Clinical signs of hypocalcaemia reflect calcium’s importance to the electrical stability of excitable tissue. Spasms, cramp and tetany are commonly observed. Handling and excitement typically induce or worsen the signs. Onset is sudden and dramatic and may follow a period of non-specific illness comprising lameness, stiffness, pain, nervousness, panting, lethargy, weakness, inappetance and fever. Total serum calcium may not reflect the low ionized calcium and the latter should always be specifically checked. The neuromuscular signs may be episodic despite a persistent hypocalcaemia. Diagnosis: ionized serum calcium <1.0 mmol/l.
The muscle spasms are often painful (cramp). Rigid abdominal muscles and pain induced by palpation of the spinal epaxial muscles may be confused with spinal pain from IVDD, discospondylitis, etc. Pancreatitis may be an equally erroneous conclusion.
Ear and facial twitching may occur. Elevated third eyelids are reported in the cat. Intense facial rubbing occurs in cats and is seen in over 50% of dogs. Intense biting or licking of the paws is another manifestation of what may be a paraesthesia. Humans report numbness and tingling of the fingers, feet and the perioral area.
The dog had been quiet and depressed for months and was inappetant. Vomiting had been intermittent. Painful episodes had occurred in the week prior to presentation. NSAID administration had not improved the dog’s condition. The dog had been referred for treatment of suspected IUD disease.