Reply To: Pyrexia Case

Lameness has many causes, but due to the multiple joint effusions the differentials focused on causes of non-traumatic inflammatory joint disease. Degenerative joint disease was a consideration (but thought less likely due to age), but more likely septic or immune-mediated (erosive and non-erosive) polyarthritis.

It is always important to distinguish between hyperthermia and pyrexia.

Increased body temperature may be a result of pyrexia caused by infectious agents (bacteria, protozoa, fungae and parasites), immune-mediated disease, neoplasia, non-septic inflammation, tissue damage, necrosis, pharmacological agents (e.g. colchicine and bleomycin) and idiopathic pyrexia. Causes of hyperthermia; inadequate heat dissipation (heat stroke, hyperpyrexic syndromes), exercise hyperthermia (normal exercise, seizure disorders) and pathologic or pharmacological origin (lesions of the anterior hypothalamus, malignant hyperthermia, hypermetabolic disorders).

No access to pharmacological agents was reported. Heat stroke, seizure disorders and malignant hyperthermia were excluded as there was no history of exposure to strenuous exercise, history of seizures or administration of halogenated anaesthetics or depolarising agents. Lesions of the hypothalamus and hypermetabolic disorders could not completely ruled out.

Pyrexia was thought to be more likely as the dog did not seem to attempt to dissipate heat and was most likely to be related to the joint effusions at this stage.

What initial treatment and investigations would you consider?

Scott x