Diarrhoea Flashcards
Is diarrhoea in the neonate indicative of SI or LI disease?
LI
Is diarrhoea in the juvenile/adult indicative of SI or LI disease?
LI
What age are foals commonly weaned?
6 months
What age do foals begin eating roughage?
Towards 6 weeks (end of neonatal period)
Infectious causes of diarrhoea in the neonatal foal between 0 and 10 days of age
Viral: Rotavirus, Coronavirus (usually immunocompromised)
Gram +ve: Clostridium spp.
Gram -ve: E. coli, Salmonella spp., Actinobacillus spp.
Fungal (immunocompromised): Candida, Mucor
Protozoal: Cryptosporidium
Additional infectious causes of diarrhoea in neonatal foals 10 days to 6 weeks (majority same as 0-10 days)
Gram +ve: Rhodococcus equi (uncommon)
Parasites: Strongyloides westerii, Parascaris equorum, Strongylus vulgaris
How are neonates infected with Strongyloides westerii?
Through mares milk
Non-infectious causes of diarrhoea from 0-10 days
Foal heat diarrhoea
Secondary to meconium impaction
Errors in feeding (concentration/volume, particularly if orphaned)
Gastroduodenal ulceration
Sand enterocolitis
Systemic disease (sepsis, perinatal asphyxia syndrome/neonatal maladjustment syndrome)
Congenital lactose intolerance
Non-infectious causes of diarrhoea in foals 10 days to 6 weeks
Foal heat diarrhoea (<2w)
Secondary to meconium impaction
Errors in feeding (concentration/volume, post enteritis lactose intolerance)
Gastric ulceration
Sand enterocolitis
Antibiotic induced diarrhoea (oral)
Treatment of diarrhoea in the neonate
Underlying cause?
Consequences (fluid/electrolyte loss, bacterial translocation, albumin loss, nutrition)
Problem with providing nutrition in neonatal diarrhoea
Decreased absorption of nutrients = enteral rest/starving required
Must provide nutrition another way
Risk factors for developing GI disease in the neonate
Failure of passive transfer
Pre-existing disease
Poor hygiene in peripartum period
High stocking density
Antimicrobial administration
Milk replacer therapy
Clinical signs of acute diarrhoea in the juvenile/adult horse
Cow pat to high volume/hosepipe D+++
Quiet/depressed
Colic
Fever
Hypovolaemia
SIRS
Laminitis
Secondary infection
Infectious causes of acute diarrhoea in the young horse
Salmonella spp.
C. difficile
C. perfringens
Coronavirus
Cyathostomiasis
Lawsonia intracellularis
(Rhodococcus equi)
What pathogen causes equine proliferative enteropathy (thickened small intestine on ultrasound scan)?
Lawsonia intracellularis bacteria
What signs are seen with equine proliferative enteropathy?
Severe hypoalbuminaemia
Weight loss +++
Causes of chronic diarrhoea in the juvenile horse
Salmonella spp.
Cyathostomiasis
Right dorsal colitis
Sand enteropathy
Inflammatory bowel disease
Dietary
Lawsonia intracellularis
Rhodococcus equi
Which two causes of diarrhoea in the juvenile horse have increased risk geographically and on farms with history of disease/annual reoccurrence?
Lawsonia
R. equi
Diarrhoea is an incommon manifestation of Rhodococcus equi; what does it usually cause?
Respiratory disease
Risk factors for developing diarrhoea in the juvenile/adult horse
Gastrointestinal disease
Immunosuppression
Antimicrobials
General anaesthesia
Recent abdominal surgery
Hospitalisation
Other horses
Dietary change
Key consideration with diarrhoea cases
Isolation is necessary as it is difficult to rule infectious cause in/out
Clinical signs of chronic diarrhoea in the adult horse (compared with acute)
Cow pat to D+++ (not hosepipe)
Bright to depressed
Colic
Fever
Ventral oedema (albumin loss causes decrease in oncotic pressure)
Weight loss
Electrolyte imbalances
Often normovolaemic
Do horses have a risk of deteriorating rapidly with acute or chronic diarrhoea?
Acute
Causes of acute diarrhoea in the adult horse
Salmonella spp.
Clostridiosis
Coronavirus
Cyathostomiasis
Antimicrobial
Right dorsal colitis
Grain (carbohydrate) overload
Dietary
Nosocomial bacteria which causes large volume watery diarrhoea and is intermittently shed. Can also cause bacteraemia
Salmonella
What bacterial infection in the adult horse develops following antimicrobials?
Clostridiosis
Nosocomial
Comes from a hospital
Is C. difficile or C. perfringens a more common cause of diarrhoea?
C. difficile
Clostridium that can cause large volume haemorrhagic diarrhoea in the horse (mainly neonates, also adults)
C. perfringens (type A and C more common)
Most important equine parasitic disease
Cyathostomiasis
When is cyathostomiasis most commonly seen?
Spring
Life cycle of cyathostomes
PPP 6-14w
Can remain encysted from weeks to 2y
Encysted hypobiotic larvae unaffected by most anthelmintics
IL3 emerge in Spring, many at once (clinical disease)
Why do antimicrobials cause colitis?
Disrupt GI flora
Lack of competition for nutrients
Pathogenic bacteria proliferate
Which antibiotics have a higher likelihood of causing antimicrobial associated colitis?
Antibiotics affecting anaerobes because obligate anaerobe population of the flora is most important
Cause of right dorsal colitis
NSAIDs
How does grain overload cause diarrhoea/SIRS/laminitis?
SI digestion overwhelmed so soluble carbohydrates (CHO) enter LI
Rapid fermentation by lactic acid producing bacteria lowers pH so gram negative bacteria die and endotoxins released
Lactic acid poorly absorbed = osmotic diarrhoea
Other bacteria overgrow and gut wall becomes compromised so bacteria and toxins enter circulation
Causes of chronic diarrhoea
Salmonellosis
Cyathostomiasis
Right dorsal colitis
Sand enteropathy
Inflammatory bowel disease
Dietary (dietary imbalance/change in diet/change in flora)
Most frequently isolated Salmonella spp.
Typhimurium
Chronic diarrhoea caused by cyathostomiasis
Affects colon wall
Milder than acute disease
Sand enteropathy
Abnormal accumulation of sand in the large intestine causing diarrhoea (often associated with acute intestinal obstruction)
Causes of inflammatory bowel disease (4)
Multisystemic eosinophilic epitheliotropic disease/MEED
Granulomatous enteritis
Lymphocytic/plasmocytic enteritis/colitis
Lymphosarcoma
Aim of diagnostics in diarrhoea
Determine likely cause
Determine need for supportive therapy
Determine need for specific therapy
Determine risk to in-contact horses and personnel
Treatment of acute diarrhoea
Fluid replacement and electrolytes
Anti-inflammatories
Analgesia
Antimicrobials
Adsorbents
Nutrition
Specific therapy
Fluid replacement for mild/moderate diarrhoea
Voluntary drinking +/- NGT
Fluid replacement for moderate/severe diarrhoea
Hartmanns
Why must a fluid bolus not be given quickly to a horse with diarrhoea?
Loss of albumin = decreased oncotic pressure
Increased risk of oedema if bolus given too quickly
Electrolytes advised in horses with diarrhoea
Many: KCl
Some: NaHCO3 or Na
Analgesia for diarrhoea
Flunixin meglumine?
Temporary relief: xylazine/detomidine +/- butorphanol
CRI for severe pain: butorphanol, lidocaine +/- ketamine
Antimicrobial choice in horse with diarrhoea that is neutropaenic or showing signs of sepsis (secondary infections)
Penicillin IM and Gentamycin IV
Antimicrobial for horse with Clostridiosis
Metranidazole PO
Best probiotics in horses
Faecal transfaunation via NGT from horse that hasn’t had antimicrobials/no other infection
Adsorbent used in horses with diarrhoea
Di-Tri Octahedral Smectitie (Biosponge) given SID/BID via NGT
Nutrition for horse with diarrhoea
Ideally complete pelleted diet (no grain/hay)
Inappetent: good quality grass/hay/anything
Corn oil for added calories
Specific therapy for right dorsal colitis
Misoprostol
Psylium
Specific therapy for cyathostomiasis
Anthelmintics (Moxidectin)
Pre-treatment with steroids as inflammation expected (dexamethasone/prednisolone)
Specific therapy for sand enteropathy
Psyllium
Specific therapy for L. intracellularis
Doxycycline
Management of sepsis in acute diarrhoea
Circulatory support (fluids +/- dobutamine)
Flunixin (block parts of sepsis cascade)
Cryotherapy (reduce laminitis)
Plasma? (Expensive to make a difference to protein levels)
Pentocyfyline? (Suppress pro-inflammatory cytokines?)
Polymixin B? (Prevents initiation of pro-inflammatory cascade?)
Treatment of diarrhoea in the neonate
IVFT (care with sodium/acid base balance)
Antimicrobials (FPT/sepsis)
GI rest (PPN/TPN)
Factors that indicate isolation is needed in diarrhoea
2 out of 3
Pyrexia
Neutropaenia
Diarrhoea
