I was mistaken in my previous post - my LDH was 264, but the Potassium Serum was 5.5 - both flagged as high. In my research (which is not always a good idea), there were some serious possible issues involved - or, a lab error. Anyone have a similar situation and can intelligently interpret these numbers? Another notification was sent to me last night at 11:29pm. Friday night. I guess they wanted me to know that there was a problem - but doctors do not work on weekends.