Diarrhoea and Treatment Flashcards
Give 4 differential diagnoses for an adult horse with acute diarrhoea
Salmonella spp.
Clostridium difficile
Clostridium perfringens
Coronavirus
Cyathostomiasis
Antimicrobial associated
Right Dorsal Colitis
Grain overload
Dietary
Give 4 clinical signs/conditions which may accompany diarrhoea in the adult horse
Quiet to depressed
Colic
Pyrexia
Hypovolaemia
SIRS
Laminitis
Secondary infections
What is the most important thing to inform the clients about a Salmonella spp. infection in their horse?
Some serovars are zoonotic
What are the limitations of PCR testing for Salmonella in faeces?
Can be intermittently spread, so a negative result doesn’t always mean the horse is clear
True or False?
Coronaviruses are part of the normal flora in all ages of horse
False - clostridiosis is part of the normal flora
How do clostridia cause disease?
Toxins produced cause disease - low numbers don’t produce toxins
True or False?
Coronavirus has only recently been found as an enteric pathogen
True
Can be associated with outbreaks
Risk factors not fully understood
What is the most important equine parasitic disease?
Cyathostomiasis
Can have severe clinical signs
Pre-patent disease
Most commonly seen in spring with a sudden mass emergence
Describe the pathogenesis of antibiotics causing colitis
- Disruption of GI flora
- Lack of competition for nutrient
- Pathogenic bacteria able to proliferate
Obligate anaerobe population of the flora is most important, so antibiotics affecting these are more likely to cause diarrhoea
What causes Right Dorsal Colitis?
NSAID toxicity
Describe how grain overload can result in diarrhoea
- Small intestine is overwhelmed and soluble CHO enters the large intestine
- Rapid fermentation by lactic acid-producing bacteria lowers the pH
- Gram negative bacteria die and endotoxins released
- Other bacteria overgrow = gut compromised
- Bacteria and toxins enter the circulation
Other than gastrointestinal disease and antimicrobials, what are the risk factors for diarrhoea in an adult horse?
Immunosuppression
General anaesthesia
Recent abdominal surgery
Hospitalisation
Other horses with diarrhoea
Dietary changes
Which 4 causes of acute diarrhoea can also cause chronic diarrhoea in the adult horse?
Salmonella spp.
Cyathostomiasis
Diet
Right Dorsal Colitis
Name 3 causes of chronic diarrhoea in the adult horse
Salmonella spp.
Cyathostomiasis
Right Dorsal Colitis
Sand enteropathy
Inflammatory Bowel Disease
Dietary
Is ventral oedema more likely to be seen in chronic or acute diarrhoea in the adult horse?
Chronic diarrhoea
What might you see on blood testing an adult horse with chronic diarrhoea?
Electrolytes imbalances
Often normovolaemic
How does sand cause chronic diarrhoea in adult horses?
Accumulates in the large intesting and irritates the mucosa
Often associates with acute intestinal obstruction (colic)
What are 3 risk factors for chronic diarrhoea caused by sand in adult horses?
Pasture access on sandy soil
Overgrazed pastures
Fed on the ground
What are the 4 causes of inflammatory bowel disease in adult horses?
Multisystemic Eosinophilic Epitheliotropic Disease (MEED)
Granulomatous enteritis
Lymphocytic plasmocytic enteritis/colitis
Lymphosarcoma
What is the most frequently found serovar of Salmonella causing diarrhoea in adult horses?
Typhimurium
Common to have a large volume of watery diarrhoea - bacteraemia
Intermittent shedding
What are 4 risk factors for Salmonellosis in adult horses?
Recent abdominal surgery
General anaesthesia
GI disease (small colon impaction)
High ambient temperatures
Prolonged hospital stay
Immunosuppression
Antimicrobials
Horses actively shedding or carriers
What are the most common reasons for clostridiosis in adult horses?
Antimicrobial-associated
Nosocomial (picked up in a hospital)
Part of the normal flora in all ages
Colostridium difficile and Colostridium perfringens
Which types of Clostridium perfringens are most commonly found in adult horses?
Types A and C
Produce toxins which cause disease
Is Clostridium perfringens or Clostridium difficile more likely to be seen in neonates?
Clostridium perfringens
Which Clostridium disease is more likely if the horse has haemorrhagic diarrhoea?
Clostridia perfringens
Which Clostridium disease is most often associated with antimicrobial associated colitis?
Clostridium difficile
Can be zoonotic
Name 3 risk factors for Clostridiosis in adult horses
Dietary changes
Hospitalisation
Antimicrobials
Gastrointestinal disease
In hot climates, when is Cyathostomiasis most commonly seen?
In Autumn - Spring in cooler climates
How long is the pre-patent period of Cyathostomins?
6-14 weeks
Can remain encysted from weeks to 2 years
What stage of the Cyathostomin lifestyle is unaffected by most anthelmintics?
Encysted, hypobiotic larvae
What pathology do Cyathostomins cause in the GIT in an outbreak?
Mucosal injury
Ulceration
Inflammation
What are the risk factors for Cyathostomiasis in adult horses?
Age
Season
Time since last anthelmintic
Altered host immunity
Stress
Dietary changes
Unknown factors