Elevated liver enzymes (transaminases or ALT & AST) are often found by routine lab testing. If a lab report includes components of a comprehensive metabolic panel, additional values such as bilirubin, alkaline phosphatase, and albumin are also available. However, additional information, such as a complete clinical context, may or may not be available. Elevated transaminases are markers of a hepatocellular injury and probable diagnoses include pathologies which can cause hepatic and post-hepatic injury. These diagnoses are listed in the order of prevalence (NAFLD, alcoholic, viral, DILI) and also based upon chunks which have distinct pathophysiologic categories, such as immune mediated, infiltrative, and post-hepatic. Certain extra-hepatic pathologies which can cause transient elevation in transaminases are not listed on this clinical mind map. A few examples are congestive heart failure, starvation, and excessive exercise, which can cause transiently elevated liver enzymes.
Urgent/emergent situations include end stage liver failure resulting from any pathology, and are reflected in symptoms and signs of end stage liver failure. A patient may have an altered mental status, visible jaundice and abnormal vital signs. A few differentials are more likely than others to give rise to urgent/emergent situations.
Weighing and removing anchor bias involves a clinician taking a history, reviewing additional labs if available, reviewing past medical history and risk factors to obtain answers to high yield questions and medium yield questions, performing a physical exam, and ordering diagnostic tests. Knowledge of epidemiology and risk factors helps a clinician narrow down the differentials list in an efficient manner. A non-alcoholic fatty liver is highly prevalent in over-weight or obese populations. Baby boomers, patients with diabetes, and patients using intravenous drugs are at high risk for viral hepatitis. Patients with a family or personal history of immune mediated diseases are at risk for autoimmune liver disease. In addition, the pattern or degree of the rise in liver enzymes can help point a clinician to certain diagnoses. Patients with non-alcoholic fatty liver tend to have a mild and gradual rise in liver enzymes, whereas patients with an acute infection and/or an acute drug induced injury may experience a rapid rise in enzymes. Patients with a post hepatic or an obstructive pathology will experience a concomitant rise in markers, such as alkaline phosphatase and bilirubin levels.
Labs and imaging tests can be grouped together under the umbrella of liver work up and are listed on the mind map. This work up is typically done to determine the degree of liver damage.