What is Lockjaw?
Cats are more resistant to the tetanus neurotoxin than other mammals, giving them a longer incubation period than is typical. Because of this, cats often develop localized tetanus rather than generalized. Lockjaw is a serious medical condition that requires immediate treatment in order to save the cat's life.
Lockjaw, also known as tetanus toxemia, is a condition that is caused by Clostridium tetani, a neurotoxin that resides in necrotic tissue, soil, and other low oxygen environments. The neurotoxin is marked by its ability to live for long periods of time in areas with low oxygen by producing spores. When a cat comes into contact with these spores, they enter the cat's body and bind to the nerve cells, causing muscle spasms and muscle stiffening.
Symptoms of Lockjaw in Cats
Depending on how many spores were able to enter the cat's body and the quantity of toxins produced by the cat, symptoms may range from mild to severe. These symptoms include:
- Rigid muscles at entrance site, which is typically a wound or bite mark
- Stiff jaw and neck muscles
- Uncoordinated gait
- Pain during urination
- Mouth upright in a "grin"
- Hard, stiff tail
- Stiff ears that are continually erect
- Breathing problems
- Difficulty with eating
- Painful sensitivity to touch
- Difficulty in opening mouth
- Whole-body spasms triggered by a sudden noise or movement
- Drawn-back lips
- Whole-body paralysis
There are two types of lockjaw:
- Localized: Neurotoxins just affect the nerve cells in the area around the entrance site/wound
- Generalized: Neurotoxins enter the site and spread through the nerve cells throughout the body
Causes of Lockjaw in Cats
The tetanus spores enter the cat's body through a previously acquired wound, where they germinate. Cats with deep puncture wounds are at a greater risk of contracting the spores. Once the tetanus spores enter the body, they bind to the nerve cells and block the regular transmission of nerve signals. This causes muscle stiffness and spasms to occur. Because the neurotoxin dwells in soil and the dead tissue of animals, outdoor cats are most at risk.
Diagnosis of Lockjaw in Cats
The veterinarian will need to know the cat's health history, any recent wounds or injuries, and a complete list of symptoms. The veterinarian will examine the cat, gently feeling for muscle stiffness, looking at the cat's gait and listening to the cat's lungs for any signs of breathing difficulty.
Routine laboratory tests will be performed, which include a complete blood count and a biochemical profile. These tests may show signs of infection with the presence of high or low white blood cells and the presence of creatine phosphokinase, an enzyme that increases in response to the bacterial infection. A urinalysis may also be ordered that could indicate the presence a myoglobin, a muscle protein that passes into the urine from the damaged muscles. To confirm the diagnosis of tetanus, the veterinarian will take a small sample of the fluid and tissue at the wound site. These samples will be sent to the lab for analysis.
Treatment of Lockjaw in Cats
If the tetanus is generalized, the cat will need to be hospitalized in order to receive constant care during the critical stages of treatment. Hospitalization will be necessary for three to four weeks.
Cats that are unable to open their mouths will have a feeding tube placed in order to get the nutrients and calories they need. This feeding tube will either be inserted through the nose (naso-gastric) or directly into the esophagus via a small incision in the neck (naso-esophageal). The feeding tube will remain in place until the cat is able to eat on its own.
Cats who aren't getting enough oxygen on their own due to muscle stiffness will be given oxygen through a nose cannula or face mask. If the muscles are too stiff to move, a breathing tube may be inserted into the cat's trachea in order to get the cat the oxygen it needs.
If the cat is dehydrated, fluids will be administered intravenously. The cat's heart and lungs will be monitored during fluid therapy to ensure they are receptive to the fluid intake.
Several medications may be prescribed to the cat in order to treat lockjaw. A tetanus antitoxin will be given in order to bind the toxin and prevent it from affecting more nerve cells. Antibiotics will be prescribed to kill the tetanus bacteria. Muscle relaxers will be given to relieve muscle stiffness and pain. Tranquilizers may also be prescribed in order to help the cat rest, promote healing and reduce muscle spasms and stiffness.
The original wound must be drained of any pus and cleaned thoroughly. Topical antibiotics may also be prescribed in order to discourage the growth of spores and promote healing.
Recovery of Lockjaw in Cats
At home, the cat will need to be placed in a low-light environment that is quiet. Because loud noises and stress can cause muscle spasms to occur, it's important to remove other animals and young children from the cat's area. Provide soft bedding in order for the cat to be comfortable while it rests. The cat will need to remain immobile while it recovers, so it's important to follow the veterinarian's instructions to care for the cat at home, including changing its position every few hours to prevent ulcers and bedsores from forming. The veterinarian will need to follow up with the cat to monitor its healing and progress. When lockjaw is treated promptly, the prognosis is good and most cats fully recover.