Small animal acute gastroenteric dx

How does acute V and D cf to chronic?

• Most acute is self limiting

• Most chronic requires specific diagnosis before treatment

How can you categorise acute vomiting and diarrhoea? GIve examples of each category

• Non-fatal / self-limiting

  • Ex parasitism or dietary indiscretion

• 2° to extra-intestinal / systemic disease

  • Ex. pancreas, kidney, liver, endocrine (addison's)

• Severe potentially life-threatening

  • Enteric infection

    • Ex- Parvovirus, bacterial

  • AHDS (acute haemorrhagic d+ syndrome) /HGE (haemorrhagic gastroenteritis)

  • Intestinal obstruction

  • Surgical disease

    • Ex- intussusception, volvulus, foreign body etc

What is the most important part of supportive care/ treatment for diarrhoea?

Prevention of dehydration

Where is most water absorbed in the gut of a dog?

Jejunum>Ileum> Colon

How do vomiting and diarrhoea occur when they occur sequentially?

Can also freq occur together

(tenesmus = straining)

Where can we localise diarrrhoea to?

• Gastric (gastritis)

• Small intestine (enteritis)

• Large intesine (colitis)

What features help to localise diarrhoea to the small vs large intestine?

How does vomiting and diarrhoea present in acute gastritis?

• Acute onset of frequent vomiting

• Often associated with acute diarrhoea

• Very common

• Often self-limiting

What are the causes of acute gastritis?

• Many causes; not all ‘inflammatory’

  • Dietary indiscretions, garbage intoxication

  • Foreign material

  • Hairballs (bezoars) in cats

  • Certain drugs

  • Acute systemic disease

How does diarrhoea present in acute enteritis?

Acute onset of profuse diarrhoea

• Normal to increased frequency

• No tenesmus

• +/- digested blood (melaena)

• Large volume

• Often associated with acute vomiting

• Usually self-limiting

What are the causes of acute enteritis?

• Aetiology often obscure

• Usually self-limiting

• Dietary indiscretions, garbage intoxication

• Enteric infection

acute V+

How does acute colitis present?

• Acute, frequent, small volume D+

  • Excessive straining = tenesmus

  • Mucoid faeces

  • ± fresh blood = haematochezia

• Incidence

  • Fairly common in dog; rare in cat

What are the causes of acute colitis?

• Idiopathic

• Garbage ingestion

• Whipworms

• Protozoa (Giardia, Cryptosporidia etc)

How do you make a diagnosis with a diarrhoea and vomiting case?

• Hx

• Physical examination

• Minimum data base

• Imaging

• Response to symptomatic treatment

• Reassess if signs persist for > 48 hours

What history should you take for a V and D case?

• Age and vaccination status

• Recent dietary intake

• Exposure to toxins, f.b. or infectious disease

• Nature of signs

  • Onset and severity

  • Content of vomit

  • Stool characteristics

  • Presence of blood

What should you look for in a physical exam of a dog with V and D?

• General body condition

  • Hydration

    • PCV / TP

    • MM

    • Skin tenting

• Oral and rectal examination

• Abdominal palpation

When should you perform diagnostic tests in a V and D case

• Super bright comfortable abdomen- probably see if self resolves

• If in pain, more severe or reoccurence then need to do further tests

What are the minimum database tests to carry out for a V and D case?

• Haematology

• Serum biochemistry

• Urinalysis

• Faecal examinations for parasites

• Other faecal examinations ?

What faecal microbiology tests can be done for a V and D case?

• Bacterial culture indicated if

• Virology

  • ELISA test for viral antigen

  • Electron microscopy

• • Parasitology

  • Direct smears and flotation (e.g. Giardia)

  • Wet-prep for Tritrichomonas (cats)

  • In-pouch test / PCR

• • Serology

  • Giardia SNAP test

  • Parvovirus SNAP test

What imaging can be done for a V and D case?

• Rx

  • To rule out obstruction/ other surgical

• Ultrasound

  • Intussusception

  • Foreign body

• Contrast studies rarely needed

How can you use response to a treatment as a diagnostic test for V and D?

• Discontinuation of drugs or toxins

• Dietary restriction

• Anti-emetics

• Anti-diarrhoeals

• Parasiticides

What emergency diagnostics do you use in a peracute crisis of V and D?

• PCV/total protein (refractometer)

• Examine blood smear

• Blood glucose (glucometer)

• Blood urea (dipstick)

• Urinalysis

• (Electrolytes)

• (Blood gas analysis)

• (ECG)

What are the general ways in which you can treat V and D?

• Usually self limiting

• Treat specific cause if identified

• Maintain hydration

• Contraindicated=Corticosteroids/NSAIDS

• Reassess if persists for >48 hours

How can you maintain hydration in a V and D case?

• Oral rehydration solution (if not vomiting or severely dehydrated)

• Parenteral fluids

When would you restrict GI intake in a V and D case?

• Not appropriate in fragile patients

  • Fasting for a min of 12 hours

  • Followed by frequent feeds

    • Small amounts of bland, low fat food

When should you feed through diarrhoea?

• In younger dogs

• Reduces potential of sepsis

• Speeds recovery

What are the centrally acting anti emetics?

• Maropitant - licensed

• Metoclopramide - licensed

• Chlorpromazine

What are the anticholinergic antiemetics?

• Atropine

• Methylscopolamine

What do you need to rule out before giving an anti emetic?

Obstruction

What is the MOA of maropitant?

• NK1 receptor antagonist

List some examples of gastric mucosal protectants

• Cimetidine (Zitac) now licensed for dogs

  • H₂ receptor antagonist

• Proton pump inhibitor (omeprazole)- not licensed

• Sulcralfate

• Antacids

  • AlOH or MgOH

List some examples of anti diarrhoeals?

• Absorbents/protectants

  • Protect mucosa, bind toxins, bind excess water

• Motility modifiers

  • Slow rate of transit, antisecretory

List some examples of absorbents/ protectants?

• Kaolin-pectin

• Activated charcoal

• Al(OH)₃, Mg trisilicate

• Bismuth subsalicylate

• Montmorillonite (Diarsanyl)

List some antidiarrhoeals that are motility modifiers?

• Diphenoxylate

• Loperamide

• Kaolin / morphine

What are the pros and cons of using antibiotics in a V and D case?

-ve

• Cause dysbiosis (imbalance of gut bacteria)

• Cause diarrhoea

+ve

• Could already have dysbiosis

• Risk of sepsis if mucosal barrier is compromised

When are antibiotics indicated in a V and D case?

• Haemorrhagic diarrhoea if concerned about sepsis

• Diarrhoea + pyrexia

• Known infection -

  • Salmonella - only if systemically ill

  • Campylobacter, pathogenic E. coli, clostridia etc - Not needed

• Neutropenic animals

What antibiotic should you not use in a V and D case?

Neomycin

How do you remove a fb?

• Induction of vomiting (only if smotth and non corrosive poison)

• Natural passage

• Surgery

List the specific causes of acute gastroenteritis

What animals are more predisposed to AHDS/HGE?

• All ages

• Toy and miniature breeds

What clinical signs are associated with AHDS?

• Sudden onset of vomition ± blood

• May precede diarrhoea by a few hours

• Severe bloody diarrhoea

• Marked haemoconcentration

  • Elevation of 60-80

• Skin turgor is usually normal

• Depression

• Shock

How do you treat AHDS?

• FLUID THERAPY

• Withhold all food and water

• Parenteral broad spectrum antibiotics

• Protectants

• Anti emetics or anti diarrhoeal?

What is the prognosis for AHDS?

• If untreated

  • Death rapid from shock and circulatory failure

• If treated

  • Mortality low

  • Some dogs have repeat episodes