Why should we do more? Many clinicians view the liver as a “black box” that is difficult to understand and which has diseases that are only treated with basic supportive therapy. Hence, they see no reason to do something invasive like a biopsy. Or, perhaps they have been “burned” in the past by doing a biopsy incorrectly or at the wrong time, resulting in therapeutic failure and an upset client (outcomes that they want to avoid ever experiencing again). In fact, a lot of chronic hepatic diseases can be cured or controlled if diagnosed in a timely fashion. However, the only way to definitively diagnose most chronic hepatic diseases is by histopathology. Furthermore, it is extremely rare that a properly performed hepatic biopsy results in morbidity or mortality.

How should we do more? Taking a liver biopsy is central to diagnosis and effective treatment in most canine and feline liver diseases. I explain to the owner that the results of the biopsy will help treat their animal more effectively and that treatments such as copper chelators or immunosuppressives cannot be used without histology. Owners usually want the least invasive option, but a poor, unrepresentative sample is worse than useless. It is important to explain to them the strengths and limitations of different techniques and the value of taking larger, representative wedge biopsies. Fine needle aspirates are only indicated for bile culture and cytology and to help diagnose lymphoma or hepatic lipidosis, but even then have to be viewed with caution. Ultrasound-guided trucut biopsies are often poorly representative of the disease as a whole and carry an increased risk of bleeding. I discuss the benefits of wedge biopsies in making a more reliable diagnosis, allowing more effective treatment. I am lucky to have access to laparoscopic biopsies which we made cost effective by matching the price of ultrasound-guided biopsies so that owners do not make a decision based on finances. Wedge biopsy at laparotomy is a good alternative but owners can be harder to persuade because it is more invasive.