hello and thanks for writing in to HCM i read your query and understand you are concerned regarding the elevated levels of ALT in your blood test ALT(previously SGPT) is alanine aminotransferase and is an enzyme mainly produced by liver and in small quantity by other organs like kidney,pancreas,heart etc(negligible amount) to give more clarity,these details would have been helpful: your age and gender?your weight?do you consume alcohol,if so how much and since when?do you have a history of liver disease or hepatitis in the past?do you take any medications regularly? as you said ,normal levels of alt would be sub-50,but please try not to stress about this 90 value. it can be even go up to those levels by a few days of strenuous exercise or muscle damage inflicted,can be liver disease like cirrhosis or hepatitis or can be caused by drugs like acetaminophen,statins,some antibiotics,aspirin,etc,in lead poisoning etc It is also common to have slight elevation of alt levels if you are in puberty and hitting your growth spurt i would recommend you to take an AST and GGT assay,along with total bilirubin test,so that the ratios and values can be compared before coming to a diagnosis what i would recommend to prevent a liver damage in the future would be: -avoid alcohol -maintain ideal weight -get hepatitis vaccination -avoid using intravenous drugs as abusive manner /avoid tattoos/dont handle blood products without precaution -use medications only when needed and as per prescription advise only.esp.acetaminophen dont worry about it and review said tests after a month,watch out for jaundice,abdominal pain or distension and fever if any hope it helps and clears your concern.good day