CYP27B1 and fungal infectious disease: Azole agents that are usually used to treat fungal infections are inhibitors of cytochrome P450-enzymes that also inhibit 1-alpha-hydroxylase (cytochrome-P450 family 27 subfamily B member 1; CYP27B1) and thus the conversion (activation) of 25(OH)D to 1,25(OH)2D. Case reports describe their successful use in patients with pathogenic CYP24A1 mutations [9,34].