Nowadays, Vets and doctors have practically the same diagnostic tools: scanners, magnetic resonance, even DNA tests, are also available for animal patients. All these tools (when properly used), are a valuable help for the Vet, but no one of them can replace or improve a correct “hands off” and “hands on” inspection. The very first thing is to obtain some info about the patient circumstances (age, feeding, etc), and then the Vet proceeds with the classical exploration, which includes visual inspection, palpation and auscultation. Every Vet is qualified for performing this, even in a home visit, which can also include blood and skin sampling. Other diagnostic procedures, such as X-ray and ultrasonography must be performed at the practice. Basic equipment for diagnostics should include X-ray device, ultrasound scanner, seric biochemistry analyser and haematological cell counter.
Normally we start with most basic tests, and in case they are not enough for stablishing a definitive diagnosis, we continue with more sophisticated ones. Recommending a CAT (Computerised Axial Tomography) scanner without taking a simple X-ray first, makes nonsense.
The most important limitation for diagnostic tools is economy. When we go to a human hospital (in a European country, we mean), we are not asked by the doctor how much money do we want to spend, because we don’t pay directly the bill. So, the doctor orders a huge battery of tests for discarding different pathologies. Meanwhile, in Veterinary science, most diagnostic tests are performed, not for discarding but for confirming pathologies, because we must never forget there is no NHS for animals. Apart from the economical factor, we have to consider most sophisticated tests such as CAT scanner or magnetic resonance require the patient must be completely quiet during the procedure, so, as anyone can imagine, in case of an animal patient, implies anaesthetic.
For all these reasons, our first step in image diagnostics is always a simple X-ray and ultrasonography.
In case of blood tests, there are hundreds of brand new genetic test for finding out, for example, if a Labrador have or not the hip dysplasia gen in order to declare it as valid or not valid for reproduction; or maybe if a Persian cat is going to develop polycystic kidney disease; or even the status of the immunity, etc.
Choosing one or another immunological diagnostic tool depends on what we are expecting to find: some of them detect antibodies titre, which allow us to know the degree of immunological response (and in some cases protection) against a disease (or even a vaccine, for example in case of rabies antibodies test). The problem is some diseases may make an animal have a positive titre for life, even if the disease has completely disappeared; some other ones such as PCR (Polymerase Chain Reaction), detect directly the presence or absence of a specific bacterial, viral or parasitic DNA or RNA, which is extremely sensitive, but can fail if the sample is not obtained at the right moment.
So, every individual requires a tailor-made diagnostic protocol.
The Vet must recommend the owner the most useful diagnostic tests in every case. Sometimes the owner would like to perform “all the tests”, but ethically speaking is not acceptable to recommend tests that have very little to do with the case we are investigating just because our hospital have the ultimate (and expensive) device for performing those tests.
We must insist the most powerful diagnostic tool is confidence between owner, Vet and patient.
Liliana Aldeguer Cerdán col 793
English translation by Sergio Reina Esteban col 747
Gran Alacant Exotics
T: 966 698 569