Sorry to joke, Gene.
Normal WBC sure makes infection less likely, and malignancy/vasculitis/drug reaction more likely. A reasonably healthy nonpediatric patient ought to be able to mount a white count to a life threatening infection.
I was thinking you had a sequestered infection that you could keep under some control while you probed, imaged, and diagnostic tested every pertinent part until you found the nidus, which could be cultured. The impression that Vanco seems to control this is important even if eventually wrong, since keeping him alive comes before the theory.
Malignancy and autoimmune disease are not going to take him soon like infection could. I imagine all the autoimmune tests are cooking. Since he sounds fragile, I would continue the antibiotics until everything between the stem and stern are checked.
Then comes the magic... steroids.
