VPT 421: Veterinary Toxicology (2+0)

DIAGNOSIS

• Diagnosis is based on history, clinical symptoms, post mortem lesions and presence of a source of lead and the lead content of the blood and faeces in a living animal.
• Measurement of ALA dehyratase in blood.
• Urine δ ALA is increased. Level of lead >4 ppm in the liver, 0.2 ppm in whole blood indicates lead poisoning.
• Twice these levels are fatal. Nucleated RBS and basophilic stippling are associated with lead poisoning in dogs. (These are also noticed in autoimmune haemolytic anaemia).

Differential diagnosis

• The symptoms of lead poisoning especially the nervous symptoms resemble the symptoms exhibited in other conditions like hypomagnesemic tetany, nervous form of acetonaemia, tetanus, vitamin A deficiency, listeriosis, barley poisoning, brain abscess or neoplasia and encephalitis.
• In dogs differential diagnosis should be with acute pancreatitis, hepatitis, intestinal parasiticism, heat stroke, encephalitis, rabies and distemper.