Hyperthyroidism may cause acute hepatic derangement limiting anti-thyroid therapies available in Graves disease. We present a case of Graves disease with co-existing autoimmune hepatitis (AIH).
An 18-year-old Aboriginal woman presented with four-day history of vomiting and painless jaundice, and one month of unintentional weight loss and recurrent syncope. Graves disease was confirmed with free T4 46pmol/L (10-20), free T3 27.0pmol/L (2.8-6.8), TSH <0.02mU/L, and positive thyroid-stimulating immunoglobulin 33IU/L (<0.1). Concurrent severe hepatic derangement with bilirubin 214 (<4), ALT 1640 U/L (0-34) and AST 2650 U/L (0-31) was associated with significant clinical jaundice and continued to worsen.
Lugol’s iodine and cholestyramine were used for initial control of thyrotoxicosis. Carbimazole and propylthiouracil were avoided due to hepatotoxicity. AIH was confirmed with positive anti-liver/anti-kidney microsomal type 1 (anti-LKM-1) antibodies >2560 titre, mild hepatosplenomegaly, and liver biopsy. Prednisolone 40mg, radioactive iodine and azathioprine successfully treated both conditions.
Hepatic dysfunction occurs in 37-65% of Graves disease and is often asymptomatic.1 It can be due to toxicity from excess thyroid hormones causing hepatocyte apoptosis, anti-thyroid medication, or concomitant hepatic ailment.1,2 Investigation for concomitant liver pathology should be performed if there is high index of suspicion e.g., lack of improvement in liver dysfunction with hyperthyroidism treatment, or dysfunction out-of-proportion to the hyperthyroid state.2
AIH is recorded in 1.6-6% of Graves disease.2 Anti-smooth muscle antibodies, anti-LKM-1 antibodies, or anti-liver cytosol type 1 antibodies are present in 95% of AIH cases.3 Glucocorticoids are the mainstay of therapy, with azathioprine as an adjunct.4
Anti-thyroid medications can cause liver dysfunction in 0.2%.5 Physicians may be hesitant to use these with concomitant AIH. Glucocorticoids, cholestyramine, and radioactive iodine are safe options.1,2,6
This case highlights a successful treatment of Graves disease with AIH with glucocorticoids and Lugol’s iodine, and to consider AIH as a concomitant pathology in Graves.