Page 669 - Problem-Based Feline Medicine

30 – THE CAT WITH SIGNS OF ACUTE VOMITING 661

Hemogram, serum chemistries and urinalysis are typi- Clinical signs
cally unremarkable.
Dysautonomia is generally seen as an acute onset of
Survey radiographs of the abdomen may be normal or depression, anorexia, constipation, dry external
show gastric distension. Contrast radiographs may nares and mouth, reduced tear production or dry
identify hypertrophic gastric mucosa or a narrow eye, bradycardia, regurgitation (due to megaesopha-
gastric outflow pathway (“beak sign”). gus) and dilated pupils.

Ultrasonography may be able to detect a thickened Other clinical signs that may be present, but are less
pyloric antrum. common, include anal areflexia, fecal incontinence,
and dysuria or urinary incontinence.
Fluoroscopy or scintigraphy can be used to evaluate
gastric peristalsis and emptying, but are not universally The disease occurs primarily in Great Britain, but
available. sporadic cases have been reported in the United States
and elsewhere.
Gastric endoscopy may be normal or may reveal
thickened folds of mucosa, the pyloric antrum may Most affected cats are young (< 3 years old) and have
not insufflate normally, or the pylorus may be too no breed or sex predisposition.
stenotic to allow passage of the endoscope through the
orifice.
Diagnosis
Definitive diagnosis requires an exploratory laparo-
In general, routine hemogram, biochemistry tests and
tomy and histopathologic examination of tissue.
urinalysis are within normal limits.
Megaesophagus may be observed on routine thoracic
DYSAUTONOMIA radiographs.
Constipation or obstipation may also be detected on
Classical signs abdominal radiographs.

● Vomiting or regurgitation, diarrhea, Schirmer tear tests will be abnormal (< 5 mm) in
anorexia and constipation are the primary most animals.
GI signs.
Ophthalmic pharmacology testing may be helpful, but
● Dry eyes, mucous membranes and nose
is not 100% reliable in detecting dysautonomia.
may be observed.
However, in dysautonomic cats phospholine iodide will
● Bradycardia.
have no miotic effect, and pilocarpine will have an
● Dilated pupils.
exaggerated miotic effect.
See main reference on page 792 for details (The Low plasma or urinary catecholamine concentrations
Constipated or Straining Cat). also confirms sympathetic insufficiency.

RECOMMENDED READING
August JR. Consultations in Feline Internal Medicine. WB Saunders, Philadelphia, PA. 2001, 4.
Ettinger SW, Feldman EC. Textbook of Veterinary Internal Medicine, 5th edn. WB Saunders, Philadelphia, PA. 2005.
Greene’s Infectious Diseases of Dogs and Cats, 2nd edn. WB Saunders, Philadelphia, PA. 2005.
Kirk’s Current Veterinary Therapy, XIII, 2000.