Biopsy should be done at the time of wound exploration (after initial surgical debridement) once the casualty has been evacuated from the theater of conflict (in theater if patient evacuation is delayed) and repeated on subsequent explorations if there are persistent findings (e.g., sepsis physiology, wound necrosis) raising suspicion for IFI.

1. Tissue samples should be obtained from each lower extremity in patients with bilateral lower extremity amputations. Sample all suspected areas.
2. Other sites sampled should be at the discretion of the operative surgeon.
3. At least one specimen should be taken from the junction of viable and necrotic tissue (the last piece of borderline-viable tissue removed).
4. For each site sampled, two tissue samples will be collected fresh in two separate sterile specimen containers.

- One specimen (1 cm3) for “rush” histopathological examination
- One specimen (1 cm3) for fungal and bacterial culture