Page 303 - Problem-Based Feline Medicine

16 – THE CAT WITH ACUTE DEPRESSION, ANOREXIA OR DEHYDRATION 295

Differential diagnosis serum phosphorus level < 0.3–0.5 mmol/L, but has
occurred at higher levels.
Other causes of depression and anorexia.
Diagnosis
Treatment
Serum phosphorus level < 0.8 mmol/L.
Provide a thermoneutral environment.
Ruling out other causes of depression, weakness,
Place food in withdrawal location.
anorexia and hemolysis.
Prognosis Differential diagnosis

This is usually a short-term problem with no adverse
Other causes of depression, weakness and anorexia
consequences.
related to the primary disorder.
HYPOPHOSPHATEMIA* Treatment

Classical signs Intravenous potassium phosphate or sodium phos-
phate. See Diabetic ketoacidosis in The Cat With
● Weakness.
Polyuria and Polydipsia (page 236).
● Pallor and hemoglobinuria (hemolysis).
Transfusion with fresh red blood cells if hemolysis
occurs.
Pathogenesis
Prognosis
Hypophosphatemia results from insufficient phospho-
rus intake and/or excessive urinary phosphorus loss The prognosis for correction of hypophosphatemia is
and/or translocation from extracellular to intracellular good and overall prognosis is determined by the under-
fluid. lying disorder.

Mild to moderate hypophosphatemia (serum phospho-
rus level 0.5–0.8 mmol/L) may be seen in numerous HYPOPARATHYROIDISM*
disorders where anorexia is a feature. It is seen most
often with hepatic lipidosis and chronic renal failure. Classical signs
Anorexia may contribute to hypophosphatemia, which
● Anorexia and depression.
in turn may exacerbate anorexia and depression.
● Muscle tremors and seizures.
Severe hypophosphatemia (serum phosphorus level < ● History of thyroidectomy.
0.5 mmol/L) is most likely to be seen in the treatment
of diabetic ketoacidosis and within 3 days of initiating
tube feeding in an anorexic cat. Clinical signs
Anorexia and depression are consistent findings.
Clinical signs
Muscle tremors have been reported in 83%, and seizures
Lethargy, muscle weakness, anorexia – increasing in 50%, of cases of idiopathic hypoparathyroidism.
risk with decreasing phosphorus level.
Severe muscle weakness may lead to respiratory mus- Diagnosis
cle failure (rare).
Hypocalcemia (serum calcium level usually < 1.6
Pale mucous membranes, hemoglobinemia and hemo- mmol/L in the presence of normal serum albumin
globinuria from hemolysis – most likely to occur with level) and hyperphosphatemia.