Case of the Month - May 2022

A 61-year old woman presented with one day of generalized weakness and a witnessed fall.

She had a history of congestive heart failure, end-stage renal disease, diabetes mellitus, asthma, and a recent 5th right toe amputation for osteomyelitis. She was receiving long term antibiotics (vancomycin, aztreonam, and flagyl) via a peripherally inserted central catheter.

Vital signs included a blood pressure of 227/95, pulse of 92, and temperature of 102.1°F. The physical exam revealed generalized weakness, and a wound vacuum-assisted closure device over the 5th right toe amputation site with no signs of erythema or drainage.

Blood cultures were obtained. After receiving hemodialysis, she decided to leave with her daughter against medical advice and agreed to continue intravenous antibiotics with the assistance of home health care.

The following organism was recovered from the aerobic bottle of one blood culture set. Growth on rice tween agar, and the results of a KOH with Calcofluor White preparation are shown. What is the organism?

Figure 1
Figure 1 - Gram stain (1000X)
Figure 2
Figure 2. Growth on rice tween agar
Figure 3
Figure 3. Calcofluor white preparation