Possible side effect of Imuran

I was intrigued by the number of posts regarding fungal infections. I recently was scheduled for repair of hiatial hernia via endoscopically. The gastro was unable to complete the procedure due to a fungal infection that caused swelling in my throat. The gastro said the fungus could possibly be caused by my taking Imuran for my CIDP. He prescribed Prevacid, Famotidine, and Nystatin (mouth wash, gargle and swallow). Procedure is now on hold until the fungal infection is cleared up. Has anyone ever been told that a fungal infection was possibly caused by Imuran?