Lead Toxicity in Cats
Lead poisoning in cats is a medical condition caused by increased levels of metal lead in the blood. Lead has the ability to disrupt and damage normal cell functions and may affect multiple systems throughout the body. One of the ways in which lead can adversely affect the body is by displacing and substituting calcium and zinc in the body, both of which are important for normal cell metabolism. Lead toxicity can lead to death if the cat is not treated in time.
A large number of lead sources has been described, and the type of these sources may vary by different geographical locations. Older homes and buildings are frequently potential sources of lead, as lead dust or chips from older lead paints increase the chance of exposure. Fortunately, lead toxicity is not commonly seen in cats, especially as compared to dogs.
Symptoms and Types
The symptoms for lead poisoning mostly relate with the gastrointestinal (GI) and central nervous system (CNS). GI systems, for example, are seen with chronic and low-level exposure, whereas CNS symptoms are more common in acute exposure in young animals. Some of the more common symptoms include:
- Poor appetite
- Abdominal pain
- Regurgitation (due to megaesophagus)
- Hysteria (panicky and anxious)
- Vestibular abnormalities, including nystagmus (rolling eyes) and ataxia, as if the cat is dizzy
- Ingestion of lead – sources can include paint chips, car batteries, solder, plumbing material, lubricating material, lead foil, golf balls, or any other material containing lead
- Use of improperly glazed ceramic food or water dish
- Lead paint and lead-contaminated dust or soil are the most common sources
- Lead-contaminated water
You will need to give a thorough history of your cat’s health leading up to the onset of symptoms, including a history of any contact with material containing lead, if possible. After recording your cat’s history, your veterinarian will perform a complete physical examination. Laboratory tests will include complete blood count, biochemistry profile, and urinalysis -- the results of which may reveal valuable information for initial diagnosis.
Blood testing may reveal red blood cells of unequal size (anisocytosis), abnormally shaped red blood cells (poikilocytosis), variations in red blood cell coloring (polychromasia, hypochromasia), and increased number of neutrophils (a type of white blood cell) may be seen. Urinalysis results are often non-specific; in some patients abnormal concentrations of glucose may be found in the urine.
If your cat is showing all of the appearances of lead poisoning, your doctor will use more specific tests available which will help your veterinarian to determine the levels of lead in both blood and body tissues.
Lead poisoning should be considered an emergency that requires immediate care. Often, chelation therapy -- a detoxifying therapy whereby chelating agents are given through the mouth to bind the lead found in the gastrointestinal system and prevent further absorption -- is the first course of treatment. There are many types of chelating agent available for various types of poisonings, and selection of chelating agent will be made by the attending veterinarian.
Your veterinarian may also perform a gastric lavage to remove and clean the stomach contents if the lead has been ingested within hours of medical care. This method uses water to wash, clean and empty the stomach cavity and digestive tract of poison.
There are also some drugs available which can assist in lowering the body load of lead, especially in cases where concentrations of lead in the blood stream are very high. Your cat's other symptoms will be treated accordingly.
Living and Management
Most cats recover within 24 to 48 hours after initial treatment. Prognosis in affected animals is positive if treated quickly; however, cats with uncontrolled seizures have a more guarded prognosis.
Because humans and other animals are at risk from the same source of lead, your veterinarian is required to report the incident to relevant authorities. You may need to identify the source of lead to prevent further human or animal exposure. If source of lead is not identified and eliminated, future episodes are not uncommon and may pose greater risks.
Prevent human as well as animal exposure to any source of lead. Remove materials that contain lead from easy access (car batteries, plumbing materials, paint), and place objects containing lead in enclosed or hard to reach places (such as lead based dish ware that is antique or intended for decoration only) to prevent any exposure in future. If you live in an old home (esp. previous to 1950), you might consider having the underlying layers of paint checked for lead content, following up with ways to contain the lead. Plumbing is another potential source of lead, as old pipes become corroded over time, leaching lead into the water as it passes through the pipes. The ground soil surrounding the home can also be dangerously high in lead content. As old paint from homes and buildings can leach into the ground over time as the paint deteriorates.