Categories: diary
      Date: Feb 18, 2010
     Title: Rare tetanus case

Rare tetanus case

            I think that you would probably agree that three cases in fifteen years of vetting constitute a rare condition, though in its nature it is once seen, never forgotten. As soon as the dog walked through the door, I could see from its rather extraordinary appearance that we were most likely dealing with canine tetanus.

            With ears raised and a fixed expression of surprise the normally chilled yellow retriever looked like she had just had “Botox” treatment. Coupled with a rapidly stiffening gait, raised rigid tail and the recent history of an infected toe all the evidence pointed towards a rocky road ahead.

            In fact it is quite difficult to specifically diagnose tetanus; ambiguous blood tests usually providing results too late in the day to encourage evidence based treatment. However, the clinical signs are significantly unusual to allow a presumptive diagnosis and emergency treatment can be started straight away.

            The condition is caused by a toxin released from spores produced by the bacteria Clostridium tetani that lie dormant in the environment and become active when contaminating a wound. It is often the facial muscles that are affected first, giving the patient their distinctive expression, but as the toxin circulates around the body all muscles succumb. Affected animals suffer a rigid paralysis and are often unable to swallow making them very difficult patients to treat.

            Treatment can be broken into two phases. Initially, the priority is to deal with the infected wound, which in this case meant amputation of the toe. Powerful intravenous antibiotics also counteract the spread of infection. We also have to neutralize the chemicals released from the clostridium spores by injecting large quantities of tetanus anti-toxin; more normally used in horses that are far more susceptible to the disease. This in itself is not without problems, as the drug can induce anaphylactic reactions; though fortunately not with our patient.

            After this it is just a matter of time and patient nursing for up to two weeks as the toxin is metabolised from the system. To help this we placed a tube that passes through the body wall directly into the stomach to allow feeding, and a urinary catheter to facilitate emptying of the bladder. As you might imagine, being in a permanent state of muscle spasm and contraction is quite exhausting and so patients are often sedated.

            All in all, this adds up to a patient that requires a huge amount of intensive nursing and veterinary care and last weekend this was provided by Laura, whose dedication and conscientious approach has undoubtedly helped the unfortunate dog turn the corner. Though not out of the woods yet, she is now able to get back onto her feet and move around, still rather stiffly, but a significant improvement none the less. As this week has progressed the signs have continued to be good and though she is still requiring intensive nursing, we are hopeful that she has been through the worst. Of the two cases that I have seen previously we have a fifty percent success rate,

            As already mentioned, tetanus is a disease that we don’t often see, particularly in dogs. Some species seem to be more susceptible to the disease and consequently, like humans, are vaccinated, however, because of its rarity in dogs, it is not considered necessary. It is surprising, however, that in the absence of vaccination how the most innocuous looking minor wound can result in such severe disease.