C/def

I am assuming you mean you are Protein C def Positive?

A protein that appears, usually within 24 hours, in the blood during the acute stage of inflammatory disorders such as rheumatic fever, or after a myocardial infarction (heart attack). The serum level of CRP is a sensitive indicator and monitor of rheumatic activity.

Or are we talking about the CDF/cdf infection?

Clostridium difficile or CDF/cdf' (commonly mistaken pronunciation), alternatively and correctly pronounced /kl s tr di m d f s li/) (also referred to as C. diff or C-diff) is a species of bacteria of the genus Clostridium which are gram-positive, anaerobic, spore-forming rods (bacillus). C. difficile is the most significant cause of pseudomembranous colitis, a severe infection of the colon, often after normal gut flora is eradicated by the use of antibiotics. Treatment is by stopping any antibiotics and commencing specific anticlostridial antibiotics, e.g. metronidazole