Does your boyfriend have any other medical problems (besides gout and high blood pressure)? How old is he? What meds was he taking? Any travel? History of blood transfusion? Travel? Where was he born?
Any heart problems? Lung problems? Anyone in his family with heart or lung problems?
That is very helpful - and a couple other questions, do you know if the Bilirubin was elevated or normal and if his coagulation studies (prothrombin time) were normal?
An elevation of just ALT/AST suggests several different possibilities including viral hepatitis (which you said was negative), alcohol intake/alcohol liver disease (unlikely given what you mentioned about how little he drinks), hepatitis from medications like tylenol, auto-immune hepatitis (which can be checked by antibodies in the blood and would often run in the family), fatty liver which can just happen from a fatty diet or obesity, or chronic or inherited liver disease (often associated with family members who has history of liver disease and heart or lung problems at a young age). A workup for all of these things may leave us with a diagnosis of non-alcoholic steatohepatitis or NASH which can be totally harmless and have no symptoms. The fact that the other tests are normal suggests that overall his liver is healthy and functioning well, just experiencing some inflammation that may be temporary.
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