Page 478 - Problem-Based Feline Medicine

470 PART 7 SICK CAT WITH SPECIFIC SIGNS

Clinical signs HYPERADRENOCORTICISM*

Cats with the intestinal form of tuberculosis (caused by
Mycobacteria tuberculosis, M. bovis, M. tuberculosis- Classical signs
bovis variant, and M. microti) and intestinal involvement
● Polyuria, polydipsia, polyphagia.
with non-tubercular mycobacteria (M. avium complex)
● Abdominal distention, alopecia, fragile skin.
may show signs varying from subclinical infection to
chronic enteritis characterized by weight loss, fever,
See main reference on page 251 for details (The Cat
vomiting, diarrhea and mesenteric lymphadenopathy.
With Polyuria and Polydipsia).
Cats with advanced disease may develop obstructive
ascites. Clinical signs

Many cats with hyperadrenocorticism have diabetes
Diagnosis
mellitus, which causes the polyuria and polydipsia.
Laboratory results are variable, but non-regenerative Polyphagia may be due to both diabetes and hypera-
anemia is common. drenocorticism, and may be severe.
Abdominal radiographs may reveal mesenteric lym- Muscle wasting is due to both disorders. This con-
phadenopathy and peritoneal fluid. Abdominal ultra- tributes to abdominal distention, which is manifested
sonography may reveal intestinal thickening, as a “pot-bellied” appearance, similar to the dog.
mesenteric lymphadenopathy, and peritoneal fluid.
Dermatologic signs include unkempt haircoat, patchy
Lymph nodes may be calcified.
alopecia, and skin that tears and bruises easily.
Peritoneal fluid may presumably be a transudate,
modified transudate, chylous or exudate. Macro- Diagnosis
phages containing acid-fast bacteria may be seen.
Confirmatory testing and distinguishing a pituitary
Cytology and histology of a biopsy of the intestinal tumor from an adrenal tumor is similar to the dog,
tract and mesenteric lymph nodes reveal granuloma- involving urine cortisol:creatinine ratio, ACTH stimu-
tous to pyogranulomatous inflammation. Acid-fast lation test, dexamethasone suppression tests, plasma
bacteria are usually detectable in biopsies. ACTH level, abdominal ultrasonography and CT-scan-
ning or magnetic resonance imaging.
Culture is possible at selected laboratories, but may
take weeks for a positive result.
Differential diagnosis
Differential diagnosis Other causes of insulin-resistant diabetes mellitus.

Differential diagnoses for intestinal tuberculosis Muscle wasting from another chronic disease plus
include alimentary lymphoma, widely metastatic marked obesity or peritoneal fluid can mimic the pot-
tumors, other pyogranulomatous bacterial infections bellied appearance of hyperadrenocorticism.
and systemic fungal infections.
Treatment
Treatment Hypophysectomy and adrenectomy have historically
provided the most consistent results.
Notify public health officials. Euthanasia is often
advised with true tuberculosis because of the zoonotic Trilostane has alleviated clinical signs of pituitary-
risk. If treatment of a mycobacterial infection is dependent hyperadrenocorticism in all reported cases.
attempted, drug doses are provided in references in The
Mitotane and ketoconazole have inconsistent results.
Cat With Non-Healing Wounds and The Cat With
Enlarged Lymph Nodes. Pituitary irradiation has inconsistent results.