80 y.o. male presents with fever and rigors after nephrostomy tube change on the last day of BCG immunotherapy for urothelial carcinoma. Routine bacterial blood cultures and urine culture are negative. Mycobacterial blood culture flags positive after 27 days of incubation. The bottle is subcultured to Middlebrook 7H11 agar. After 9 days of incubation, dry, rough, non-chromogenic colonies are observed, staining acid-fast (figure). The patient denies international travel, has no known TB contacts, and has a negative quantiFERON-TB Gold Plus.
|Kyle Rodino, Ph.D.
Fellow, Clinical Microbiology
|Nancy Wengenack, Ph.D.
Consultant, Clinical Microbiology
Professor of Laboratory Medicine and Pathology and Microbiology
Mayo Clinic College of Medicine