Page 821 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

796 CHAPTER 4

VetBooks.ir Management lymphocytic–plasmacytic enteritis, eosinophilic
enterocolitis and intestinal lymphosarcoma.
Treatment can be rewarding and the response to
initial treatment is an important prognostic indica-
tor. Initial therapy typically consists of prednisolone Diagnosis
1 mg/kg p/o q24 h for 21 days. An initial positive Hypoproteinaemia, consisting mainly of hypoal-
response to treatment is a good prognostic indica- buminaemia, is common. Anaemia is commonly
tor. Animals that fail to respond to initial treatment present and may be the result of chronic disease or
have a poorer prognosis. Further treatment consists immune-mediated haemolytic anaemia (IMHA).
of systemic dexamethasone. The WBC count is usually normal. Urinalysis and
abdominocentesis are usually normal, although
Prognosis aseptic peritonitis may be present in some cases.
The prognosis is variable. The magnitude of hypo- Abdominal ultrasound examination may be per-
proteinaemia and the response to treatment are formed but is usually unremarkable.
important prognostic indicators. Carbohydrate absorption testing should be per-
formed. Decreased absorption is usually present,
GRANULOMATOUS ENTERITIS except with early disease or focal lesions. Rectal
mucosal biopsy can be diagnostic if disease also
Definition/overview involves the rectum. Surgical biopsy of the ileum has
Granulomatous enteritis is a form of inflammatory the highest diagnostic value. Many cases are only
bowel disease. It is most commonly reported in diagnosed definitively at necropsy.
Standardbred horses and a familial predisposition
has been postulated. Young horses (1–5 years old) are Management
most commonly affected. Treatment is often unrewarding, based on the typi-
cal poor response to treatment and the severity of
Aetiology/pathophysiology disease when the disease is diagnosed or suspected.
The aetiology is unknown, and the pathophysiology is Long-term dexamethasone (40 mg/adult horse i/m
unclear. It is characterised by infiltration of the intesti- q96 h for 4 weeks, then 35 mg/adult horse i/m q96
nal wall with macrophages and epithelioid cells. Villus h for 4 weeks, with continued tapering of dose) has
atrophy subsequently develops, resulting in malab- been reported to be successful in a limited number
sorption and maldigestion. Impaired dietary protein of horses. Parenteral nutrition may be required ini-
absorption and small intestinal mucosal ulceration tially in severely affected animals. Surgical resec-
may contribute to hypoproteinaemia. Lesions are more tion of the affected area is not likely to be practical
common and severe in the small intestine, particularly because a large portion of the intestinal tract is usu-
the ileum. The large colon is less frequently affected. ally involved.

Clinical presentation Prognosis
The most common presenting complaints are weight The prognosis is poor. Most horses are euthanased
loss and anorexia. Oedema may develop, consistent because of poor response to medical treatment and
with the degree of protein loss. Diarrhoea and colic are deterioration of condition.
less commonly observed. Significant small-intestinal
fluid loss can be masked by the absorptive capacity of EOSINOPHILIC ENTEROCOLITIS/
the normal large colon. Attitude is normal initially, but MULTISYSTEMIC EOSINOPHILIC
depression and weakness may develop over time. EPITHELIOTROPIC DISEASE

Differential diagnosis Definition/overview
Other causes of protein loss and weight loss should be Eosinophilic enterocolitis (EE) is an uncommon
considered, including protein-losing nephropathy, form of inflammatory bowel disease. Multisystemic