1. Department of Infectious Diseases, University of Colorado School of Medicine, Aurora, Colorado, USA
2. Hospital Infantil de Mexico, Federico Gomez, Mexico City, Mexico
3. Deparment of Pathology, Denver Health Medical Center, Denver, Colorado, USA
4. Department of Pharmacy, Denver Health Medical Center, Denver, Colorado, USA
5. Department of Infectious Diseases, Denver Health Medical Center, Denver, Colorado, USA