like parvovirus, distemper virus, adenovirus, coronavirus, and panleukemia virus, can be fatal especially in puppies and kittens
• Bacterial diarrhea


  Caused by bacteria like Clostridium, Salmonella, Shigella, Listeria, Escherichia, Staphylococcus, and Campylobacter
• Dietary Intolerance Diarrhea


  Food allergies causing intestinal disease, treated with a novel protein or hydrolyzed protein diet
• Lymphangiectasia


  Lymphatic backup or malfunction leading to accumulation of lymph fluid in the intestinal walls, resulting in weight loss, chronic vomiting and diarrhea
• Bacterial infections that invade and damage intestinal epithelium

  • Shigella
  • Listeria
  • Escherichia
  • Staphylococcus
  • Campylobacter
• Bacterial infections


  • Release enterotoxins or invade the mucosal lining
  • Cause clinical signs including diarrhea, hematochezia, anorexia, fever
  • Diagnosed through fecal smear or PCR test
  • Treated with antibiotics and supportive care
• Many of these bacteria can affect humans as well as pets, so care is needed to wash hands carefully after cleaning the pet and yard
• Food allergies


  Common cause of intestinal disease in small animals
• Diagnosing food allergies


  1. Careful diet history

  2. Rule out other causes of vomiting, diarrhea, weight loss

  3. 6-8 week feeding trial with novel protein or hydrolyzed protein diet

  4. Treats, chews and other foods strictly restricted
• Lymphangiectasia


  Lymphatic backup or malfunction in drainage leading to lymph fluid accumulation in intestines
• Lymphangiectasia

  • Causes weight loss, chronic vomiting, diarrhea, ascites
  • More common in certain breeds like Yorkies, Wheaton Terriers, Maltese Terriers, Basenjis
  • Diagnosed through bloodwork, ultrasound, intestinal biopsies
  • Treated with steroids, immunomodulatory drugs, high protein/low fat diet
• Types of intestinal neoplasia

  • Lymphoma
  • Mast cell tumors
  • Adenocarcinomas
  • Leiomyoma/leiomyosarcomas
  • Polyps
• Inflammatory bowel disease (IBD)


  Syndrome of inflammation in the intestinal tract, cause not fully understood
• IBD


  • Can be focal or widespread, with different types of inflammatory cells
  • Causes chronic vomiting, diarrhea, weight loss, decreased appetite
  • Diagnosed through intestinal biopsies, other tests like fecal, bloodwork, ultrasound
  • No cure, but inflammation managed with diet and medications like steroids, anti-diarrheals, antiemetics, probiotics, deworming, B12 supplementation
• Intussusception


  When one part of the intestine telescopes into an adjacent part
• Intussusception


  • Caused by inflammation from parasites, infection, neoplasia, foreign body ingestion, or previous intestinal surgery
  • Occurs more commonly in younger animals and at the ileocecal junction
  • Causes partial to complete intestinal obstruction, requires surgery to resolve
• Megacolon


  Condition where the colon is unable to properly function, leading to constipation
• Megacolon


  • Causes include pelvic canal narrowing, spinal trauma, chronic conditions compromising colon function
  • Results in very hard, painful stools that accumulate in the colon over time
• Constipation


  Presence of desiccated feces in the colon
• Constipation


  • Not common without megacolon, can occur with chronic medications or poor diet