GPT and tularemia: Serum biomarkers of tissue damage, lactate dehydrogenase (LDH), hepatic damage biomarkers aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and kidney damage biomarker blood urea nitrogen (BUN) steadily increased with progression of tularemia, with significant increases in values over the pre-challenge baseline typically starting on Days 4 to 6 for LDH, Day 6 for AST and ALT, and Day 6 and later for BUN (not shown).