Statins in liver disease?

A middle-aged patient arrives to his regularly scheduled clinic appointment looking for refills of his medication. His PMH includes HTN, hyperlipidemia, diabetes mellitus, obesity, and cirrhosis secondary to nonalcoholic fatty liver disease. His medications include antihypertensive and antihyperglycemic drugs in addition to atorvastatin 80 mg by mouth daily. At this time, you recall that statins have a risk for hepatotoxicity and are concerned whether it should be refilled at this time. What are the considerations for continuing statin therapy in this patient with known liver disease?

Elevation of liver enzymes is a well-known risk of statin therapy. Since the first statin was approved by the FDA in 1987, regular monitoring of liver enzymes to screen for elevations was routine practice. However, in 2012, the FDA revised the prescribing information for all statins to recommend serum aminotransferases be measured at baseline and then only thereafter if clinically indicated. There were primarily two reasons for this change:

“Sulfa” allergy cross-reactivity

Let’s start with a patient scenario.  A patient presents to the emergency room experiencing a heart failure exacerbation.  When entering the order for intravenous diuretics, you note that a cross-reactivity warning has popped up for a “sulfa” allergy.  What evidence is there for cross-reactivity between Loop diuretics and “sulfa” allergy and how should this affect your decision?