Weight loss- Intestinal causes

Question 1

List the 5 pathophysiological mechanisms of weight loss

Answer 1

decreased dietary intake
increased rate of utilisation
loss of nutrients (malabsorption/ maldigestion)
Inadequate delivery to tissues
Conditions that cause muscle wasting

Question 2

what is the most common pathophysiological cause of weight loss in horses

Answer 2

loss of nutrients (malabsorption/ maldigestion)

Question 3

List the 3 types of Chronic inflammatory bowel disease (CIBD) in horses

Answer 3

Granulomatous enteritis
Eosinophilic enterocolitis
Lymphocytic-plasmacytic enterocolitis

Question 4

List 3 small intestinal causes of weight loss in horses

Answer 4

Chronic inflammatory bowel disease (CIBD)
Proliferative enteropathy
alimentary tract neoplasias

Question 5

Describe granulomatous enteritis

Answer 5

characterised by lymphoid and macrophage infiltration of the lamina propria
leads to villous atrophy

Question 6

what causes granulomatous enteritis

Answer 6

unknown
think it may be to do with inflammatory reaction to intestinal bacteria

Question 7

describe eosinophilic enterocolitis

Answer 7

eosinophilic infiltration of intestinal mucosa
There are 3 types= MEED, DEE, IFEE

Question 8

Describe MEED

Answer 8

Multisystemic eosinophilic epitheliotrophic disease
other organs involved

Question 9

describe DEE

Answer 9

diffuse eosinophilic enterocolitis
affects all small and large intestine

Question 10

Describe IFEE or IFEC

Answer 10

idiopathic focal eosinophilic enteritis/ colitis
segmental small or large intestinal lesions present

Question 11

what causes esoinophilic enterocolitis

Answer 11

Unknown
thought to be related to nematode infestation

Question 12

what breeds is eosinophilic enterocolitis most common in

Answer 12

young thoroughbreds and standardbreds

Question 13

describe lymphocytic-plasmacytic enterocolitis

Answer 13

lymphocyte and plasma cells infiltration lamina propria

Question 14

what causes lymphocytic-plasmacytic enterocolitis

Answer 14

Unknown
think it precedes the development of intestinal lymphoma

Question 15

what causes proliferative enteropathy

Answer 15

Lawsonia intracellularis - obligate intracellular bacterium

Question 16

what does proliferative enteropathy tend to affect

Answer 16

jejunum and ileum

Question 17

what age does proliferative enteropathy tend to affect

Answer 17

weanling foals between 3-8months

Question 18

List 6 risk factors of proliferative enteropathy

Answer 18

horses in close proximity to swine
overcrowding
feed changes
antibiotic usage
mixing and transportation
weaning

Question 19

List the 4 large intestinal causes of weight loss in horses

Answer 19

parasite infestation- in heavy infestations
right dorsal colitis
sand enteropathy
EEs - eosinophil enterocolitis

Question 20

List 3 Large strongyles that affect large intestine of horses

Answer 20

Strongylus vulgaris - most important
Strongylus edentatus
Strongylus equinus

Question 21

Describe how large strongyles cause disease in horses

Answer 21

4th stage larvae migrate through mucosa/ submucosa
this affects myoelectrical activity
becomes infiltrated with inflammatory cells
–> increased secretion and decreased absorption

Question 22

what does sudden emergence of small strongyles cause

Answer 22

mucosal injury
ulceration
inflammatory reaction

generally due to unknown stimulus

Question 23

describe how small strongyles cause diarrhoea

Answer 23

increased secretions secondary to granulomatous inflammation
disruption to interstitium

Question 24

describe the aetiology of RDC in horses

Answer 24

NSAIDS - particularly Phenylbutazone
especially in horses that receive inappropriately large doses

Question 25

what are the signs of right dorsal ulcerative colitis

Answer 25

intermittent colic
diarrhoea
weight loss

Question 26

Describe sand enteropathy

Answer 26

when horse ingests sand with food- builds up in ventral colon can lead to damage to colonic mucosa –> D+ and weight loss