Page 839 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

814 CHAPTER 4

VetBooks.ir 4.141 administered drugs to the small intestine. If gastric
emptying is delayed, bethanecol (0.025–0.10 mg/kg
s/c q6–8 h or 0.3–0.4 mg/kg p/o q6–8 h) or metoclo-
pramide (0.05– 0.25 mg/kg s/c q6–8 h or 0.6 mg/kg
p/o q4 h) may be useful.

Prognosis
The prognosis is variable, depending on the degree
of duodenal damage (Fig. 4.142). Duodenal stric-
ture carries a guarded prognosis. Peritonitis
from a perforating duodenal ulcer carries a grave
prognosis.

LAWSONIA INTRACELLULARIS INFECTION
(PROLIFERATIVE ENTEROPATHY)

Definition/overview
Also known as proliferative enteropathy, Lawsonia
Fig. 4.141 Endoscopic view of a normal duodenum.
intracellularis infection is as an important disease in
foals and is occasionally seen in older horses.
Management
Suppression of gastric acidity is the main treatment. Aetiology/pathophysiology
This can be achieved by a variety of drugs (Table 4.7). L. intracellularis is an obligate intracellular organ-
Omeprazole appears to be the most effective available ism that can cause proliferative enteropathy in
drug, but systemic administration should be consid- a number of species, particularly pigs. Infection
ered due to variable absorption of oral formulations, with L. intracellularis is via the faecal–oral route;
especially where delayed gastric emptying may be however, the source of infection is typically not
present. Concurrent treatment with sucralfate is indi- identified. Following ingestion, the organism
cated. The required duration of treatment is unclear, invades enterocytes, particularly in the jeju-
although a minimum of 1 month is usually indicated. num and ileum, and affected cells proliferate
Ensuring proper gastric emptying is important causing hyperplasia (Fig. 4.143). The complete
for decreasing secondary EGUS and for delivering pathophysiology is not understood. The large

4.142 4.143

Fig. 4.142 Multifocal erosions of the duodenal Fig. 4.143 Mucosal surface of the ileum of a 6-month-
mucosa. old foal with Lawsonia intracellularis infection. Note the
thickened, corrugated mucosa.